diff options
Diffstat (limited to 'chapter03')
4 files changed, 5 insertions, 24 deletions
diff --git a/chapter03/README.md b/chapter03/README.md index ddb9fafa..39baf903 100644 --- a/chapter03/README.md +++ b/chapter03/README.md @@ -124,8 +124,9 @@ The variables `a`, `b`, and `c` are registered in this table. * On line 5, a variable `b` is declared. `b` is registered in the symbol table at level 1. This then hides the variable with the same name on line 2. * On line 7, we update the variable `c`. Variable lookup will find it in the symbol table at level 0. -The node graph is shown below (note that peephole opts are switched off here so that we can -see the graph as its initially constructed). +The schematic below shows the variable bindings and arithmetic before constant +folding. The compiler applies peepholes as it builds the graph, so the actual +result of this example is `return 4;`.  diff --git a/chapter03/src/main/java/com/seaofnodes/simple/node/Node.java b/chapter03/src/main/java/com/seaofnodes/simple/node/Node.java index 3922533c..3fa0fd1e 100644 --- a/chapter03/src/main/java/com/seaofnodes/simple/node/Node.java +++ b/chapter03/src/main/java/com/seaofnodes/simple/node/Node.java @@ -211,12 +211,6 @@ public abstract class Node { // Mostly used for asserts and printing. public boolean isDead() { return isUnused() && nIns()==0 && _type==null; } /** - * We allow disabling peephole opt so that we can observe the - * full graph, vs the optimized graph. - */ - public static boolean _disablePeephole = false; - - /** * Try to peephole at this node and return a better replacement Node if * possible. We compute a {@link Type} and then check and replace: * <ul> @@ -241,9 +235,6 @@ public abstract class Node { // Compute initial or improved Type Type type = _type = compute(); - if (_disablePeephole) - return null; // Peephole optimizations turned off - // Replace constant computations from non-constants with a constant node if (!(this instanceof ConstantNode) && type.isConstant()) { kill(); // Kill `this` because replacing with a Constant @@ -283,7 +274,7 @@ public abstract class Node { * 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; _disablePeephole=false; } + public static void reset() { UNIQUE_ID = 1; } /** * Debugging utility to find a Node by index diff --git a/chapter03/src/test/java/com/seaofnodes/simple/Chapter02Test.java b/chapter03/src/test/java/com/seaofnodes/simple/Chapter02Test.java index 9de09d21..6c816a23 100644 --- a/chapter03/src/test/java/com/seaofnodes/simple/Chapter02Test.java +++ b/chapter03/src/test/java/com/seaofnodes/simple/Chapter02Test.java @@ -11,10 +11,8 @@ public class Chapter02Test { @Test public void testParseGrammar() { Parser parser = new Parser("return 1+2*3+-5;"); - Node._disablePeephole = true; // disable peephole so we can observe full graph ReturnNode ret = parser.parse(); - assertEquals("return (1+((2*3)+(-5)));", ret.print()); - Node._disablePeephole = false; + assertEquals("return 2;", ret.print()); } @Test diff --git a/chapter03/src/test/java/com/seaofnodes/simple/Chapter03Test.java b/chapter03/src/test/java/com/seaofnodes/simple/Chapter03Test.java index b42f1433..78696633 100644 --- a/chapter03/src/test/java/com/seaofnodes/simple/Chapter03Test.java +++ b/chapter03/src/test/java/com/seaofnodes/simple/Chapter03Test.java @@ -29,15 +29,6 @@ public class Chapter03Test { } @Test - public void testVarScopeNoPeephole() { - Parser parser = new Parser("int a=1; int b=2; int c=0; { int b=3; c=a+b; } return c; "); - Node._disablePeephole = true; - ReturnNode ret = parser.parse(); - Node._disablePeephole = false; - assertEquals("return (1+3);", ret.print()); - } - - @Test public void testVarDist() { Parser parser = new Parser("int x0=1; int y0=2; int x1=3; int y1=4; return (x0-x1)*(x0-x1) + (y0-y1)*(y0-y1); "); ReturnNode ret = parser.parse(); |