From 22df891893d30e9906d0b14fc3ae5d8e67d500b2 Mon Sep 17 00:00:00 2001 From: Cliff Click Date: Sat, 3 Oct 2026 14:03:48 -0700 Subject: Chapter renumber, and split ch 17 Renumber chapters 10a, 10b, 11, 12, 13, 14 -> 10, 11, 13, 12, [11,14]. Split ch 17 into a 17a and 17b; shuffle around im/mutable syntax to be consistent, and present it more slowly. THe new immutable syntax is pushed through all later chapters --- chapter17b/Makefile | 106 ++ chapter17b/README.md | 112 ++ chapter17b/chapter17b.iml | 28 + chapter17b/docs/17-grammar.md | 22 + chapter17b/docs/Makefile | 12 + chapter17b/pom.xml | 18 + .../src/main/java/com/seaofnodes/simple/Ary.java | 217 +++ .../com/seaofnodes/simple/GlobalCodeMotion.java | 238 ++++ .../main/java/com/seaofnodes/simple/IRPrinter.java | 33 + .../main/java/com/seaofnodes/simple/IterPeeps.java | 211 +++ .../main/java/com/seaofnodes/simple/Parser.java | 1450 ++++++++++++++++++++ .../src/main/java/com/seaofnodes/simple/Utils.java | 53 + .../java/com/seaofnodes/simple/node/AddFNode.java | 37 + .../java/com/seaofnodes/simple/node/AddNode.java | 186 +++ .../java/com/seaofnodes/simple/node/AndNode.java | 61 + .../java/com/seaofnodes/simple/node/BoolNode.java | 114 ++ .../com/seaofnodes/simple/node/BulkMemPhiNode.java | 237 ++++ .../java/com/seaofnodes/simple/node/CFGNode.java | 136 ++ .../java/com/seaofnodes/simple/node/CProjNode.java | 61 + .../java/com/seaofnodes/simple/node/CastNode.java | 37 + .../com/seaofnodes/simple/node/ConstantNode.java | 56 + .../java/com/seaofnodes/simple/node/DivFNode.java | 39 + .../java/com/seaofnodes/simple/node/DivNode.java | 40 + .../java/com/seaofnodes/simple/node/IfNode.java | 62 + .../java/com/seaofnodes/simple/node/LoadNode.java | 222 +++ .../java/com/seaofnodes/simple/node/LoopNode.java | 61 + .../com/seaofnodes/simple/node/MemMergeNode.java | 90 ++ .../java/com/seaofnodes/simple/node/MemOpNode.java | 62 + .../com/seaofnodes/simple/node/MemPhiNode.java | 42 + .../com/seaofnodes/simple/node/MinusFNode.java | 30 + .../java/com/seaofnodes/simple/node/MinusNode.java | 36 + .../java/com/seaofnodes/simple/node/MulFNode.java | 44 + .../java/com/seaofnodes/simple/node/MulNode.java | 61 + .../java/com/seaofnodes/simple/node/MultiNode.java | 20 + .../java/com/seaofnodes/simple/node/NeverNode.java | 22 + .../java/com/seaofnodes/simple/node/NewNode.java | 60 + .../main/java/com/seaofnodes/simple/node/Node.java | 610 ++++++++ .../java/com/seaofnodes/simple/node/NotNode.java | 39 + .../java/com/seaofnodes/simple/node/OrNode.java | 58 + .../java/com/seaofnodes/simple/node/OutNode.java | 7 + .../java/com/seaofnodes/simple/node/PhiNode.java | 201 +++ .../java/com/seaofnodes/simple/node/ProjNode.java | 47 + .../com/seaofnodes/simple/node/ReadOnlyNode.java | 26 + .../com/seaofnodes/simple/node/RegionNode.java | 119 ++ .../com/seaofnodes/simple/node/ReturnNode.java | 42 + .../com/seaofnodes/simple/node/RoundF32Node.java | 33 + .../java/com/seaofnodes/simple/node/SarNode.java | 54 + .../java/com/seaofnodes/simple/node/ScopeNode.java | 416 ++++++ .../java/com/seaofnodes/simple/node/ShlNode.java | 57 + .../java/com/seaofnodes/simple/node/ShrNode.java | 50 + .../java/com/seaofnodes/simple/node/StartNode.java | 36 + .../java/com/seaofnodes/simple/node/StopNode.java | 89 ++ .../java/com/seaofnodes/simple/node/StoreNode.java | 125 ++ .../com/seaofnodes/simple/node/StructNode.java | 45 + .../java/com/seaofnodes/simple/node/SubFNode.java | 37 + .../java/com/seaofnodes/simple/node/SubNode.java | 64 + .../com/seaofnodes/simple/node/ToFloatNode.java | 25 + .../java/com/seaofnodes/simple/node/XCtrlNode.java | 14 + .../java/com/seaofnodes/simple/node/XorNode.java | 58 + .../simple/print/SimpleGraphAdapter.java | 42 + .../simple/print/SimpleGraphObserver.java | 45 + .../java/com/seaofnodes/simple/type/Field.java | 77 ++ .../main/java/com/seaofnodes/simple/type/Type.java | 222 +++ .../java/com/seaofnodes/simple/type/TypeFloat.java | 120 ++ .../com/seaofnodes/simple/type/TypeInteger.java | 133 ++ .../java/com/seaofnodes/simple/type/TypeMem.java | 69 + .../com/seaofnodes/simple/type/TypeMemPtr.java | 123 ++ .../com/seaofnodes/simple/type/TypeStruct.java | 262 ++++ .../java/com/seaofnodes/simple/type/TypeTuple.java | 95 ++ .../java/com/seaofnodes/simple/BrainFuckTest.java | 72 + .../java/com/seaofnodes/simple/Chapter01Test.java | 100 ++ .../java/com/seaofnodes/simple/Chapter02Test.java | 60 + .../java/com/seaofnodes/simple/Chapter03Test.java | 69 + .../java/com/seaofnodes/simple/Chapter04Test.java | 165 +++ .../java/com/seaofnodes/simple/Chapter05Test.java | 227 +++ .../java/com/seaofnodes/simple/Chapter06Test.java | 294 ++++ .../java/com/seaofnodes/simple/Chapter07Test.java | 221 +++ .../java/com/seaofnodes/simple/Chapter08Test.java | 208 +++ .../java/com/seaofnodes/simple/Chapter09Test.java | 301 ++++ .../java/com/seaofnodes/simple/Chapter10Test.java | 572 ++++++++ .../java/com/seaofnodes/simple/Chapter11Test.java | 64 + .../java/com/seaofnodes/simple/Chapter12Test.java | 196 +++ .../java/com/seaofnodes/simple/Chapter13Test.java | 554 ++++++++ .../com/seaofnodes/simple/Chapter14FloatTest.java | 83 ++ .../java/com/seaofnodes/simple/Chapter14Test.java | 227 +++ .../java/com/seaofnodes/simple/Chapter15Test.java | 387 ++++++ .../java/com/seaofnodes/simple/Chapter16Test.java | 171 +++ .../java/com/seaofnodes/simple/Chapter17aTest.java | 107 ++ .../java/com/seaofnodes/simple/Chapter17bTest.java | 500 +++++++ .../seaofnodes/simple/CompoundAssignmentTest.java | 77 ++ .../java/com/seaofnodes/simple/FuzzerWrap.java | 58 + .../java/com/seaofnodes/simple/MutabilityTest.java | 63 + .../java/com/seaofnodes/simple/SchedulerTest.java | 73 + .../test/java/com/seaofnodes/simple/TypeTest.java | 157 +++ .../com/seaofnodes/simple/evaluator/Evaluator.java | 374 +++++ .../com/seaofnodes/simple/evaluator/Scheduler.java | 596 ++++++++ .../java/com/seaofnodes/simple/fuzzer/Fuzzer.java | 199 +++ .../com/seaofnodes/simple/fuzzer/FuzzerUtils.java | 142 ++ .../java/com/seaofnodes/simple/fuzzer/Reducer.java | 176 +++ .../seaofnodes/simple/fuzzer/ScriptGenerator.java | 882 ++++++++++++ 100 files changed, 15131 insertions(+) create mode 100644 chapter17b/Makefile create mode 100644 chapter17b/README.md create mode 100644 chapter17b/chapter17b.iml create mode 100644 chapter17b/docs/17-grammar.md create mode 100644 chapter17b/docs/Makefile create mode 100644 chapter17b/pom.xml create mode 100644 chapter17b/src/main/java/com/seaofnodes/simple/Ary.java create mode 100644 chapter17b/src/main/java/com/seaofnodes/simple/GlobalCodeMotion.java create mode 100644 chapter17b/src/main/java/com/seaofnodes/simple/IRPrinter.java create mode 100644 chapter17b/src/main/java/com/seaofnodes/simple/IterPeeps.java create mode 100644 chapter17b/src/main/java/com/seaofnodes/simple/Parser.java create mode 100644 chapter17b/src/main/java/com/seaofnodes/simple/Utils.java create mode 100644 chapter17b/src/main/java/com/seaofnodes/simple/node/AddFNode.java create mode 100644 chapter17b/src/main/java/com/seaofnodes/simple/node/AddNode.java create mode 100644 chapter17b/src/main/java/com/seaofnodes/simple/node/AndNode.java create mode 100644 chapter17b/src/main/java/com/seaofnodes/simple/node/BoolNode.java create mode 100644 chapter17b/src/main/java/com/seaofnodes/simple/node/BulkMemPhiNode.java create mode 100644 chapter17b/src/main/java/com/seaofnodes/simple/node/CFGNode.java create mode 100644 chapter17b/src/main/java/com/seaofnodes/simple/node/CProjNode.java create mode 100644 chapter17b/src/main/java/com/seaofnodes/simple/node/CastNode.java create mode 100644 chapter17b/src/main/java/com/seaofnodes/simple/node/ConstantNode.java create mode 100644 chapter17b/src/main/java/com/seaofnodes/simple/node/DivFNode.java create mode 100644 chapter17b/src/main/java/com/seaofnodes/simple/node/DivNode.java create mode 100644 chapter17b/src/main/java/com/seaofnodes/simple/node/IfNode.java create mode 100644 chapter17b/src/main/java/com/seaofnodes/simple/node/LoadNode.java create mode 100644 chapter17b/src/main/java/com/seaofnodes/simple/node/LoopNode.java create mode 100644 chapter17b/src/main/java/com/seaofnodes/simple/node/MemMergeNode.java create mode 100644 chapter17b/src/main/java/com/seaofnodes/simple/node/MemOpNode.java create mode 100644 chapter17b/src/main/java/com/seaofnodes/simple/node/MemPhiNode.java create mode 100644 chapter17b/src/main/java/com/seaofnodes/simple/node/MinusFNode.java create mode 100644 chapter17b/src/main/java/com/seaofnodes/simple/node/MinusNode.java create mode 100644 chapter17b/src/main/java/com/seaofnodes/simple/node/MulFNode.java create mode 100644 chapter17b/src/main/java/com/seaofnodes/simple/node/MulNode.java create mode 100644 chapter17b/src/main/java/com/seaofnodes/simple/node/MultiNode.java create mode 100644 chapter17b/src/main/java/com/seaofnodes/simple/node/NeverNode.java create mode 100644 chapter17b/src/main/java/com/seaofnodes/simple/node/NewNode.java create mode 100644 chapter17b/src/main/java/com/seaofnodes/simple/node/Node.java create mode 100644 chapter17b/src/main/java/com/seaofnodes/simple/node/NotNode.java create mode 100644 chapter17b/src/main/java/com/seaofnodes/simple/node/OrNode.java create mode 100644 chapter17b/src/main/java/com/seaofnodes/simple/node/OutNode.java create mode 100644 chapter17b/src/main/java/com/seaofnodes/simple/node/PhiNode.java create mode 100644 chapter17b/src/main/java/com/seaofnodes/simple/node/ProjNode.java create mode 100644 chapter17b/src/main/java/com/seaofnodes/simple/node/ReadOnlyNode.java create mode 100644 chapter17b/src/main/java/com/seaofnodes/simple/node/RegionNode.java create mode 100644 chapter17b/src/main/java/com/seaofnodes/simple/node/ReturnNode.java create mode 100644 chapter17b/src/main/java/com/seaofnodes/simple/node/RoundF32Node.java create mode 100644 chapter17b/src/main/java/com/seaofnodes/simple/node/SarNode.java create mode 100644 chapter17b/src/main/java/com/seaofnodes/simple/node/ScopeNode.java create mode 100644 chapter17b/src/main/java/com/seaofnodes/simple/node/ShlNode.java create mode 100644 chapter17b/src/main/java/com/seaofnodes/simple/node/ShrNode.java create mode 100644 chapter17b/src/main/java/com/seaofnodes/simple/node/StartNode.java create mode 100644 chapter17b/src/main/java/com/seaofnodes/simple/node/StopNode.java create mode 100644 chapter17b/src/main/java/com/seaofnodes/simple/node/StoreNode.java create mode 100644 chapter17b/src/main/java/com/seaofnodes/simple/node/StructNode.java create mode 100644 chapter17b/src/main/java/com/seaofnodes/simple/node/SubFNode.java create mode 100644 chapter17b/src/main/java/com/seaofnodes/simple/node/SubNode.java create mode 100644 chapter17b/src/main/java/com/seaofnodes/simple/node/ToFloatNode.java create mode 100644 chapter17b/src/main/java/com/seaofnodes/simple/node/XCtrlNode.java create mode 100644 chapter17b/src/main/java/com/seaofnodes/simple/node/XorNode.java create mode 100644 chapter17b/src/main/java/com/seaofnodes/simple/print/SimpleGraphAdapter.java create mode 100644 chapter17b/src/main/java/com/seaofnodes/simple/print/SimpleGraphObserver.java create mode 100644 chapter17b/src/main/java/com/seaofnodes/simple/type/Field.java create mode 100644 chapter17b/src/main/java/com/seaofnodes/simple/type/Type.java create mode 100644 chapter17b/src/main/java/com/seaofnodes/simple/type/TypeFloat.java create mode 100644 chapter17b/src/main/java/com/seaofnodes/simple/type/TypeInteger.java create mode 100644 chapter17b/src/main/java/com/seaofnodes/simple/type/TypeMem.java create mode 100644 chapter17b/src/main/java/com/seaofnodes/simple/type/TypeMemPtr.java create mode 100644 chapter17b/src/main/java/com/seaofnodes/simple/type/TypeStruct.java create mode 100644 chapter17b/src/main/java/com/seaofnodes/simple/type/TypeTuple.java create mode 100644 chapter17b/src/test/java/com/seaofnodes/simple/BrainFuckTest.java create mode 100644 chapter17b/src/test/java/com/seaofnodes/simple/Chapter01Test.java create mode 100644 chapter17b/src/test/java/com/seaofnodes/simple/Chapter02Test.java create mode 100644 chapter17b/src/test/java/com/seaofnodes/simple/Chapter03Test.java create mode 100644 chapter17b/src/test/java/com/seaofnodes/simple/Chapter04Test.java create mode 100644 chapter17b/src/test/java/com/seaofnodes/simple/Chapter05Test.java create mode 100644 chapter17b/src/test/java/com/seaofnodes/simple/Chapter06Test.java create mode 100644 chapter17b/src/test/java/com/seaofnodes/simple/Chapter07Test.java create mode 100644 chapter17b/src/test/java/com/seaofnodes/simple/Chapter08Test.java create mode 100644 chapter17b/src/test/java/com/seaofnodes/simple/Chapter09Test.java create mode 100644 chapter17b/src/test/java/com/seaofnodes/simple/Chapter10Test.java create mode 100644 chapter17b/src/test/java/com/seaofnodes/simple/Chapter11Test.java create mode 100644 chapter17b/src/test/java/com/seaofnodes/simple/Chapter12Test.java create mode 100644 chapter17b/src/test/java/com/seaofnodes/simple/Chapter13Test.java create mode 100644 chapter17b/src/test/java/com/seaofnodes/simple/Chapter14FloatTest.java create mode 100644 chapter17b/src/test/java/com/seaofnodes/simple/Chapter14Test.java create mode 100644 chapter17b/src/test/java/com/seaofnodes/simple/Chapter15Test.java create mode 100644 chapter17b/src/test/java/com/seaofnodes/simple/Chapter16Test.java create mode 100644 chapter17b/src/test/java/com/seaofnodes/simple/Chapter17aTest.java create mode 100644 chapter17b/src/test/java/com/seaofnodes/simple/Chapter17bTest.java create mode 100644 chapter17b/src/test/java/com/seaofnodes/simple/CompoundAssignmentTest.java create mode 100644 chapter17b/src/test/java/com/seaofnodes/simple/FuzzerWrap.java create mode 100644 chapter17b/src/test/java/com/seaofnodes/simple/MutabilityTest.java create mode 100644 chapter17b/src/test/java/com/seaofnodes/simple/SchedulerTest.java create mode 100644 chapter17b/src/test/java/com/seaofnodes/simple/TypeTest.java create mode 100644 chapter17b/src/test/java/com/seaofnodes/simple/evaluator/Evaluator.java create mode 100644 chapter17b/src/test/java/com/seaofnodes/simple/evaluator/Scheduler.java create mode 100644 chapter17b/src/test/java/com/seaofnodes/simple/fuzzer/Fuzzer.java create mode 100644 chapter17b/src/test/java/com/seaofnodes/simple/fuzzer/FuzzerUtils.java create mode 100644 chapter17b/src/test/java/com/seaofnodes/simple/fuzzer/Reducer.java create mode 100644 chapter17b/src/test/java/com/seaofnodes/simple/fuzzer/ScriptGenerator.java (limited to 'chapter17b') diff --git a/chapter17b/Makefile b/chapter17b/Makefile new file mode 100644 index 00000000..3f1e53ff --- /dev/null +++ b/chapter17b/Makefile @@ -0,0 +1,106 @@ +SHELL := /bin/bash +# Shared packaging target; included after chapter source variables below. +.DELETE_ON_ERROR: + +# for printing variable values +# usage: make print-VARIABLE +# > VARIABLE = value_of_variable +print-% : ; @echo $* = $($*) + +# literal space +space := $() $() + +# Decide OS-specific questions +# jar-file seperator +ifeq ($(OS),Windows_NT) + SEP = ; +else + SEP = : +endif +# Find a reasonable ctags. +CTAGS = $(shell which ctags) +# Hack for MacOS: /usr/bin/ctags is unfriendly, so look for ctags from brew +ifeq ($(UNAME),Darwin) + CTAGS = $(shell brew list ctags 2> /dev/null | grep bin/ctags) +endif + +# Fun Args to javac. Mostly limit to java8 source definitions, and fairly +# aggressive lint warnings. +JAVAC_ARGS = -g + +# Source code +SIMPLE := com/seaofnodes/simple +SRC := src/main/java +TST := src/test/java +CLZDIR:= build/classes +main_javas := $(wildcard $(SRC)/$(SIMPLE)/*java $(SRC)/$(SIMPLE)/*/*java) +test_javas := $(wildcard $(TST)/$(SIMPLE)/*java $(TST)/$(SIMPLE)/*/*java) +main_classes := $(patsubst $(SRC)/%java,$(CLZDIR)/main/%class,$(main_javas)) +include $(firstword $(wildcard ../graph/graph.mk graph/graph.mk)) +include $(firstword $(wildcard ../print/print.mk print/print.mk)) +test_classes := $(patsubst $(TST)/%java,$(CLZDIR)/test/%class,$(test_javas)) +test_cp := $(patsubst $(TST)/$(SIMPLE)/%.java,com.seaofnodes.simple.%,$(wildcard $(TST)/$(SIMPLE)/*Test.java)) +classes = $(main_classes) $(test_classes) +# All the libraries +libs = $(wildcard lib/*jar) +jars = $(subst $(space),$(SEP),$(libs)) + + +default_targets := $(main_classes) $(test_classes) +# Optionally add ctags to the default target if a reasonable one was found. +ifneq ($(CTAGS),) +default_targets += tags +endif + +default: $(default_targets) + +# Compile just the out-of-date files +$(main_classes): build/classes/main/%class: $(SRC)/%java $(graph_javas) $(print_javas) + @echo "compiling " $@ " because " $? + @[ -d $(CLZDIR)/main ] || mkdir -p $(CLZDIR)/main + @javac $(JAVAC_ARGS) -cp "$(CLZDIR)/main$(SEP)$(jars)" -sourcepath $(SRC) -d $(CLZDIR)/main $(main_javas) + +$(test_classes): $(CLZDIR)/test/%class: $(TST)/%java $(main_classes) + @echo "compiling " $@ " because " $? + @[ -d $(CLZDIR)/test ] || mkdir -p $(CLZDIR)/test + @javac $(JAVAC_ARGS) -cp "$(CLZDIR)/test$(SEP)$(CLZDIR)/main$(SEP)$(jars)" -sourcepath $(TST) -d $(CLZDIR)/test $(test_javas) + +# Base launch line for JVM tests +JVM=nice java -ea -cp "build/classes/main${SEP}${jars}${SEP}$(CLZDIR)/test" + +tests: $(default_targets) + @echo "testing " $(test_cp) + @$(JVM) org.junit.runner.JUnitCore $(test_cp) com.seaofnodes.simple.FuzzerWrap + +fuzzer: $(default_targets) + @echo "fuzzing " $(test_cp) + @$(JVM) org.junit.runner.JUnitCore com.seaofnodes.simple.FuzzerWrap + + +.PHONY: clean +clean: + rm -rf build + rm -f TAGS + (find . -name "*~" -exec rm {} \; 2>/dev/null; exit 0) + +# Download libs from maven +lib: lib/junit-4.12.jar lib/hamcrest-core-1.3.jar + +# Jars +lib/junit-4.12.jar: + @[ -d lib ] || mkdir -p lib + @(cd lib; wget https://repo1.maven.org/maven2/junit/junit/4.12/junit-4.12.jar) + +lib/hamcrest-core-1.3.jar: + @[ -d lib ] || mkdir -p lib + @(cd lib; wget https://repo1.maven.org/maven2/org/hamcrest/hamcrest-core/1.3/hamcrest-core-1.3.jar) + +# Build emacs tags (part of a tasty emacs ide experience) +tags: $(main_javas) $(test_javas) + @rm -f TAGS + @$(CTAGS) -e --recurse=yes --extra=+q --fields=+fksaiS $(SRC) $(TST) + +include $(firstword $(wildcard ../build-support/chapter-release.mk build-support/chapter-release.mk)) + +.PHONY: build +build: $(main_classes) diff --git a/chapter17b/README.md b/chapter17b/README.md new file mode 100644 index 00000000..5bdfb9e4 --- /dev/null +++ b/chapter17b/README.md @@ -0,0 +1,112 @@ +# Chapter 17b: Syntax Sugar + +[Previous: Chapter 17a](../chapter17a/README.md) | +[Next: Chapter 18](../chapter18/README.md) + + +## Table of Contents + +1. [Pre/Post-increment](#prepost-increment) +2. [Operator assignment](#operator-assignment) +3. [var/val](#var--val) +4. [Trinary](#trinary) +5. [For Loops](#for-loops) +6. [Memory effects](#memory-effects) + +Chapter 17a established the permissions checked by assignments. This chapter +adds shorter ways to write assignments and control flow without changing those +permissions. Chapter 18 then introduces functions and calls. + +## Pre/Post-increment + +Allow `arg++` and `arg--` with the usual meanings; the value is updated and the +expression is the pre-update value. Greedy match is used so `arg---arg` parses +as `(arg--)-arg`. + +Also allows `s.fld++` and `ary[idx]++`, and their `--` variants. + +Allow pre-increment for identifiers only, for now: `--pc`. + + +## Operator assignment + +Along the same lines as post-increment, we now allow `op=` assignment +on local variables with semantics similar to other languages. The supported +operators are `+=`, `-=`, `*=`, `/=`, `&=`, `|=`, `^=`, `<<=`, `>>=`, and `>>>=`. +Bitwise and shift assignments require integer operands; `>>=` preserves the sign +while `>>>=` shifts in zeros. The assignment evaluates its right-hand side once, +stores the result narrowed to the variable's type, and yields that stored value. +Assignments associate right-to-left, as in `x |= y <<= 2`. + + + +## var & val + +`var` and `val` declare variables and infer their types; `var` infers a +reassignable binding while `val` infers a fixed binding. Both preserve access +permissions from the initializing expression. Neither makes a writable object +read-only. The two independent permissions come from [Chapter +17a](../chapter17a/README.md). + +```cpp +struct Point { int x; }; +val p = new Point; // Fixed binding to a writable new object +p.x = 3; // Allowed +// p = new Point; // Error: fixed binding +Point view = p; // Explicit read-only view +var q = view; // Reassignable binding, still read-only access +// q.x = 4; // Error: cannot restore write permission by inference +``` + +The initializer is required for type inference. Primitives infer their broad +numeric type (`int` or `flt`); references retain their access permissions. A +reassignable inferred reference allows null so it can later hold the empty +value. Explicit types retain their declared width and nullability. Function +parameters still require explicit types. + +## Trinary + +Allow `pred ? e_true : e_false`. Also allow `pred ? e_true`, where the false result +is the zero type version of the true result. + + +## For Loops + +Allow C/C++ style `for` loops: + +`for( init; test; next ) body` + +Example: + +```cpp +int sum=0; +for( int i=0; i + + + + + + + + + + + + + + + + + + + + + + + + + + + diff --git a/chapter17b/docs/17-grammar.md b/chapter17b/docs/17-grammar.md new file mode 100644 index 00000000..9a70f323 --- /dev/null +++ b/chapter17b/docs/17-grammar.md @@ -0,0 +1,22 @@ +# Chapter 17b grammar additions + +Start with [Chapter 17a's declaration syntax](../../chapter17a/docs/17-grammar.md). +This chapter adds inference, assignment shortcuts, conditional expressions, and +`for` loops. Access and binding permissions keep the same meaning. + +```text +inferredDeclaration = ("var" | "val") ("!" | "~")? identifier "=" assignment +assignment = expression (assignmentOperator assignment)? +assignmentOperator = "=" | "+=" | "-=" | "*=" | "/=" | "&=" | "|=" | "^=" + | "<<=" | ">>=" | ">>>=" +expression = bitwise ("?" assignment (":" assignment)?)? +prefixUpdate = ("++" | "--") identifier +postfixUpdate = lvalue ("++" | "--") +forStatement = "for" "(" declarationOrExpression? ";" assignment? ";" + assignment? ")" statement +``` + +Declarations can contain several comma-separated names. `var` permits +reassignment and `val` fixes the binding; both retain the initializer's reference +permissions. Postfix updates also support fields and array elements. Prefix +updates currently support local names. See the README for evaluation order. diff --git a/chapter17b/docs/Makefile b/chapter17b/docs/Makefile new file mode 100644 index 00000000..12659b8f --- /dev/null +++ b/chapter17b/docs/Makefile @@ -0,0 +1,12 @@ +GV := $(wildcard *.gv) +SVG := $(patsubst %.gv,%.svg,$(GV)) + +.PHONY: all +all: $(SVG) + +%.svg: %.gv + dot -Tsvg $< > $@ + +.PHONY: clean +clean: + @rm -f $(SVG) diff --git a/chapter17b/pom.xml b/chapter17b/pom.xml new file mode 100644 index 00000000..1eef8185 --- /dev/null +++ b/chapter17b/pom.xml @@ -0,0 +1,18 @@ + + + 4.0.0 + + com.seaofnodes + simple + 1.0 + + chapter17b + jar + Chapter 17b + + ${project.basedir}/../graph + ${project.basedir}/../print + + diff --git a/chapter17b/src/main/java/com/seaofnodes/simple/Ary.java b/chapter17b/src/main/java/com/seaofnodes/simple/Ary.java new file mode 100644 index 00000000..8654d41e --- /dev/null +++ b/chapter17b/src/main/java/com/seaofnodes/simple/Ary.java @@ -0,0 +1,217 @@ +package com.seaofnodes.simple; + +import java.lang.StringBuilder; +import java.lang.reflect.Array; +import java.util.*; + +// ArrayList with saner syntax +public class Ary extends AbstractList implements List { + public E[] _es; + public int _len; + + public Ary(E[] es) { this(es,es.length); } + public Ary(E[] es, int len) { if( es.length==0 ) es=Arrays.copyOf(es,1); _es=es; _len=len; } + @SuppressWarnings("unchecked") + public Ary(Class clazz) { this((E[]) Array.newInstance(clazz, 1),0); } + + /** @return list is empty */ + public boolean isEmpty() { return _len==0; } + /** @return active list length */ + public int len() { return _len; } + public int size() { return len(); } + + /** @param i element index + * @return element being returned; throws if OOB + * @exception AIOOBE if !(0 <= i < _len) + */ + public E get( int i ) { return at(i); } + public E at( int i ) { + range_check(i); + return _es[i]; + } + + /** @return last element */ + public E last( ) { return at(_len-1); } + + /** Add element in amortized constant time + * @param e Element to add at end of list + **/ + public E push( E e ) { + if( _len >= _es.length ) _es = Arrays.copyOf(_es,Math.max(1,_es.length<<1)); + return (_es[_len++] = e); + } + /** @return remove and return last element */ + public E pop( ) { + range_check(0); + return _es[--_len]; + } + @Override public E removeLast() { return pop(); } + + + /** Add element in amortized constant time + * @param e Element to add at end of list + * @return true */ + public boolean add( E e ) { + if( _len >= _es.length ) _es = Arrays.copyOf(_es,Math.max(1,_es.length<<1)); + _es[_len++] = e; + return true; + } + + ///** Slow, linear-time, element insert. Preserves order. + // * @param i index to insert at, between 0 and _len inclusive. + // * @param e Element to insert + // */ + //public void insert( int i, E e ) { + // if( i < 0 || i>_len ) + // throw new ArrayIndexOutOfBoundsException(""+i+" >= "+_len); + // if( _len >= _es.length ) _es = Arrays.copyOf(_es,Math.max(1,_es.length<<1)); + // System.arraycopy(_es,i,_es,i+1,(_len++)-i); + // _es[i] = e; + //} + + /** Fast, constant-time, element removal. Does not preserve order + * @param i element to be removed + * @return element removed */ + public E del( int i ) { + range_check(i); + E tmp = _es[i]; + _es[i]=_es[--_len]; + return tmp; + } + + ///** Element removal, using '=='. Does not preserve order. + // * @param e element to be removed + // * @return element removed */ + //public E del( E e ) { + // for( int i=0; i<_len; i++ ) { + // E tmp = _es[i]; + // if( tmp==e ) { + // _es[i]=_es[--_len]; + // return tmp; + // } + // } + // return null; + //} + + /** Slow, linear-time, element removal. Preserves order. + * @param i element to be removed + * @return element removed */ + @Override public E remove( int i ) { + range_check(i); + E e = _es[i]; + System.arraycopy(_es,i+1,_es,i,(--_len)-i); + return e; + } + + /** Remove all elements */ + public void clear( ) { _len=0; } + + /** Set existing element + * @param i element to set + * @param e value to set + * @return old value + * @exception AIOOBE if !(0 <= i < _len) + */ + public E set( int i, E e ) { + range_check(i); + E old = _es[i]; + _es[i] = e; + return old; + } + + public Ary setLen( int len ) { + if( len > _len ) + while( len>= _es.length ) _es = Arrays.copyOf(_es,_es.length<<1); + _len = len; + while( _es.length > (len<<1) ) // Shrink if hugely too large + _es = Arrays.copyOf(_es,_es.length>>1); + Arrays.fill(_es,len,_es.length,null); + return this; + } + + /** @param c Collection to be added */ + public boolean addAll( Collection c ) { + if( c==null ) return false; + for( E e : c ) add(e); + return true; + } + public Ary addAll( Iterable it ) { for( E e : it ) add(e); return this; } + + /** @param es Array to be added */ + public Ary addAll( F[] es ) { + if( es==null || es.length==0 ) return this; + while( _len+es.length > _es.length ) _es = Arrays.copyOf(_es,_es.length<<1); + System.arraycopy(es,0,_es,_len,es.length); + _len += es.length; + return this; + } + + /** @param c Collection to be added */ + public Ary addAll( Ary c ) { + if( c==null || c._len==0 ) return this; + while( _len+c._len > _es.length ) _es = Arrays.copyOf(_es,_es.length<<1); + System.arraycopy(c._es,0,_es,_len,c._len); + _len += c._len; + return this; + } + + /** @return compact array version */ + public E[] asAry() { return Arrays.copyOf(_es,_len); } + + /** Sorts in-place + * @param c Comparator to sort by */ + public void sort_update(Comparator c ) { Arrays.sort(_es, 0, _len, c); } + + /** Find the first matching element using ==, or -1 if none. Note that + * most del calls shuffle the list, so the first element might be random. + * @param e Element to find + * @return index of first matching element, or -1 if none */ + public int find( E e ) { + for( int i=0; i<_len; i++ ) if( _es[i]==e ) return i; + return -1; + } + + + /** @return an iterator */ + @Override public Iterator iterator() { return new Iter(); } + private class Iter implements Iterator { + int _i=0; + @Override public boolean hasNext() { return _i<_len; } + @Override public E next() { return _es[_i++]; } + } + + @Override public String toString() { + StringBuilder sb = new StringBuilder().append('{'); + for( int i=0; i<_len; i++ ) { + if( i>0 ) sb.append(','); + if( _es[i] != null ) sb.append(_es[i].toString()); + } + return sb.append('}').toString(); + } + + private void range_check( int i ) { + if( i < 0 || i>=_len ) + throw new ArrayIndexOutOfBoundsException(""+i+" >= "+_len); + } + + // Note that the hashCode() and equals() are not invariant to changes in the + // underlying array. If the hashCode() is used (e.g., inserting into a + // HashMap) and the then the array changes, the hashCode() will change also. + @Override public boolean equals( Object o ) { + if( this==o ) return true; + if( !(o instanceof Ary ary) ) return false; + if( _len != ary._len ) return false; + if( _es == ary._es ) return true; + for( int i=0; i<_len; i++ ) + if( !(_es[i]==null ? (ary._es[i] == null) : _es[i].equals(ary._es[i])) ) + return false; + return true; + } + @Override public int hashCode( ) { + int sum=_len; + for( int i=0; i<_len; i++ ) + sum += _es[i]==null ? 0 : _es[i].hashCode(); + return sum; + } + +} diff --git a/chapter17b/src/main/java/com/seaofnodes/simple/GlobalCodeMotion.java b/chapter17b/src/main/java/com/seaofnodes/simple/GlobalCodeMotion.java new file mode 100644 index 00000000..eba99128 --- /dev/null +++ b/chapter17b/src/main/java/com/seaofnodes/simple/GlobalCodeMotion.java @@ -0,0 +1,238 @@ + package com.seaofnodes.simple; + +import com.seaofnodes.simple.IterPeeps.WorkList; +import com.seaofnodes.simple.node.*; +import com.seaofnodes.simple.type.*; +import java.util.*; + +public abstract class GlobalCodeMotion { + + // Arrange that the existing isCFG() Nodes form a valid CFG. The + // Node.use(0) is always a block tail (either IfNode or head of the + // following block). There are no unreachable infinite loops. + public static void buildCFG( StopNode stop ) { + schedEarly(); + Parser.SCHEDULED = true; + schedLate( stop); + } + + + // ------------------------------------------------------------------------ + // Visit all nodes in CFG Reverse Post-Order, essentially defs before uses + // (except at loops). Since defs are visited first - and hoisted as early + // as possible, when we come to a use we place it just after its deepest + // input. + private static void schedEarly() { + ArrayList rpo = new ArrayList<>(); + BitSet visit = new BitSet(); + _rpo_cfg(Parser.START, visit, rpo); + // Reverse Post-Order on CFG + for( int j=rpo.size()-1; j>=0; j-- ) { + CFGNode cfg = rpo.get(j); + cfg.loopDepth(); + for( Node n : cfg._inputs ) + _schedEarly(n,visit); + // In dead infinite loops, entire code blocks may be unreachable + // from below. Reach down from the CFG to their Phis so their + // inputs are scheduled too. + if( cfg instanceof RegionNode ) + for( Node phi : cfg._outputs ) + if( phi instanceof PhiNode ) + _schedEarly(phi,visit); + } + } + + // Post-Order of CFG + private static void _rpo_cfg(Node n, BitSet visit, ArrayList rpo) { + if( !(n instanceof CFGNode cfg) || visit.get(cfg._nid) ) + return; // Been there, done that + visit.set(cfg._nid); + for( Node use : cfg._outputs ) + _rpo_cfg(use,visit,rpo); + rpo.add(cfg); + } + + private static void _schedEarly(Node n, BitSet visit) { + if( n==null || visit.get(n._nid) ) return; // Been there, done that + assert !(n instanceof CFGNode); + visit.set(n._nid); + // Schedule inputs first, except Phis: following their backedges would + // enter a data cycle before its control has been scheduled. + for( Node def : n._inputs ) + if( def!=null && !(def instanceof PhiNode) ) + _schedEarly(def,visit); + // An existing edge 0 already supplies control (or a Phi/Proj binding). + if( n.in(0)==null ) { + // Schedule at deepest input + CFGNode early = Parser.START; // Maximally early, lowest idepth + for( int i=1; i early.idepth() ) + early = n.in(i).cfg0(); // Latest/deepest input + n.setDef(0,early); // First place this can go + } + } + + // ------------------------------------------------------------------------ + private static void schedLate( StopNode stop) { + CFGNode[] late = new CFGNode[Node.UID()]; + Node[] ns = new Node[Node.UID()]; + // Record Load NIDs at all their CFG block choices, then check against + // Store block choices to force a Load above an anti-dependent Store. + int[] anti = new int[Node.UID()]; + // Breadth-first scheduling + breadth(stop,ns,late,anti); + + // Copy the best placement choice into the control slot + for( int i=0; i work = new WorkList<>(); + work.push(stop); + Node n; + outer: + while( (n = work.pop()) != null ) { + assert late[n._nid]==null; // No double visit + // These I know the late schedule of, and need to set early for loops + if( n instanceof CFGNode cfg ) late[n._nid] = cfg.blockHead() ? cfg : cfg.cfg(0); + else if( n instanceof PhiNode phi ) late[n._nid] = phi.region(); + else if( n instanceof ProjNode && n.in(0) instanceof CFGNode cfg ) late[n._nid] = cfg; + else { + + // All uses done? + for( Node use : n._outputs ) + if( use!=null && late[use._nid]==null ) + continue outer; // Nope, await all uses done + + // Loads need their memory inputs' uses also done + if( n instanceof LoadNode ld ) + for( Node memuse : ld.antiDeps() ) + if( late[memuse._nid]==null ) + continue outer; + + // All uses done, schedule + _doSchedLate(n,ns,late,anti); + } + + // A use just finished; reconsider its inputs and waiting loads, + // even when the shared memory input was already scheduled. + for( Node def : n._inputs ) { + if( def==null ) continue; + if( late[def._nid]==null ) work.push(def); + wakeLoads(def,late,work,new BitSet()); + } + if( n instanceof LoopNode loop ) + for( Node phi : loop._outputs ) + if( phi instanceof PhiNode && late[phi._nid]==null ) + work.push(phi); + } + } + + private static void _doSchedLate(Node n, Node[] ns, CFGNode[] late, int[] anti) { + // Walk uses, gathering the LCA (Least Common Ancestor) of uses + CFGNode early = n.in(0) instanceof CFGNode cfg ? cfg : n.in(0).cfg0(); + assert early != null; + CFGNode lca = null; + for( Node use : n._outputs ) + if( use != null ) + lca = use_block(n,use, late).domLCA(lca,null); + + // Loads may need anti-dependencies, raising their LCA + if( n instanceof LoadNode load ) + lca = find_anti_dep(lca,load,early,late,anti); + + // Walk up from the LCA to the early, looking for best place. This is + // the lowest execution frequency, approximated by least loop depth and + // deepest control flow. + CFGNode best = lca; + lca = lca.idom(); // Already found best for starting LCA + for( ; lca != early.idom(); lca = lca.idom() ) + if( better(lca,best) ) + best = lca; + assert !(best instanceof IfNode); + ns [n._nid] = n; + late[n._nid] = best; + } + + // Block of use. Normally from late[] schedule, except for Phis, which go + // to the matching Region input. + private static CFGNode use_block(Node n, Node use, CFGNode[] late) { + if( !(use instanceof PhiNode phi) ) + return late[use._nid]; + CFGNode found=null; + for( int i=1; i best.idepth() || + best instanceof IfNode; + } + + // An allocation may consume a load's memory through a partial aggregate. + private static void wakeLoads(Node def, CFGNode[] late, WorkList work, BitSet visit) { + if( visit.get(def._nid) ) return; + visit.set(def._nid); + for( Node out : def._outputs ) + if( out instanceof LoadNode ld && late[ld._nid]==null ) work.push(ld); + if( def instanceof MemMergeNode ) + for( int i=1; iearly, flagging Load's block location choices + for( CFGNode cfg=lca; early!=null && cfg!=early.idom(); cfg = cfg.idom() ) + anti[cfg._nid] = load._nid; + // Walk load->mem uses, looking for Stores causing an anti-dep + for( Node mem : load.antiDeps() ) { + switch( mem ) { + case StoreNode st: + assert late[st._nid]!=null; + lca = anti_dep(load,late[st._nid],st.cfg0(),lca,st,anti); + break; + case NewNode st: + assert late[st._nid]!=null; + lca = anti_dep(load,late[st._nid],st.cfg0(),lca,st,anti); + break; + case PhiNode phi: + // Repeat anti-dep for matching Phi inputs. + // No anti-dep edges but may raise the LCA. + for( int i=1; i { + private static final com.seaofnodes.print.IRPrinter PRINT = + new com.seaofnodes.print.IRPrinter<>(new IRPrinter()); + @Override public String type(Node n) { return n._type==null ? "" : n._type.str(); } + @Override public String inputMark(Node n, Node def) { return n instanceof MemMergeNode && def instanceof MemMergeNode ? "^" : " "; } + @Override public Kind kind(Node n) { + if( n instanceof StartNode ) return Kind.START; + if( n instanceof StopNode ) return Kind.STOP; + if( n instanceof LoopNode ) return Kind.LOOP; + if( n instanceof RegionNode ) return Kind.REGION; + if( n instanceof PhiNode ) return Kind.PHI; + if( n instanceof ReturnNode ) return Kind.RETURN; + if( n instanceof ConstantNode ) return Kind.CONSTANT; + if( n instanceof CProjNode ) return Kind.CPROJ; + if( n instanceof ProjNode ) return n instanceof CFGNode ? Kind.CPROJ : Kind.PROJ; + if( n instanceof CFGNode ) return Kind.CTRL; + if( n instanceof MultiNode ) return Kind.MULTI; + return Kind.DATA; + } + @Override public int index(Node n) { + if( n instanceof ProjNode p ) return p._idx; + if( n instanceof CProjNode p ) return p._idx; + return n._nid; + } + + public static String prettyPrint(Node n, int depth) { return PRINT.prettyPrint(n,depth); } +} diff --git a/chapter17b/src/main/java/com/seaofnodes/simple/IterPeeps.java b/chapter17b/src/main/java/com/seaofnodes/simple/IterPeeps.java new file mode 100644 index 00000000..5a80698a --- /dev/null +++ b/chapter17b/src/main/java/com/seaofnodes/simple/IterPeeps.java @@ -0,0 +1,211 @@ +package com.seaofnodes.simple; + +import com.seaofnodes.simple.node.*; + +import java.util.Arrays; +import java.util.BitSet; +import java.util.Random; + +/** + * The IterPeeps runs after parsing. It iterates the peepholes to a fixed point + * so that no more peepholes apply. This should be linear because peepholes rarely + * (never?) increase code size. The graph should monotonically reduce in some + * dimension, which is usually size. It might also reduce in e.g. number of + * MulNodes or Load/Store nodes, swapping out more "expensive" Nodes for cheaper + * ones. + *
+ * The theoretical overall worklist is mindless just grabbing the next thing and + * doing it. If the graph changes, put the neighbors on the worklist. + *
+ * Lather, Rinse, Repeat until the worklist runs dry. + *

