Remove extranous holder load in some prototype-chain checking cases

R=ulan@chromium.org

Review URL: https://codereview.chromium.org/13620003

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@14136 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

diff --git a/src/arm/lithium-arm.cc b/src/arm/lithium-arm.cc
index f2b65ef..32daff0 100644 (file)
--- a/src/arm/lithium-arm.cc
+++ b/src/arm/lithium-arm.cc
@@ -1933,7 +1933,7 @@ LInstruction* LChunkBuilder::DoCheckPrototypeMaps(HCheckPrototypeMaps* instr) {
   LUnallocated* temp1 = TempRegister();
   LOperand* temp2 = TempRegister();
   LCheckPrototypeMaps* result = new(zone()) LCheckPrototypeMaps(temp1, temp2);
-  return AssignEnvironment(Define(result, temp1));
+  return AssignEnvironment(result);
 }
 
 

diff --git a/src/arm/lithium-arm.h b/src/arm/lithium-arm.h
index 207faf4..cc97948 100644 (file)
--- a/src/arm/lithium-arm.h
+++ b/src/arm/lithium-arm.h
@@ -2239,7 +2239,7 @@ class LCheckMaps: public LTemplateInstruction<0, 1, 0> {
 };
 
 
-class LCheckPrototypeMaps: public LTemplateInstruction<1, 0, 2> {
+class LCheckPrototypeMaps: public LTemplateInstruction<0, 0, 2> {
  public:
   LCheckPrototypeMaps(LOperand* temp, LOperand* temp2)  {
     temps_[0] = temp;

diff --git a/src/arm/lithium-codegen-arm.cc b/src/arm/lithium-codegen-arm.cc
index 7bb3535..02fac88 100644 (file)
--- a/src/arm/lithium-codegen-arm.cc
+++ b/src/arm/lithium-codegen-arm.cc
@@ -5541,7 +5541,6 @@ void LCodeGen::DoClampTToUint8(LClampTToUint8* instr) {
 
 
 void LCodeGen::DoCheckPrototypeMaps(LCheckPrototypeMaps* instr) {
-  ASSERT(instr->temp()->Equals(instr->result()));
   Register prototype_reg = ToRegister(instr->temp());
   Register map_reg = ToRegister(instr->temp2());
 
@@ -5554,8 +5553,6 @@ void LCodeGen::DoCheckPrototypeMaps(LCheckPrototypeMaps* instr) {
     for (int i = 0; i < maps->length(); i++) {
       prototype_maps_.Add(maps->at(i), info()->zone());
     }
-    __ LoadHeapObject(prototype_reg,
-                      prototypes->at(prototypes->length() - 1));
   } else {
     for (int i = 0; i < prototypes->length(); i++) {
       __ LoadHeapObject(prototype_reg, prototypes->at(i));

diff --git a/src/hydrogen.cc b/src/hydrogen.cc
index abff7b7..bb56296 100644 (file)
--- a/src/hydrogen.cc
+++ b/src/hydrogen.cc
@@ -7113,8 +7113,10 @@ HInstruction* HOptimizedGraphBuilder::BuildLoadNamedMonomorphic(
     Handle<JSObject> holder(lookup.holder());
     Handle<Map> holder_map(holder->map());
     AddCheckMap(object, map);
-    HInstruction* holder_value = AddInstruction(
+    AddInstruction(
         new(zone()) HCheckPrototypeMaps(prototype, holder, zone()));
+    HValue* holder_value = AddInstruction(
+            new(zone()) HConstant(holder, Representation::Tagged()));
     return BuildLoadNamedField(holder_value, holder_map, &lookup);
   }
 

diff --git a/src/ia32/lithium-codegen-ia32.cc b/src/ia32/lithium-codegen-ia32.cc
index 4d23aef..5a69ed0 100644 (file)
--- a/src/ia32/lithium-codegen-ia32.cc
+++ b/src/ia32/lithium-codegen-ia32.cc
@@ -5415,7 +5415,6 @@ void LCodeGen::DoClampTToUint8(LClampTToUint8* instr) {
 
 
 void LCodeGen::DoCheckPrototypeMaps(LCheckPrototypeMaps* instr) {
-  ASSERT(instr->temp()->Equals(instr->result()));
   Register reg = ToRegister(instr->temp());
 
   ZoneList<Handle<JSObject> >* prototypes = instr->prototypes();
@@ -5423,15 +5422,10 @@ void LCodeGen::DoCheckPrototypeMaps(LCheckPrototypeMaps* instr) {
 
   ASSERT(prototypes->length() == maps->length());
 
