Chapter 6 (#38)

* #37 Create chapter 6 skeleton

* #37 Revise type system - TOP, BOTTOM, CONTROL are now directly implemented in Type, XCONTROL is a new type and that's implemented directly too.
We have a _type field that is like an enum.

* #37 Revise Type.meet() - this is now final.
Subclasses can override xmeet() which is protected but
now handles simple types in Type itself.

* #37 Basic test for peephole of CFG

* #37 Revise compute of if

* #37 Revise compute of if

* #37 WIP peephole of If

* #37 WIP peephole of If

* #37 WIP peephole of If

* #37 WIP peephole of If

* #37 WIP peephole of If

* #37 WIP fix the chars inserted by IntelliJ

* #37 WIP Fix compute type in IfNode

* #37 WIP Null check region inputs

* #37 WIP Fix where we choose great grand parent instead of grand parent
Add new test

* #37 WIP More fixes and tests

* #37 WIP Some minor adjustments

* Cleanup folding dead IF tests

Remove isDeadCtrl & just test for the constant.
Remove DEAD_CTRL, doesn't properly reset between tests.
Move keep/unkeep to Node.
PhiNode has a proper compute() call.
ProjNode ideal is a lot simpler.
Region doesn't ever get a null.
Move the mergeScopes Region peep till after all Phis are added.
Type TOP and XCONTROL count as constants.
TypeTuple gets a toString

* #37 WIP Upate README

* #37 WIP Region node should check if one of its inputs is a region that needs to be peepholed

* #37 WIP If node should check if its ctrl input is a Region that has only 1 live input so can be peepholed

* #37 WIP Further update to README to make the peephole logic clearer. Also discuss the relationship between Region and Phi nodes

* Region removes dead input paths

Remove region-folding in Return, If.
Add a Makefile.
Reformat triple-quote lines to be emacs-friendly.

* StopNode idealize

Return type sharpens to include control input.

* Remove !=, >=, >; use Not and <, <=, ==

Fix bug mixing rotating different ops.
Generalize Add fold constants; apply to Mul, EQ.
Fix Div.copy

* Fix bug rotating e.g. < or <=

Peep is only valid for associative ops

* #37 WIP Doc updates

* Work over the Ch6 Readme

Major issue: Region inputs align 1-to-1 with Phi inputs, but a Region can have zero to many Phis.  When we lose a Region input (dead path), we need to lose the same inputs to each Phi - but we don't lose the Phis themselves, unless we're folding away down to the last live input.

* Update chapter06/README.md

Co-authored-by: Yichen Yan <oraluben@outlook.com>

* Update chapter06/README.md

Co-authored-by: Yichen Yan <oraluben@outlook.com>

* #37 Backport type system changes to chapter 2

* #37 Backport type system changes to chapter 3

* #37 Backport type system changes to chapter 4

* #37 Backport type system changes to chapter 5

* #37 Merge chapter 5 updates from main.
Remove language grammar module as we describe the grammar incrementally in each chapter.

* #37 Chapter 6 doc updates - added visuals to show effects of CFG peephole

* #37 Sync some updates to chapter 2

* #37 Sync some updates to chapter 3

* #37 Sync some updates to chapter 4

---------

Co-authored-by: Cliff Click <cliffc@acm.org>
Co-authored-by: Yichen Yan <oraluben@outlook.com>

