First steps towards better code generation for LBranch:

 * AST Expression nodes get a separate testing ID to record type info in
   ToBooleanStub later. This is necessary to avoid clashes with other uses of
   already existing IDs.

 * In order to avoid threading the condition expression through tons of places,
   TestContexts carry it now with them. Note that we will probably only need the
   testing ID of the expression, but having the whole thing at hand makes
   debugging easier. Probably we will change this later...
Review URL: http://codereview.chromium.org/7046073

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@8274 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

diff --git a/src/arm/full-codegen-arm.cc b/src/arm/full-codegen-arm.cc
index 749d1f5..31d2b92 100644 (file)
--- a/src/arm/full-codegen-arm.cc
+++ b/src/arm/full-codegen-arm.cc
@@ -383,7 +383,7 @@ void FullCodeGenerator::TestContext::Plug(Slot* slot) const {
   // For simplicity we always test the accumulator register.
   codegen()->Move(result_register(), slot);
   codegen()->PrepareForBailoutBeforeSplit(TOS_REG, false, NULL, NULL);
-  codegen()->DoTest(true_label_, false_label_, fall_through_);
+  codegen()->DoTest(this);
 }
 
 
@@ -417,7 +417,7 @@ void FullCodeGenerator::TestContext::Plug(Heap::RootListIndex index) const {
     if (true_label_ != fall_through_) __ b(true_label_);
   } else {
     __ LoadRoot(result_register(), index);
-    codegen()->DoTest(true_label_, false_label_, fall_through_);
+    codegen()->DoTest(this);
   }
 }
 
@@ -464,7 +464,7 @@ void FullCodeGenerator::TestContext::Plug(Handle<Object> lit) const {
   } else {
     // For simplicity we always test the accumulator register.
     __ mov(result_register(), Operand(lit));
-    codegen()->DoTest(true_label_, false_label_, fall_through_);
+    codegen()->DoTest(this);
   }
 }
 
@@ -500,7 +500,7 @@ void FullCodeGenerator::TestContext::DropAndPlug(int count,
   __ Drop(count);
   __ Move(result_register(), reg);
   codegen()->PrepareForBailoutBeforeSplit(TOS_REG, false, NULL, NULL);
-  codegen()->DoTest(true_label_, false_label_, fall_through_);
+  codegen()->DoTest(this);
 }
 
 
@@ -578,7 +578,8 @@ void FullCodeGenerator::TestContext::Plug(bool flag) const {
 }
 
 
-void FullCodeGenerator::DoTest(Label* if_true,
+void FullCodeGenerator::DoTest(Expression* condition,
+                               Label* if_true,
                                Label* if_false,
                                Label* fall_through) {
   if (CpuFeatures::IsSupported(VFP3)) {

diff --git a/src/ast.h b/src/ast.h
index 12b2024..56bda6b 100644 (file)
--- a/src/ast.h
+++ b/src/ast.h
@@ -210,7 +210,7 @@ class Expression: public AstNode {
     kTest
   };
 
-  Expression() : id_(GetNextId()) {}
+  Expression() : id_(GetNextId()), test_id_(GetNextId()) {}
 
   virtual int position() const {
     UNREACHABLE();
@@ -262,9 +262,11 @@ class Expression: public AstNode {
   }
 
   unsigned id() const { return id_; }
+  unsigned test_id() const { return test_id_; }
 
  private:
   unsigned id_;
+  unsigned test_id_;
 };
 
 

diff --git a/src/full-codegen.cc b/src/full-codegen.cc
index 52cb501..f6d673b 100644 (file)
--- a/src/full-codegen.cc
+++ b/src/full-codegen.cc
@@ -441,7 +441,7 @@ void FullCodeGenerator::TestContext::Plug(Register reg) const {
   // For simplicity we always test the accumulator register.
   __ Move(result_register(), reg);
   codegen()->PrepareForBailoutBeforeSplit(TOS_REG, false, NULL, NULL);
-  codegen()->DoTest(true_label_, false_label_, fall_through_);
+  codegen()->DoTest(this);
 }
 
 
@@ -463,7 +463,7 @@ void FullCodeGenerator::TestContext::PlugTOS() const {
   // For simplicity we always test the accumulator register.
   __ pop(result_register());
   codegen()->PrepareForBailoutBeforeSplit(TOS_REG, false, NULL, NULL);
-  codegen()->DoTest(true_label_, false_label_, fall_through_);
+  codegen()->DoTest(this);
 }
 