+ * The main issues we have to deal with: + * + *

    + *
  • Nodes have uses; replacing some set of Nodes with another requires more graph + * reworking. Not rocket science, but it can be fiddly. Its helpful to have a + * small set of graph munging utilities, and the strong invariant that the graph + * is stable and correct between peepholes. In our case `Node.subsume` does + * most of the munging, building on our prior stable Node utilities.
    • + * + *
  • Changing a Node also changes the graph "neighborhood". The neighbors need to + * be checked to see if THEY can also peephole, and so on. After any peephole + * or graph update we put a Nodes uses and defs on the worklist.
    • + * + *
  • Our strong invariant is that for all Nodes, either they are on the worklist + * OR no peephole applies. This invariant is easy to check, although expensive. + * Basically the normal "iterate peepholes to a fixed point" is linear, and this + * check is linear at each peephole step... so quadratic overall. Its a useful + * assert, but one we can disable once the overall algorithm is stable - and + * then turn it back on again when some new set of peepholes is misbehaving. + * The code for this is turned on in `IterPeeps.iterate` as `assert + * progressOnList(stop);`
    • + *
+ */ +public abstract class IterPeeps { + + private static final WorkList WORK = new WorkList<>(); + + public static N add( N n ) { + return (N)WORK.push(n); + } + + public static void addAll( Ary ary ) { + WORK.addAll(ary); + } + + /** + * Iterate peepholes to a fixed point + */ + public static StopNode iterate(StopNode stop) { + assert progressOnList(stop); + int cnt=0; + + Node n; + while( (n=WORK.pop()) != null ) { + if( n.isDead() ) continue; + cnt++; // Useful for debugging, searching which peephole broke things + var obs = Parser.PARSER == null ? null : Parser.PARSER._obs; + if( obs != null ) obs.before(n); + Node x = n.peepholeOpt(); + if( x != null ) { + if( x.isDead() ) { + if( obs != null ) obs.after(n, x, true); + continue; + } + // peepholeOpt can return brand-new nodes, needing an initial type set + if( x._type==null ) x.setType(x.compute()); + // Changes require neighbors onto the worklist + if( x != n || !(x instanceof ConstantNode) ) { + // All outputs of n (changing node) not x (prior existing node). + for( Node z : n._outputs ) WORK.push(z); + // Everybody gets a free "go again" in case they didn't get + // made in their final form. + WORK.push(x); + // If the result is not self, revisit all inputs (because + // there's a new user), and replace in the graph. + if( x != n ) { + for( Node z : n. _inputs ) WORK.push(z); + n.subsume(x); + } + } + // If there are distant neighbors, move to worklist + n.moveDepsToWorklist(); + assert progressOnList(stop); // Very expensive assert + } + if( n.isUnused() && !(n instanceof StopNode) ) + n.kill(); // Just plain dead + if( obs != null ) obs.after(n, x, true); + } + + return stop; + } + + // Visit ALL nodes and confirm the invariant: + // Either you are on the WORK worklist OR running `iter()` makes no progress. + + // This invariant ensures that no progress is missed, i.e., when the + // worklist is empty we have indeed done all that can be done. To help + // with debugging, the {@code assert} is broken out in a place where it is easy to + // stop if a change is found. + + // Also, the normal usage of `iter()` may attempt peepholes with distance + // neighbors and these should fail, but will then try to add dependencies + // {@link #Node.addDep} which is a side effect in an assert. The {@link + // #midAssert} is used to stop this side effect. + private static boolean MID_ASSERT; + public static boolean midAssert() { return MID_ASSERT; } + private static boolean progressOnList(Node stop) { + MID_ASSERT = true; + int old_cnt = Node.ITER_CNT, old_nop = Node.ITER_NOP_CNT; + Node changed = stop.walk( n -> { + Node m = n; + if( n.compute().isa(n._type) && (!n.iskeep() || n._nid<=5) ) { // Types must be forwards, even if on worklist + if( WORK.on(n) ) return null; + m = n.peepholeOpt(); + if( m==null ) return null; + } + System.err.println("BREAK HERE FOR BUG"); + return m; + }); + Node.ITER_CNT = old_cnt; Node.ITER_NOP_CNT = old_nop; + MID_ASSERT = false; + return changed==null; + } + + public static void reset() { + WORK.clear(); + } + + /** + * Classic WorkList, with a fast add/remove, dup removal, random pull. + * The Node's nid is used to check membership in the worklist. + */ + public static class WorkList { + + private Node[] _es; + private int _len; + private final BitSet _on; // Bit set if Node._nid is on WorkList + private final Random _R; // For randomizing pull from the WorkList + private final long _seed; + + /* Useful stat - how many nodes are processed in the post parse iterative opt */ + private long _totalWork = 0; + + WorkList() { this(123); } + WorkList(long seed) { + _es = new Node[1]; + _len=0; + _on = new BitSet(); + _seed = seed; + _R = new Random(); + _R.setSeed(_seed); + } + + /** + * Pushes a Node on the WorkList, ensuring no duplicates + * If Node is null it will not be added. + */ + public E push( E x ) { + if( x==null ) return null; + int idx = x._nid; + if( !_on.get(idx) ) { + _on.set(idx); + if( _len==_es.length ) + _es = Arrays.copyOf(_es,_len<<1); + _es[_len++] = x; + _totalWork++; + } + return x; + } + + public void addAll( Ary ary ) { + for( E n : ary ) + push(n); + } + + /** + * True if Node is on the WorkList + */ + boolean on( E x ) { return _on.get(x._nid); } + + /** + * Removes a random Node from the WorkList; null if WorkList is empty + */ + E pop() { + if( _len == 0 ) return null; + int idx = _R.nextInt(_len); + E x = (E)_es[idx]; + _es[idx] = _es[--_len]; // Compress array + _on.clear(x._nid); + return x; + } + + public void clear() { + _len = 0; + _on.clear(); + _R.setSeed(_seed); + _totalWork = 0; + } + } +} diff --git a/chapter17b/src/main/java/com/seaofnodes/simple/Parser.java b/chapter17b/src/main/java/com/seaofnodes/simple/Parser.java new file mode 100644 index 00000000..776aa91f --- /dev/null +++ b/chapter17b/src/main/java/com/seaofnodes/simple/Parser.java @@ -0,0 +1,1450 @@ +package com.seaofnodes.simple; + +import com.seaofnodes.graph.GraphObserver; + +import com.seaofnodes.simple.node.*; +import com.seaofnodes.simple.type.*; + +import java.util.*; + +/** + * The Parser converts a Simple source program to the Sea of Nodes intermediate + * representation directly in one pass. There is no intermediate Abstract + * Syntax Tree structure. + *

+ * This is a simple recursive descent parser. All lexical analysis is done here as well. + */ +public class Parser { + + // Current compilation context; the observer belongs to the parser. + public static Parser PARSER; + public GraphObserver _obs; + public int pos() { return _lexer._position; } + + + /** + * A Global Static, unique to each compilation. This is a public, so we + * can make constants everywhere without having to thread the StartNode + * through the entire parser and optimizer. + *

+ * To make the compiler multithreaded, this field will have to move into a TLS. + */ + public static StartNode START; + + public static ConstantNode ZERO; // Very common node, cached here + public static XCtrlNode XCTRL; // Very common node, cached here + + // Next available memory alias number + static int ALIAS; + + public StopNode STOP; + + // Debugger Printing. + public static boolean SCHEDULED; // True if debug printer can use schedule info + + // The Lexer. Thin wrapper over a byte[] buffer with a cursor. + private final Lexer _lexer; + + /** + * Current ScopeNode - ScopeNodes change as we parse code, but at any point of time + * there is one current ScopeNode. The reason the current ScopeNode can change is to do with how + * we handle branching. See {@link #parseIf()}. + *

+ * Each ScopeNode contains a stack of lexical scopes, each scope is a symbol table that binds + * variable names to Nodes. The top of this stack represents current scope. + *

+ * We keep a list of all ScopeNodes so that we can show them in graphs. + * @see #parseIf() + * @see #_xScopes + */ + public ScopeNode _scope; + + /** + * List of keywords disallowed as identifiers + */ + private static final HashSet KEYWORDS = new HashSet<>(){{ + add("bool"); + add("break"); + add("byte"); + add("continue"); + add("else"); + add("f32"); + add("f64"); + add("false"); + add("flt"); + add("i16"); + add("i32"); + add("i64"); + add("i8"); + add("if"); + add("int"); + add("new"); + add("null"); + add("return"); + add("struct"); + add("true"); + add("u1"); + add("u16"); + add("u32"); + add("u8"); + add("while"); + }}; + + + /** + * We clone ScopeNodes when control flows branch; it is useful to have + * a list of all active ScopeNodes for purposes of visualization of the SoN graph + */ + public final Stack _xScopes = new Stack<>(); + + ScopeNode _continueScope; + ScopeNode _breakScope; // Merge all the while-breaks here + + // Mapping from a type name to a Type. The string name matches + // `type.str()` call. No TypeMemPtrs are in here, because Simple does not + // have C-style '*ptr' references. + public static HashMap TYPES; + + // Mapping from a type name to the constructor for a Type. + public final HashMap INITS; + + + public Parser(String source, TypeInteger arg) { + PARSER = this; + Node.reset(); + IterPeeps.reset(); + SCHEDULED = false; + _lexer = new Lexer(source); + _scope = new ScopeNode(); + _continueScope = _breakScope = null; + START = new StartNode(arg); + STOP = new StopNode(source); + ZERO = con(0).keep(); + XCTRL= new XCtrlNode().peephole().keep(); + ALIAS = 2; // alias 0 for the control, 1 for memory + TYPES = defaultTypes(); + INITS = new HashMap<>(); + } + + public Parser(String source) { + this(source, TypeInteger.BOT); + } + + @Override + public String toString() { return _lexer.toString(); } + + public static HashMap defaultTypes() { + return new HashMap<>() {{ + put("bool",TypeInteger.U1 ); + put("byte",TypeInteger.U8 ); + put("f32" ,TypeFloat .B32); + put("f64" ,TypeFloat .BOT); + put("flt" ,TypeFloat .BOT); + put("i16" ,TypeInteger.I16); + put("i32" ,TypeInteger.I32); + put("i64" ,TypeInteger.BOT); + put("i8" ,TypeInteger.I8 ); + put("int" ,TypeInteger.BOT); + put("u1" ,TypeInteger.U1 ); + put("u16" ,TypeInteger.U16); + put("u32" ,TypeInteger.U32); + put("u8" ,TypeInteger.U8 ); + put("val" ,Type.TOP); // Marker type, indicates type inference + put("var" ,Type.BOTTOM); // Marker type, indicates type inference + }}; + } + + // Debugging utility to find a Node by index + public static Node find(int nid) { return START.find(nid); } + + private Node ctrl() { return _scope.ctrl(); } + private N ctrl(N n) { return _scope.ctrl(n); } + + public StopNode parse() { + _xScopes.push(_scope); + // Enter a new scope for the initial control and arguments + _scope.push(); + _scope.define(ScopeNode.CTRL, Type.CONTROL , false, new CProjNode(START, 0, ScopeNode.CTRL).peephole()); + _scope.define(ScopeNode.MEM0, TypeMem.BOT , false, new ProjNode(START, 1, ScopeNode.MEM0).peephole()); + _scope.define(ScopeNode.ARG0, TypeInteger.BOT, false, new ProjNode(START, 2, ScopeNode.ARG0).peephole()); + + // Parse whole program + parseBlock(false); + + if( ctrl()._type==Type.CONTROL ) + STOP.addReturn(new ReturnNode(ctrl(), ZERO, _scope).peephole()); + _scope.kill(); + _xScopes.pop(); + for( StructNode init : INITS.values() ) + init.unkeep().kill(); + INITS.clear(); + if (!_lexer.isEOF()) throw error("Syntax error, unexpected " + _lexer.getAnyNextToken()); + STOP.peephole(); + return STOP; + } + + /** + * Parses a block + * + * 