5 files changed, 0 insertions, 304 deletions

diff --git a/language/.gitignore b/language/.gitignore
deleted file mode 100644
index 58314a2c..00000000
--- a/language/.gitignore
+++ /dev/null
@@ -1,28 +0,0 @@
-# Compiled class file
-*.class
-
-# Log file
-*.log
-
-# BlueJ files
-*.ctxt
-
-# Mobile Tools for Java (J2ME)
-.mtj.tmp/
-
-# Package Files #
-*.jar
-*.war
-*.nar
-*.ear
-*.zip
-*.tar.gz
-*.rar
-
-# virtual machine crash logs, see http://www.java.com/en/download/help/error_hotspot.xml
-hs_err_pid*
-
-target/*
-
-.idea
-*.iml
\ No newline at end of file
diff --git a/language/README.md b/language/README.md
deleted file mode 100644
index 09593ab5..00000000
--- a/language/README.md
+++ /dev/null
@@ -1,6 +0,0 @@
-# Simple Demo Language
-
-The language is a small subset of the C language.
-
-The grammar of the language is not yet finalized, but for the current definition,
-please look at [grammar](src/main/antlr4/com/seaofnodes/simple/antlr/SimpleLanguage.g4).
\ No newline at end of file
diff --git a/language/examples/all-features.lang b/language/examples/all-features.lang
deleted file mode 100644
index 132e4b9c..00000000
--- a/language/examples/all-features.lang
+++ /dev/null
@@ -1,21 +0,0 @@
-int i;
-int j;
-
-i = 0;
-j = 100;
-while ( 1 )
-{
-    i = i + 1;
-    j = j - 1;
-    if (i >= j)
-        break;
-}
-
-if (1)
-    i = i + 5;
-else if (2)
-    i = i - 1;
-else
-{
-    j = 0;
-}
\ No newline at end of file
diff --git a/language/pom.xml b/language/pom.xml
deleted file mode 100644
index dbb4710e..00000000
--- a/language/pom.xml
+++ /dev/null
@@ -1,79 +0,0 @@
-<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
-	xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
-	<modelVersion>4.0.0</modelVersion>
-    <parent>
-        <groupId>com.seaofnodes</groupId>
-        <artifactId>simple</artifactId>
-        <version>1.0</version>
-    </parent>
-	<artifactId>language-grammar</artifactId>
-	<packaging>jar</packaging>
-	<name>SeaOfNodes Demo Simple Language Grammar</name>
-	<properties>
-		<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
-		<maven.compiler.target>21</maven.compiler.target>
-		<maven.compiler.source>21</maven.compiler.source>
-		<antlr4test-maven-plugin.version>1.22</antlr4test-maven-plugin.version>
-		<antlr.version>4.11.1</antlr.version>
-		<junit.version>4.13.2</junit.version>
-	</properties>
-	<dependencies>
-		<dependency>
-			<groupId>org.antlr</groupId>
-			<artifactId>antlr4-runtime</artifactId>
-			<version>${antlr.version}</version>
-			<type>jar</type>
-			<scope>compile</scope>
-		</dependency>
-	</dependencies>
-	<build>
-		<pluginManagement>
-			<plugins>
-				<plugin>
-					<groupId>org.apache.maven.plugins</groupId>
-					<artifactId>maven-compiler-plugin</artifactId>
-					<version>3.10.1</version>
-				</plugin>
-			</plugins>
-		</pluginManagement>
-		<plugins>
-			<plugin>
-				<groupId>org.antlr</groupId>
-				<artifactId>antlr4-maven-plugin</artifactId>
-				<version>${antlr.version}</version>
-				<configuration>
-					<visitor>true</visitor>
-					<listener>true</listener>
-				</configuration>
-				<executions>
-					<execution>
-						<phase>generate-sources</phase>
-						<goals>
-							<goal>antlr4</goal>
-						</goals>
-					</execution>
-				</executions>
-			</plugin>
-			<plugin>
-				<groupId>com.khubla.antlr</groupId>
-				<artifactId>antlr4test-maven-plugin</artifactId>
-				<version>${antlr4test-maven-plugin.version}</version>
-				<configuration>
-					<verbose>false</verbose>
-					<showTree>false</showTree>
-					<entryPoint>program</entryPoint>
-					<grammarName>SimpleLanguage</grammarName>
-					<packageName>com.seaofnodes.simple.antlr</packageName>
-					<exampleFiles>examples/</exampleFiles>
-				</configuration>
-				<executions>
-					<execution>
-						<goals>
-							<goal>test</goal>
-						</goals>
-					</execution>
-				</executions>
-			</plugin>
-		</plugins>
-	</build>
-</project>