 
@@ -513,6 +513,14 @@ void FullCodeGenerator::TestContext::PrepareTest(
 }
 
 
+void FullCodeGenerator::DoTest(const TestContext* context) {
+  DoTest(context->condition(),
+         context->true_label(),
+         context->false_label(),
+         context->fall_through());
+}
+
+
 void FullCodeGenerator::VisitDeclarations(
     ZoneList<Declaration*>* declarations) {
   int length = declarations->length();
@@ -734,9 +742,9 @@ void FullCodeGenerator::VisitLogicalExpression(BinaryOperation* expr) {
     Label discard, restore;
     PrepareForBailoutBeforeSplit(TOS_REG, false, NULL, NULL);
     if (is_logical_and) {
-      DoTest(&discard, &restore, &restore);
+      DoTest(left, &discard, &restore, &restore);
     } else {
-      DoTest(&restore, &discard, &restore);
+      DoTest(left, &restore, &discard, &restore);
     }
     __ bind(&restore);
     __ pop(result_register());
@@ -753,9 +761,9 @@ void FullCodeGenerator::VisitLogicalExpression(BinaryOperation* expr) {
     Label discard;
     PrepareForBailoutBeforeSplit(TOS_REG, false, NULL, NULL);
     if (is_logical_and) {
-      DoTest(&discard, &done, &discard);
+      DoTest(left, &discard, &done, &discard);
     } else {
-      DoTest(&done, &discard, &discard);
+      DoTest(left, &done, &discard, &discard);
     }
     __ bind(&discard);
     __ Drop(1);

diff --git a/src/full-codegen.h b/src/full-codegen.h
index fc0fe6d..87951eb 100644 (file)
--- a/src/full-codegen.h
+++ b/src/full-codegen.h
@@ -113,6 +113,7 @@ class FullCodeGenerator: public AstVisitor {
   class TryFinally;
   class Finally;
   class ForIn;
+  class TestContext;
 
   class NestedStatement BASE_EMBEDDED {
    public:
@@ -298,7 +299,11 @@ class FullCodeGenerator: public AstVisitor {
   // Helper function to convert a pure value into a test context.  The value
   // is expected on the stack or the accumulator, depending on the platform.
   // See the platform-specific implementation for details.
-  void DoTest(Label* if_true, Label* if_false, Label* fall_through);
+  void DoTest(Expression* condition,
+              Label* if_true,
+              Label* if_false,
+              Label* fall_through);
+  void DoTest(const TestContext* context);
 
   // Helper function to split control flow and avoid a branch to the
   // fall-through label if it is set up.
@@ -347,7 +352,7 @@ class FullCodeGenerator: public AstVisitor {
                        Label* if_true,
                        Label* if_false,
                        Label* fall_through) {
-    TestContext context(this, if_true, if_false, fall_through);
+    TestContext context(this, expr, if_true, if_false, fall_through);
     VisitInCurrentContext(expr);
   }
 
@@ -670,11 +675,13 @@ class FullCodeGenerator: public AstVisitor {
 
   class TestContext : public ExpressionContext {
    public:
-    explicit TestContext(FullCodeGenerator* codegen,
-                         Label* true_label,
-                         Label* false_label,
-                         Label* fall_through)
+    TestContext(FullCodeGenerator* codegen,
+                Expression* condition,
+                Label* true_label,
+                Label* false_label,
+                Label* fall_through)
         : ExpressionContext(codegen),
+          condition_(condition),
           true_label_(true_label),
           false_label_(false_label),
           fall_through_(fall_through) { }
@@ -684,6 +691,7 @@ class FullCodeGenerator: public AstVisitor {
       return reinterpret_cast<const TestContext*>(context);
     }
 
+    Expression* condition() const { return condition_; }
     Label* true_label() const { return true_label_; }
     Label* false_label() const { return false_label_; }
     Label* fall_through() const { return fall_through_; }
@@ -704,6 +712,7 @@ class FullCodeGenerator: public AstVisitor {
     virtual bool IsTest() const { return true; }
 
    private:
+    Expression* condition_;
     Label* true_label_;
     Label* false_label_;
     Label* fall_through_;

diff --git a/src/hydrogen.cc b/src/hydrogen.cc
index 9b4f615..9564eb6 100644 (file)
--- a/src/hydrogen.cc
+++ b/src/hydrogen.cc
@@ -2007,9 +2007,10 @@ FunctionState::FunctionState(HGraphBuilder* owner,
       HBasicBlock* if_false = owner->graph()->CreateBasicBlock();
       if_true->MarkAsInlineReturnTarget();
       if_false->MarkAsInlineReturnTarget();
+      Expression* cond = TestContext::cast(owner->ast_context())->condition();
       // The AstContext constructor pushed on the context stack.  This newed
       // instance is the reason that AstContext can't be BASE_EMBEDDED.
-      test_context_ = new TestContext(owner, if_true, if_false);
+      test_context_ = new TestContext(owner, cond, if_true, if_false);
     } else {
       function_return_ = owner->graph()->CreateBasicBlock();
       function_return()->MarkAsInlineReturnTarget();
@@ -2179,7 +2180,7 @@ void HGraphBuilder::VisitForTypeOf(Expression* expr) {
 void HGraphBuilder::VisitForControl(Expression* expr,
                                     HBasicBlock* true_block,
                                     HBasicBlock* false_block) {
-  TestContext for_test(this, true_block, false_block);
+  TestContext for_test(this, expr, true_block, false_block);
   Visit(expr);
 }
 

diff --git a/src/hydrogen.h b/src/hydrogen.h
index ac06fb0..366364f 100644 (file)
--- a/src/hydrogen.h
+++ b/src/hydrogen.h
@@ -551,9 +551,11 @@ class ValueContext: public AstContext {
 class TestContext: public AstContext {
  public:
   TestContext(HGraphBuilder* owner,
+              Expression* condition,
               HBasicBlock* if_true,
               HBasicBlock* if_false)
       : AstContext(owner, Expression::kTest),
+        condition_(condition),
         if_true_(if_true),
         if_false_(if_false) {
   }
@@ -566,6 +568,7 @@ class TestContext: public AstContext {
     return reinterpret_cast<TestContext*>(context);
   }
 