+     *     '{' statements '}'
+     *
+ * Does not parse the opening or closing '{}' + * @return a {@link Node} or {@code null} + */ + private Node parseBlock(boolean inCon) { + // Enter a new scope + _scope.push(inCon); + while (!peek('}') && !_lexer.isEOF()) + parseStatement(); + // Exit scope + _scope.pop(); + return null; + } + + /** + * Parses a statement + * + * 
+     *     returnStatement | declStatement | blockStatement | ifStatement | expressionStatement
+     *
+ * @return a {@link Node} or {@code null} + */ + private Node parseStatement() { + if( false ) return null; + else if (matchx("return") ) return parseReturn(); + else if (match ("{") ) return require(parseBlock(false),"}"); + else if (matchx("if") ) return parseIf(); + else if (matchx("while") ) return parseWhile(); + else if (matchx("for") ) return parseFor(); + else if (matchx("break") ) return parseBreak(); + else if (matchx("continue")) return parseContinue(); + else if (matchx("struct") ) return parseStruct(); + else if (matchx(";") ) return null; // Empty statement + // Declaration or normal assignment/expression + else return parseDeclarationStatement(); + } + + /** + * Parses a while statement + * + * 
+     *     while ( expression ) statement
+     *
+ * @return a {@link Node}, never {@code null} + */ + private Node parseWhile() { + require("("); + return parseLooping(false); + } + + + /** + * Parses a for statement + * + * 
+     *     for( var x=init; test; incr ) body
+     *
+ * @return a {@link Node}, never {@code null} + */ + private Node parseFor() { + // { var x=init,y=init,...; + // while( pred ) { + // body; + // next; + // } + // } + require("("); + _scope.push(); // Scope for the index variables + if( !match(";") ) // Can be empty init "for(;test;next) body" + parseDeclarationStatement(); // Non-empty init + Node rez = parseLooping(true); + _scope.pop(); // Exit index variable scope + return rez; + } + + // Shared by `for` and `while` + private Node parseLooping( boolean doFor ) { + + var savedContinueScope = _continueScope; + var savedBreakScope = _breakScope; + + // Loop region has two control inputs, the first is the entry + // point, and second is back edge that is set after loop is parsed + // (see end_loop() call below). Note that the absence of back edge is + // used as an indicator to switch off peepholes of the region and + // associated phis; see {@code inProgress()}. + + ctrl(new LoopNode(ctrl()).peephole()); // Note we set back edge to null here + + // At loop head, we clone the current Scope (this includes all + // names in every nesting level within the Scope). + // We create phis eagerly for all the names we find, see dup(). + + // Save the current scope as the loop head + ScopeNode head = _scope.keep(); + // Clone the head Scope to create a new Scope for the body. + // Create phis eagerly as part of cloning + _xScopes.push(_scope = _scope.dup(true)); // The true argument triggers creating phis + + // Parse predicate + var pred = peek(';') ? con(1) : parseAsgn(); + require( doFor ? ";" : ")" ); + + // IfNode takes current control and predicate + Node ifNode = new IfNode(ctrl(), pred.keep()).peephole(); + // Setup projection nodes + Node ifT = new CProjNode(ifNode. keep(), 0, "True" ).peephole().keep(); + Node ifF = new CProjNode(ifNode.unkeep(), 1, "False").peephole(); + + // for( ;;next ) body + int nextPos = -1, nextEnd = -1; + if( doFor ) { + // Skip the next expression and parse it later + nextPos = pos(); + skipAsgn(); + nextEnd = pos(); + require(")"); + } + + // Clone the body Scope to create the break/exit Scope which accounts for any + // side effects in the predicate. The break/exit Scope will be the final + // scope after the loop, and its control input is the False branch of + // the loop predicate. Note that body Scope is still our current scope. + ctrl(ifF); + _xScopes.push(_breakScope = _scope.dup()); + _breakScope.addGuards(ifF,pred,true); // Up-cast predicate + + // No continues yet + _continueScope = null; + + // Parse the true side, which corresponds to loop body + // Our current scope is the body Scope + ctrl(ifT.unkeep()); // set ctrl token to ifTrue projection + _scope.addGuards(ifT,pred.unkeep(),false); // Up-cast predicate + parseStatement(); // Parse loop body + _scope.removeGuards(ifT); + + // Merge the loop bottom into other continue statements + if (_continueScope != null) { + _continueScope = jumpTo(_continueScope); + _scope.kill(); + _scope = _continueScope; + } + + // Now append the next code onto the body code + if( doFor ) { + int old = pos(nextPos); + if( !peek(')') ) + parseAsgn(); + if( pos() != nextEnd ) + throw errorSyntax( "Unexpected code after expression" ); + pos(old); + } + + // The true branch loops back, so whatever is current _scope.ctrl gets + // added to head loop as input. endLoop() updates the head scope, and + // goes through all the phis that were created earlier. For each phi, + // it sets the second input to the corresponding input from the back + // edge. If the phi is redundant, it is replaced by its sole input. + var exit = _breakScope; + head.endLoop(_scope, exit); + head.unkeep().kill(); + + _xScopes.pop(); // Cleanup + _xScopes.pop(); // Cleanup + + _continueScope = savedContinueScope; + _breakScope = savedBreakScope; + + // At exit the false control is the current control, and + // the scope is the exit scope after the exit test. + _xScopes.pop(); + _xScopes.push(exit); + _scope = exit; + return _scope; + } + + private ScopeNode jumpTo(ScopeNode toScope) { + ScopeNode cur = _scope.dup(); + ctrl(XCTRL); // Kill current scope + // Prune nested lexical scopes that have depth > than the loop head + // We use _breakScope as a proxy for the loop head scope to obtain the depth + while( cur._lexSize.size() > _breakScope._lexSize.size() ) + cur.pop(); + // If this is a continue then first time the target is null + // So we just use the pruned current scope as the base for the + // "continue" + if( toScope == null ) + return cur; + // toScope is either the break scope, or a scope that was created here + assert toScope._lexSize.size() <= _breakScope._lexSize.size(); + toScope.ctrl(toScope.mergeScopes(cur).peephole()); + return toScope; + } + + private void checkLoopActive() { if (_breakScope == null) throw Parser.error("No active loop for a break or continue"); } + + private Node parseContinue() { checkLoopActive(); return (_continueScope = require(jumpTo( _continueScope ),";")); } + private Node parseBreak () { + checkLoopActive(); + // At the time of the break, and loop-exit conditions are only valid if + // they are ALSO valid at the break. It is the intersection of + // conditions here, not the union. + _breakScope.removeGuards(_breakScope.ctrl()); + _breakScope = require(jumpTo(_breakScope ),";"); + _breakScope.addGuards(_breakScope.ctrl(), null, false); + return _breakScope; + } + + // Look for an unbalanced `)`, skipping balanced + private Type skipAsgn() { + int paren=0; + while( true ) + // Next X char handles skipping complex comments + switch( _lexer.nextXChar() ) { + case Character.MAX_VALUE: + throw Utils.TODO(); + case ')': + if( --paren<0 ) + return posT(pos()-1); // Leave the `)` behind + break; + case '(': paren ++; break; + default: break; + } + } + + + /** + * Parses a statement + * + * 
+     *     if ( expression ) statement [else statement]
+     *
+ * @return a {@link Node}, never {@code null} + */ + private Node parseIf() { + // Parse predicate + require("("); + var pred = require(parseAsgn(), ")"); + return parseTrinary(pred,true,"else"); + } + + // Parse a conditional expression, merging results. + private Node parseTrinary( Node pred, boolean stmt, String fside ) { + pred.keep(); + + // IfNode takes current control and predicate + Node ifNode = new IfNode(ctrl(), pred).peephole(); + // Setup projection nodes + Node ifT = new CProjNode(ifNode. keep(), 0, "True" ).peephole().keep(); + Node ifF = new CProjNode(ifNode.unkeep(), 1, "False").peephole().keep(); + // In if true branch, the ifT proj node becomes the ctrl + // But first clone the scope and set it as current + int ndefs = _scope.nIns(); + ScopeNode fScope = _scope.dup(); // Duplicate current scope + fScope.ctrl(ifF); // The pending arm already starts at False + _xScopes.push(fScope); // For graph visualization we need all scopes + + // Parse the true side + ctrl(ifT.unkeep()); // set ctrl token to ifTrue projection + _scope.addGuards(ifT,pred,false); // Up-cast predicate + Node lhs = stmt ? parseStatement() : parseAsgn().keep(); // Parse true-side + _scope.removeGuards(ifT); + + ScopeNode tScope = _scope; + + // Parse the false side + _scope = fScope; // Restore scope, then parse else block if any + ifF.unkeep(); // fScope already owns the false control + // Up-cast predicate, even if not else clause, because predicate can + // remain true if the true clause exits: `if( !ptr ) return 0; return ptr.fld;` + _scope.addGuards(ifF,pred,true); + boolean doRHS = match(fside); + Node rhs = doRHS + ? (stmt ? parseStatement() : parseAsgn()) + : (stmt ? null : con(lhs._type.makeZero())); + _scope.removeGuards(ifF); + if( doRHS ) + fScope = _scope; + pred.unkeep(); + + // Check for `if(pred) int x=17;` + if( tScope.nIns() != ndefs || fScope.nIns() != ndefs ) + throw error("Cannot define a new name on one arm of an if"); + + // Check the trinary widening int/flt + if( !stmt ) { + rhs = widenInt( rhs, lhs._type ).keep(); + lhs = widenInt( lhs.unkeep(), rhs._type ).keep(); + rhs.unkeep(); + } + + // Merge results + _scope = tScope; + _xScopes.pop(); // Discard pushed from graph display + + RegionNode r = ctrl(tScope.mergeScopes(fScope)); + Node ret = stmt ? r : peep(new PhiNode("",lhs._type.meet(rhs._type),r,lhs.unkeep(),rhs)); + r.peephole(); + return ret; + } + + /** + * Parses a return statement; "return" already parsed. + * The $ctrl edge is killed. + * + * 
+     *     'return' expr ;
+     *
+ * @return an expression {@link Node}, never {@code null} + */ + private Node parseReturn() { + var expr = require(parseAsgn(), ";"); + Node ret = STOP.addReturn(new ReturnNode(ctrl(), expr, _scope).peephole()); + ctrl(XCTRL); // Kill control + return ret; + } + + + + /** Parse: [name '='] expr + */ + private Node parseAsgn() { + int old = pos(); + String name = _lexer.matchId(); + // Just a plain expression, no assignment. + // Distinguish `var==expr` from `var=expr` + if( name==null || KEYWORDS.contains(name) || !matchOpx('=','=') ) + { pos(old); return parseExpression(); } + + // Parse assignment expression + Node expr = parseAsgn(); + + // Final variable to update + ScopeNode.Var def = _scope.lookup(name); + if( def==null ) + throw error("Undefined name '" + name + "'"); + + // TOP fields are for late-initialized fields; these have never + // been written to, and this must be the final write. Other writes + // outside the constructor need to check the final bit. + if( _scope.in(def._idx)._type!=Type.TOP && def._final && !_scope.canInit(def) ) + throw error("Cannot reassign final '"+name+"'"); + + // Lift expression, based on type + Node lift = liftExpr(expr, def.type()); + // Update + _scope.update(name,lift); + // Return un-lifted expr + return expr; + } + + // Apply declared access permissions; widen floats and narrow integers. + // Early error if types do not match variable. + private Node liftExpr( Node expr, Type t ) { + assert !(expr._type instanceof TypeMemPtr tmp) || !tmp.isFRef(); + // Read-only access is deep; a fixed binding alone does not remove access. + if( t instanceof TypeMemPtr tmp && tmp.isFinal() ) { + expr = peep(new ReadOnlyNode(expr)); + } + // Auto-widen int to float + expr = widenInt( expr, t ); + // Auto-narrow wide ints to narrow ints + expr = zsMask(expr,t); + // Type is sane + if( !expr._type.isa(t) || !expr._type.accessISA(t) ) + throw error("Type " + expr._type.str() + " is not of declared type " + t.str()); + return expr; + } + + private Node widenInt( Node expr, Type t ) { + return expr._type instanceof TypeInteger && t instanceof TypeFloat + ? peep(new ToFloatNode(expr)) : expr; + } + + /** + * Parse declaration or expression statement + * declStmt = type var['=' exprAsgn][, var['=' exprAsgn]]* ';' | exprAsgn ';' + *

+ * exprAsgn = var '=' exprAsgn | expr + */ + private Node parseDeclarationStatement() { + Type t = type(); + if( t == null ) + return require(parseAsgn(),";"); + + // now parse var['=' asgnexpr] in a loop + Node n = parseDeclaration(t); + while( match(",") ) + n = parseDeclaration(t); + return require(n,";"); + } + + // The binding modifier sits immediately before the name. It never + // changes permissions on the referenced object. + private boolean bindingFinal(Type t) { + if( match("!") ) return false; + if( match("~") ) return true; + return t==Type.TOP || t instanceof TypeMemPtr; + } + + /** Parse final: [!|~]var['=' asgn] + */ + private Node parseDeclaration(Type t) { + assert t!=null; + // Has var/val instead of a user-declared type + boolean inferType = t==Type.TOP || t==Type.BOTTOM; + boolean xfinal = bindingFinal(t); + String name = requireId(); + + // Optional initializing expression follows + Node expr; + if( match("=") ) { + expr = parseAsgn(); + // var/val, then type comes from expression + if( inferType ) + t = expr._type instanceof TypeMemPtr ptr ? ptr.makeFrom(true) : expr._type.glb(); + + } else { + if( inferType && !_scope.inCon() ) + throw errorSyntax("=expression"); + expr = con(xfinal && !(t instanceof TypeMemPtr) ? Type.TOP : t.makeInit()); + } + + // Lift expression, based on type + Node lift = liftExpr(expr, t); + + // Define a new name, + if( !_scope.define(name,t,xfinal,lift) ) + throw error("Redefining name '" + name + "'"); + return null; + } + + + + /** + * Parse a struct declaration, and return the following statement. + * Only allowed in top level scope. + * Structs cannot be redefined. + * + * @return The statement following the struct + */ + private Node parseStruct() { + if (_xScopes.size() > 1) throw errorSyntax("struct declarations can only appear in top level scope"); + String typeName = requireId(); + Type t = TYPES.get(typeName); + if( t!=null && !(t instanceof TypeMemPtr tmp && tmp.isFRef() ) ) + throw errorSyntax("struct '" + typeName + "' cannot be redefined"); + + // A Block scope parse, and inspect the scope afterward for fields. + _scope.push(true); + _xScopes.push(_scope); + require("{"); + while (!peek('}') && !_lexer.isEOF()) + parseStatement(); + + // Grab the declarations and build fields and a Struct + int lexlen = _scope._lexSize.last(); + int varlen = _scope._vars._len; + StructNode s = new StructNode(); + Field[] fs = new Field[varlen-lexlen]; + for( int i=lexlen; i + * expr : bitwise [? expr [: expr]] + * + * @return an expression {@link Node}, never {@code null} + */ + private Node parseExpression() { + Node expr = parseBitwise(); + return match("?") ? parseTrinary(expr,false,":") : expr; + } + + /** + * Parse an bitwise expression + * + * 