-  // TODO(ulan): Move this check to hydrogen and split HCheckPrototypeMaps
-  // into two instruction: one that checks the prototypes and another that
-  // loads the holder (HConstant). Find a way to do it without breaking
-  // parallel recompilation.
   if (instr->hydrogen()->CanOmitPrototypeChecks()) {
     for (int i = 0; i < maps->length(); i++) {
       prototype_maps_.Add(maps->at(i), info()->zone());
     }
-    __ LoadHeapObject(reg, prototypes->at(prototypes->length() - 1));
   } else {
     for (int i = 0; i < prototypes->length(); i++) {
       __ LoadHeapObject(reg, prototypes->at(i));

diff --git a/src/ia32/lithium-ia32.cc b/src/ia32/lithium-ia32.cc
index 102515a..a4b1b86 100644 (file)
--- a/src/ia32/lithium-ia32.cc
+++ b/src/ia32/lithium-ia32.cc
@@ -1947,7 +1947,7 @@ LInstruction* LChunkBuilder::DoCheckInstanceType(HCheckInstanceType* instr) {
 LInstruction* LChunkBuilder::DoCheckPrototypeMaps(HCheckPrototypeMaps* instr) {
   LUnallocated* temp = TempRegister();
   LCheckPrototypeMaps* result = new(zone()) LCheckPrototypeMaps(temp);
-  return AssignEnvironment(Define(result, temp));
+  return AssignEnvironment(result);
 }
 
 

diff --git a/src/ia32/lithium-ia32.h b/src/ia32/lithium-ia32.h
index 1c490bb..4c188c3 100644 (file)
--- a/src/ia32/lithium-ia32.h
+++ b/src/ia32/lithium-ia32.h
@@ -2313,7 +2313,7 @@ class LCheckMaps: public LTemplateInstruction<0, 1, 0> {
 };
 
 
-class LCheckPrototypeMaps: public LTemplateInstruction<1, 0, 1> {
+class LCheckPrototypeMaps: public LTemplateInstruction<0, 0, 1> {
  public:
   explicit LCheckPrototypeMaps(LOperand* temp)  {
     temps_[0] = temp;

diff --git a/src/x64/lithium-codegen-x64.cc b/src/x64/lithium-codegen-x64.cc
index 817a9d3..56d8615 100644 (file)
--- a/src/x64/lithium-codegen-x64.cc
+++ b/src/x64/lithium-codegen-x64.cc
@@ -4977,7 +4977,6 @@ void LCodeGen::DoClampTToUint8(LClampTToUint8* instr) {
 
 
 void LCodeGen::DoCheckPrototypeMaps(LCheckPrototypeMaps* instr) {
-  ASSERT(instr->temp()->Equals(instr->result()));
   Register reg = ToRegister(instr->temp());
 
   ZoneList<Handle<JSObject> >* prototypes = instr->prototypes();
@@ -4989,7 +4988,6 @@ void LCodeGen::DoCheckPrototypeMaps(LCheckPrototypeMaps* instr) {
     for (int i = 0; i < maps->length(); i++) {
       prototype_maps_.Add(maps->at(i), info()->zone());
     }
-    __ LoadHeapObject(reg, prototypes->at(prototypes->length() - 1));
   } else {
     for (int i = 0; i < prototypes->length(); i++) {
       __ LoadHeapObject(reg, prototypes->at(i));

diff --git a/src/x64/lithium-x64.cc b/src/x64/lithium-x64.cc
index 9a3166e..3b82b47 100644 (file)
--- a/src/x64/lithium-x64.cc
+++ b/src/x64/lithium-x64.cc
@@ -1843,7 +1843,7 @@ LInstruction* LChunkBuilder::DoCheckInstanceType(HCheckInstanceType* instr) {
 LInstruction* LChunkBuilder::DoCheckPrototypeMaps(HCheckPrototypeMaps* instr) {
   LUnallocated* temp = TempRegister();
   LCheckPrototypeMaps* result = new(zone()) LCheckPrototypeMaps(temp);
-  return AssignEnvironment(Define(result, temp));
+  return AssignEnvironment(result);
 }
 
 

diff --git a/src/x64/lithium-x64.h b/src/x64/lithium-x64.h
index 051f9a4..6ec89fc 100644 (file)
--- a/src/x64/lithium-x64.h
+++ b/src/x64/lithium-x64.h
@@ -2158,7 +2158,7 @@ class LCheckMaps: public LTemplateInstruction<0, 1, 0> {
 };
 
 
-class LCheckPrototypeMaps: public LTemplateInstruction<1, 0, 1> {
+class LCheckPrototypeMaps: public LTemplateInstruction<0, 0, 1> {
  public:
   explicit LCheckPrototypeMaps(LOperand* temp)  {
     temps_[0] = temp;