+  Expression* condition() const { return condition_; }
   HBasicBlock* if_true() const { return if_true_; }
   HBasicBlock* if_false() const { return if_false_; }
 
@@ -574,6 +577,7 @@ class TestContext: public AstContext {
   // control flow.
   void BuildBranch(HValue* value);
 
+  Expression* condition_;
   HBasicBlock* if_true_;
   HBasicBlock* if_false_;
 };

diff --git a/src/ia32/full-codegen-ia32.cc b/src/ia32/full-codegen-ia32.cc
index 8e8fcd2..8711794 100644 (file)
--- a/src/ia32/full-codegen-ia32.cc
+++ b/src/ia32/full-codegen-ia32.cc
@@ -374,7 +374,7 @@ void FullCodeGenerator::TestContext::Plug(Slot* slot) const {
   // For simplicity we always test the accumulator register.
   codegen()->Move(result_register(), slot);
   codegen()->PrepareForBailoutBeforeSplit(TOS_REG, false, NULL, NULL);
-  codegen()->DoTest(true_label_, false_label_, fall_through_);
+  codegen()->DoTest(this);
 }
 
 
@@ -448,7 +448,7 @@ void FullCodeGenerator::TestContext::Plug(Handle<Object> lit) const {
   } else {
     // For simplicity we always test the accumulator register.
     __ mov(result_register(), lit);
-    codegen()->DoTest(true_label_, false_label_, fall_through_);
+    codegen()->DoTest(this);
   }
 }
 
@@ -484,7 +484,7 @@ void FullCodeGenerator::TestContext::DropAndPlug(int count,
   __ Drop(count);
   __ Move(result_register(), reg);
   codegen()->PrepareForBailoutBeforeSplit(TOS_REG, false, NULL, NULL);
-  codegen()->DoTest(true_label_, false_label_, fall_through_);
+  codegen()->DoTest(this);
 }
 
 
@@ -561,7 +561,8 @@ void FullCodeGenerator::TestContext::Plug(bool flag) const {
 }
 
 
-void FullCodeGenerator::DoTest(Label* if_true,
+void FullCodeGenerator::DoTest(Expression* condition,
+                               Label* if_true,
                                Label* if_false,
                                Label* fall_through) {
   ToBooleanStub stub;

diff --git a/src/x64/full-codegen-x64.cc b/src/x64/full-codegen-x64.cc
index 746d18c..6c2aa3e 100644 (file)
--- a/src/x64/full-codegen-x64.cc
+++ b/src/x64/full-codegen-x64.cc
@@ -377,7 +377,7 @@ void FullCodeGenerator::StackValueContext::Plug(Slot* slot) const {
 void FullCodeGenerator::TestContext::Plug(Slot* slot) const {
   codegen()->Move(result_register(), slot);
   codegen()->PrepareForBailoutBeforeSplit(TOS_REG, false, NULL, NULL);
-  codegen()->DoTest(true_label_, false_label_, fall_through_);
+  codegen()->DoTest(this);
 }
 
 
@@ -410,7 +410,7 @@ void FullCodeGenerator::TestContext::Plug(Heap::RootListIndex index) const {
     if (true_label_ != fall_through_) __ jmp(true_label_);
   } else {
     __ LoadRoot(result_register(), index);
-    codegen()->DoTest(true_label_, false_label_, fall_through_);
+    codegen()->DoTest(this);
   }
 }
 
@@ -455,7 +455,7 @@ void FullCodeGenerator::TestContext::Plug(Handle<Object> lit) const {
   } else {
     // For simplicity we always test the accumulator register.
     __ Move(result_register(), lit);
-    codegen()->DoTest(true_label_, false_label_, fall_through_);
+    codegen()->DoTest(this);
   }
 }
 
@@ -491,7 +491,7 @@ void FullCodeGenerator::TestContext::DropAndPlug(int count,
   __ Drop(count);
   __ Move(result_register(), reg);
   codegen()->PrepareForBailoutBeforeSplit(TOS_REG, false, NULL, NULL);
-  codegen()->DoTest(true_label_, false_label_, fall_through_);
+  codegen()->DoTest(this);
 }
 
 
@@ -566,7 +566,8 @@ void FullCodeGenerator::TestContext::Plug(bool flag) const {
 }
 
 
-void FullCodeGenerator::DoTest(Label* if_true,
+void FullCodeGenerator::DoTest(Expression* condition,
+                               Label* if_true,
                                Label* if_false,
                                Label* fall_through) {
   ToBooleanStub stub;