+     *     bitwise : compareExpr (('&' | '|' | '^') compareExpr)*
+     *
+ * @return a bitwise expression {@link Node}, never {@code null} + */ + private Node parseBitwise() { + Node lhs = parseComparison(); + while( true ) { + if( false ) ; + else if( match("&") ) lhs = new AndNode(lhs,null); + else if( match("|") ) lhs = new OrNode(lhs,null); + else if( match("^") ) lhs = new XorNode(lhs,null); + else break; + lhs.setDef(2,parseComparison()); + lhs = peep(lhs); + } + return lhs; + } + + /** + * Parse an expression of the form: + * + * 
+     *     expr : additiveExpr op additiveExpr
+     *
+ * @return an comparator expression {@link Node}, never {@code null} + */ + private Node parseComparison() { + var lhs = parseShift(); + while( true ) { + int idx=0; boolean negate=false; + // Test for any local nodes made, and "keep" lhs during peepholes + if( false ) ; + else if( match("==") ) { idx=2; lhs = new BoolNode.EQ(lhs, null); } + else if( match("!=") ) { idx=2; lhs = new BoolNode.EQ(lhs, null); negate=true; } + else if( match("<=") ) { idx=2; lhs = new BoolNode.LE(lhs, null); } + else if( match("<" ) ) { idx=2; lhs = new BoolNode.LT(lhs, null); } + else if( match(">=") ) { idx=1; lhs = new BoolNode.LE(null, lhs); } + else if( match(">" ) ) { idx=1; lhs = new BoolNode.LT(null, lhs); } + else break; + // Peepholes can fire, but lhs is already "hooked", kept alive + lhs.setDef(idx,parseShift()); + lhs = peep(lhs.widen()); + if( negate ) // Extra negate for != + lhs = peep(new NotNode(lhs)); + } + return lhs; + } + + /** + * Parse an additive expression + * + * 
+     *     shiftExpr : additiveExpr (('<<' | '>>' | '>>>') additiveExpr)*
+     *
+ * @return a shift expression {@link Node}, never {@code null} + */ + private Node parseShift() { + Node lhs = parseAddition(); + while( true ) { + if( false ) ; + else if( match("<<") ) lhs = new ShlNode(lhs,null); + else if( match(">>>")) lhs = new ShrNode(lhs,null); + else if( match(">>") ) lhs = new SarNode(lhs,null); + else break; + lhs.setDef(2,parseAddition()); + lhs = peep(lhs.widen()); + } + return lhs; + } + + /** + * Parse an additive expression + * + * 
+     *     additiveExpr : multiplicativeExpr (('+' | '-') multiplicativeExpr)*
+     *
+ * @return an add expression {@link Node}, never {@code null} + */ + private Node parseAddition() { + Node lhs = parseMultiplication(); + while( true ) { + if( false ) ; + else if( match("+") ) lhs = new AddNode(lhs,null); + else if( match("-") ) lhs = new SubNode(lhs,null); + else break; + lhs.setDef(2,parseMultiplication()); + lhs = peep(lhs.widen()); + } + return lhs; + } + + /** + * Parse an multiplicativeExpr expression + * + * 
+     *     multiplicativeExpr : unaryExpr (('*' | '/') unaryExpr)*
+     *
+ * @return a multiply expression {@link Node}, never {@code null} + */ + private Node parseMultiplication() { + var lhs = parseUnary(); boolean mul; + while( true ) { + if( false ) ; + else if( match("*") ) lhs = new MulNode(lhs,null); + else if( match("/") ) lhs = new DivNode(lhs,null); + else break; + lhs.setDef(2,parseUnary()); + lhs = peep(lhs.widen()); + } + return lhs; + } + + /** + * Parse a unary minus expression. + * + * 
+     *     unaryExpr : ('-') unaryExpr | '!') unaryExpr | postfixExpr | primaryExpr | '--' Id | '++' Id
+     *
+ * @return a unary expression {@link Node}, never {@code null} + */ + private Node parseUnary() { + // Pre-dec/pre-inc + int old = pos(); + if( match("--") || match("++") ) { + int delta = _lexer.peek(-1)=='+' ? 1 : -1; // Pre vs post + String name = _lexer.matchId(); + if( name!=null ) { + ScopeNode.Var n = _scope.lookup(name); + if( n != null ) { + if( n._final ) + throw error("Cannot reassign final '"+n._name+"'"); + Node expr = zsMask(peep(new AddNode(_scope.in(n),con(delta))),n.type()); + _scope.update(n,expr); + return expr; + } + } + // Reset, try again + pos(old); + } + if (match("-")) return peep(new MinusNode(parseUnary()).widen()); + if (match("!")) return peep(new NotNode(parseUnary())); + return parsePostfix(parsePrimary()); + } + + /** + * Parse a primary expression: + * + * 
+     *     primaryExpr : integerLiteral | true | false | null | new Type | '(' expression ')' | Id['++','--']
+     *
+ * @return a primary {@link Node}, never {@code null} + */ + private Node parsePrimary() { + if( _lexer.isNumber(_lexer.peek()) ) return parseLiteral(); + if( matchx("true" ) ) return con(1); + if( matchx("false") ) return ZERO; + if( matchx("null" ) ) return con(TypeMemPtr.NULLPTR); + if( match("(") ) return require(parseAsgn(), ")"); + if( matchx("new" ) ) return alloc(); + // Expect an identifier now + ScopeNode.Var n = requireLookupId("an identifier or expression"); + Node rvalue = _scope.in(n); + if( rvalue._type == Type.BOTTOM ) + throw error("Cannot read uninitialized field '"+n._name+"'"); + // Check for assign-update, x += e0; + char ch = _lexer.matchOperAssign(); + if( ch==0 ) return rvalue; + if( n._final ) + throw error("Cannot reassign final '"+n._name+"'"); + Node op = switch(ch) { + case '+' -> new AddNode(rvalue,null); + case '-' -> new SubNode(rvalue,null); + case '*' -> new MulNode(rvalue,null); + case '/' -> new DivNode(rvalue,null); + case '&' -> new AndNode(rvalue,null); + case '|' -> new OrNode(rvalue,null); + case '^' -> new XorNode(rvalue,null); + case Lexer.SHL -> new ShlNode(rvalue,null); + case Lexer.SAR -> new SarNode(rvalue,null); + case Lexer.SHR -> new ShrNode(rvalue,null); + case 1 -> new AddNode(rvalue,con( 1)); + case (char)-1 -> new AddNode(rvalue,con(-1)); + default -> throw Utils.TODO(); + }; + // Return pre-value (x+=1) or post-value (x++) + boolean pre = op.in(2)==null; + // Parse RHS argument as needed + if( pre ) + { op.keep().setDef(2,parseAsgn()); op.unkeep(); } + else rvalue.keep(); // Keep post-value across peeps + op = zsMask(peep(op),n.type()); + _scope.update(n,op); + return pre ? op : rvalue.unkeep(); + } + + ScopeNode.Var requireLookupId(String msg) { + String id = _lexer.matchId(); + if( id == null || KEYWORDS.contains(id) ) + throw errorSyntax(msg); + ScopeNode.Var n = _scope.lookup(id); + if( n==null ) + throw error("Undefined name '" + id + "'"); + return n; + } + + /** + Parse an allocation + */ + private Node alloc() { + Type t = type(); + if( t==null ) throw error("Expected a type"); + // Parse ary[ length_expr ] + if( match("[") ) { + Node len = parseAsgn(); + if( !(len._type instanceof TypeInteger) ) + throw error("Cannot allocate an array with length "+len._type); + require("]"); + TypeMemPtr tmp = typeAry(t); + return newArray(tmp._obj,len); + } + + if( !(t instanceof TypeMemPtr tmp) ) + throw error("Cannot allocate a "+t.str()); + + // Parse new struct { default_initialization } + StructNode s = INITS.get(tmp._obj._name); + if( s==null ) throw error("Unknown struct type '" + tmp._obj._name + "'"); + + Field[] fs = s._ts._fields; + // if the object is fully initialized, we can skip a block here. + // Check for constructor block: + boolean hasConstructor = match("{"); + Ary init=s._inputs; int idx=0; + if( hasConstructor ) { + idx = _scope.nIns(); + // Push a scope, and pre-assign all struct fields. + _scope.push(); + for( int i=0; i init ) { + Field[] fs = obj._fields; + if( fs==null ) + throw error("Unknown struct type '" + obj._name + "'"); + Node prior = mem().keep(); + MemMergeNode input = new MemMergeNode(null); + for( Field f : fs ) input.alias(f._alias,prior); + // Constructor values follow control, memory, and allocation size. + Node[] ns = new Node[3+fs.length]; + ns[0] = ctrl(); + ns[1] = input.peephole(); + ns[2] = size; + for( int i=0; i ALTMP = new Ary<>(Node.class); + private Node newArray(TypeStruct ary, Node len) { + int base = ary.aryBase (); + int scale= ary.aryScale(); + Node size = peep(new AddNode(con(base),peep(new ShlNode(len.keep(),con(scale))))); + ALTMP.clear(); ALTMP.add(len.unkeep()); ALTMP.add(con(ary._fields[1]._type.makeInit())); + return newStruct(ary,size,0,ALTMP); + } + + // Memory is one hidden SSA variable, including across branches and loops. + private Node mem() { return _scope.mem(); } + private void mem(Node n) { _scope.mem(n); } + + private void store(String name, int alias, Type glb, Node ptr, Node off, Node val, boolean init, Node ctrl) { + if( !init && ptr._type instanceof TypeMemPtr view && view._ro && ctrl()._type!=Type.XCONTROL ) + throw error("Cannot modify final field '"+name+"'"); + Node prior = mem().keep(); + Node st = new StoreNode(name,alias,glb,prior,ptr,off,val,init); + st.setDef(0,ctrl); + st = st.peephole(); + mem(new MemMergeNode(prior,alias,st).peephole()); + prior.unkeep(); + } + + /** + * Parse postfix expression. For now this is just a field + * expression, but in future could be array index too. + * + * 
+     *     expr ('.' IDENTIFIER)* [ = expr ]
+     *     expr #
+     *     expr ('[' expr ']')* = [ = expr ]
+     *
+ */ + private Node parsePostfix(Node expr) { + String name = null; + if( match(".") ) name = requireId(); + else if( match("#") ) name = "#"; + else if( match("[") ) name = "[]"; + else return expr; // No postfix + + // Sanity check expr for being a reference + if( !(expr._type instanceof TypeMemPtr ptr) ) + throw error("Expected reference but got " + expr._type.str()); + + // Happens when parsing known dead code, which often has other typing + // issues. Since the code is dead, possibly due to inlining, lets not + // spoil the user experience with error messages. + if( ctrl()._type==Type.XCONTROL ) + // Exit out via parsing the trailing expression + return matchOpx('=','=') ? parseAsgn() : parsePostfix(con(Type.TOP)); + + // Sanity check field name for existing + TypeMemPtr tmp = (TypeMemPtr)TYPES.get(ptr._obj._name); + if( tmp == null ) throw error("Accessing unknown field '" + name + "' from '" + ptr + "'"); + TypeStruct base = ptr._obj.isAry() ? ptr._obj : tmp._obj; + int fidx = base.find(name); + if( fidx == -1 ) throw error("Accessing unknown field '" + name + "' from '" + ptr.str() + "'"); + + // Get field type and layout offset from base type and field index fidx + Field f = base._fields[fidx]; // Field from field index + Type tf = f._type; + if( tf instanceof TypeMemPtr ftmp && ftmp.isFRef() ) + tf = ftmp.makeFrom(((TypeMemPtr)(TYPES.get(ftmp._obj._name)))._obj); + + expr.keep(); + // Field offset; fixed for structs, computed for arrays + Node off = (name.equals("[]") // If field is an array body + // Array index math + ? peep(new AddNode(con(base.aryBase()),peep(new ShlNode(require(parseAsgn(),"]"),con(base.aryScale()))))) + // Struct field offsets are hardwired + : con(base.offset(fidx))).keep(); + + // Disambiguate "obj.fld==x" boolean test from "obj.fld=x" field assignment + if( matchOpx('=','=') ) { + Node val = parseAsgn().keep(); + Node lift = liftExpr( val, tf ); + + store(name,f._alias,tf,expr.unkeep(),off.unkeep(),lift,false,base.isAry() ? ctrl() : null); + return val.unkeep(); // "obj.a = expr" returns the expression while updating memory + } + + Node load = new LoadNode(name, f._alias, (tf instanceof TypeMemPtr ? tf : tf.glb()), mem(), expr, off); + // Arrays include control, as a proxy for a safety range check + // Structs don't need this; they only need a NPE check which is + // done via the type system. + if( base.isAry() ) load.setDef(0,ctrl()); + load = peep(load); + + // ary[idx]++ or ptr.fld++ + if( matchx("++") || matchx("--") ) { + if( f._final && !f._fname.equals("[]") ) + throw error("Cannot reassign final '"+f._fname+"'"); + Node inc = peep(new AddNode(load,con( _lexer.peek(-1)=='+' ? 1 : -1))); + Node val = zsMask(inc,tf); + store(name,f._alias,tf,expr.unkeep(),off,val,false,base.isAry() ? ctrl() : null); + // And use the original loaded value as the result + } else expr.unkill(); + off.unkill(); + + return parsePostfix(load); + } + + + // zero/sign extend. "i" is limited to either classic unsigned (min==0) or + // classic signed (min=minus-power-of-2); max=power-of-2-minus-1. + private Node zsMask(Node val, Type t ) { + if( !(val._type instanceof TypeInteger tval && t instanceof TypeInteger t0 && !tval.isa(t0)) ) { + if( !(val._type instanceof TypeFloat tval && t instanceof TypeFloat t0 && !tval.isa(t0)) ) + return val; + // Float rounding + return peep(new RoundF32Node(val)); + } + if( t0._min==0 ) // Unsigned + return peep(new AndNode(val,con(t0._max))); + // Signed extension + int shift = Long.numberOfLeadingZeros(t0._max)-1; + Node shf = con(shift); + if( shf._type==TypeInteger.ZERO ) + return val; + return peep(new SarNode(peep(new ShlNode(val,shf.keep())),shf.unkeep())); + } + + + /** + * Parse integer literal + * + * 
+     *     integerLiteral: [1-9][0-9]* | [0]
+     *     floatLiteral: [digits].[digits]?[e [digits]]?
+     *
+ */ + private ConstantNode parseLiteral() { return con(_lexer.parseNumber()); } + public static Node con( long con ) { return con(TypeInteger.constant(con)); } + public static ConstantNode con( Type t ) { return (ConstantNode)new ConstantNode(t).peephole(); } + public Node peep( Node n ) { + // Peephole, then improve with lexically scoped guards + return _scope.upcastGuard(n.peephole()); + } + + ////////////////////////////////// + // Utilities for lexical analysis + + // Return true and skip if "syntax" is next in the stream. + private boolean match (String syntax) { return _lexer.match (syntax); } + // Match must be "exact", not be followed by more id letters + private boolean matchx(String syntax) { return _lexer.matchx(syntax); } + private boolean matchOpx(char c0, char c1) { return _lexer.matchOpx(c0,c1); } + // Return true and do NOT skip if 'ch' is next + private boolean peek(char ch) { return _lexer.peek(ch); } + private boolean peekIsId() { return _lexer.peekIsId(); } + + private int pos(int pos) { + int old = _lexer._position; + _lexer._position = pos; + return old; + } + private Type posT(int pos) { _lexer._position = pos; return null; } + + // Require and return an identifier + private String requireId() { + String id = _lexer.matchId(); + if (id != null && !KEYWORDS.contains(id) ) return id.intern(); + throw error("Expected an identifier, found '"+id+"'"); + } + + private String matchId() { + int old = pos(); + String id = _lexer.matchId(); + if( id==null ) return null; + if( !KEYWORDS.contains(id) ) return id; + pos(old); + return null; + } + + // Require an exact match + private Parser require(String syntax) { require(null, syntax); return this; } + private N require(N n, String syntax) { + if (match(syntax)) return n; + throw errorSyntax(syntax); + } + + RuntimeException errorSyntax(String syntax) { + return error("Syntax error, expected " + syntax + ": " + _lexer.getAnyNextToken()); + } + + public static RuntimeException error( String errorMessage ) { + return new RuntimeException(errorMessage); + } + + //////////////////////////////////// + // Lexer components + + private static class Lexer { + + // Input buffer; an array of text bytes read from a file or a string + private final byte[] _input; + // Tracks current position in input buffer + private int _position = 0; + + /** + * Record the source text for lexing + */ + public Lexer(String source) { + this(source.getBytes()); + } + + /** + * Direct from disk file source + */ + public Lexer(byte[] buf) { + _input = buf; + } + + // Very handy in the debugger, shows the unparsed program + @Override + public String toString() { + return new String(_input, _position, _input.length - _position); + } + + // True if at EOF + private boolean isEOF() { + return _position >= _input.length; + } + + // Peek next character, or report EOF + private char peek() { + return isEOF() ? Character.MAX_VALUE // Special value that causes parsing to terminate + : (char) _input[_position]; + } + // Just crash if misused + public byte peek(int off) { return _input[_position+off]; } + + private char nextChar() { + char ch = peek(); + _position++; + return ch; + } + + // True if a white space + private boolean isWhiteSpace() { + return peek() <= ' '; // Includes all the use space, tab, newline, CR + } + + /** + * Return the next non-white-space character + */ + private void skipWhiteSpace() { + while( true ) { + if( isWhiteSpace() ) _position++; + // Skip // to end of line + else if( _position+2 < _input.length && + _input[_position ] == '/' && + _input[_position+1] == '/') { + _position += 2; + while( !isEOF() && _input[_position] != '\n' ) _position++; + } else break; + } + } + + // Next non-white-space character, or EOF + public char nextXChar() { skipWhiteSpace(); return nextChar(); } + + // Return true, if we find "syntax" after skipping white space; also + // then advance the cursor past syntax. + // Return false otherwise, and do not advance the cursor. + boolean match(String syntax) { + skipWhiteSpace(); + int len = syntax.length(); + if (_position + len > _input.length) return false; + for (int i = 0; i < len; i++) + if ((char) _input[_position + i] != syntax.charAt(i)) + return false; + _position += len; + return true; + } + + // Match must be exact and not followed by more ID characters. + // Prevents identifier "ifxy" from matching an "if" statement. + boolean matchx(String syntax) { + if( !match(syntax) ) return false; + if( !isIdLetter(peek()) ) return true; + _position -= syntax.length(); + return false; + } + boolean matchOpx(char c0, char c1) { + skipWhiteSpace(); + if( _position+1 >= _input.length || _input[_position]!=c0 || _input[_position+1]==c1 ) + return false; + _position++; + return true; + } + + private boolean peek(char ch) { + skipWhiteSpace(); + return peek()==ch; + } + + boolean peekIsId() { + skipWhiteSpace(); + return isIdStart(peek()); + } + + // Return an identifier or null + String matchId() { + return peekIsId() ? parseId() : null; + } + + // Used for errors + String getAnyNextToken() { + if (isEOF()) return ""; + if (isIdStart(peek())) return parseId(); + if (isNumber(peek())) return parseNumberString(); + if (isPunctuation(peek())) return parsePunctuation(); + return String.valueOf(peek()); + } + + + boolean isNumber(char ch) {return Character.isDigit(ch);} + + // Return a constant Type, either TypeInteger or TypeFloat + private Type parseNumber() { + int old = _position; + int len = isLongOrDouble(); + if( len > 0 ) { + if( len > 1 && _input[old]=='0' ) + throw error("Syntax error: integer values cannot start with '0'"); + return TypeInteger.constant(Long.parseLong(new String(_input,old,len))); + } + return TypeFloat.constant(Double.parseDouble(new String(_input,old,-len))); + } + private String parseNumberString() { + int old = _position; + int len = Math.abs(isLongOrDouble()); + _position += len; + return new String(_input,old,len); + } + + // Return +len that ends a long + // Return -len that ends a double + private int isLongOrDouble() { + int old = _position; + char c; + while( Character.isDigit(c=nextChar()) ) ; + if( !(c=='e' || c=='.') ) + return --_position - old; + while( Character.isDigit(c=nextChar()) || c=='e' || c=='.' ) ; + return -(--_position - old); + } + + // First letter of an identifier + private boolean isIdStart(char ch) { + return Character.isAlphabetic(ch) || ch == '_'; + } + + // All characters of an identifier, e.g. "_x123" + private boolean isIdLetter(char ch) { + return Character.isLetterOrDigit(ch) || ch == '_'; + } + + private String parseId() { + int start = _position; + while (isIdLetter(nextChar())) ; + return new String(_input, start, --_position - start); + } + + // + private boolean isPunctuation(char ch) { + return "=;[]<>()+-/*&|^".indexOf(ch) != -1; + } + + private String parsePunctuation() { + int start = _position; + return new String(_input, start, 1); + } + + // Next oper= character, or 0. + // As a convenience, mark "++" as a char 1 and "--" as char -1 (65535) + // Disallow e.g. "arg--1" which should parse as "arg - -1" + // Distinct tags for the multi-character compound operators. + static final char SHL = 2, SAR = 3, SHR = 4; + + public char matchOperAssign() { + skipWhiteSpace(); + if( match("<<=" ) ) return SHL; + if( match(">>>=") ) return SHR; + if( match(">>=" ) ) return SAR; + if( _position+2 >= _input.length ) return 0; + char ch0 = (char)_input[_position]; + if( "+-/*&|^".indexOf(ch0) == -1 ) return 0; + char ch1 = (char)_input[_position+1]; + if( ch1 == '=' ) { _position += 2; return ch0; } + if( isIdLetter((char)_input[_position+2]) ) return 0; + if( ch0 == '+' && ch1 == '+' ) { _position += 2; return (char) 1; } + if( ch0 == '-' && ch1 == '-' ) { _position += 2; return (char)-1; } + return 0; + } + } +} diff --git a/chapter17b/src/main/java/com/seaofnodes/simple/Utils.java b/chapter17b/src/main/java/com/seaofnodes/simple/Utils.java new file mode 100644 index 00000000..1346c3ea --- /dev/null +++ b/chapter17b/src/main/java/com/seaofnodes/simple/Utils.java @@ -0,0 +1,53 @@ +package com.seaofnodes.simple; + +import java.util.ArrayList; + +public class Utils { + public static RuntimeException TODO() { return TODO("Not yet implemented"); } + public static RuntimeException TODO(String msg) { return new RuntimeException(msg); } + + /** + * Fast, constant-time, element removal. Does not preserve order + * + * @param array ArrayList to modify + * @param i element to be removed + * @return element removed + */ + public static void del(ArrayList array, int i) { + E last = array.removeLast(); + if (i < array.size()) array.set(i, last); + } + + /** + * Search a list for an element by reference + * + * @param ary List to search in + * @param x Object to be searched + * @return >= 0 on success, -1 on failure + */ + public static int find( ArrayList ary, E x ) { + for( int i=0; i= 0 on success, -1 on failure + */ + public static int find( E[] ary, E x ) { + for( int i=0; i>>n); } + + // Fold a 64bit hash into 32 bits + public static int fold( long x ) { return (int)((x>>32) ^ x); } +} diff --git a/chapter17b/src/main/java/com/seaofnodes/simple/node/AddFNode.java b/chapter17b/src/main/java/com/seaofnodes/simple/node/AddFNode.java new file mode 100644 index 00000000..fd713156 --- /dev/null +++ b/chapter17b/src/main/java/com/seaofnodes/simple/node/AddFNode.java @@ -0,0 +1,37 @@ +package com.seaofnodes.simple.node; + + +import com.seaofnodes.simple.type.Type; +import com.seaofnodes.simple.type.TypeFloat; + + +public class AddFNode extends Node { + public AddFNode(Node lhs, Node rhs) { super(null, lhs, rhs); } + + @Override public String label() { return "AddF"; } + + @Override protected String format() { return "(%1+%2)"; } + + @Override + public Type compute() { + if (in(1)._type instanceof TypeFloat i0 && + in(2)._type instanceof TypeFloat i1) { + if (i0.isConstant() && i1.isConstant()) + return TypeFloat.constant(i0.value()+i1.value()); + } + return in(1)._type.meet(in(2)._type); + } + + @Override + public Node idealize() { + Node lhs = in(1); + Type t2 = in(2)._type; + + // Add of 0. + if ( t2.isConstant() && t2 instanceof TypeFloat i && i.value()==0 ) + return lhs; + + return null; + } + @Override Node copy(Node lhs, Node rhs) { return new AddFNode(lhs,rhs); } +} diff --git a/chapter17b/src/main/java/com/seaofnodes/simple/node/AddNode.java b/chapter17b/src/main/java/com/seaofnodes/simple/node/AddNode.java new file mode 100644 index 00000000..5eb0b0a3 --- /dev/null +++ b/chapter17b/src/main/java/com/seaofnodes/simple/node/AddNode.java @@ -0,0 +1,186 @@ +package com.seaofnodes.simple.node; + + +import com.seaofnodes.simple.type.*; + + +public class AddNode extends Node { + public AddNode(Node lhs, Node rhs) { super(null, lhs, rhs); } + + @Override public String label() { return "Add"; } + + @Override protected String format() { return "(%1+%2)"; } + + + @Override + public Type compute() { + Type t1 = in(1)._type, t2 = in(2)._type; + if( t1.isHigh() || t2.isHigh() ) + return TypeInteger.TOP; + if( t1 instanceof TypeInteger i1 && + t2 instanceof TypeInteger i2 ) { + if (i1.isConstant() && i2.isConstant()) + return TypeInteger.constant(i1.value()+i2.value()); + // Fold ranges like {0-1} + {2-3} into {2-4}. + if( !overflow(i1._min,i2._min) && + !overflow(i1._max,i2._max) ) + return TypeInteger.make(i1._min+i2._min,i1._max+i2._max); + } + return TypeInteger.BOT; + } + + static boolean overflow( long x, long y ) { + if( (x ^ y ) < 0 ) return false; // unequal signs, never overflow + return (x ^ (x + y)) < 0; // sum has unequal signs, so overflow + } + @Override + public Node idealize () { + Node lhs = in(1); + Node rhs = in(2); + if( rhs.err() != null ) return null; + Type t2 = rhs._type; + + // Add of 0. We do not check for (0+x) because this will already + // canonicalize to (x+0) + if( t2 instanceof TypeInteger i && i.isConstant() && i.value()==0 ) + return lhs; + + // Add of same to a multiply by 2 + if( lhs==rhs ) + return new MulNode(lhs,new ConstantNode(TypeInteger.constant(2)).peephole()); + + // Goal: a left-spine set of adds, with constants on the rhs (which then fold). + + // Move non-adds to RHS + if( !(lhs instanceof AddNode) && rhs instanceof AddNode ) + return swap12(); + + // x+(-y) becomes x-y + if( rhs instanceof MinusNode minus ) + return new SubNode(lhs,minus.in(1)); + + // Now we might see (add add non) or (add non non) or (add add add) but never (add non add) + + // Do we have x + (y + z) ? + // Swap to (x + y) + z + // Rotate (add add add) to remove the add on RHS + if( rhs instanceof AddNode add ) + return new AddNode(new AddNode(lhs,add.in(1)).peephole(), add.in(2)); + + // Now we might see (add add non) or (add non non) but never (add non add) nor (add add add) + if( !(lhs instanceof AddNode) ) + // Rotate; look for (add (phi cons) con/(phi cons)) + return spine_cmp(lhs,rhs,this) ? swap12() : phiCon(this,true); + + // Now we only see (add add non) + + // Dead data cycle; comes about from dead infinite loops. Do nothing, + // the loop will peep as dead after a bit. + if( lhs.in(1) == lhs ) + return null; + + // Do we have (x + con1) + con2? + // Replace with (x + (con1+con2) which then fold the constants + // lhs.in(2) is con1 here + // If lhs.in(2) is not a constant, we add ourselves as a dependency + // because if it later became a constant then we could make this + // transformation. + if( lhs.in(2).addDep(this)._type.isConstant() && rhs._type.isConstant() ) + return new AddNode(lhs.in(1),new AddNode(lhs.in(2),rhs).peephole()); + + + // Do we have ((x + (phi cons)) + con) ? + // Do we have ((x + (phi cons)) + (phi cons)) ? + // Push constant up through the phi: x + (phi con0+con0 con1+con1...) + Node phicon = phiCon(this,true); + if( phicon!=null ) return phicon; + + // Now we sort along the spine via rotates, to gather similar things together. + + // Do we rotate (x + y) + z + // into (x + z) + y ? + if( spine_cmp(lhs.in(2),rhs,this) ) + return new AddNode(new AddNode(lhs.in(1),rhs).peephole(),lhs.in(2)); + + return null; + } + + // Rotation is only valid for associative ops, e.g. Add, Mul, And, Or, Xor. + // Do we have ((phi cons)|(x + (phi cons)) + con|(phi cons)) ? + // Push constant up through the phi: x + (phi con0+con0 con1+con1...) + static Node phiCon(Node op, boolean rotate) { + Node lhs = op.in(1); + Node rhs = op.in(2); + if( rhs._type==TypeInteger.TOP ) return null; + // LHS is either a Phi of constants, or another op with Phi of constants + PhiNode lphi = pcon(lhs,op); + if( rotate && lphi==null && lhs.nIns() > 2 ) { + // Only valid to rotate constants if both are same associative ops + if( lhs.getClass() != op.getClass() ) return null; + lphi = pcon(lhs.in(2),op); // Will rotate with the Phi push + } + if( lphi==null ) return null; + + // RHS is a constant or a Phi of constants + if( !(rhs instanceof ConstantNode) && pcon(rhs,op)==null ) + return null; + + // If both are Phis, must be same Region + if( rhs instanceof PhiNode && lphi.in(0) != rhs.in(0) ) + return null; + + // Note that this is the exact reverse of Phi pulling a common op down + // to reduce total op-count. We don't get in an endless push-up + // push-down peephole cycle because the constants all fold first. + Node[] ns = new Node[lphi.nIns()]; + ns[0] = lphi.in(0); + // Push constant up through the phi: x + (phi con0+con0 con1+con1...) + for( int i=1; i hi._nid; + } + + @Override Node copy(Node lhs, Node rhs) { return new AddNode(lhs,rhs); } + @Override Node copyF() { return new AddFNode(null,null); } + @Override public String err() { + if( !(in(1)._type instanceof TypeInteger) ) return "Cannot '"+label()+"' " + in(1)._type; + if( !(in(2)._type instanceof TypeInteger) ) return "Cannot '"+label()+"' " + in(2)._type; + return null; + } +} diff --git a/chapter17b/src/main/java/com/seaofnodes/simple/node/AndNode.java b/chapter17b/src/main/java/com/seaofnodes/simple/node/AndNode.java new file mode 100644 index 00000000..bd03d6cb --- /dev/null +++ b/chapter17b/src/main/java/com/seaofnodes/simple/node/AndNode.java @@ -0,0 +1,61 @@ +package com.seaofnodes.simple.node; + + +import com.seaofnodes.simple.type.Type; +import com.seaofnodes.simple.type.TypeInteger; + + +public class AndNode extends Node { + public AndNode(Node lhs, Node rhs) { super(null, lhs, rhs); } + + @Override public String label() { return "And"; } + + @Override protected String format() { return "(%1&%2)"; } + + @Override + public Type compute() { + Type t1 = in(1)._type, t2 = in(2)._type; + if( t1.isHigh() || t2.isHigh() ) + return TypeInteger.TOP; + if( t1 instanceof TypeInteger i0 && + t2 instanceof TypeInteger i1 ) { + if( i0.isConstant() && i1.isConstant() ) + return TypeInteger.constant(i0.value()&i1.value()); + // Sharpen allowed bits if either value is narrowed + long mask = i0.mask() & i1.mask(); + return mask < 0 ? TypeInteger.BOT : TypeInteger.make(0,mask); + } + return TypeInteger.BOT; + } + + @Override + public Node idealize() { + Node lhs = in(1); + Node rhs = in(2); + Type t1 = lhs._type; + Type t2 = rhs._type; + + // And of -1. We do not check for (-1&x) because this will already + // canonicalize to (x&-1) + if( t2.isConstant() && t2 instanceof TypeInteger i && i.value()==-1 ) + return lhs; + + // Move constants to RHS: con*arg becomes arg*con + if ( t1.isConstant() && !t2.isConstant() ) + return swap12(); + + // Do we have ((x & (phi cons)) & con) ? + // Do we have ((x & (phi cons)) & (phi cons)) ? + // Push constant up through the phi: x & (phi con0&con0 con1&con1...) + Node phicon = AddNode.phiCon(this,true); + if( phicon!=null ) return phicon; + + return null; + } + @Override Node copy(Node lhs, Node rhs) { return new AndNode(lhs,rhs); } + @Override String err() { + if( !(in(1)._type instanceof TypeInteger) ) return "Cannot '&' " + in(1)._type; + if( !(in(2)._type instanceof TypeInteger) ) return "Cannot '&' " + in(2)._type; + return null; + } +} diff --git a/chapter17b/src/main/java/com/seaofnodes/simple/node/BoolNode.java b/chapter17b/src/main/java/com/seaofnodes/simple/node/BoolNode.java new file mode 100644 index 00000000..6efde623 --- /dev/null +++ b/chapter17b/src/main/java/com/seaofnodes/simple/node/BoolNode.java @@ -0,0 +1,114 @@ +package com.seaofnodes.simple.node; + +import com.seaofnodes.print.ExprPrinter; + +import com.seaofnodes.simple.Parser; +import com.seaofnodes.simple.Utils; +import com.seaofnodes.simple.type.Type; +import com.seaofnodes.simple.type.TypeInteger; +import com.seaofnodes.simple.type.TypeFloat; +import com.seaofnodes.simple.type.TypeMemPtr; + +import static com.seaofnodes.simple.type.TypeInteger.*; + +abstract public class BoolNode extends Node { + + public BoolNode(Node lhs, Node rhs) { + super(null, lhs, rhs); + } + + abstract String op(); // String opcode name + + @Override + public String label() { return getClass().getSimpleName(); } + + @Override protected ExprPrinter _print1(ExprPrinter p) { + return p.open().n(in(1)).p(op()).n(in(2)).close(); + } + + @Override + public TypeInteger compute() { + Type t1 = in(1)._type; + Type t2 = in(2)._type; + if( t1.isHigh() || t2.isHigh() ) + return BOOL.dual(); + if( t1 instanceof TypeInteger i1 && + t2 instanceof TypeInteger i2 ) + return doOp(i1,i2); + if( t1 instanceof TypeFloat f1 && + t2 instanceof TypeFloat f2 && + f1.isConstant() && f2.isConstant() ) + return TypeInteger.constant(doOp(f1.value(), f2.value()) ? 1 : 0); + return BOOL; + } + + TypeInteger doOp(TypeInteger t1, TypeInteger t2) { throw Utils.TODO(); } + boolean doOp(double lhs, double rhs) { throw Utils.TODO(); } + + @Override + public Node idealize() { + // Compare of same + if( in(1)==in(2) ) + return new ConstantNode(doOp(ZERO,ZERO)); + + // Equals pushes constant to the right; 5==X becomes X==5. + if( this instanceof EQ ) { + if( !(in(2) instanceof ConstantNode) ) { + // con==noncon becomes noncon==con + if( in(1) instanceof ConstantNode || in(1)._nid > in(2)._nid ) + // Equals sorts by NID otherwise: non.high == non.low becomes non.low == non.high + return in(1)._type instanceof TypeFloat ? new EQF(in(2),in(1)) : new EQ(in(2),in(1)); + } + // Equals X==0 becomes a !X + if( (in(2)._type == ZERO || in(2)._type == TypeMemPtr.NULLPTR) ) + return new NotNode(in(1)); + } + + // Do we have ((phi cons) cmp con) ? + // Do we have ((phi cons) cmp (phi cons)) ? + // Push the compare up through the phi: (phi con0 cmp con, con1 cmp con...) + Node phicon = AddNode.phiCon(this,this instanceof EQ); + if( phicon!=null ) return phicon; + + return null; + } + + public static class EQ extends BoolNode { + public EQ(Node lhs, Node rhs) { super(lhs,rhs); } + String op() { return "=="; } + TypeInteger doOp(TypeInteger i1, TypeInteger i2) { + if( i1==i2 && i1.isConstant() ) return TRUE; + if( i1._max < i2._min || i1._min > i2._max ) return FALSE; + return BOOL; + } + Node copy(Node lhs, Node rhs) { return new EQ(lhs,rhs); } + Node copyF() { return new EQF(null,null); } + } + public static class LT extends BoolNode { + public LT(Node lhs, Node rhs) { super(lhs,rhs); } + String op() { return "<" ; } + TypeInteger doOp(TypeInteger i1, TypeInteger i2) { + if( i1._max < i2._min ) return TRUE; + if( i1._min >= i2._max ) return FALSE; + return BOOL; + } + Node copy(Node lhs, Node rhs) { return new LT(lhs,rhs); } + Node copyF() { return new LTF(null,null); } + } + public static class LE extends BoolNode { + public LE(Node lhs, Node rhs) { super(lhs,rhs); } + String op() { return "<="; } + TypeInteger doOp(TypeInteger i1, TypeInteger i2) { + if( i1._max <= i2._min ) return TRUE; + if( i1._min > i2._max ) return FALSE; + return BOOL; + } + Node copy(Node lhs, Node rhs) { return new LE(lhs,rhs); } + Node copyF() { return new LEF(null,null); } + } + + public static class EQF extends EQ { public EQF(Node lhs, Node rhs) { super(lhs,rhs); } boolean doOp(double lhs, double rhs) { return lhs == rhs; } } + public static class LTF extends LT { public LTF(Node lhs, Node rhs) { super(lhs,rhs); } boolean doOp(double lhs, double rhs) { return lhs < rhs; } } + public static class LEF extends LE { public LEF(Node lhs, Node rhs) { super(lhs,rhs); } boolean doOp(double lhs, double rhs) { return lhs <= rhs; } } + +} diff --git a/chapter17b/src/main/java/com/seaofnodes/simple/node/BulkMemPhiNode.java b/chapter17b/src/main/java/com/seaofnodes/simple/node/BulkMemPhiNode.java new file mode 100644 index 00000000..84f97189 --- /dev/null +++ b/chapter17b/src/main/java/com/seaofnodes/simple/node/BulkMemPhiNode.java @@ -0,0 +1,237 @@ +package com.seaofnodes.simple.node; + +import com.seaofnodes.simple.IterPeeps; +import com.seaofnodes.simple.type.Type; +import com.seaofnodes.simple.type.TypeMem; +import java.util.BitSet; + +/** + * A Phi for bulk memory. It covers all aliases except {@link #_aliases}; + * those aliases must be represented by parallel precise MemPhis at the same + * program slice. + */ +public class BulkMemPhiNode extends PhiNode { + + private static final BitSet EMPTY = new BitSet(); + + // Excluded Aliases; empty means NO exclusions. + // Each split clones the exclusions; published sets are never mutated. + public final BitSet _aliases; + + public BulkMemPhiNode(String label, Node... inputs) { + this(label,EMPTY,inputs); + } + + private BulkMemPhiNode(String label, BitSet aliases, Node... inputs) { + super(label,TypeMem.BOT,inputs); + _aliases = aliases; + } + + public boolean isSplit(int alias) { return _aliases.get(alias); } + + @Override public String label() { return "BulkPhi"+_aliases; } + + @Override + public Type compute() { + Type t = super.compute(); + return t instanceof TypeMem mem ? mem : + t==Type.BOTTOM ? TypeMem.BOT : + TypeMem.TOP; + } + + @Override + public Node idealize() { + Node progress = super.idealize(); + if( progress != null ) return progress; + if( ((RegionNode)region()).inProgress() || region().nIns()<=1 ) + return null; // Input is in-progress + + // "Peek through" a MemMerge that covers this alias set on its default + for( int i=1; i= mmm.nIns() || mmm.in(alias)==null) ) + return false; + return true; + } + + + // True if the MemMerge has no precise slice still covered by this Phi. + private boolean canPeek(MemMergeNode mmm) { + return mmm.in(1)!=null && missingAlias(mmm)==0; + } + + // Return an alias required by an input but still covered by this Phi, or 0. + private int inputAlias(Node n) { + return switch(n) { + case ProjNode proj -> 0; + case ConstantNode con -> 0; + case MemMergeNode mmm -> missingAlias(mmm); + case MemOpNode mem -> unsplit(mem._alias); + case BulkMemPhiNode bulk -> missingAlias(bulk); + default -> throw new AssertionError("Unexpected memory input "+n); + }; + } + + // Return an alias required by a user but still covered by this Phi, or 0. + private int outputAlias(Node use) { + // This decision depends backwards on an immediate user's alias/set. + // Normal graph-neighbor enqueueing flows from defs to uses, so retain + // an explicit forward dependency to revisit this Phi when the user + // sharpens. + use.addDepForwards(this); + return switch(use) { + case ScopeNode scope -> 0; + case MemMergeNode mmm -> missingAlias(mmm); + case BulkMemPhiNode bulk -> missingAlias(bulk); + case MemOpNode mem -> unsplit(mem._alias); + case MemPhiNode phi -> unsplit(phi._alias); + default -> { + assert use instanceof ReturnNode + : "Unexpected bulk-memory user "+use; + yield 0; + } + }; + } + + // Alias zero/one is bulk, and an already excluded precise alias cannot + // trigger another split of this Phi. + private int unsplit(int alias) { + if( alias <= 1 ) return 0; + assert !_aliases.get(alias); + return alias; + } + + // First alias excluded by the neighboring bulk Phi but not by this one. + private int missingAlias(BulkMemPhiNode bulk) { + for( int alias = bulk._aliases.nextSetBit(0); alias >= 0; alias = bulk._aliases.nextSetBit(alias+1) ) + if( !_aliases.get(alias) ) + return alias; + return 0; + } + + // Every explicit slot requests that alias, including a partial allocation + // input whose slot still points to this bulk Phi. + private int missingAlias(MemMergeNode mmm) { + for( int alias=2; alias= 0; old = _aliases.nextSetBit(old+1) ) + { assert old != alias; mmm.alias(old,precisePhi(old));} + mmm.alias(alias,precise); + assert checkMerge(mmm); + return mmm; + } + + // Find or make the precise Phi parallel to this bulk Phi at the same merge. + private Node precisePhi(int alias) { + MemPhiNode mphi = _findPhi(alias); + if( mphi!=null ) return mphi; + + mphi = new MemPhiNode("$"+alias,alias); + mphi.addDef(region()); + // Due to cycles, must set before calling peephole + mphi.setType(TypeMem.make(alias,Type.BOTTOM)); + for( int i=1; i= 0; alias = bulk._aliases.nextSetBit(alias+1) ) + if( alias >= mmm.nIns() || mmm.in(alias)==null ) + return false; + return true; + } + + @Override public boolean eq(Node n) { + return _aliases.equals(((BulkMemPhiNode)n)._aliases) && super.eq(n); + } + + @Override int hash() { return _aliases.hashCode(); } +} diff --git a/chapter17b/src/main/java/com/seaofnodes/simple/node/CFGNode.java b/chapter17b/src/main/java/com/seaofnodes/simple/node/CFGNode.java new file mode 100644 index 00000000..e85fc6ae --- /dev/null +++ b/chapter17b/src/main/java/com/seaofnodes/simple/node/CFGNode.java @@ -0,0 +1,136 @@ +package com.seaofnodes.simple.node; + +import com.seaofnodes.simple.Parser; +import com.seaofnodes.simple.type.*; +import com.seaofnodes.simple.Utils; + +import java.util.BitSet; +import java.util.HashSet; +import java.util.HashMap; + +/** Control Flow Graph Nodes + *

+ * CFG nodes have a immediate dominator depth (idepth) and a loop nesting + * depth(loop_depth). + *

+ * idepth is computed lazily upon first request, and is valid even in the + * Parser, and is used by peepholes during parsing and afterward. + *

+ * loop_depth is computed after optimization as part of scheduling. + * + */ +public abstract class CFGNode extends Node { + + public CFGNode(Node... nodes) { super(nodes); } + + public CFGNode cfg(int idx) { return (CFGNode)in(idx); } + + // Block head is Start, Region, CProj, but not e.g. If, Return, Stop + public boolean blockHead() { return false; } + + // ------------------------------------------------------------------------ + /** + * Immediate dominator tree depth, used to approximate a real IDOM during + * parsing where we do not have the whole program, and also peepholes + * change the CFG incrementally. + *

+ * See {@link ...} + */ + public char _idepth; + public int idepth() { return _idepth!=0 ? _idepth : cacheIDepth(idom().idepth()+1); } + // Zero depth means uncached. Check before narrowing so overflow cannot wrap. + final int cacheIDepth(int depth) { + assert 0 <= depth && depth <= Character.MAX_VALUE : "Dominator depth exceeds 65535"; + return _idepth = (char)depth; + } + + + // Return the immediate dominator of this Node and compute dom tree depth. + public CFGNode idom(Node dep) { return cfg(0); } + public final CFGNode idom() { return idom(null); } + + // Return the LCA of two idoms + public CFGNode domLCA(CFGNode rhs, Node dep) { + if( rhs==null ) return this; + CFGNode lhs = this; + while( lhs != rhs ) { + if( lhs==null || rhs==null ) return null; + int comp = lhs.idepth() - rhs.idepth(); + if( comp >= 0 ) lhs = (dep==null ? lhs : (CFGNode)lhs.addDep(dep)).idom(); + if( comp <= 0 ) rhs = (dep==null ? rhs : (CFGNode)rhs.addDep(dep)).idom(); + } + return lhs; + } + + // ------------------------------------------------------------------------ + // Loop nesting + public LoopNode loop() { return _ltree._head; } + public int loopDepth() { return _ltree==null ? 0 : _ltree.depth(); } + + LoopTree _ltree; + int _pre; // Pre-order numbers for loop tree finding + private static class LoopTree { + LoopTree _par; + final LoopNode _head; + int _depth; + LoopTree(LoopNode head) { _head = head; } + @Override public String toString() { return "LOOP"+_head._nid; } + int depth() { + return _depth==0 ? (_par==null ? 0 : (_depth = _par.depth()+1)) : _depth; + } + } + + // ------------------------------------------------------------------------ + // Tag all CFG Nodes with their containing LoopNode; LoopNodes themselves + // also refer to *their* containing LoopNode, as well as have their depth. + // Start is a LoopNode which contains all at depth 1. + public void buildLoopTree(StopNode stop) { + _ltree = stop._ltree = Parser.XCTRL._ltree = new LoopTree((StartNode)this); + _bltWalk(2,stop, new BitSet()); + } + private int _bltWalk(int pre, StopNode stop, BitSet post) { + // Pre-walked? + if( _pre!=0 ) return pre; + _pre = pre++; + // Pre-walk + for( Node use : _outputs ) + if( use instanceof CFGNode usecfg ) + pre = usecfg._bltWalk(pre,stop,post); + + // Post-order work: find innermost loop + LoopTree inner = null, ltree; + for( Node use : _outputs ) { + if( !(use instanceof CFGNode usecfg) ) continue; + // Child visited but not post-visited? + if( !post.get(usecfg._nid) ) { + // Must be a backedge to a LoopNode then + ltree = usecfg._ltree = new LoopTree((LoopNode)usecfg); + } else { + // Take child's loop choice, which must exist + ltree = usecfg._ltree; + // If falling into a loop, use the target loop's parent instead + if( ltree._head == usecfg ) { + if( ltree._par == null ) + // This loop never had an If test choose to take its + // exit, i.e. it is a no-exit infinite loop. + ltree._par = ltree._head.forceExit(stop)._ltree; + ltree = ltree._par; + } + } + // Sort inner loops. The decision point is some branch far removed + // from either loop head OR either backedge so requires pre-order + // numbers to figure out innermost. + if( inner == null ) { inner = ltree; continue; } + if( inner == ltree ) continue; // No change + LoopTree outer = ltree._head._pre > inner._head._pre ? inner : ltree; + inner = ltree._head._pre > inner._head._pre ? ltree : inner; + inner._par = outer; + } + // Set selected loop + if( inner!=null ) + _ltree = inner; + // Tag as post-walked + post.set(_nid); + return pre; + } +} diff --git a/chapter17b/src/main/java/com/seaofnodes/simple/node/CProjNode.java b/chapter17b/src/main/java/com/seaofnodes/simple/node/CProjNode.java new file mode 100644 index 00000000..53348b5a --- /dev/null +++ b/chapter17b/src/main/java/com/seaofnodes/simple/node/CProjNode.java @@ -0,0 +1,61 @@ +package com.seaofnodes.simple.node; + +import com.seaofnodes.print.ExprPrinter; + +import com.seaofnodes.simple.Parser; +import com.seaofnodes.simple.type.Type; +import com.seaofnodes.simple.type.TypeMem; +import com.seaofnodes.simple.type.TypeTuple; + +public class CProjNode extends CFGNode { + + // Which slice of the incoming multipart value + public final int _idx; + + // Debugging label + public final String _label; + + public CProjNode(Node ctrl, int idx, String label) { + super(ctrl); + _idx = idx; + _label = label; + } + + @Override public String label() { return _label; } + + @Override protected ExprPrinter _print1(ExprPrinter p) { return p.p(_label); } + + @Override public boolean isMultiTail() { return in(0).isMultiHead(); } + @Override public boolean blockHead() { return true; } + + public CFGNode ctrl() { return cfg(0); } + + @Override + public Type compute() { + Type t = ctrl()._type; + return t instanceof TypeTuple tt ? tt._types[_idx] : Type.BOTTOM; + } + + @Override + public Node idealize() { + if( ctrl()._type instanceof TypeTuple tt ) { + if( tt._types[_idx]==Type.XCONTROL ) + return Parser.XCTRL; // We are dead + if( ctrl() instanceof IfNode && tt._types[1-_idx]==Type.XCONTROL ) // Only true for IfNodes + return ctrl().in(0); // We become our input control + } + + // Flip a negating if-test, to remove the not + if( ctrl() instanceof IfNode iff && iff.pred().addDep(this) instanceof NotNode not ) + return new CProjNode(new IfNode(iff.ctrl(),not.in(1)).peephole(),1-_idx,_idx==0 ? "False" : "True"); + + return null; + } + + @Override + boolean eq( Node n ) { return _idx == ((CProjNode)n)._idx; } + + @Override + int hash() { return _idx; } + +} diff --git a/chapter17b/src/main/java/com/seaofnodes/simple/node/CastNode.java b/chapter17b/src/main/java/com/seaofnodes/simple/node/CastNode.java new file mode 100644 index 00000000..9ade5a50 --- /dev/null +++ b/chapter17b/src/main/java/com/seaofnodes/simple/node/CastNode.java @@ -0,0 +1,37 @@ +package com.seaofnodes.simple.node; + +import com.seaofnodes.print.ExprPrinter; + +import com.seaofnodes.simple.type.Type; +import com.seaofnodes.simple.type.TypeInteger; +import com.seaofnodes.simple.IterPeeps; + + +// Upcast (join) the input to a t. Used after guard test to lift an input. +// Can also be used to make a type-assertion if ctrl is null. +public class CastNode extends Node { + private final Type _t; + public CastNode(Type t, Node ctrl, Node in) { + super(ctrl, in); + _t = t; + setType(compute()); + } + + @Override public String label() { return "("+_t.str()+")"; } + + + + @Override protected ExprPrinter _print1(ExprPrinter p) { + return p.p(label()).n(in(1)); + } + + @Override + public Type compute() { + return in(1)._type.join(_t); + } + + @Override + public Node idealize() { + return in(1)._type.isa(_t) ? in(1) : null; + } +} diff --git a/chapter17b/src/main/java/com/seaofnodes/simple/node/ConstantNode.java b/chapter17b/src/main/java/com/seaofnodes/simple/node/ConstantNode.java new file mode 100644 index 00000000..426736ed --- /dev/null +++ b/chapter17b/src/main/java/com/seaofnodes/simple/node/ConstantNode.java @@ -0,0 +1,56 @@ +package com.seaofnodes.simple.node; + +import com.seaofnodes.print.ExprPrinter; + +import com.seaofnodes.simple.Parser; +import com.seaofnodes.simple.type.Type; + + +/** + * A Constant node represents a constant value. At present, the only constants + * that we allow are integer literals; therefore Constants contain an integer + * value. As we add other types of constants, we will refactor how we represent + * Constants. + *