diff --git a/language/src/main/antlr4/com/seaofnodes/simple/antlr/SimpleLanguage.g4 b/language/src/main/antlr4/com/seaofnodes/simple/antlr/SimpleLanguage.g4
deleted file mode 100644
index 6779e5a2..00000000
--- a/language/src/main/antlr4/com/seaofnodes/simple/antlr/SimpleLanguage.g4
+++ /dev/null
@@ -1,170 +0,0 @@
-grammar SimpleLanguage;
-
-program
-    : declaration* statement+ EOF
-    ;
-
-declaration
-    : type IDENTIFIER ';'
-    ;
-
-type
-    : 'int'
-    ;
-
-statement
-    : 'if' '(' expression ')' statement
-    | 'if' '(' expression ')' statement 'else' statement
-    | 'while' '(' expression ')' statement
-    | IDENTIFIER '=' expression ';'
-    | '{' declaration* statement+ '}'
-    | 'break' ';'
-    ;
-
-expression
-    : primaryExpression                                             # PrimaryExpression_
-    | ('-' | '!') expression                                        # UnaryExpression
-    | expression ('*' | '/' ) expression                            # ArithmeticOrLogicalExpression
-    | expression ('+' | '-') expression                             # ArithmeticOrLogicalExpression
-    | expression ('==' | '!='| '>'| '<'| '>='| '<=') expression     # ComparisonExpression
-    | expression '&&' expression                                    # BooleanExpression
-    | expression '||' expression                                    # BooleanExpression
-    ;
-
-primaryExpression
-    :
-    | INTEGER_LITERAL
-    | IDENTIFIER
-    | '(' expression ')'
-    ;
-
-///////////////////////////////////////////////////////////////////
-
-IDENTIFIER
-    :   IDENTIFIER_NONDIGIT
-        (   IDENTIFIER_NONDIGIT
-        |   DEC_DIGIT
-        )*
-    ;
-
-fragment
-IDENTIFIER_NONDIGIT
-    :   NON_DIGIT
-    |   UNIVERSAL_CHARACTER_NAME
-    ;
-
-fragment
-NON_DIGIT
-    :   [a-zA-Z_]
-    ;
-
-
-fragment
-UNIVERSAL_CHARACTER_NAME
-    :   '\\u' HEX_QUAD
-    |   '\\U' HEX_QUAD HEX_QUAD
-    ;
-
-fragment
-HEX_QUAD
-    :   HEX_DIGIT HEX_DIGIT HEX_DIGIT HEX_DIGIT
-    ;
-
-// tokens char and string
-CHAR_LITERAL
-   : '\''
-   (
-      ~['\\\n\r\t]
-      | QUOTE_ESCAPE
-      | ASCII_ESCAPE
-      | UNICODE_ESCAPE
-   ) '\''
-   ;
-
-STRING_LITERAL
-   : '"'
-   (
-      ~["]
-      | QUOTE_ESCAPE
-      | ASCII_ESCAPE
-      | UNICODE_ESCAPE
-      | ESC_NEWLINE
-   )* '"'
-   ;
-RAW_STRING_LITERAL: 'r' RAW_STRING_CONTENT;
-fragment RAW_STRING_CONTENT: '#' RAW_STRING_CONTENT '#' | '"' .*? '"';
-BYTE_LITERAL: 'b\'' (. | QUOTE_ESCAPE | BYTE_ESCAPE) '\'';
-
-BYTE_STRING_LITERAL: 'b"' (~["] | QUOTE_ESCAPE | BYTE_ESCAPE)* '"';
-RAW_BYTE_STRING_LITERAL: 'br' RAW_STRING_CONTENT;
-fragment ASCII_ESCAPE: '\\x' OCT_DIGIT HEX_DIGIT | COMMON_ESCAPE;
-fragment BYTE_ESCAPE: '\\x' HEX_DIGIT HEX_DIGIT | COMMON_ESCAPE;
-fragment COMMON_ESCAPE: '\\' [nrt\\0];
-fragment UNICODE_ESCAPE
-   : '\\u{' HEX_DIGIT HEX_DIGIT? HEX_DIGIT? HEX_DIGIT? HEX_DIGIT? HEX_DIGIT? '}'
-   ;
-fragment QUOTE_ESCAPE: '\\' ['"];
-fragment ESC_NEWLINE: '\\' '\n';
-
-// number
-INTEGER_LITERAL
-   :
-   (
-      DEC_LITERAL
-      | BIN_LITERAL
-      | OCT_LITERAL
-      | HEX_LITERAL
-   ) INTEGER_SUFFIX?
-   ;
-DEC_LITERAL: DEC_DIGIT (DEC_DIGIT | '_')*;
-HEX_LITERAL: '0x' '_'* HEX_DIGIT (HEX_DIGIT | '_')*;
-OCT_LITERAL: '0o' '_'* OCT_DIGIT (OCT_DIGIT | '_')*;
-BIN_LITERAL: '0b' '_'* [01] [01_]*;
-FLOAT_LITERAL
-   : DEC_LITERAL
-   (
-      '.' DEC_LITERAL
-   )? FLOAT_EXPONENT? FLOAT_SUFFIX?
-   ;
-
-fragment INTEGER_SUFFIX
-   : 'u8'
-   | 'u16'
-   | 'u32'
-   | 'u64'
-   | 'u128'
-   | 'usize'
-   | 'i8'
-   | 'i16'
-   | 'i32'
-   | 'i64'
-   | 'i128'
-   | 'isize'
-   ;
-
-fragment FLOAT_SUFFIX: 'f32' | 'f64';
-fragment FLOAT_EXPONENT: [eE] [+-]? '_'* DEC_LITERAL;
-fragment OCT_DIGIT: [0-7];
-fragment DEC_DIGIT: [0-9];
-fragment HEX_DIGIT: [0-9a-fA-F];
-
-
-WHITESPACE
-    :   [ \t]+
-        -> skip
-    ;
-
-NEWLINE
-    :   (   '\r' '\n'?
-        |   '\n'
-        )
-        -> skip
-    ;
-
-LINE_COMMENT
-    :   '//' ~[\r\n]*
-        -> skip
-    ;
-
-
-ANY: . ;
\ No newline at end of file