+ * Constants have no semantic inputs. However, we set Start as an input to + * Constants to enable a forward graph walk. This edge carries no semantic + * meaning, and it is present solely to allow visitation. + *

+ * The Constant's value is the value stored in it. + */ +public class ConstantNode extends Node { + final Type _con; + public ConstantNode( Type type ) { + super(Parser.START); + _con = type; + } + + @Override protected String repeatName() { + return _con==null || _con.toString().length()<=32 ? null : uniqueName(); + } + + @Override + public String label() { return "Con"; } + + + @Override protected ExprPrinter _print1(ExprPrinter p) { + return p.p(_con); + } + + @Override public boolean isMultiTail() { return true; } + + @Override + public Type compute() { return _con; } + + @Override + public Node idealize() { return null; } + + @Override + boolean eq(Node n) { + ConstantNode con = (ConstantNode)n; // Contract + return _con==con._con; + } + + @Override + int hash() { return _con.hashCode(); } +} diff --git a/chapter17b/src/main/java/com/seaofnodes/simple/node/DivFNode.java b/chapter17b/src/main/java/com/seaofnodes/simple/node/DivFNode.java new file mode 100644 index 00000000..c678ac3e --- /dev/null +++ b/chapter17b/src/main/java/com/seaofnodes/simple/node/DivFNode.java @@ -0,0 +1,39 @@ +package com.seaofnodes.simple.node; + + +import com.seaofnodes.simple.type.Type; +import com.seaofnodes.simple.type.TypeFloat; + + +public class DivFNode extends Node { + public DivFNode(Node lhs, Node rhs) { super(null, lhs, rhs); } + + @Override public String label() { return "DivF"; } + + @Override protected String format() { return "(%1/%2)"; } + + @Override + public Type compute() { + if (in(1)._type instanceof TypeFloat i0 && + in(2)._type instanceof TypeFloat i1) { + if (i0.isConstant() && i1.isConstant()) + return TypeFloat.constant(i0.value()/i1.value()); + } + return in(1)._type.meet(in(2)._type); + } + + @Override + public Node idealize() { + Node lhs = in(1); + Node rhs = in(2); + Type t1 = lhs._type; + Type t2 = rhs._type; + + // Div of 1. + if ( t2.isConstant() && t2 instanceof TypeFloat i && i.value()==1 ) + return lhs; + + return null; + } + @Override Node copy(Node lhs, Node rhs) { return new DivFNode(lhs,rhs); } +} diff --git a/chapter17b/src/main/java/com/seaofnodes/simple/node/DivNode.java b/chapter17b/src/main/java/com/seaofnodes/simple/node/DivNode.java new file mode 100644 index 00000000..cd749a03 --- /dev/null +++ b/chapter17b/src/main/java/com/seaofnodes/simple/node/DivNode.java @@ -0,0 +1,40 @@ +package com.seaofnodes.simple.node; + + +import com.seaofnodes.simple.type.Type; +import com.seaofnodes.simple.type.TypeInteger; + + +public class DivNode extends Node { + public DivNode(Node lhs, Node rhs) { super(null, lhs, rhs); } + + @Override public String label() { return "Div"; } + + @Override protected String format() { return "(%1/%2)"; } + + @Override + public Type compute() { + Type t1 = in(1)._type, t2 = in(2)._type; + if( t1.isHigh() || t2.isHigh() ) + return TypeInteger.TOP; + if( t1 instanceof TypeInteger i1 && + t2 instanceof TypeInteger i2 ) { + if (i1.isConstant() && i2.isConstant()) + return i2.value() == 0 + ? TypeInteger.ZERO + : TypeInteger.constant(i1.value()/i2.value()); + } + return TypeInteger.BOT; + } + + @Override + public Node idealize() { + // Div of 1. + if( in(2)._type == TypeInteger.TRUE ) + return in(1); + return null; + } + + @Override Node copy(Node lhs, Node rhs) { return new DivNode(lhs,rhs); } + @Override Node copyF() { return new DivFNode(null,null); } +} diff --git a/chapter17b/src/main/java/com/seaofnodes/simple/node/IfNode.java b/chapter17b/src/main/java/com/seaofnodes/simple/node/IfNode.java new file mode 100644 index 00000000..2b53b3a3 --- /dev/null +++ b/chapter17b/src/main/java/com/seaofnodes/simple/node/IfNode.java @@ -0,0 +1,62 @@ +package com.seaofnodes.simple.node; + + +import com.seaofnodes.simple.IterPeeps; +import com.seaofnodes.simple.type.Type; +import com.seaofnodes.simple.type.TypeInteger; +import com.seaofnodes.simple.type.TypeTuple; +import java.util.HashSet; + +public class IfNode extends CFGNode implements MultiNode { + + public IfNode(Node ctrl, Node pred) { + super(ctrl, pred); + IterPeeps.add(this); // Because idoms are complex, just add it + } + + @Override + public String label() { return "If"; } + + @Override protected String format() { return "if( %1 )"; } + + @Override public boolean isMultiHead() { return true; } + + public Node ctrl() { return in(0); } + public Node pred() { return in(1); } + + @Override + public Type compute() { + // If the If node is not reachable then neither is any following Proj + if (ctrl()._type != Type.CONTROL && ctrl()._type != Type.BOTTOM ) + return TypeTuple.IF_NEITHER; + Node pred = pred(); + Type t = pred._type; + // High types mean NEITHER side is reachable. + // Wait until the type falls to decide which way to go. + if( t == Type.TOP || t == TypeInteger.TOP ) + return TypeTuple.IF_NEITHER; + // If constant is 0 then false branch is reachable + // Else true branch is reachable + if( t.isConstant() ) + return t.makeInit()==t ? TypeTuple.IF_FALSE : TypeTuple.IF_TRUE; + // Integers allow non-zero ranges: "1-65535" + if( t.makeZero().meet(t) != t ) + return TypeTuple.IF_TRUE; + + return TypeTuple.IF_BOTH; + } + + @Override + public Node idealize() { + // Hunt up the immediate dominator tree. If we find an identical if + // test on either the true or false branch, that side wins. + if( !pred()._type.isHighOrConst() ) + for( CFGNode dom = idom(), prior=this; dom!=null; prior = dom, dom = dom.idom() ) + if( dom.addDep(this) instanceof IfNode iff && iff.pred().addDep(this)==pred() && prior instanceof CProjNode prj ) { + setDef(1,new ConstantNode(TypeInteger.make(true,prj._idx==0?1:0)).peephole()); + return this; + } + return null; + } + +} diff --git a/chapter17b/src/main/java/com/seaofnodes/simple/node/LoadNode.java b/chapter17b/src/main/java/com/seaofnodes/simple/node/LoadNode.java new file mode 100644 index 00000000..85ad243b --- /dev/null +++ b/chapter17b/src/main/java/com/seaofnodes/simple/node/LoadNode.java @@ -0,0 +1,222 @@ +package com.seaofnodes.simple.node; + +import com.seaofnodes.print.ExprPrinter; + +import com.seaofnodes.simple.Utils; +import com.seaofnodes.simple.IterPeeps; +import com.seaofnodes.simple.type.*; +import java.util.BitSet; +import java.util.ArrayList; + +/** + * Load represents extracting a value from inside a memory object, + * in chapter 10 this means Struct fields. + */ +public class LoadNode extends MemOpNode { + + /** + * Load a value from a ptr.field. + * + * @param name The field we are loading + * @param mem The memory alias node - this is updated after a Store + * @param ptr The ptr to the struct base from where we load a field + * @param off The offset inside the struct base + */ + public LoadNode(String name, int alias, Type glb, Node mem, Node ptr, Node off) { + super(name, alias, glb, mem, ptr, off); + } + + @Override boolean canDrop(MemOpNode other, Node dep) { + return super.canDrop(other,dep) && !clobbered(dep); + } + + // Check only immediate memory users. Stores clobber memory; Phis and + // aggregates might lead to a clobber, so stop rather than search further. + private boolean clobbered(Node dep) { + Node mem = mem(); + mem.addDepForwards(dep); + for( Node use : mem._outputs ) { + if( use==null ) continue; + use.addDepForwards(dep); + if( use instanceof StoreNode || use instanceof PhiNode || + use instanceof MemMergeNode || + use instanceof NewNode ) return true; + } + return false; + } + + // Debugger label + @Override public String label() { return "ld_"+mlabel(); } + @Override + protected ExprPrinter _print1(ExprPrinter p) { return p.p(".").p(_name); } + + @Override + public Type compute() { + Type t = MemMergeNode.contents(mem(),_alias,this); + // Update declared forward ref to the actual. + if( _declaredType.isFRef() && t instanceof TypeMemPtr tmp && !tmp.isFRef() ) + _declaredType = tmp.withAccess(((TypeMemPtr)_declaredType)._ro); + Type rez = err()==null ? _declaredType.join(t) : _declaredType; + return ptr()._type.isFinal() || _declaredType.isFinal() ? rez.makeRO() : rez; + } + + @Override + public Node idealize() { + if( mem() instanceof MemMergeNode merge ) { + setDef(1,IterPeeps.add(merge.alias(_alias))); + return this; + } + Node ptr = ptr(); + + // Simple Load-after-Store on same address. + if( mem() instanceof StoreNode st && + _alias==st._alias && ptr == st.ptr() && off() == st.off() ) { // Must check same object + assert _name.equals(st._name); // Equiv class aliasing is perfect + return castRO(st.val()); + } + + // Simple Load-after-New on same address. + if( mem() instanceof ProjNode p && p.in(0) instanceof NewNode nnn && + ptr == nnn.proj(0) ) // Must check same object + return castRO(nnn.in(nnn.findAlias(_alias))); // Load from New init + + // Load-after-Store on same address, but bypassing provably unrelated + // stores. This is a more complex superset of the above two peeps. + // "Provably unrelated" is really weak. + if( ptr instanceof ReadOnlyNode ro ) + ptr = ro.in(1); + Node mem = mem(); + outer: + while( true ) { + mem.addDep(this); + switch( mem ) { + case MemMergeNode merge: + mem = merge.alias(_alias); + break; + case StoreNode st: + if( _alias==st._alias && ptr == st.ptr() && off() == st.off() ) + return castRO(st.val()); // Proved equal + // Can we prove unequal? Offsets do not overlap? + if( _alias==st._alias && !off()._type.join(st.off()._type).isHigh() && // Offsets overlap + !neverAlias(ptr,st.ptr()) ) // And might alias + break outer; // Cannot tell, stop trying + // Pointers cannot overlap + mem = st.mem(); // Proved never equal + break; + case PhiNode phi: break outer; // Assume related + case ConstantNode top: break outer; // Assume shortly dead + case ProjNode mproj: + if( mproj.in(0) instanceof NewNode nnn1 ) { + if( ptr instanceof ProjNode pproj && pproj.in(0) == mproj.in(0) ) + return castRO(nnn1.in(nnn1.findAlias(_alias))); // Load from New init + if( !(ptr instanceof ProjNode pproj && pproj.in(0) instanceof NewNode nnn2) ) + break outer; // Cannot tell, ptr not related to New + mem = nnn1.mem();// Bypass unrelated New + break; + } else break outer; + default: + break outer; + } + } + + // Push a Load up through a Phi, as long as it collapses on at least + // one arm. If at a Loop, the backedge MUST collapse - else we risk + // spinning the same transform around the loop indefinitely. + // BEFORE (2 Sts, 1 Ld): AFTER (1 St, 0 Ld): + // if( pred ) ptr.x = e0; val = pred ? e0 + // else ptr.x = e1; : e1; + // val = ptr.x; ptr.x = val; + if( mem() instanceof MemPhiNode memphi && memphi.region()._type == Type.CONTROL && memphi.nIns()== 3 && + // Offset can be hoisted + off() instanceof ConstantNode && + // Pointer can be hoisted + hoistPtr(ptr,memphi) ) { + + // Profit on RHS/Loop backedge + if( profit(memphi,2) || + // Else must not be a loop to count profit on LHS. + (!(memphi.region() instanceof LoopNode) && profit(memphi,1)) ) { + Node ld1 = ld(1); + Node ld2 = ld(2); + return new PhiNode(_name,_declaredType,memphi.region(),ld1,ld2); + } + } + + return null; + } + + private Node ld( int idx ) { + Node mem = mem(), ptr = ptr(); + LoadNode ld = new LoadNode(_name,_alias,_declaredType,mem.in(idx),ptr instanceof PhiNode && ptr.in(0)==mem.in(0) ? ptr.in(idx) : ptr,off()); + ld.setDef(0,in(0)); + return ld.peephole(); + } + + private static boolean neverAlias( Node ptr1, Node ptr2 ) { + return ptr1.in(0) != ptr2.in(0) && + // Unrelated allocations + ptr1 instanceof ProjNode && ptr1.in(0) instanceof NewNode && + ptr2 instanceof ProjNode && ptr2.in(0) instanceof NewNode; + } + + private static boolean hoistPtr(Node ptr, PhiNode memphi ) { + // Can I hoist ptr above the Region? + if( !(memphi.region() instanceof RegionNode r) ) + return false; // Dead or dying Region/Phi + // If ptr from same Region, then yes, just use hoisted split pointers + if( ptr instanceof PhiNode pphi && pphi.region() == r ) + return true; + + // No, so can we lift this ptr? + CFGNode cptr = ptr.cfg0(); + if( cptr != null ) + // Pointer is controlled high + // TODO: Really needs to be the LCA of all inputs is high + return cptr.idepth() <= r.idepth(); + + // Dunno without a longer walk + return false; + } + + // Profitable if we find a matching Store on this Phi arm. + private boolean profit(PhiNode phi, int idx) { + Node px = phi.in(idx); + if( px==null ) return false; + px.addDep(this); + if( px._type instanceof TypeMem mem && mem._t.isHighOrConst() ) return true; + if( px instanceof StoreNode st1 && _alias==st1._alias && ptr()==st1.ptr() && off()==st1.off() ) return true; + return false; + } + + // Read-Only is a deep property, and cannot be cast-away + private Node castRO(Node rez) { + if( (ptr()._type.isFinal() || _declaredType.isFinal()) && !rez._type.isFinal() ) + return new ReadOnlyNode(rez).peephole(); + return rez; + } + + // Memory writers which must follow this read. A packaging node is not a + // write, but can hide New's input, so follow this alias through aggregates. + public ArrayList antiDeps() { + ArrayList deps = new ArrayList<>(); + antiDeps(mem(),deps,new BitSet()); + return deps; + } + + private void antiDeps(Node mem, ArrayList deps, BitSet visit) { + if( visit.get(mem._nid) ) return; + visit.set(mem._nid); + for( Node use : mem._outputs ) { + if( use instanceof MemMergeNode merge ) { + Node slice = _alias 1; + while( nIns()<=alias ) addDef(null); + setDef(alias,mem); + } + + // Scalar contents of one alias. New's field inputs supply the initialized type; + // join it with the incoming contents for all previously allocated objects. + // Phis use their cached types, so this query does not recurse around loops. + static Type contents(Node mem, int alias, Node dep) { + mem.addDep(dep); + if( mem instanceof MemMergeNode merge ) + return contents(merge.alias(alias),alias,dep); + if( mem instanceof ProjNode proj && proj.in(0) instanceof NewNode nnn ) { + assert proj._idx==1 && nnn.field(alias)!=null; + nnn.addDep(dep); + Node init = nnn.in(nnn.findAlias(alias)).addDep(dep); + return contents(nnn.mem(),alias,dep).meet(init._type); + } + // There are no heap arguments in this chapter. Before the first New, + // the set of allocated objects (and hence stored values) is empty. + if( mem instanceof ProjNode proj && proj.in(0) instanceof StartNode ) return Type.TOP; + if( mem._type==Type.TOP || mem._type==TypeMem.TOP ) return Type.TOP; + if( mem._type instanceof TypeMem mt && mt._alias==alias ) return mt._t; + return Type.BOTTOM; + } + + @Override public String label() { return "MemMerge"; } + @Override public boolean isMem() { return true; } + @Override public Type compute() { return TypeMem.BOT; } + @Override protected ExprPrinter _print1(ExprPrinter p) { + p.p("MEM["); + for( int i=1; i=nIns() || in(i)==null) ) + alias(i,mem.in(i)); + IterPeeps.add(mem.in(1)); + setDef(1,mem.in(1)); + return this; + } + assert BulkMemPhiNode.checkMerge(this); + return progress ? this : null; + } +} diff --git a/chapter17b/src/main/java/com/seaofnodes/simple/node/MemOpNode.java b/chapter17b/src/main/java/com/seaofnodes/simple/node/MemOpNode.java new file mode 100644 index 00000000..0bf9b6ac --- /dev/null +++ b/chapter17b/src/main/java/com/seaofnodes/simple/node/MemOpNode.java @@ -0,0 +1,62 @@ +package com.seaofnodes.simple.node; + +import com.seaofnodes.simple.type.Type; +import com.seaofnodes.simple.type.TypeMemPtr; + +/** + * Convenience common base for Load and Store. + */ +public abstract class MemOpNode extends Node { + + public final String _name; + public final int _alias; + // Declared type; not final because it might be a forward-reference + // which will be lazily improved when the reference is declared. + public Type _declaredType; + + public MemOpNode(String name, int alias, Type glb, Node mem, Node ptr, Node off) { + super(null, mem, ptr, off); + _name = name; + _alias = alias; + _declaredType = glb; + } + public MemOpNode(String name, int alias, Type glb, Node mem, Node ptr, Node off, Node value) { + this(name, alias, glb, mem, ptr, off); + addDef(value); + } + + // + static String mlabel(String name) { return name.equals("[]") ? "ary" : (name.equals("#") ? "len" : name); } + String mlabel() { return mlabel(_name); } + + public Node mem() { return in(1); } + public Node ptr() { return in(2); } + public Node off() { return in(3); } + + // Extra conditions for factoring matching memory operations through a Phi. + // The caller has already checked the opcode, input shape and control. + boolean canDrop(MemOpNode other, Node dep) { + ptr().addDep(dep); + return _alias==other._alias && _declaredType==other._declaredType && err()==null; + } + + @Override + boolean eq(Node n) { + MemOpNode mem = (MemOpNode)n; // Invariant + return _alias==mem._alias; // When comparing types error to use "equals"; always use "==" + } + + @Override + int hash() { return _alias; } + + @Override + String err() { + Type ptr = ptr()._type; + // Already an error, but better error messages come from elsewhere + if( ptr == Type.BOTTOM ) return null; + // Better be a not-nil TMP + if( ptr instanceof TypeMemPtr tmp && !tmp._nil ) + return null; + return "Might be null accessing '" + _name + "'"; + } +} diff --git a/chapter17b/src/main/java/com/seaofnodes/simple/node/MemPhiNode.java b/chapter17b/src/main/java/com/seaofnodes/simple/node/MemPhiNode.java new file mode 100644 index 00000000..6aae00f9 --- /dev/null +++ b/chapter17b/src/main/java/com/seaofnodes/simple/node/MemPhiNode.java @@ -0,0 +1,42 @@ +package com.seaofnodes.simple.node; + +import com.seaofnodes.simple.IterPeeps; +import com.seaofnodes.simple.type.Type; +import com.seaofnodes.simple.type.TypeMem; + +/** A Phi for one field alias, parallel to a bulk Phi at the same Region. */ +public class MemPhiNode extends PhiNode { + public final int _alias; + + public MemPhiNode(String label, int alias, Node... inputs) { + super(label,TypeMem.make(alias,Type.BOTTOM),inputs); + assert alias > 1; + _alias = alias; + } + + @Override public String label() { return "MemPhi_"+_alias; } + + @Override public Type compute() { + assert BulkMemPhiNode.checkMem(this,_alias); + if( !(region() instanceof RegionNode r) ) + return region()._type==Type.XCONTROL ? TypeMem.TOP : _type; + if( r.inProgress() ) return _declaredType; + Type t = Type.TOP; + for( int i=1; i _print1(ExprPrinter p) { return p.p("Never"); } + + @Override public Type compute() { return TypeTuple.IF_BOTH; } + + @Override public Node idealize() { return null; } +} diff --git a/chapter17b/src/main/java/com/seaofnodes/simple/node/NewNode.java b/chapter17b/src/main/java/com/seaofnodes/simple/node/NewNode.java new file mode 100644 index 00000000..51341c41 --- /dev/null +++ b/chapter17b/src/main/java/com/seaofnodes/simple/node/NewNode.java @@ -0,0 +1,60 @@ +package com.seaofnodes.simple.node; + +import com.seaofnodes.print.ExprPrinter; + +import com.seaofnodes.simple.type.*; + +/** Allocate and initialize an object. Inputs {ctrl, $mem, size, fields...}; + * results {ptr, $mem}. + * The memory input and result cover only the aliases in the allocated struct. + */ +public class NewNode extends Node implements MultiNode { + + public final TypeMemPtr _ptr; + + public NewNode(TypeMemPtr ptr, Node... nodes) { + super(nodes); + _ptr = ptr; + assert nodes.length==3+ptr._obj._fields.length; + assert nodes[0]._type==Type.CONTROL || nodes[0]._type==Type.XCONTROL; + assert nodes[1]._type instanceof TypeMem; + assert nodes[2]._type instanceof TypeInteger; + for( int i=3; i _print1(ExprPrinter p) { + return p.p("new ").p(_ptr._obj.str()); + } + + // Find matching alias input + int findAlias(int alias) { + return 3+_ptr._obj.findAlias(alias); + } + + + @Override + public TypeTuple compute() { + return TypeTuple.make(_ptr,TypeMem.BOT); + } + + @Override + public Node idealize() { return null; } + + @Override + boolean eq(Node n) { return this == n; } + + @Override + int hash() { return _ptr.hashCode(); } +} diff --git a/chapter17b/src/main/java/com/seaofnodes/simple/node/Node.java b/chapter17b/src/main/java/com/seaofnodes/simple/node/Node.java new file mode 100644 index 00000000..e70fe495 --- /dev/null +++ b/chapter17b/src/main/java/com/seaofnodes/simple/node/Node.java @@ -0,0 +1,610 @@ +package com.seaofnodes.simple.node; + +import com.seaofnodes.print.BaseNode; + +import com.seaofnodes.simple.Parser; + +import com.seaofnodes.simple.Ary; +import com.seaofnodes.simple.IRPrinter; +import com.seaofnodes.simple.IterPeeps; +import com.seaofnodes.simple.Utils; +import com.seaofnodes.simple.type.Type; +import com.seaofnodes.simple.type.TypeFloat; +import java.util.*; +import java.util.function.Function; + +/** + * All Nodes in the Sea of Nodes IR inherit from the Node class. + * The Node class provides common functionality used by all subtypes. + * Subtypes of Node specialize by overriding methods. + */ +public abstract class Node extends BaseNode implements OutNode, Cloneable { + + /** + * Inputs to the node. These are use-def references to Nodes. + *

+ * Generally fixed length, ordered, nulls allowed, no unused trailing space. + * Ordering is required because e.g. "a/b" is different from "b/a". + * The first input (offset 0) is often a {@link CFGNode} node. + */ + public Ary _inputs; + + /** + * Outputs reference Nodes that are not null and have this Node as an + * input. These nodes are users of this node, thus these are def-use + * references to Nodes. + *

+ * Outputs directly match inputs, making a directed graph that can be + * walked in either direction. These outputs are typically used for + * efficient optimizations but otherwise have no semantics meaning. + */ + public Ary _outputs; + + /** + * Current computed type for this Node. This value changes as the graph + * changes and more knowledge is gained about the program. + */ + public Type _type; + + /** + * A private Global Static mutable counter, for unique node id generation. + * To make the compiler multithreaded, this field will have to move into a TLS. + * Starting with value 1, to avoid bugs confusing node ID 0 with uninitialized values. + * */ + private static int UNIQUE_ID = 1; + public static int UID() { return UNIQUE_ID; } + + protected Node(Node... inputs) { + super(UNIQUE_ID++); // allocate unique dense ID + _inputs = new Ary<>(Node.class); + Collections.addAll(_inputs,inputs); + _outputs = new Ary<>(Node.class); + for( Node n : _inputs ) + if( n != null ) + n.addUse( this ); + } + + // Easy reading label for debugger, e.g. "Add" or "Region" or "EQ" + public abstract String label(); + + public String p(int depth) { return IRPrinter.prettyPrint(this,depth); } + + public boolean isMultiHead() { return false; } + public boolean isMultiTail() { return false; } + + // ------------------------------------------------------------------------ + // Graph Node & Edge manipulation + + @Override public String typeName() { return _type==null ? null : _type.toString(); } + + /** + * Gets the ith input node + * @param i Offset of the input node + * @return Input node or null + */ + public Node in(int i) { return _inputs.get(i); } + public Node out(int i) { return _outputs.get(i); } + @Override public Ary outs() { return _outputs; } + + public int nIns() { return _inputs.size(); } + + public int nOuts() { return _outputs.size(); } + + public boolean isUnused() { return nOuts() == 0; } + + public CFGNode cfg0() { return (CFGNode)in(0); } + + /** + * Change a def into a Node. Keeps the edges correct, by removing + * the corresponding use->def edge. This may make the original + * def go dead. This function is co-recursive with {@link #kill}. + *

+ + * This method is the normal path for altering a Node, because it does the + * proper default edge maintenance. It also immediately kills + * Nodes that lose their last use; at times care must be taken to avoid + * killing Nodes that are being used without having an output Node. This + * definitely happens in the middle of recursive {@link #peephole} calls. + * + * @param idx which def to set + * @param new_def the new definition + * @return new_def for flow coding + */ + public N setDef(int idx, N new_def ) { + unlock(); + Node old_def = in(idx); + if( old_def == new_def ) return new_def; // No change + // If new def is not null, add the corresponding def->use edge + // This needs to happen before removing the old node's def->use edge as + // the new_def might get killed if the old node kills it recursively. + if( new_def != null ) + new_def.addUse(this); + // Set the new_def over the old (killed) edge + _inputs.set(idx,new_def); + if( old_def != null && // If the old def exists, remove a def->use edge + old_def.delUse(this) ) // If we removed the last use, the old def is now dead + old_def.kill(); // Kill old def + moveDepsToWorklist(); + // Return new_def for easy flow-coding + return new_def; + } + + // Remove the numbered input, compressing the inputs in-place. This + // shuffles the order deterministically - which is suitable for Region and + // Phi, but not for every Node. If the def goes dead, it is recursively + // killed, which may include 'this' Node. + Node delDef(int idx) { + unlock(); + Node old_def = in(idx); + _inputs.del(idx); + if( old_def.delUse(this) ) // If we removed the last use, the old def is now dead + old_def.kill(); // Kill old def + old_def.moveDepsToWorklist(); + return this; + } + + // Insert the numbered input, sliding other inputs to the right + Node insertDef(int idx, Node new_def) { + _inputs.add(idx,null); + return setDef(idx,new_def); + } + + /** + * Add a new def to an existing Node. Keep the edges correct by + * adding the corresponding def->use edge. + * + * @param new_def the new definition, appended to the end of existing definitions + * @return new_def for flow coding + */ + public Node addDef(Node new_def) { + unlock(); + // Add use->def edge + _inputs.add(new_def); + // If new def is not null, add the corresponding def->use edge + if( new_def != null ) + new_def.addUse(this); + return new_def; + } + + // Breaks the edge invariants, used temporarily + protected void addUse(N n) { _outputs.add(n); } + + // Remove node 'use' from 'def's (i.e. our) output list, by compressing the list in-place. + // Return true if the output list is empty afterward. + // Error is 'use' does not exist; ok for 'use' to be null. + protected boolean delUse( Node use ) { + _outputs.del(_outputs.find(use)); + moveDepsToWorklist(); // User-count and anti-dependence queries can now change. + return _outputs.isEmpty(); + } + + // Shortcut for "popping" until n nodes. A "pop" is basically a + // setDef(last,null) followed by lowering the nIns() count. + void popUntil(int n) { + unlock(); + while( nIns() > n ) { + Node old_def = _inputs.pop(); + if( old_def != null && // If it exists and + old_def.delUse(this) ) // If we removed the last use, the old def is now dead + old_def.kill(); // Kill old def + } + } + + /** + * Kill a Node with no uses, by setting all of its defs + * to null. This may recursively kill more Nodes, and is basically dead + * code elimination. + */ + public void kill( ) { + unlock(); + moveDepsToWorklist(); + assert isUnused(); // Has no uses, so it is dead + _type=null; // Flag as dead + while( nIns()>0 ) { // Set all inputs to null, recursively killing unused Nodes + Node old_def = _inputs.removeLast(); + if( old_def != null ) { + IterPeeps.add(old_def);// Revisit neighbor because removed use + if( old_def.delUse(this) ) // If we removed the last use, the old def is now dead + old_def.kill(); // Kill old def + } + } + assert isDead(); // Really dead now + } + + // Mostly used for asserts and printing. + public boolean isDead() { return isUnused() && nIns()==0 && _type==null; } + + // Shortcuts to stop DCE mid-parse + // Add bogus null use to keep node alive + public N keep() { addUse(null); return (N)this; } + // Remove bogus null. + public N unkeep() { delUse(null); return (N)this; } + // Test "keep" status + public boolean iskeep() { return _outputs.find(null) != -1; } + public void unkill() { + if( unkeep().isUnused() ) + kill(); + } + + // Replace self with nnn in the graph, making 'this' go dead + public void subsume( Node nnn ) { + assert nnn!=this; + while( nOuts() > 0 ) { + Node n = _outputs.removeLast(); + n.unlock(); + int idx = n._inputs.find(this); + n._inputs.set(idx,nnn); + n.moveDepsToWorklist(); // Rewiring can change a dependent query without changing type. + nnn.addUse(n); + IterPeeps.addAll(n._outputs); + } + kill(); + } + + // ------------------------------------------------------------------------ + // Graph-based optimizations + + /** + * Try to peephole at this node and return a better replacement Node. + * Always returns some not-null Node (often this). + */ + public final Node peephole() { + var obs = IterPeeps.midAssert() ? null : Parser.PARSER == null ? null : Parser.PARSER._obs; + if( obs != null ) obs.before(this); + Node n = peepholeOpt(); + Node rez = n == null ? this : deadCodeElim(n.peephole()); + if( obs != null ) obs.after(this, n == null ? null : rez, false); + return rez; + } + + /** + * Try to peephole at this node and return a better replacement Node if + * possible. We compute a {@link Type} and then check and replace: + *

    + *
  • if the Type {@link Type#isConstant}, we replace with a {@link ConstantNode}
    • + *
  • in a future chapter we will look for a + * Common Subexpression + * to eliminate.
    • + *
  • we ask the Node for a better replacement. The "better replacement" + * is things like {@code (1+2)} becomes {@code 3} and {@code (1+(x+2))} becomes + * {@code (x+(1+2))}. By canonicalizing expressions we fold common addressing + * math constants, remove algebraic identities and generally simplify the + * code.
    • + * + * Unlike peephole above, this explicitly returns null for no-change, or not-null + * for a better replacement (which can be this). + *
+ */ + public final Node peepholeOpt( ) { + ITER_CNT++; + // Compute initial or improved Type + Type old = setType(compute()); + + // Replace constant computations from non-constants with a constant node + if( !(this instanceof ConstantNode) && !(this instanceof XCtrlNode) && _type.isHighOrConst() ) + return (_type==Type.XCONTROL ? new XCtrlNode() : new ConstantNode(_type)).peepholeOpt(); + + // Global Value Numbering + if( _hash==0 ) { + Node n = GVN.get(this); // Will set _hash as a side effect + if( n==null ) + GVN.put(this,this); // Put in table now + else { + // Because of random worklist ordering, the two equal nodes + // might have different types. Because of monotonicity, both + // types are valid. To preserve monotonicity, the resulting + // shared Node has to have the best of both types. + n.setType(n._type.join(_type)); + _hash = 0; // Clear, since it never went in the table + return deadCodeElim(n);// Return previous; does Common Subexpression Elimination + } + } + + // Ask each node for a better replacement + Node n = idealize(); + if( n != null ) // Something changed + return n; // Report progress + + if( old==_type ) ITER_NOP_CNT++; + return old==_type ? null : this; // Report progress + } + public static int ITER_CNT, ITER_NOP_CNT; + + // m is the new Node, self is the old. + // Return 'm', which may have zero uses but is alive nonetheless. + // If self has zero uses (and is not 'm'), {@link #kill} self. + private Node deadCodeElim(Node m) { + // If self is going dead and not being returned here (Nodes returned + // from peephole commonly have no uses (yet)), then kill self. + if( m != this && isUnused() && !isDead() ) { + // Killing self - and since self recursively kills self's inputs we + // might end up killing 'm', which we are returning as a live Node. + // So we add a bogus extra null output edge to stop kill(). + m.keep(); // Keep m alive + kill(); // Kill self because replacing with 'm' + m.unkeep(); // Okay to peephole m + } + return m; + } + + /** + * This function needs to be + * Monotonic + * as it is part of a Monotone Analysis Framework. + * See for example this set of slides. + *

+ * For Chapter 2, all our Types are really integer constants, and so all + * the needed properties are trivially true, and we can ignore the high + * theory. Much later on, this will become important and allow us to do + * many fancy complex optimizations trivially... because theory. + *

+ * {@link #compute()} needs to be stand-alone, and cannot recursively call compute + * on its inputs, because programs are cyclic (have loops!) and this will just + * infinitely recurse until stack overflow. Instead, compute typically + * computes a new type from the {@link #_type} field of its inputs. + */ + public abstract Type compute(); + + // Set the type. Assert monotonic progress. + // If changing, add users to worklist. + public Type setType(Type type) { + Type old = _type; + assert old==null || type.isa(old); // Since _type not set, can just re-run this in assert in the debugger + if( old == type ) return old; + _type = type; // Set _type late for easier assert debugging + IterPeeps.addAll(_outputs); + moveDepsToWorklist(); + return old; + } + + /** + * This function rewrites the current Node into a more "idealized" form. + * This is the bulk of our peephole rewrite rules, and we use this to + * e.g. turn arbitrary collections of adds and multiplies with mixed + * constants into a normal form that's easy for hardware to implement. + * Example: An array addressing expression: + * 

   ary[idx+1]
+ * might turn into Sea-of-Nodes IR: + * 
   (ary+12)+((idx+1) * 4)
+ * This expression can then be idealized into: + * 
   ary + ((idx*4) + (12 + (1*4)))
+ * And more folding: + * 
   ary + ((idx<<2) + 16)
+ * And during code-gen: + * 
   MOV4 Rary,[Ridx<<2 +16] // or some such hardware-specific notation
+ *

+ * {@link #idealize} has a very specific calling convention: + *

    + *
  • If NO change is made, return {@code null} + *
  • If ANY change is made, return not-null; this can be {@code this} + *
  • The returned Node does NOT call {@link #peephole} on itself; the {@link #peephole} call will recursively peephole it. + *
  • Any NEW nodes that are not directly returned DO call {@link #peephole}. + *
+ *

+ * Examples: + * + * + * + * + * + *
before after return comment
{@code (x+5) }{@code (x+5) }{@code null }No change
{@code (5+x) }{@code (x+5) }{@code this }Swapped arguments
{@code ((x+1)+2)}{@code (x+(1+2))}{@code (x+_) }Returns 2 new Nodes
+ * + * The last entry deserves more discussion. The new Node {@code (1+2)} + * created in {@link #idealize} calls {@link #peephole} (which then folds + * into a constant). The other new Node {@code (x+3)} does not call + * peephole, because it is returned and peephole itself will recursively + * call peephole. + *

+ * Since idealize calls peephole and peephole calls idealize, you must be + * careful that all idealizations are monotonic: all transforms + * remove some feature, so that the set of available transforms always + * shrinks. If you don't, you risk an infinite peephole loop! + * + * @return Either a new or changed node, or null for no changes. + */ + public abstract Node idealize(); + + // Some of the peephole rules get complex, and search further afield than + // just the nearest neighbor. These peepholes can fail the pattern match + // on a node some distance away, and if that node ever changes we should + // retry the peephole. Track a set of Nodes dependent on `this`, and + // revisit them if `this` changes. + Ary _deps; + public int nDeps() { return _deps == null ? 0 : _deps.size(); } + public Node dep(int idx) { return _deps.get(idx); } + + /** + * Add a node to the list of dependencies. Only add it if its not an input + * or output of this node, that is, it is at least one step away. The node + * being added must benefit from this node being peepholed. + */ + Node addDep( Node dep ) { + return addDep(dep,false); + } + + // A bulk Phi inspects its users' partitions. Def-to-use propagation does + // not revisit that producer when an immediate user's partition changes. + Node addDepForwards(Node dep) { return addDep(dep,true); } + + private Node addDep(Node dep, boolean forwards) { + // Running peepholes during the big assert cannot have side effects + // like adding dependencies. + if( IterPeeps.midAssert() ) return this; + var obs = IterPeeps.midAssert() ? null : Parser.PARSER == null ? null : Parser.PARSER._obs; + if( obs != null ) obs.dep(this, dep); + if( _deps==null ) _deps = new Ary<>(Node.class); + if( _deps .find(dep) != -1 ) return this; // Already on list + if( !forwards && _inputs .find(dep) != -1 ) return this; // No need for deps on immediate neighbors + if( !forwards && _outputs.find(dep) != -1 ) return this; + _deps.add(dep); + return this; + } + + // Move the dependents onto a worklist, and clear for future dependents. + public void moveDepsToWorklist( ) { + if( _deps==null ) return; + IterPeeps.addAll(_deps); + _deps.clear(); + } + + // Global Value Numbering. Hash over opcode and inputs; hits in this table + // are structurally equal. + public static final HashMap GVN = new HashMap<>(); + + // Two nodes are equal if they have the same inputs and the same "opcode" + // which means the same Java class, plus same internal parts. + @Override public final boolean equals( Object o ) { + if( o==this ) return true; + if( o.getClass() != getClass() ) return false; + Node n = (Node)o; + int len = _inputs.size(); + if( len != n._inputs.size() ) return false; + for( int i=0; i>13) ^ n._nid; + if( hash==0 ) hash = 0xDEADBEEF; // Bad hash, so use some junky thing + return (_hash=hash); + } + // Subclasses add extra hash info (such as ConstantNodes constant) + int hash() { return 0; } + + // ------------------------------------------------------------------------ + // + + /** Is this Node Memory related */ + public boolean isMem() { return false; } + + // Semantic change to the graph (so NOT a peephole), used by the Parser. + // If any input is a float, flip to a float-flavored opcode and widen any + // non-float input. + public final Node widen() { + if( !hasFloatInput() ) return this; + Node flt = copyF(); + if( flt==null ) return this; + for( int i=1; i(Node.class); + n._outputs = new Ary<>(Node.class); + n._deps = null; + n._hash = 0; + return n; + } + + // Report any post-optimize errors + String err() { return null; } + + /** + * Used to allow repeating tests in the same JVM. This just resets the + * Node unique id generator, and is done as part of making a new Parser. + */ + public static void reset() { + UNIQUE_ID = 1; + GVN.clear(); + ITER_CNT = ITER_NOP_CNT = 0; + } + + // Utility to walk the entire graph applying a function; return the first + // not-null result. + private static final BitSet WVISIT = new BitSet(); + final public E walk( Function pred ) { + assert WVISIT.isEmpty(); + try { return _walk(pred); } + finally { WVISIT.clear(); } + } + + private E _walk( Function pred ) { + if( WVISIT.get(_nid) ) return null; // Been there, done that + WVISIT.set(_nid); + E x = pred.apply(this); + if( x != null ) return x; + for( Node def : _inputs ) if( def != null && (x = def._walk(pred)) != null ) return x; + for( Node use : _outputs ) if( use != null && (x = use._walk(pred)) != null ) return x; + return null; + } + + /** + * Debugging utility to find a Node by index + */ + public Node find(int nid) { + return walk( n -> n._nid==nid ? n : null ); + } +} diff --git a/chapter17b/src/main/java/com/seaofnodes/simple/node/NotNode.java b/chapter17b/src/main/java/com/seaofnodes/simple/node/NotNode.java new file mode 100644 index 00000000..b9cf4904 --- /dev/null +++ b/chapter17b/src/main/java/com/seaofnodes/simple/node/NotNode.java @@ -0,0 +1,39 @@ +package com.seaofnodes.simple.node; + + +import com.seaofnodes.simple.Utils; +import com.seaofnodes.simple.type.*; + +public class NotNode extends Node { + public NotNode(Node in) { super(null, in); } + + @Override public String label() { return "Not"; } + + @Override protected String format() { return "(!%1)"; } + + @Override + public Type compute() { + Type t0 = in(1)._type; + if( t0.isHigh() ) return TypeInteger.BOOL.dual(); + switch( t0 ) { + case TypeInteger i0: return i0._max < 0 || i0._min > 0 ? TypeInteger.FALSE : (i0==TypeInteger.ZERO ? TypeInteger.TRUE : TypeInteger.BOOL); + case TypeFloat i0: + return i0.isConstant() ? TypeInteger.constant(i0.value()==0 ? 1 : 0) : TypeInteger.BOOL; + case TypeMemPtr p0: + // top->top, bot->bot, null->1, *void->0, not-null ptr->0, ptr/nil->bot + // If input in null then true + // If input is not null ptr then false + if( p0 == TypeMemPtr.NULLPTR ) return TypeInteger.TRUE; + if( !p0._nil ) return TypeInteger.FALSE; + return TypeInteger.BOOL; + case Type t: + if( t0.getClass() != Type.class ) + // Only doing NOT on ints and ptrs + throw Utils.TODO(); + return TypeInteger.BOOL; + } + } + + @Override + public Node idealize() { return null; } +} diff --git a/chapter17b/src/main/java/com/seaofnodes/simple/node/OrNode.java b/chapter17b/src/main/java/com/seaofnodes/simple/node/OrNode.java new file mode 100644 index 00000000..5be31b88 --- /dev/null +++ b/chapter17b/src/main/java/com/seaofnodes/simple/node/OrNode.java @@ -0,0 +1,58 @@ +package com.seaofnodes.simple.node; + + +import com.seaofnodes.simple.type.Type; +import com.seaofnodes.simple.type.TypeInteger; + + +public class OrNode extends Node { + public OrNode(Node lhs, Node rhs) { super(null, lhs, rhs); } + + @Override public String label() { return "Or"; } + + @Override protected String format() { return "(%1|%2)"; } + + @Override + public Type compute() { + Type t1 = in(1)._type, t2 = in(2)._type; + if( t1.isHigh() || t2.isHigh() ) + return TypeInteger.TOP; + if( t1 instanceof TypeInteger i0 && + t2 instanceof TypeInteger i1 ) { + if( i0.isConstant() && i1.isConstant() ) + return TypeInteger.constant(i0.value()|i1.value()); + } + return TypeInteger.BOT; + } + + @Override + public Node idealize() { + Node lhs = in(1); + Node rhs = in(2); + Type t1 = lhs._type; + Type t2 = rhs._type; + + // Or of 0. We do not check for (0|x) because this will already + // canonicalize to (x|0) + if( t2.isConstant() && t2 instanceof TypeInteger i && i.value()==0 ) + return lhs; + + // Move constants to RHS: con*arg becomes arg*con + if ( t1.isConstant() && !t2.isConstant() ) + return swap12(); + + // Do we have ((x | (phi cons)) | con) ? + // Do we have ((x | (phi cons)) | (phi cons)) ? + // Push constant up through the phi: x | (phi con0|con0 con1|con1...) + Node phicon = AddNode.phiCon(this,true); + if( phicon!=null ) return phicon; + + return null; + } + @Override Node copy(Node lhs, Node rhs) { return new OrNode(lhs,rhs); } + @Override String err() { + if( !(in(1)._type instanceof TypeInteger) ) return "Cannot '|' " + in(1)._type; + if( !(in(2)._type instanceof TypeInteger) ) return "Cannot '|' " + in(2)._type; + return null; + } +} diff --git a/chapter17b/src/main/java/com/seaofnodes/simple/node/OutNode.java b/chapter17b/src/main/java/com/seaofnodes/simple/node/OutNode.java new file mode 100644 index 00000000..dbac136b --- /dev/null +++ b/chapter17b/src/main/java/com/seaofnodes/simple/node/OutNode.java @@ -0,0 +1,7 @@ +package com.seaofnodes.simple.node; + +import com.seaofnodes.simple.Ary; + +public interface OutNode { + Ary outs(); +} diff --git a/chapter17b/src/main/java/com/seaofnodes/simple/node/PhiNode.java b/chapter17b/src/main/java/com/seaofnodes/simple/node/PhiNode.java new file mode 100644 index 00000000..942748e7 --- /dev/null +++ b/chapter17b/src/main/java/com/seaofnodes/simple/node/PhiNode.java @@ -0,0 +1,201 @@ +package com.seaofnodes.simple.node; + +import com.seaofnodes.print.ExprPrinter; + +import com.seaofnodes.simple.type.Type; +import com.seaofnodes.simple.type.TypeMem; +import com.seaofnodes.simple.Utils; + + +public class PhiNode extends Node { + + final String _label; + + // The Phi type we compute must stay within the domain of the Phi. + // Example Int stays Int, Ptr stays Ptr, Control stays Control, Mem stays Mem. + final Type _declaredType; + + public PhiNode(String label, Type declaredType, Node... inputs) { super(inputs); _label = label; assert declaredType!=null; _declaredType = declaredType; } + + public static PhiNode make(String label, Type type, Node... inputs) { + return type instanceof TypeMem ? new BulkMemPhiNode(label,inputs) : new PhiNode(label,type,inputs); + } + + @Override public String label() { return "Phi_"+MemOpNode.mlabel(_label); } + + @Override + protected ExprPrinter _print1(ExprPrinter p) { + if( !(region() instanceof RegionNode r) || r.inProgress() ) + p.p("Z"); + p.p("Phi("); + for( Node in : _inputs ) p.n(in).p(","); + return p.unchar(',').close(); + } + + public CFGNode region() { return (CFGNode)in(0); } + @Override public boolean isMultiTail() { return true; } + @Override public boolean isMem() { return _declaredType instanceof TypeMem; } + + @Override + public Type compute() { + if( !(region() instanceof RegionNode r) ) + return region()._type==Type.XCONTROL ? (_type instanceof TypeMem ? TypeMem.TOP : Type.TOP) : _type; + // During parsing Phis have to be computed type pessimistically. + if( r.inProgress() ) return _declaredType; + // Set type to local top of the starting type + Type t = _declaredType.lub(); + for (int i = 1; i < nIns(); i++) + // If the region's control input is live, add this as a dependency + // to the control because we can be peeped should it become dead. + if( r.in(i).addDep(this)._type != Type.XCONTROL ) + t = t.meet(in(i)._type); + return t; + } + + @Override + public Node idealize() { + if( !(region() instanceof RegionNode r ) ) + return in(1); // Input has collapse to e.g. starting control. + if( r.inProgress() || r.nIns()<=1 ) + return null; // Input is in-progress + + // If we have only a single unique input, become it. + Node live = singleUniqueInput(); + if (live != null) + return live; + + // Phi(op(a,b,...),op(c,d,...)) -> op(Phi(a,c),Phi(b,d),...). + Node down; + if( same_op() && (down=drop_same_op())!=null ) return down; + + // If merging Phi(N, cast(N)) - we are losing the cast JOIN effects, so just remove. + if( nIns()==3 ) { + if( in(1) instanceof CastNode cast && cast.in(1).addDep(this)==in(2) ) return in(2); + if( in(2) instanceof CastNode cast && cast.in(1).addDep(this)==in(1) ) return in(1); + } + // If merging a null-checked null and the checked value, just use the value. + // if( val ) ..; phi(Region,False=0/null,True=val); + // then replace with plain val. + if( nIns()==3 ) { + int nullx = -1; + if( in(1)._type == in(1)._type.makeInit() ) nullx = 1; + if( in(2)._type == in(2)._type.makeInit() ) nullx = 2; + if( nullx != -1 ) { + Node val = in(3-nullx); + if( r.idom(this).addDep(this) instanceof IfNode iff && iff.pred().addDep(this)==val ) { + // Must walk the idom on the null side to make sure we hit False. + CFGNode idom = (CFGNode)r.in(nullx); + while( idom.nIns() > 0 && idom.in(0) != iff ) idom = idom.idom(); + if( idom instanceof CProjNode proj && proj._idx==1 ) + return val; + } + } + } + + return null; + } + + private boolean same_op() { + Node op = in(1); + if( op instanceof CFGNode || op instanceof ConstantNode || op instanceof PhiNode || + op instanceof ProjNode || op instanceof NewNode || op instanceof ScopeNode || op instanceof MemMergeNode ) return false; + // A bulk Phi must split its aliases before factoring precise Stores. + if( this instanceof BulkMemPhiNode ) return false; + // Bulk splitting currently identifies parallel slices by Region/alias. + // Factoring can introduce another slice at a different memory point; + // wait until that Region's bulk partitioning has finished. + if( op instanceof MemOpNode ) + for( Node use : region()._outputs ) + if( use instanceof BulkMemPhiNode ) { + use.addDepForwards(this); + return false; + } + Node busy = null; + for( int i=1; i1 ) { + for( Node use : n._outputs ) + if( use!=null && use!=this ) use.addDepForwards(this); + if( n instanceof StoreNode || busy!=null ) return false; + busy=n; + } + for( int j=1; j _print1(ExprPrinter p) { return p.p(_label); } + + @Override public CFGNode cfg0() { return in(0).cfg0(); } + + @Override public boolean isMultiTail() { return in(0).isMultiHead(); } + @Override public boolean isMem() { return _type instanceof TypeMem; } + + @Override + public Type compute() { + Type t = in(0)._type; + return t instanceof TypeTuple tt ? tt._types[_idx] : Type.BOTTOM; + } + + @Override public Node idealize() { return null; } + + @Override + boolean eq( Node n ) { return _idx == ((ProjNode)n)._idx; } + + @Override + int hash() { return _idx; } +} diff --git a/chapter17b/src/main/java/com/seaofnodes/simple/node/ReadOnlyNode.java b/chapter17b/src/main/java/com/seaofnodes/simple/node/ReadOnlyNode.java new file mode 100644 index 00000000..fa4e0242 --- /dev/null +++ b/chapter17b/src/main/java/com/seaofnodes/simple/node/ReadOnlyNode.java @@ -0,0 +1,26 @@ +package com.seaofnodes.simple.node; + + +import com.seaofnodes.simple.type.Type; +import com.seaofnodes.simple.type.TypeMemPtr; + + +/** + * Cast a pointer to read-only + */ +public class ReadOnlyNode extends Node { + public ReadOnlyNode( Node n ) { super(null,n); } + @Override public String label() { return "ReadOnly"; } + + @Override protected String format() { return "(const)%1"; } + @Override public Type compute() { + Type t = in(1)._type; + return t instanceof TypeMemPtr tmp ? tmp.makeRO() : t; + } + + @Override public Node idealize() { + if( in(1)._type instanceof TypeMemPtr tmp && tmp.isFinal() ) + return in(1); + return null; + } +} diff --git a/chapter17b/src/main/java/com/seaofnodes/simple/node/RegionNode.java b/chapter17b/src/main/java/com/seaofnodes/simple/node/RegionNode.java new file mode 100644 index 00000000..27866139 --- /dev/null +++ b/chapter17b/src/main/java/com/seaofnodes/simple/node/RegionNode.java @@ -0,0 +1,119 @@ +package com.seaofnodes.simple.node; + +import com.seaofnodes.print.ExprPrinter; + +import com.seaofnodes.simple.IterPeeps; +import com.seaofnodes.simple.Parser; +import com.seaofnodes.simple.Utils; +import com.seaofnodes.simple.type.Type; +import java.util.ArrayList; +import java.util.Arrays; +import java.util.HashSet; + +public class RegionNode extends CFGNode { + + public RegionNode(Node... nodes) { super(nodes); } + + @Override + public String label() { return "Region"; } + + @Override protected ExprPrinter _print1(ExprPrinter p) { + return p.p(label()); + } + + @Override public boolean isMultiHead() { return true; } + @Override public boolean blockHead() { return true; } + + @Override + public Type compute() { + if( inProgress() ) return Type.CONTROL; + Type t = Type.XCONTROL; + for (int i = 1; i < nIns(); i++) + t = t.meet(in(i)._type); + return t; + } + + @Override + public Node idealize() { + if( inProgress() ) return null; + // Delete dead paths into a Region + int path = findDeadInput(); + if( path != 0 && + // Do not delete the entry path of a loop (ok to remove the back + // edge and make the loop a single-entry Region which folds away + // the Loop). Folding the entry path confused the loop structure, + // moving the backedge to the entry point. + !(this instanceof LoopNode loop && loop.entry()==in(path)) ) { + // Cannot use the obvious output iterator here, because a Phi + // deleting an input might recursively delete *itself*. This + // shuffles the output array, and we might miss iterating an + // unrelated Phi. So on rare occasions we repeat the loop to get + // all the Phis. + int nouts = 0; + while( nouts != nOuts() ) { + nouts = nOuts(); + for( int i=0; i1 && in(nIns()-1) == null; + } + + // Never equal if inProgress + @Override boolean eq( Node n ) { + return !inProgress(); + } +} diff --git a/chapter17b/src/main/java/com/seaofnodes/simple/node/ReturnNode.java b/chapter17b/src/main/java/com/seaofnodes/simple/node/ReturnNode.java new file mode 100644 index 00000000..6c773c42 --- /dev/null +++ b/chapter17b/src/main/java/com/seaofnodes/simple/node/ReturnNode.java @@ -0,0 +1,42 @@ +package com.seaofnodes.simple.node; + +import com.seaofnodes.print.ExprPrinter; + +import com.seaofnodes.simple.type.*; + + +/** Keeps all preceding memory effects and the return value alive: {ctrl, $mem, value}. */ +public class ReturnNode extends CFGNode { + + public ReturnNode(Node ctrl, Node data, ScopeNode scope) { + // A synthetic never-taken loop exit has no source scope. + super(ctrl, scope == null ? null : scope.mem(), data); + } + + public Node ctrl() { return in(0); } + public Node mem () { return in(1); } + public Node expr() { return in(2); } + + @Override + public String label() { return "Return"; } + + @Override + protected ExprPrinter _print1(ExprPrinter p) { + p.p("return "); + p.n(expr()); + return p.p(";"); + } + + @Override + public Type compute() { + // Return exposes the complete memory state. + return TypeTuple.make(ctrl()._type,TypeMem.BOT,expr()._type); + } + + @Override + public Node idealize() { + if( ctrl()._type==Type.XCONTROL ) + return ctrl(); + return null; + } +} diff --git a/chapter17b/src/main/java/com/seaofnodes/simple/node/RoundF32Node.java b/chapter17b/src/main/java/com/seaofnodes/simple/node/RoundF32Node.java new file mode 100644 index 00000000..78e7698c --- /dev/null +++ b/chapter17b/src/main/java/com/seaofnodes/simple/node/RoundF32Node.java @@ -0,0 +1,33 @@ +package com.seaofnodes.simple.node; + + +import com.seaofnodes.simple.type.Type; +import com.seaofnodes.simple.type.TypeFloat; + + +public class RoundF32Node extends Node { + public RoundF32Node(Node lhs) { super(null, lhs); } + + @Override public String label() { return "RoundF32"; } + + @Override protected String format() { return "((f32)%1)"; } + + @Override + public Type compute() { + if (in(1)._type instanceof TypeFloat i0 && i0.isConstant() ) + return TypeFloat.constant((float)i0.value()); + return in(1)._type; + } + + @Override + public Node idealize() { + Node lhs = in(1); + Type t1 = lhs._type; + + // RoundF32 of float + if( t1 instanceof TypeFloat tf && tf._sz==32 ) + return lhs; + + return null; + } +} diff --git a/chapter17b/src/main/java/com/seaofnodes/simple/node/SarNode.java b/chapter17b/src/main/java/com/seaofnodes/simple/node/SarNode.java new file mode 100644 index 00000000..44233b3d --- /dev/null +++ b/chapter17b/src/main/java/com/seaofnodes/simple/node/SarNode.java @@ -0,0 +1,54 @@ +package com.seaofnodes.simple.node; + + +import com.seaofnodes.simple.type.Type; +import com.seaofnodes.simple.type.TypeInteger; + + +public class SarNode extends Node { + public SarNode(Node lhs, Node rhs) { super(null, lhs, rhs); } + + @Override public String label() { return "Sar"; } + + @Override protected String format() { return "(%1>>%2)"; } + + @Override + public Type compute() { + Type t1 = in(1)._type, t2 = in(2)._type; + if( t1.isHigh() || t2.isHigh() ) + return TypeInteger.TOP; + if (t1 instanceof TypeInteger i0 && + t2 instanceof TypeInteger i1) { + if( i0 == TypeInteger.ZERO ) + return TypeInteger.ZERO; + if( i0.isConstant() && i1.isConstant() ) + return TypeInteger.constant(i0.value()>>i1.value()); + if( i1.isConstant() ) { + int log = (int)i1.value(); + return TypeInteger.make(-1L<<(63-log),(1L<<(63-log))-1); + } + } + return TypeInteger.BOT; + } + + @Override + public Node idealize() { + Node lhs = in(1); + Node rhs = in(2); + Type t2 = rhs._type; + + // Sar of 0. + if( t2.isConstant() && t2 instanceof TypeInteger i && (i.value()&63)==0 ) + return lhs; + + // TODO: x >> 3 >> (y ? 1 : 2) ==> x >> (y ? 4 : 5) + + return null; + } + @Override Node copy(Node lhs, Node rhs) { return new SarNode(lhs,rhs); } + @Override String err() { + if( !(in(1)._type instanceof TypeInteger) ) return "Cannot '>>' " + in(1)._type; + if( !(in(2)._type instanceof TypeInteger) ) return "Cannot '>>' " + in(2)._type; + return null; + } +} diff --git a/chapter17b/src/main/java/com/seaofnodes/simple/node/ScopeNode.java b/chapter17b/src/main/java/com/seaofnodes/simple/node/ScopeNode.java new file mode 100644 index 00000000..753abe90 --- /dev/null +++ b/chapter17b/src/main/java/com/seaofnodes/simple/node/ScopeNode.java @@ -0,0 +1,416 @@ +package com.seaofnodes.simple.node; + +import com.seaofnodes.print.ExprPrinter; + +import com.seaofnodes.simple.IterPeeps; +import com.seaofnodes.simple.Parser; +import com.seaofnodes.simple.Ary; +import com.seaofnodes.simple.type.*; +import java.util.*; + +/** + * The Scope node is purely a parser helper - it tracks names to nodes with a + * stack of variable records. + */ +public class ScopeNode extends Node { + + /** + * The control is a name that binds to the currently active control + * node in the graph + */ + public static final String CTRL = "$ctrl"; + public static final String ARG0 = "arg"; + public static final String MEM0 = "$mem"; + + /** The tracked fields are now complex enough to deserve a array-of-structs layout + */ + public static class Var { + public final int _idx; // index in containing scope + public final String _name; // Declared name + private Type _type; // Declared type + public final boolean _final; // Final field + public Var(int idx, String name, Type type, boolean xfinal) { + _idx = idx; + _name = name; + _type = type; + _final = xfinal; + } + public Type type() { + if( !_type.isFRef() ) return _type; + // Update self to no longer use the forward ref type + Type def = Parser.TYPES.get(((TypeMemPtr)_type)._obj._name); + return (_type=_type.meet(def)); + } + public Type lazyGLB() { + Type t = type(); + return t instanceof TypeMemPtr ? t : t.glb(); + } + @Override public String toString() { + return _type.toString()+(_final ? " ": " !")+_name; + } + } + + public Node in(Var v) { return in(v._idx); } + + @Override public Type compute() { return Type.BOTTOM; } + @Override public Node idealize() { return null; } + + // All active/live variables in all nested scopes, all run together + public final Ary _vars; + + // Size of each nested lexical scope + public final Ary _lexSize; + + // True if parsing inside of a constructor + public final Ary _inCons; + + // Extra guards; tested predicates and casted results + private final Ary _guards; + + // A new ScopeNode + public ScopeNode() { + _type = Type.BOTTOM; + _vars = new Ary<>(Var .class); + _lexSize= new Ary<>(Integer.class); + _inCons = new Ary<>(Boolean.class); + _guards = new Ary<>(Node .class); + } + + @Override public String label() { return "Scope"; } + + @Override + protected ExprPrinter _print1(ExprPrinter p) { + p.p("Scope[ "); + int j=1; + for( int i=0; i N ctrl(N n) { return setDef(0,n); } + + public void push() { push(false); } + public void push(boolean inCon) { + assert _lexSize._len==_inCons._len; + _lexSize.push(_vars.size()); + _inCons.push(inCon); + } + public void pop() { + assert _lexSize._len==_inCons._len; + int n = _lexSize.pop(); + _inCons.pop(); + popUntil(n); + _vars.setLen(n); + } + + // Allocation fields live in the scope immediately outside the constructor + // block. Nested blocks retain that permission; surrounding bindings do not. + public boolean canInit(Var v) { + for( int i=_inCons._len-1; i>0; i-- ) + if( _inCons.at(i) ) + return v._idx >= _lexSize.at(i-1) && v._idx < _lexSize.at(i); + return false; + } + + public boolean inCon() { return _inCons.last(); } + + // Find name in reverse, return an index into _vars or -1. Linear scan + // instead of hashtable, but probably doesn't matter until the scan + // typically hits many dozens of variables. + int find( String name ) { + for( int i=_vars.size()-1; i>=0; i-- ) + if( _vars.get(i)._name.equals(name) ) + return i; + return -1; + } + + /** + * Create a new variable name in the current scope + */ + public boolean define( String name, Type declaredType, boolean xfinal, Node init ) { + assert name.charAt(0)!='$' || _lexSize.size()==1; // Later scopes do not define memory + if( _lexSize._len > 1 ) + for( int i=_vars.size()-1; i>=_lexSize.last(); i-- ) + if( _vars.get(i)._name.equals(name) ) + return false; // Double define + _vars.add(new Var(nIns(),name,declaredType,xfinal)); + addDef(init); + return true; + } + + /** + * Lookup a name in all scopes starting from most deeply nested. + * + * @param name Name to be looked up + * @return null if not found, or the implementing Node + */ + public Var lookup( String name ) { + int idx = find(name); + // -1 is missed in all scopes, not found + return idx == -1 ? null : update(_vars.at(idx),null); + } + + /** + * If the name is present in any scope, then redefine else null + * + * @param name Name being redefined + * @param n The node to bind to the name + */ + public void update( String name, Node n ) { + int idx = find(name); + assert idx>=0; + update(_vars.at(idx),n); + } + + public Var update( ScopeNode.Var v, Node st ) { + Node old = in(v._idx); + if( old instanceof ScopeNode loop ) { + // Lazy Phi! + Node def = loop.in(v._idx); + old = def instanceof PhiNode phi && loop.ctrl()==phi.region() + // Loop already has a real Phi, use it + ? def + // Set real Phi in the loop head + // The phi takes its one input (no backedge yet) from a recursive + // lookup, which might have insert a Phi in every loop nest. + : loop.setDef(v._idx,PhiNode.make(v._name, v.lazyGLB(), loop.ctrl(), loop.in(loop.update(v,null)._idx),null).peephole()); + setDef(v._idx,old); + } + if( st!=null ) setDef(v._idx,st); // Set new value + return v; + } + + /** + * Duplicate a ScopeNode; including all levels, up to Nodes. So this is + * neither shallow (would dup the Scope but not the internal HashMap + * tables), nor deep (would dup the Scope, the HashMap tables, but then + * also the program Nodes). + *

+ * If the {@code loop} flag is set, the edges are filled in as the original + * Scope, as an indication of Lazy Phis at loop heads. The goal here is to + * not make Phis at loop heads for variables which are never touched in the + * loop body. + *

+ * The new Scope is a full-fledged Node with proper use<->def edges. + */ + public ScopeNode dup() { return dup(false); } + public ScopeNode dup(boolean loop) { + ScopeNode dup = new ScopeNode(); + // Our goals are: + // 1) duplicate the name bindings of the ScopeNode across all stack levels + // 2) Make the new ScopeNode a user of all the nodes bound + // 3) Ensure that the order of defs is the same to allow easy merging + dup._vars .addAll(_vars ); + dup._lexSize.addAll(_lexSize); + dup._inCons .addAll(_inCons ); + dup._guards .addAll(_guards ); + // The dup'd guards all need dup'd keepers, to keep proper accounting + // when later removing all guards + for( Node n : _guards ) + if( !(n instanceof CFGNode) ) + n.keep(); + dup.addDef(ctrl()); // Control input is just copied + + // Memory is one binding, with the same lazy loop Phi as scalar names. + for( int i=1; i 0 ) { + Node cast = _guards.at(--i); + if( cast instanceof CFGNode ) continue; // Marker between guard sets + Node xpred = _guards.at(--i); + if( xpred == pred ) + return cast; + } + return pred; + } + + // Kill guards also + @Override public void kill() { + for( Node n : _guards ) + if( !(n instanceof CFGNode) ) + n.unkill(); + _guards.clear(); + super.kill(); + } + + + private Node replace( Node old, Node cast ) { + assert old!=null && old!=cast; + for( int i=0; i (x << i) + (c << i) + if( lhs instanceof AddNode add && add.addDep(this).in(2)._type instanceof TypeInteger c && c.isConstant() && c!=TypeInteger.ZERO ) { + long sum = c.value() << shl.value(); + if( Integer.MIN_VALUE <= sum && sum <= Integer.MAX_VALUE ) + return new AddNode( new ShlNode(add.in(1),rhs).peephole(), Parser.con(sum) ); + } + } + + // TODO: x << 3 << (y ? 1 : 2) ==> x << (y ? 4 : 5) + + return null; + } + @Override Node copy(Node lhs, Node rhs) { return new ShlNode(lhs,rhs); } + @Override String err() { + if( !(in(1)._type instanceof TypeInteger) ) return "Cannot '<<' " + in(1)._type; + if( !(in(2)._type instanceof TypeInteger) ) return "Cannot '<<' " + in(2)._type; + return null; + } +} diff --git a/chapter17b/src/main/java/com/seaofnodes/simple/node/ShrNode.java b/chapter17b/src/main/java/com/seaofnodes/simple/node/ShrNode.java new file mode 100644 index 00000000..757fd69e --- /dev/null +++ b/chapter17b/src/main/java/com/seaofnodes/simple/node/ShrNode.java @@ -0,0 +1,50 @@ +package com.seaofnodes.simple.node; + + +import com.seaofnodes.simple.type.Type; +import com.seaofnodes.simple.type.TypeInteger; + + +public class ShrNode extends Node { + public ShrNode(Node lhs, Node rhs) { super(null, lhs, rhs); } + + @Override public String label() { return "Shr"; } + + @Override protected String format() { return "(%1>>>%2)"; } + + @Override + public Type compute() { + Type t1 = in(1)._type, t2 = in(2)._type; + if( t1.isHigh() || t2.isHigh() ) + return TypeInteger.TOP; + if (t1 instanceof TypeInteger i0 && + t2 instanceof TypeInteger i1 ) { + if( i0 == TypeInteger.ZERO ) + return TypeInteger.ZERO; + if( i0.isConstant() && i1.isConstant() ) + return TypeInteger.constant(i0.value()>>>i1.value()); + } + return TypeInteger.BOT; + } + + @Override + public Node idealize() { + Node lhs = in(1); + Node rhs = in(2); + Type t2 = rhs._type; + + // Shr of 0. + if( t2.isConstant() && t2 instanceof TypeInteger i && (i.value()&63)==0 ) + return lhs; + + // TODO: x >>> 3 >>> (y ? 1 : 2) ==> x >>> (y ? 4 : 5) + + return null; + } + @Override Node copy(Node lhs, Node rhs) { return new ShrNode(lhs,rhs); } + @Override String err() { + if( !(in(1)._type instanceof TypeInteger) ) return "Cannot '>>>' " + in(1)._type; + if( !(in(2)._type instanceof TypeInteger) ) return "Cannot '>>>' " + in(2)._type; + return null; + } +} diff --git a/chapter17b/src/main/java/com/seaofnodes/simple/node/StartNode.java b/chapter17b/src/main/java/com/seaofnodes/simple/node/StartNode.java new file mode 100644 index 00000000..cefa2d72 --- /dev/null +++ b/chapter17b/src/main/java/com/seaofnodes/simple/node/StartNode.java @@ -0,0 +1,36 @@ +package com.seaofnodes.simple.node; + +import com.seaofnodes.print.ExprPrinter; + +import com.seaofnodes.simple.type.*; +import java.util.HashSet; +import static com.seaofnodes.simple.Utils.TODO; + +/** Start supplies control, whole memory, and the argument, in that order. */ +public class StartNode extends LoopNode implements MultiNode { + + final Type _arg; + + public StartNode(Type arg) { super(null); _arg = arg; _type = compute(); } + + @Override public String label() { return "Start"; } + + @Override protected ExprPrinter _print1(ExprPrinter p) { + return p.p(label()); + } + + @Override public boolean isMultiHead() { return true; } + @Override public boolean blockHead() { return true; } + @Override public CFGNode cfg0() { return this; } + + @Override public TypeTuple compute() { + return TypeTuple.make(Type.CONTROL,TypeMem.BOT,_arg); + } + + @Override public Node idealize() { return null; } + + // No immediate dominator, and idepth==0 + @Override public int idepth() { return 0; } + @Override public CFGNode idom(Node dep) { return null; } + +} diff --git a/chapter17b/src/main/java/com/seaofnodes/simple/node/StopNode.java b/chapter17b/src/main/java/com/seaofnodes/simple/node/StopNode.java new file mode 100644 index 00000000..d0eb5750 --- /dev/null +++ b/chapter17b/src/main/java/com/seaofnodes/simple/node/StopNode.java @@ -0,0 +1,89 @@ +package com.seaofnodes.simple.node; + +import com.seaofnodes.print.ExprPrinter; + +import com.seaofnodes.simple.type.Type; +import com.seaofnodes.simple.Parser; +import com.seaofnodes.simple.IterPeeps; +import com.seaofnodes.simple.GlobalCodeMotion; + + +public class StopNode extends CFGNode { + + public final String _src; + + public StopNode(String src) { + super(); + _src = src; + } + + @Override + public String label() { + return "Stop"; + } + + @Override + protected ExprPrinter _print1(ExprPrinter p) { + if( ret()!=null ) return p.n(ret()); + p.p("Stop[ "); + for( Node ret : _inputs ) + p.n(ret).p(" "); + return p.p("]"); + } + + @Override public boolean blockHead() { return true; } + + // If a single Return, return it. + // Otherwise, null because ambiguous. + public ReturnNode ret() { + return nIns()==1 ? (ReturnNode)in(0) : null; + } + + @Override + public Type compute() { + return Type.BOTTOM; + } + + @Override + public Node idealize() { + int len = nIns(); + for( int i=0; i { + String msg = n.err(); + if( msg != null && obs != null ) obs.error(n, msg); + return msg; + }); + if( err != null ) throw new RuntimeException(err); + if( obs != null ) obs.phase("TypeCheck"); + return this; + } + StopNode GCM() { + Parser.START.buildLoopTree(this); + + GlobalCodeMotion.buildCFG(this); + return this; + } +} diff --git a/chapter17b/src/main/java/com/seaofnodes/simple/node/StoreNode.java b/chapter17b/src/main/java/com/seaofnodes/simple/node/StoreNode.java new file mode 100644 index 00000000..a5f04dd2 --- /dev/null +++ b/chapter17b/src/main/java/com/seaofnodes/simple/node/StoreNode.java @@ -0,0 +1,125 @@ +package com.seaofnodes.simple.node; + +import com.seaofnodes.print.ExprPrinter; + +import com.seaofnodes.simple.Utils; +import com.seaofnodes.simple.IterPeeps; +import com.seaofnodes.simple.type.*; + + +/** + * Store represents setting a value to a memory based object, in chapter 10 + * this means a field inside a struct. + */ +public class StoreNode extends MemOpNode { + + private final boolean _init; // Initializing writes are allowed to write null + + /** + * @param name The struct field we are assigning to + * @param mem The memory alias node - this is updated after a Store + * @param ptr The ptr to the struct base where we will store a value + * @param off The offset inside the struct base + * @param value Value to be stored + */ + public StoreNode(String name, int alias, Type glb, Node mem, Node ptr, Node off, Node value, boolean init) { + super(name, alias, glb, mem, ptr, off, value); + _init = init; + } + + // Debugger label + @Override boolean canDrop(MemOpNode other, Node dep) { + return super.canDrop(other,dep) && _init==((StoreNode)other)._init; + } + + @Override public String label() { return "st_"+mlabel(); } + @Override public boolean isMem() { return true; } + + public Node val() { return in(4); } + + @Override + protected ExprPrinter _print1(ExprPrinter p) { + return p.p(".").p(_name).p("=").p( val()).p(";"); + } + + @Override + public Type compute() { + Type val = val()._type; + if( _declaredType.isFRef() && val instanceof TypeMemPtr tmp && !tmp.isFRef() ) + _declaredType = tmp; + Type t = val.join(_declaredType).meet(MemMergeNode.contents(mem(),_alias,this)); + return TypeMem.make(_alias,t); + } + + @Override + public Node idealize() { + if( mem() instanceof MemMergeNode merge ) { + setDef(1,IterPeeps.add(merge.alias(_alias))); + return this; + } + + + // Simple store-after-store on same address. Should pick up the + // required init-store being stomped by a first user store. + if( mem() instanceof StoreNode st && + ptr()==st.ptr() && _alias==st._alias && // Must check same object + off()==st.off() && // And same offset + ptr()._type instanceof TypeMemPtr && // No bother if weird dead pointers + // Must have exactly one use of "this" or you get weird + // non-serializable memory effects in the worse case. + checkOnlyUse(st) ) { + assert _name.equals(st._name); // Equiv class aliasing is perfect + setDef(1,st.mem()); + return this; + } + + // Simple store-after-new on same address. Should pick up the + // an init-store being stomped by a first user store. + if( mem() instanceof ProjNode st && st .in(0) instanceof NewNode nnn && + ptr() instanceof ProjNode ptr && ptr.in(0) == nnn && + ptr()._type instanceof TypeMemPtr tmp && // No bother if weird dead pointers + // Cannot fold a store of a single element over the array body initializer value + !(tmp._obj.isAry() && tmp._obj._fields[1]._alias==_alias) && + // Very sad strong cutout: val has to be legal to hoist to a New + // input, which means it cannot depend on the New. Many many + // things are legal here but difficult to check without doing a + // full dominator check. Example failure: + // "struct C { C? c; }; C self = new C { c=self; }" + val()._type.isHighOrConst() && + // Must have exactly one use of "this" or you get weird + // non-serializable memory effects in the worse case. + checkOnlyUse(st) && + // Folding away a broken store + err()==null ) { + nnn.setDef(nnn.findAlias(_alias),val()); + // Must retype the NewNode + nnn ._type = nnn. compute(); + mem()._type = mem().compute(); + return st; + } + + return null; + } + + // Check that "mem" has no uses except "this" + private boolean checkOnlyUse(Node mem) { + if( mem.nOuts()==1 ) return true; + // Add deps on the other uses (can be e.g. ScopeNode mid-parse) so that + // when the other uses go away we can retry. + for( Node use : mem._outputs ) + if( use != this ) + use.addDep(this); + return false; + } + + @Override + String err() { + String err = super.err(); + if( err != null ) return err; + TypeMemPtr tmp = (TypeMemPtr)ptr()._type; + if( tmp._ro || tmp._obj.field(_name)._final ) + return "Cannot modify final field '"+_name+"'"; + Type t = val()._type; + return _init || t.isa(_declaredType) ? null : "Cannot store "+t+" into field "+_declaredType+" "+_name; + } +} diff --git a/chapter17b/src/main/java/com/seaofnodes/simple/node/StructNode.java b/chapter17b/src/main/java/com/seaofnodes/simple/node/StructNode.java new file mode 100644 index 00000000..429b49cc --- /dev/null +++ b/chapter17b/src/main/java/com/seaofnodes/simple/node/StructNode.java @@ -0,0 +1,45 @@ +package com.seaofnodes.simple.node; + +import com.seaofnodes.print.ExprPrinter; + +import com.seaofnodes.simple.type.*; + +/** + * Build a compound object + */ +public class StructNode extends Node { + + public TypeStruct _ts; + + @Override public String label() { return _ts==null ? "STRUCT?" : _ts.str(); } + + @Override + protected ExprPrinter _print1(ExprPrinter p) { + if( _ts==null ) return p.p("STRUCT?"); + p.p(_ts._name).p(" {"); + for( int i=0; i _print1(ExprPrinter p) { return p.p("Xctrl"); } + @Override public Type compute() { return Type.XCONTROL; } + @Override public Node idealize() { return null; } +} diff --git a/chapter17b/src/main/java/com/seaofnodes/simple/node/XorNode.java b/chapter17b/src/main/java/com/seaofnodes/simple/node/XorNode.java new file mode 100644 index 00000000..ef7273b8 --- /dev/null +++ b/chapter17b/src/main/java/com/seaofnodes/simple/node/XorNode.java @@ -0,0 +1,58 @@ +package com.seaofnodes.simple.node; + + +import com.seaofnodes.simple.type.Type; +import com.seaofnodes.simple.type.TypeInteger; + + +public class XorNode extends Node { + public XorNode(Node lhs, Node rhs) { super(null, lhs, rhs); } + + @Override public String label() { return "Xor"; } + + @Override protected String format() { return "(%1^%2)"; } + + @Override + public Type compute() { + Type t1 = in(1)._type, t2 = in(2)._type; + if( t1.isHigh() || t2.isHigh() ) + return TypeInteger.TOP; + if( t1 instanceof TypeInteger i0 && + t2 instanceof TypeInteger i1 ) { + if( i0.isConstant() && i1.isConstant() ) + return TypeInteger.constant(i0.value()^i1.value()); + } + return TypeInteger.BOT; + } + + @Override + public Node idealize() { + Node lhs = in(1); + Node rhs = in(2); + Type t1 = lhs._type; + Type t2 = rhs._type; + + // Xor of 0. We do not check for (0^x) because this will already + // canonicalize to (x^0) + if( t2.isConstant() && t2 instanceof TypeInteger i && i.value()==0 ) + return lhs; + + // Move constants to RHS: con*arg becomes arg*con + if ( t1.isConstant() && !t2.isConstant() ) + return swap12(); + + // Do we have ((x ^ (phi cons)) ^ con) ? + // Do we have ((x ^ (phi cons)) ^ (phi cons)) ? + // Push constant up through the phi: x ^ (phi con0^con0 con1^con1...) + Node phicon = AddNode.phiCon(this,true); + if( phicon!=null ) return phicon; + + return null; + } + @Override Node copy(Node lhs, Node rhs) { return new XorNode(lhs,rhs); } + @Override String err() { + if( !(in(1)._type instanceof TypeInteger) ) return "Cannot '^' " + in(1)._type; + if( !(in(2)._type instanceof TypeInteger) ) return "Cannot '^' " + in(2)._type; + return null; + } +} diff --git a/chapter17b/src/main/java/com/seaofnodes/simple/print/SimpleGraphAdapter.java b/chapter17b/src/main/java/com/seaofnodes/simple/print/SimpleGraphAdapter.java new file mode 100644 index 00000000..7ba58e6f --- /dev/null +++ b/chapter17b/src/main/java/com/seaofnodes/simple/print/SimpleGraphAdapter.java @@ -0,0 +1,42 @@ +package com.seaofnodes.simple.print; + +import com.seaofnodes.graph.GraphAdapter; +import com.seaofnodes.graph.GraphSnapshot.*; +import com.seaofnodes.simple.node.*; +import com.seaofnodes.simple.node.Node; +import com.seaofnodes.simple.type.TypeMem; + +/** Chapter 17's view of the IR; browser, transport and layout are shared. */ +public class SimpleGraphAdapter extends GraphAdapter { + + @Override protected String edgeName(Node n, int i) { + return n instanceof ScopeNode scope && i < scope._vars.size() + ? scope._vars.get(i)._name : null; + } + @Override protected int projectionIndex(Node n) { return n instanceof ProjNode p ? p._idx : n instanceof CProjNode p ? p._idx : -1; } + + @Override protected Kind kind(Node n) { + if( n instanceof StopNode ) return Kind.STOP; + if( n instanceof ScopeNode ) return Kind.SCOPE; + if( n instanceof StartNode ) return Kind.CTRL; + if( n instanceof LoopNode ) return Kind.LOOP; + if( n instanceof RegionNode ) return Kind.REGION; + if( n instanceof PhiNode ) return Kind.PHI; + return n instanceof CFGNode ? Kind.CTRL : isMem(n) ? Kind.MEM : Kind.DATA; + } + + @Override protected Role role(Node n, int i) { + if( n instanceof ScopeNode || n instanceof ConstantNode || n instanceof XCtrlNode ) return Role.ASSOC; + if( n instanceof PhiNode ) return i == 0 ? Role.ASSOC : isMem(n) ? Role.MEM : Role.DATA; + if( n instanceof ProjNode || n instanceof CProjNode ) + return n instanceof CFGNode ? Role.CTRL : isMem(n) ? Role.MEM : Role.DATA; + if( n instanceof RegionNode && i == 0 ) return Role.ASSOC; + if( i == 0 || n instanceof RegionNode || n instanceof StopNode ) return Role.CTRL; + if( i == 1 && (n instanceof MemOpNode || n instanceof ReturnNode || n instanceof NewNode) ) return Role.MEM; + Node def = n.in(i); + if( def != null && isMem(def) ) return Role.MEM; + return Role.DATA; + } + + private boolean isMem(Node n) { return n.isMem() || n._type instanceof TypeMem; } +} diff --git a/chapter17b/src/main/java/com/seaofnodes/simple/print/SimpleGraphObserver.java b/chapter17b/src/main/java/com/seaofnodes/simple/print/SimpleGraphObserver.java new file mode 100644 index 00000000..d774967b --- /dev/null +++ b/chapter17b/src/main/java/com/seaofnodes/simple/print/SimpleGraphObserver.java @@ -0,0 +1,45 @@ +package com.seaofnodes.simple.print; + +import com.seaofnodes.graph.GraphCapture; +import com.seaofnodes.graph.GraphViewer; +import com.seaofnodes.simple.Parser; +import com.seaofnodes.simple.node.Node; +import java.util.ArrayList; +import java.io.IOException; + +/** Chapter 17's compilation context; capture and event bookkeeping are shared. */ +public class SimpleGraphObserver extends GraphCapture { + private Parser _parser; + private Node _ret; + private String _phase; + public SimpleGraphObserver() { super(new SimpleGraphAdapter()); } + public static void main(String[] args) throws IOException { + GraphViewer.run(new SimpleGraphObserver()); + } + @Override protected void compile(String src) { + _parser = new Parser(src); + _parser._obs = this; + _phase = "Parse"; + _ret = _parser.parse(); + phase(_phase); + _phase = "Iter"; + com.seaofnodes.simple.IterPeeps.iterate(_parser.STOP); + phase(_phase); + _phase = "TypeCheck"; + _parser.STOP.typeCheck(); + } + @Override protected String phase() { return _phase; } + @Override protected int pos() { return "Parse".equals(_phase) ? _parser.pos() : -1; } + @Override protected void detach() { + if( _parser != null ) _parser._obs = null; + _parser = null; + _ret = null; + } + @Override protected Node scope() { return _parser._scope; } + @Override protected void roots(ArrayList roots) { + roots.add(Parser.START); + roots.add(_parser.STOP); + roots.addAll(_parser._xScopes); + roots.add(_ret); + } +} diff --git a/chapter17b/src/main/java/com/seaofnodes/simple/type/Field.java b/chapter17b/src/main/java/com/seaofnodes/simple/type/Field.java new file mode 100644 index 00000000..71c2fded --- /dev/null +++ b/chapter17b/src/main/java/com/seaofnodes/simple/type/Field.java @@ -0,0 +1,77 @@ +package com.seaofnodes.simple.type; + +import com.seaofnodes.simple.Utils; +import java.util.ArrayList; + +/** + * Represents a field in a struct. This is not a Type in the type system. + */ +public class Field extends Type { + + // The pair {fieldName,type} uniquely identifies a field. + + // Field name + public final String _fname; + // Type of the field + public final Type _type; + // Unique memory alias, not sensibly part of a "type" but very convenient here. + public final int _alias; + // Field must be written to exactly once, no more, no less + public final boolean _final; + + private Field(String fname, Type type, int alias, boolean xfinal ) { + super(TFLD); + _fname = fname; + _type = type; + _alias = alias; + _final = xfinal; + } + // Make with existing alias + public static Field make( String fname, Type type, int alias, boolean xfinal ) { + return new Field(fname,type,alias,xfinal).intern(); + } + public Field makeFrom( Type type ) { + return type == _type ? this : new Field(_fname,type,_alias,_final).intern(); + } + @Override public Field makeRO() { return isFinal() ? this : make(_fname,_type.makeRO(),_alias,true); } + @Override public boolean isFinal() { return _final && _type.isFinal(); } + + public static final Field TEST = make("test",TypeInteger.ZERO,-2,false); + public static void gather(ArrayList ts) { ts.add(TEST); } + + @Override Field xmeet( Type that ) { + Field fld = (Field)that; // Invariant + assert _fname.equals(fld._fname); + assert _alias==fld._alias; + return make(_fname,_type.meet(fld._type),_alias,_final | fld._final); + } + + @Override + public Field dual() { return make(_fname,_type.dual(),_alias,!_final); } + + @Override public Field glb() { + Type glb = _type.glb(); + return glb==_type ? this : make(_fname,glb,_alias,_final); + } + + @Override public Field lub() { + Type lub = _type.lub(); + return lub==_type ? this : make(_fname,lub,_alias,_final); + } + + // Override in subclasses + int hash() { return _fname.hashCode() ^ _type.hashCode() ^ _alias ^ (_final ? 1024 : 0); } + + boolean eq(Type t) { + Field f = (Field)t; + return _fname.equals(f._fname) && _type==f._type && _alias==f._alias && _final==f._final; + } + + + @Override + public StringBuilder print( StringBuilder sb ) { + return _type.print(sb.append(_final?"":"!").append(_fname).append(":").append(_alias).append(" : ")); + } + + @Override public String str() { return _fname; } +} diff --git a/chapter17b/src/main/java/com/seaofnodes/simple/type/Type.java b/chapter17b/src/main/java/com/seaofnodes/simple/type/Type.java new file mode 100644 index 00000000..60afb668 --- /dev/null +++ b/chapter17b/src/main/java/com/seaofnodes/simple/type/Type.java @@ -0,0 +1,222 @@ +package com.seaofnodes.simple.type; + +import com.seaofnodes.simple.Utils; + +import java.util.ArrayList; +import java.util.HashMap; + +/** + * These types are part of a Monotone Analysis Framework, + * @see see for example this set of slides. + *

+ * The types form a lattice; @see a symmetric complete bounded (ranked) lattice. + *

+ * This wild lattice theory will be needed later to allow us to easily beef up + * the analysis and optimization of the Simple compiler... but we don't need it + * now, just know that it is coming along in a later Chapter. + *

g + * One of the fun things here is that while the theory is deep and subtle, the + * actual implementation is darn near trivial and is generally really obvious + * what we're doing with it. Right now, it's just simple integer math to do + * simple constant folding e.g. 1+2 == 3 stuff. + */ + +public class Type { + static final HashMap INTERN = new HashMap<>(); + + // ---------------------------------------------------------- + // Simple types are implemented fully here. "Simple" means: the code and + // type hierarchy are simple, not that the Type is conceptually simple. + static final byte TBOT = 0; // Bottom (ALL) + static final byte TTOP = 1; // Top (ANY) + static final byte TCTRL = 2; // Ctrl flow bottom + static final byte TXCTRL = 3; // Ctrl flow top (mini-lattice: any-xctrl-ctrl-all) + static final byte TSIMPLE = 4; // End of the Simple Types + static final byte TINT = 5; // All Integers; see TypeInteger + static final byte TFLT = 6; // All Integers; see TypeInteger + static final byte TTUPLE = 7; // Tuples; finite collections of unrelated Types, kept in parallel + static final byte TMEM = 8; // All memory (alias 0) or A slice of memory - with specific alias + static final byte TMEMPTR = 9; // Memory pointer type + static final byte TSTRUCT =10; // Structs; tuples with named fields + static final byte TFLD =11; // Fields into struct + static final byte TARRAY =12; // Array + + public final byte _type; + + public boolean is_simple() { return _type < TSIMPLE; } + private static final String[] STRS = new String[]{"Bot","Top","Ctrl","~Ctrl"}; + protected Type(byte type) { _type = type; } + + public static final Type BOTTOM = new Type( TBOT ).intern(); // ALL + public static final Type TOP = new Type( TTOP ).intern(); // ANY + public static final Type CONTROL = new Type( TCTRL ).intern(); // Ctrl + public static final Type XCONTROL = new Type( TXCTRL ).intern(); // ~Ctrl + public static Type[] gather() { + ArrayList ts = new ArrayList<>(); + ts.add(BOTTOM); + ts.add(CONTROL); + Field.gather(ts); + TypeInteger.gather(ts); + TypeFloat.gather(ts); + TypeMem.gather(ts); + TypeMemPtr.gather(ts); + TypeStruct.gather(ts); + TypeTuple.gather(ts); + int sz = ts.size(); + for( int i = 0; i < sz; i++ ) + ts.add(ts.get(i).dual()); + return ts.toArray(new Type[ts.size()]); + } + + // Is high or on the lattice centerline. + public boolean isHigh () { return _type==TTOP || _type==TXCTRL; } + public boolean isHighOrConst() { return _type==TTOP || _type==TXCTRL; } + + // Strict constant values, things on the lattice centerline. + // Excludes both high and low values + public boolean isConstant() { return false; } + + /** + * Display Type name in a format that's good for IR printer + */ + public StringBuilder typeName( StringBuilder sb) { return print(sb); } + + + // ---------------------------------------------------------- + + // Notes on Type interning: At the moment it is not easy to reset the + // interned types because we hold static references to several types and + // these are scattered around. This means the INTERN cache will retain all + // types from every run of the Parser. For this to work correctly types + // must be rigorous about defining when they are the same. Also types need + // to be immutable once defined. The rationale for interning is + // *correctness* with cyclic type definitions. Simple structural recursive + // checks go exponential with merely sharing, but with cycles they will + // stack overflow and crash. Intering means we do not need to have sharing + // checks with every type compare, only during interning. + + // Factory method which interns "this" + public T intern() { + T nnn = (T)INTERN.get(this); + if( nnn==null ) + INTERN.put(nnn=(T)this,this); + return nnn; + } + + private int _hash; // Hash cache; not-zero when set. + @Override + public final int hashCode() { + if( _hash!=0 ) return _hash; + _hash = hash(); + if( _hash==0 ) _hash = 0xDEADBEEF; // Bad hash from subclass; use some junk thing + return _hash; + } + // Override in subclasses + int hash() { return _type; } + + @Override + public final boolean equals( Object o ) { + if( o==this ) return true; + if( !(o instanceof Type t)) return false; + if( _type != t._type ) return false; + return eq(t); + } + // Overridden in subclasses; subclass can assume "this!=t" and java classes are same + boolean eq(Type t) { return true; } + + + // ---------------------------------------------------------- + public final Type meet(Type t) { + // Shortcut for the self case + if( t == this ) return this; + // Same-type is always safe in the subclasses + if( _type==t._type ) return xmeet(t); + // Reverse; xmeet 2nd arg is never "is_simple" and never equal to "this". + if( is_simple() ) return this.xmeet(t ); + if( t.is_simple() ) return t .xmeet(this); + return Type.BOTTOM; // Mixing 2 unrelated types + } + + // Compute meet right now. Overridden in subclasses. + // Handle cases where 'this.is_simple()' and unequal to 't'. + // Subclassed xmeet calls can assert that '!t.is_simple()'. + Type xmeet(Type t) { + assert is_simple(); // Should be overridden in subclass + // ANY meet anything is thing; thing meet ALL is ALL + if( _type==TBOT || t._type==TTOP ) return this; + if( _type==TTOP || t._type==TBOT ) return t; + // 'this' is {TCTRL,TXCTRL} + if( !t.is_simple() ) return BOTTOM; + // 't' is {TCTRL,TXCTRL} + return _type==TCTRL || t._type==TCTRL ? CONTROL : XCONTROL; + } + + public Type dual() { + return switch( _type ) { + case TBOT -> TOP; + case TTOP -> BOTTOM; + case TCTRL -> XCONTROL; + case TXCTRL -> CONTROL; + default -> throw Utils.TODO(); // Should not reach here + }; + } + + // ---------------------------------------------------------- + // Our lattice is defined with a MEET and a DUAL. + // JOIN is dual of meet of both duals. + public final Type join(Type t) { + if( this==t ) return this; + return dual().meet(t.dual()).dual(); + } + + // True if this "isa" t; e.g. 17 isa TypeInteger.BOT + public boolean isa( Type t ) { return meet(t)==t; } + + /** Compute greatest lower bound in the lattice */ + public Type glb() { return _type==TCTRL ? CONTROL : BOTTOM; } + /** Compute least upper bound in the lattice */ + public Type lub() { return _type==TCTRL ? XCONTROL : TOP; } + + // Make an initial/default version of this type. Typically, 0 for integers + // and null for nullable pointers. + public Type makeInit() { return this; } + // Make a zero version of this type, 0 for integers and null for pointers. + public Type makeZero() { return null; } + // Make a non-zero version of this type, if possible. Integers attempt to + // exclude zero from their range and pointers become not-null. + public Type nonZero() { return glb(); } + + // Writable array slots are invariant in their element access permissions. + // Otherwise an alias could insert a readonly pointer into a writable slot. + public boolean accessISA(Type dst) { return true; } + + // Is forward-reference + public boolean isFRef() { return false; } + + // All reachable struct Fields are final + public boolean isFinal() { return true; } + + // Make all reachable struct Fields final + public Type makeRO() { return this; } + + // ---------------------------------------------------------- + + // Size in bits to hold an instance of this type. + // Sizes are expected to be between 1 and 64 bits. + // Size 0 means this either takes no space (such as a known-zero field) + // or isn't a scalar to be stored in memory. + public int log_size() { throw Utils.TODO(); } + + // ---------------------------------------------------------- + // Useful in the debugger, which calls toString everywhere. + // This is a more verbose dev-friendly print. + @Override + public final String toString() { + return print(new StringBuilder()).toString(); + } + + public StringBuilder print(StringBuilder sb) { return is_simple() ? sb.append(STRS[_type]) : sb;} + + // This is used by error messages, and is a shorted print. + public String str() { return STRS[_type]; } +} diff --git a/chapter17b/src/main/java/com/seaofnodes/simple/type/TypeFloat.java b/chapter17b/src/main/java/com/seaofnodes/simple/type/TypeFloat.java new file mode 100644 index 00000000..f85abbed --- /dev/null +++ b/chapter17b/src/main/java/com/seaofnodes/simple/type/TypeFloat.java @@ -0,0 +1,120 @@ +package com.seaofnodes.simple.type; + +import java.util.ArrayList; + +/** + * Float Type + */ +public class TypeFloat extends Type { + + public final static TypeFloat TOP = make((byte)-64, 0); + public final static TypeFloat T32 = make((byte)-32, 0); + public final static TypeFloat ZERO= make((byte) 0, 0); + public final static TypeFloat B32 = make((byte) 32, 0); + public final static TypeFloat BOT = make((byte) 64, 0); + + /** +/-64 for double; +/-32 for float, or 0 for constants */ + public final byte _sz; + + /** + * The constant value or 0 + */ + public final double _con; + + private TypeFloat(byte sz, double con) { + super(TFLT); + _sz = sz ; + _con = con; + } + private static TypeFloat make(byte sz, double con) { + return new TypeFloat(sz,con).intern(); + } + + public static TypeFloat constant(double con) { return make((byte)0, con); } + + public static void gather(ArrayList ts) { ts.add(ZERO); ts.add(BOT); ts.add(B32); ts.add(constant(3.141592653589793)); } + + // FIXME this display format is problematic + // In visualizer '#' gets prepended if its a constant + @Override + public StringBuilder print(StringBuilder sb) { + if( this==TOP ) return sb.append("FltTop"); + if( this==T32 ) return sb.append("F32Top"); + if( this==B32 ) return sb.append("F32Bot"); + if( this==BOT ) return sb.append("FltBot"); + return sb.append(_con); + } + + @Override public String str() { + if( this==TOP ) return "~flt"; + if( this==T32 ) return "~f32"; + if( this==B32 ) return "f32"; + if( this==BOT ) return "flt"; + return ""+_con+(isF32() ? "f" : ""); + } + + /** + * Display Type name in a format that's good for IR printer + */ + @Override + public StringBuilder typeName(StringBuilder sb) { + if( this==TOP ) return sb.append("FltTop"); + if( this==T32 ) return sb.append("F32Top"); + if( this==B32 ) return sb.append("F32Bot"); + if( this==BOT ) return sb.append("FltBot"); + return sb.append(isF32() ? "F32" : "Flt"); + } + + boolean isF32() { return ((float)_con)==_con; } + @Override public boolean isHigh() { return _sz< 0; } + @Override public boolean isHighOrConst() { return _sz<=0; } + @Override public boolean isConstant() { return _sz==0; } + + @Override public int log_size() { + int sz = _sz==0 ? (isF32() ? 32 : 64) : Math.abs(_sz); + return _sz==32 ? 2 : 3; + } + + public double value() { return _con; } + + @Override + public Type xmeet(Type other) { + // Invariant from caller: 'this' != 'other' and same class (TypeFloat) + TypeFloat i = (TypeFloat)other; // Contract + // Larger size in i1, smaller in i0 + TypeFloat i0 = _sz < i._sz ? this : i; + TypeFloat i1 = _sz < i._sz ? i : this; + + if( i1._sz== 64 ) return BOT; + if( i0._sz==-64 ) return i1; + if( i1._sz== 32 ) + return i0._sz==0 && !i0.isF32() ? BOT : B32; + if( i1._sz!= 0 ) return i1; + // i1 is a constant + if( i0._sz==-32 ) + return i1.isF32() ? i1 : BOT; + // Since both are constants, and are never equals (contract) unequals + // constants fall to bottom + return i0.isF32() && i1.isF32() ? B32 : BOT; + } + + @Override + public Type dual() { + if( _sz==0 ) return this; // Constants are a self-dual + return make((byte)-_sz,0); + } + + @Override public Type glb() { return BOT; } + @Override public Type lub() { return TOP; } + @Override public TypeFloat makeInit() { return ZERO; } + @Override public TypeFloat makeZero() { return ZERO; } + + @Override + int hash() { return (int)(Double.hashCode(_con) ^ _sz); } + @Override + public boolean eq( Type t ) { + TypeFloat i = (TypeFloat)t; // Contract + return _con==i._con && _sz==i._sz; + } + +} diff --git a/chapter17b/src/main/java/com/seaofnodes/simple/type/TypeInteger.java b/chapter17b/src/main/java/com/seaofnodes/simple/type/TypeInteger.java new file mode 100644 index 00000000..b2979d7b --- /dev/null +++ b/chapter17b/src/main/java/com/seaofnodes/simple/type/TypeInteger.java @@ -0,0 +1,133 @@ +package com.seaofnodes.simple.type; + +import com.seaofnodes.simple.Utils; +import java.util.ArrayList; + +/** + * Integer Type + */ +public class TypeInteger extends Type { + + public final static TypeInteger TOP = make(false, 0); + public final static TypeInteger BOT = make(false, 1); + public final static TypeInteger ZERO= make(0,0); + public final static TypeInteger U1 = make(0,1); + public final static TypeInteger BOOL= U1; + public final static TypeInteger FALSE=ZERO; + public final static TypeInteger TRUE= make(1,1); + public final static TypeInteger I8 = make(-128,127); + public final static TypeInteger I16 = make(-32768,32767); + public final static TypeInteger I32 = make(-1L<<31,(1L<<31)-1); + + public final static TypeInteger U8 = make(0,255); + public final static TypeInteger U16 = make(0,65535); + public final static TypeInteger U32 = make(0,(1L<<32)-1); + + /** + * Describes an integer *range* - everything from min to max; both min and + * max are inclusive. If min==max, this is a constant. + * + * If min <= max, this is a below center (towards bottom). + * If min > max, this is an above center (towards top). + */ + public final long _min, _max; + + private TypeInteger(long min, long max) { super(TINT); _min = min; _max = max; } + public static TypeInteger make(long lo, long hi) { return new TypeInteger(lo,hi).intern(); } + public static TypeInteger make(boolean is_con, long con) { + return make(is_con ? con : (con==0 ? Long.MAX_VALUE : Long.MIN_VALUE), + is_con ? con : (con==0 ? Long.MIN_VALUE : Long.MAX_VALUE)); + } + + public static TypeInteger constant(long con) { return make(true, con); } + + public static void gather(ArrayList ts) { ts.add(ZERO); ts.add(BOT); ts.add(U1); ts.add(U8); } + + // FIXME this display format is problematic + // In visualizer '#' gets prepended if its a constant + @Override + public StringBuilder print(StringBuilder sb) { return sb.append(str()); } + + @Override public String str() { + if( this==TOP ) return "~int"; + if( this==BOT ) return "int"; + if( this==BOOL) return ("bool"); + if( this==I8 ) return ("i8"); + if( this==I16 ) return ("i16"); + if( this==I32 ) return ("i32"); + if( this==U8 ) return ("u8"); + if( this==U16 ) return ("u16"); + if( this==U32 ) return ("u32"); + if( isConstant() ) return ""+_min; + return "["+_min+"-"+_max+"]"; + } + + /** + * Display Type name in a format that's good for IR printer + */ + @Override + public StringBuilder typeName(StringBuilder sb) { + if( this==TOP ) return sb.append("IntTop"); + if( this==BOT ) return sb.append("IntBot"); + return sb.append("Int"); + } + + @Override public boolean isHigh () { return _min > _max; } + @Override public boolean isHighOrConst() { return _min >= _max; } + @Override public boolean isConstant () { return _min == _max; } + + @Override public int log_size() { + if( this==I8 || this==U8 || this==BOOL ) return 0; // 1<<0 == 1 bytes + if( this==I16 || this==U16 ) return 1; // 1<<1 == 2 bytes + if( this==I32 || this==U32 ) return 2; // 1<<2 == 4 bytes + if( this==BOT ) return 3; // 1<<3 == 8 bytes + if( isHighOrConst() ) return 0; + throw Utils.TODO(); + } + + public long value() { assert isConstant(); return _min; } + + // AND-mask of forced zeros. e.g. unsigned types will return their mask; + // u8 will return 0xFF. But also a range of 16-18 (0x10-0x12) will return + // 0x13 - no value in the range {16,17,18} will allow bit 0x04 to be set. + public long mask() { + if( isHigh() ) return 0; + if( isConstant() ) return _min; + //if( _min<0 ) return -1L; + //if( _max==Long.MAX_VALUE ) return -1L; + // Those bit positions which differ min to max + long x = _min ^ _max; + // Highest '1' bit in the differ set. Since the range is from min to + // max, all values below here are possible. + long ff1 = Long.highestOneBit(x); + // Make a all-1's mask from ff1, and set over the same bits (either min + // or max is ok). + long mask = _min | (ff1-1) | ff1; + return mask; + } + + @Override + public Type xmeet(Type other) { + // Invariant from caller: 'this' != 'other' and same class (TypeInteger) + TypeInteger i = (TypeInteger)other; // Contract + return make(Math.min(_min,i._min), Math.max(_max,i._max)); + } + + @Override public TypeInteger dual() { return make(_max,_min); } + @Override public TypeInteger glb() { return BOT; } + @Override public TypeInteger lub() { return TOP; } + @Override public TypeInteger makeInit() { return ZERO; } + @Override public TypeInteger makeZero() { return ZERO; } + @Override public TypeInteger nonZero() { + if( isHigh() ) return this; + if( _min==0 ) return make(1,Math.max(_max,1)); // specifically good on BOOL + if( _max==0 ) return make(_min,-1); + return this; + } + @Override int hash() { return (int)((_min ^ (_min>>32)) *(_max ^ (_max>>32))); } + @Override + public boolean eq( Type t ) { + TypeInteger i = (TypeInteger)t; // Contract + return _min==i._min && _max==i._max; + } +} diff --git a/chapter17b/src/main/java/com/seaofnodes/simple/type/TypeMem.java b/chapter17b/src/main/java/com/seaofnodes/simple/type/TypeMem.java new file mode 100644 index 00000000..6dcd401a --- /dev/null +++ b/chapter17b/src/main/java/com/seaofnodes/simple/type/TypeMem.java @@ -0,0 +1,69 @@ +package com.seaofnodes.simple.type; + +import com.seaofnodes.simple.Utils; +import java.lang.Long; +import java.util.BitSet; +import java.util.ArrayList; + + +/** + * Represents a slice of memory corresponding to a set of aliases + */ +public class TypeMem extends Type { + + // Which slice of memory? + // 0 means TOP, no slice. + // -1 means BOT, all memory. + // N means slice#N. + public final int _alias; + public final Type _t; // Memory contents, some scalar type + + private TypeMem(int alias, Type t) { super(TMEM); _alias = alias; _t = t; } + + public static TypeMem make(int alias, Type t) { return new TypeMem(alias,t).intern(); } + public static final TypeMem TOP = make(-1, Type.TOP ); + public static final TypeMem BOT = make(-1, Type.BOTTOM); + + public static void gather(ArrayList ts) { ts.add(make(1,TypeInteger.ZERO)); ts.add(BOT); } + + @Override + TypeMem xmeet(Type t) { + TypeMem that = (TypeMem) t; // Invariant: TypeMem and unequal + if( this==TOP ) return that; + if( that==TOP ) return this; + if( this==BOT ) return BOT; + if( that==BOT ) return BOT; + int alias = _alias==that._alias ? _alias : -1; + Type mt = _t.meet(that._t); + return make(alias,mt); + } + + @Override + public Type dual() { + return make(_alias,_t.dual()); + } + + @Override public Type glb() { return make(_alias,_t.glb()); } + @Override public Type lub() { return make(_alias,_t.lub()); } + + @Override + int hash() { return 9876543 + _alias + _t.hashCode(); } + + @Override + boolean eq(Type t) { + TypeMem that = (TypeMem) t; // Invariant + return _alias == that._alias && _t == that._t; + } + + @Override + public StringBuilder print(StringBuilder sb) { + if( this==BOT ) return sb.append("MemBot"); + if( this==TOP ) return sb.append("MemTop"); + sb.append("MEM#"); + if( _alias== 0 ) return sb.append("TOP"); + if( _alias==-1 ) return sb.append("BOT"); + return _t.print(sb.append(_alias).append(":")); + } + + @Override public String str() { return toString(); } +} diff --git a/chapter17b/src/main/java/com/seaofnodes/simple/type/TypeMemPtr.java b/chapter17b/src/main/java/com/seaofnodes/simple/type/TypeMemPtr.java new file mode 100644 index 00000000..8ecc8031 --- /dev/null +++ b/chapter17b/src/main/java/com/seaofnodes/simple/type/TypeMemPtr.java @@ -0,0 +1,123 @@ +package com.seaofnodes.simple.type; + +import java.util.ArrayList; + +/** + * Represents a Pointer to memory. + * + * Null is generic pointer to non-existent memory. + * *void is a non-Null pointer to all possible refs, both structs and arrays. + * Pointers can be to specific struct and array types, or a union with Null. + * The distinguished *$BOT ptr represents union of *void and Null. + * The distinguished *$TOP ptr represents the dual of *$BOT. + */ +public class TypeMemPtr extends Type { + // A TypeMemPtr is pair (obj,nil) + // where obj is a TypeStruct, possibly TypeStruct.BOT + // where nil is an explicit null is allowed or not + + // Examples: + // (Person,false) - a not-nil Person + // (Person,true ) - a Person or a nil + // (BOT ,false) - a not-nil void* (unspecified struct) + // (TOP ,true ) - a nil + + public final TypeStruct _obj; + // Deep read-only access through this pointer; independent of slot finality. + public boolean _ro; + + public final boolean _nil; + + private TypeMemPtr(TypeStruct obj, boolean nil) { + super(TMEMPTR); + assert obj!=null; + _obj = obj; + _ro = obj==TypeStruct.BOT; + _nil = nil; + } + public static TypeMemPtr make(TypeStruct obj, boolean nil) { return new TypeMemPtr(obj, nil).intern(); } + public static TypeMemPtr make(TypeStruct obj) { return make(obj, false); } + public TypeMemPtr makeFrom(TypeStruct obj) { return obj==_obj ? this : make(obj, _nil).withAccess(_ro); } + public TypeMemPtr makeFrom(boolean nil) { return nil==_nil ? this : make(_obj, nil).withAccess(_ro); } + @Override public TypeMemPtr makeRO() { return withAccess(true); } + @Override public boolean isFinal() { return _ro; } + + public TypeMemPtr withAccess(boolean ro) { + if( _ro==ro || (_obj==TypeStruct.TOP && _nil) ) return this; + TypeMemPtr ptr = new TypeMemPtr(_obj, _nil); + ptr._ro = ro; + return ptr.intern(); + } + + // Writable slots can load and store references, so their element access + // must agree in both directions. A read-only outer view can weaken access. + @Override public boolean accessISA(Type dst) { + if( !(dst instanceof TypeMemPtr ptr) ) return true; + if( _ro && !ptr._ro ) return false; + if( ptr._ro || _obj._fields==null || ptr._obj._fields==null || !_obj.isAry() || !ptr._obj.isAry() ) return true; + Type a = _obj._fields[1]._type, b = ptr._obj._fields[1]._type; + return a.accessISA(b) && b.accessISA(a); + } + + // An abstract pointer, pointing to either a Struct or an Array. + // Can also be null or not. + public static final TypeMemPtr BOT = make(TypeStruct.BOT,true); + public static final TypeMemPtr TOP = BOT.dual(); + // An abstract null (can be Struct or Array) or not-null C void* + public static final TypeMemPtr NULLPTR = make(TypeStruct.TOP,true); + public static final TypeMemPtr VOIDPTR = NULLPTR.dual(); // A bottom mix of not-null ptrs, like C's void* but not null + + public static final TypeMemPtr TEST= make(TypeStruct.TEST,false); + public static void gather(ArrayList ts) { ts.add(NULLPTR); ts.add(BOT); ts.add(TEST); ts.add(TEST.makeRO()); } + + @Override + Type xmeet(Type t) { + TypeMemPtr that = (TypeMemPtr) t; + return TypeMemPtr.make((TypeStruct)_obj.meet(that._obj), _nil | that._nil).withAccess(_ro | that._ro); + } + + @Override + public TypeMemPtr dual() { return TypeMemPtr.make(_obj.dual(), !_nil).withAccess(!_ro); } + + @Override public TypeMemPtr glb() { return make(_obj.glb(),true ).withAccess(true); } + @Override public TypeMemPtr lub() { return make(_obj.lub(),false); } + // Is forward-reference + @Override public boolean isFRef() { return _obj.isFRef(); } + @Override public Type makeInit() { return _nil ? NULLPTR : Type.TOP; } + @Override public Type makeZero() { return NULLPTR; } + @Override public Type nonZero() { return VOIDPTR; } + + @Override public boolean isHigh() { return this==TOP; } + @Override public boolean isConstant() { return this==NULLPTR; } + @Override public boolean isHighOrConst() { return this==TOP || this==NULLPTR; } + + @Override public int log_size() { return 2; } // (1<<2)==4-byte pointers + + @Override + int hash() { return (_ro ? 8192 : 0) ^ _obj.hashCode() ^ (_nil ? 1024 : 0); } + + @Override + boolean eq(Type t) { + TypeMemPtr ptr = (TypeMemPtr)t; // Invariant + return _ro==ptr._ro && _obj == ptr._obj && _nil == ptr._nil; + } + + // [void,name,MANY]*[,?] + @Override + public StringBuilder print(StringBuilder sb) { + if( this==BOT ) return sb.append("PtrBot"); + if( this==TOP ) return sb.append("PtrTop"); + if( this== NULLPTR) return sb.append("null"); + if( this== VOIDPTR) return sb.append("*void"); + return _obj.print(sb.append("*")).append(_nil ? "?" : ""); + } + + @Override public String str() { + if( this==BOT ) return "PtrBot"; + if( this==TOP ) return "PtrTop"; + if( this== NULLPTR) return "null"; + if( this== VOIDPTR) return "*void"; + return "*"+_obj.str()+(_nil ? "?" : ""); + } + +} diff --git a/chapter17b/src/main/java/com/seaofnodes/simple/type/TypeStruct.java b/chapter17b/src/main/java/com/seaofnodes/simple/type/TypeStruct.java new file mode 100644 index 00000000..97664e3c --- /dev/null +++ b/chapter17b/src/main/java/com/seaofnodes/simple/type/TypeStruct.java @@ -0,0 +1,262 @@ +package com.seaofnodes.simple.type; + +import com.seaofnodes.simple.Utils; +import java.util.ArrayList; + +/** + * Represents a struct type. + */ +public class TypeStruct extends Type { + + // A Struct has a name and a set of fields; the fields themselves have + // names, types and aliases. The name has no semantic meaning, but is + // useful for debugging. Briefly during parsing a Struct can be a + // forward-ref; in this case the _fields array is null. + + // Its illegal to attempt to load a field from a forward-ref struct. + + // Example: "int rez = new S.x; struct S { int x; } return rez;" // Error, S not defined + // Rewrite: "struct S { int x; } int rez = new S.x; return rez;" // Ok, no forward ref + // + // During the normal optimization run, struct types "bottom out" at further + // struct references, so we don't have to handle e.g. cyclic types. The + // "bottom out" is again the forward-ref struct. + public final String _name; + public final Field[] _fields; + + TypeStruct(String name, Field[] fields) { + super(TSTRUCT); + _name = name; + _fields = fields; + } + + // All fields directly listed + public static TypeStruct make(String name, Field... fields) { return new TypeStruct(name, fields).intern(); } + public static final TypeStruct TOP = make("$TOP",new Field[0]); + public static final TypeStruct BOT = make("$BOT",new Field[0]); + public static final TypeStruct TEST = make("test",new Field[]{Field.TEST}); + // Forward-ref version + public static TypeStruct makeFRef(String name) { return make(name, (Field[])null); } + // Make a read-only version + @Override public TypeStruct makeRO() { + if( isFinal() ) return this; + Field[] flds = new Field[_fields.length]; + for( int i=0; i ts) { ts.add(TEST); ts.add(BOT); ts.add(S1); ts.add(S2); ts.add(ARY); } + + // Find field index by name + public int find(String fname) { + for( int i=0; i<_fields.length; i++ ) + if( _fields[i]._fname.equals(fname) ) + return i; + return -1; + } + public Field field(String fname) { + int idx = find(fname); + return idx== -1 ? null : _fields[idx]; + } + + // Find field index by alias + public int findAlias( int alias ) { + for( int i=0; i<_fields.length; i++ ) + if( _fields[i]._alias==alias ) + return i; + return -1; + } + + + @Override + Type xmeet(Type t) { + TypeStruct that = (TypeStruct) t; + if( this==TOP ) return that; + if( that==TOP ) return this; + if( this==BOT ) return BOT; + if( that==BOT ) return BOT; + + // Within the same compilation unit, struct names are unique. If the + // names differ, its different structs. Across many compilation units, + // structs with the same name but different field layouts can be + // interned... which begs the question: + // "What is the meet of structs from two different compilation units?" + // And the answer is: "don't ask". + if( !_name.equals(that._name) ) + return BOT; // It's a struct; that's about all we know + if( this._fields==null ) return that; + if( that._fields==null ) return this; + if( _fields.length != that._fields.length ) return BOT; + // Just do field meets + Field[] flds = new Field[_fields.length]; + for( int i=0; i<_fields.length; i++ ) { + Field f0 = _fields[i], f1 = that._fields[i]; + if( !f0._fname.equals(f1._fname) || f0._alias != f1._alias ) + return BOT; + flds[i] = (Field)f0.meet(f1); + } + return make(_name,flds); + } + + @Override + public TypeStruct dual() { + if( this==TOP ) return BOT; + if( this==BOT ) return TOP; + if( _fields == null ) return this; + Field[] flds = new Field[_fields.length]; + for( int i=0; i<_fields.length; i++ ) + flds[i] = _fields[i].dual(); + return make(_name,flds); + } + + // Keeps the same struct, but lower-bounds all fields. + @Override public TypeStruct glb() { + if( _glb() ) return this; + // Need to glb each field + Field[] flds = new Field[_fields.length]; + for( int i=0; i<_fields.length; i++ ) + flds[i] = _fields[i].glb(); + return make(_name,flds); + } + private boolean _glb() { + if( _fields!=null ) + for( Field f : _fields ) + if( f.glb() != f ) + return false; + return true; + } + @Override public TypeStruct lub() { + if( _lub() ) return this; + // Need to glb each field + Field[] flds = new Field[_fields.length]; + for( int i=0; i<_fields.length; i++ ) + flds[i] = _fields[i].lub(); + return make(_name,flds); + } + private boolean _lub() { + if( _fields!=null ) + for( Field f : _fields ) + if( f.lub() != f ) + return false; + return true; + } + + + // Is forward-reference + @Override public boolean isFRef() { return _fields==null; } + // All fields are final + @Override public boolean isFinal() { + if( _fields==null ) return true; + for( Field fld : _fields ) + if( !fld.isFinal() ) + return false; + return true; + } + + @Override + boolean eq(Type t) { + TypeStruct ts = (TypeStruct)t; // Invariant + if( !_name.equals(ts._name) ) + return false; + if( _fields == ts._fields ) return true; + if( _fields==null || ts._fields==null ) return false; + if( _fields.length!=ts._fields.length ) + return false; + for( int i = 0; i < _fields.length; i++ ) + if( _fields[i] != ts._fields[i] ) + return false; + return true; + } + + @Override + int hash() { + long hash = _name.hashCode(); + if( _fields != null ) + for( Field f : _fields ) + hash = Utils.rot(hash,13) ^ f.hashCode(); + return Utils.fold(hash); + } + + @Override + public StringBuilder print(StringBuilder sb) { + if( this==BOT ) return sb.append("StructBot"); + if( this==TOP ) return sb.append("StructTop"); + sb.append(_name); + if( _fields == null ) return sb; // Forward reference struct, just print the name + sb.append(" {"); + for( Field f : _fields ) + f._type.print(sb).append(f._final ? " " : " !").append(f._fname).append("; "); + return sb.append("}"); + } + + @Override public String str() { + if( this==BOT ) return "StructBot"; + if( this==TOP ) return "StructTop"; + return _name; + } + + + public boolean isAry() { return _fields.length==2 && _fields[1]._fname.equals("[]"); } + + public int aryBase() { + assert isAry(); + if( _offs==null ) _offs = offsets(); + return _offs[1]; + } + public int aryScale() { + assert isAry(); + return _fields[1]._type.log_size(); + } + + + // Field offsets as packed byte offsets + private int[] _offs; // Lazily computed and not part of the type semantics + public int offset(int idx) { + if( _offs==null ) _offs = offsets(); + return _offs[idx]; + } + private int[] offsets() { // Field byte offsets + // Compute a layout for a collection of fields + assert _fields != null; // No forward refs + // Compute a layout + int[] cnts = new int[4]; // Count of fields at log field size + for( Field f : _fields ) + cnts[f._type.log_size()]++; // Log size is 0(byte), 1(i16/u16), 2(i32/f32), 3(i64/dbl) + int off = 0, idx = 0; // Base common struct fields go here, e.g. Mark/Klass + // Compute offsets to the start of each power-of-2 aligned fields. + int[] offs = new int[4]; + for( int i=3; i>=0; i-- ) { + offs[i] = off; + off += cnts[i]<