Make sure transitioned arrays efficiently call builtin Array functions

Loosen the requirement for Map equivalency on several map checks, including checks up the prototype chain, that are not sensitive to ElementsKinds. These selected map checks should also match against FAST_DOUBLE_ELEMENT and FAST_ELEMENT transitions of the original map. This specifically helps all variants of transitioned JSArrays to still efficiently call builtins like push, pop and sort.

BUG=none
TEST=none

Review URL: http://codereview.chromium.org/9015020

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@10331 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

diff --git a/src/arm/lithium-codegen-arm.cc b/src/arm/lithium-codegen-arm.cc
index e1e35d251ec58c3172e6b696de0a6e0f3d352799..e79caf1854b978711411a9fa434b6bff464c12ed 100644 (file)
--- a/src/arm/lithium-codegen-arm.cc
+++ b/src/arm/lithium-codegen-arm.cc
@@ -1,4 +1,4 @@
-// Copyright 2011 the V8 project authors. All rights reserved.
+// Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
@@ -4155,14 +4155,26 @@ void LCodeGen::DoCheckFunction(LCheckFunction* instr) {
 }
 
 
+void LCodeGen::DoCheckMapCommon(Register reg,
+                                Register scratch,
+                                Handle<Map> map,
+                                CompareMapMode mode,
+                                LEnvironment* env) {
+  Label success;
+  __ CompareMap(reg, scratch, map, &success, mode);
+  DeoptimizeIf(ne, env);
+  __ bind(&success);
+}
+
+
 void LCodeGen::DoCheckMap(LCheckMap* instr) {
   Register scratch = scratch0();
   LOperand* input = instr->InputAt(0);
   ASSERT(input->IsRegister());
   Register reg = ToRegister(input);
-  __ ldr(scratch, FieldMemOperand(reg, HeapObject::kMapOffset));
-  __ cmp(scratch, Operand(instr->hydrogen()->map()));
-  DeoptimizeIf(ne, instr->environment());
+  Handle<Map> map = instr->hydrogen()->map();
+  DoCheckMapCommon(reg, scratch, map, instr->hydrogen()->mode(),
+                   instr->environment());
 }
 
 
@@ -4231,9 +4243,9 @@ void LCodeGen::DoCheckPrototypeMaps(LCheckPrototypeMaps* instr) {
 
   // Check prototype maps up to the holder.
   while (!current_prototype.is_identical_to(holder)) {
-    __ ldr(temp2, FieldMemOperand(temp1, HeapObject::kMapOffset));
-    __ cmp(temp2, Operand(Handle<Map>(current_prototype->map())));
-    DeoptimizeIf(ne, instr->environment());
+    DoCheckMapCommon(temp1, temp2,
+                     Handle<Map>(current_prototype->map()),
+                     ALLOW_ELEMENT_TRANSITION_MAPS, instr->environment());
     current_prototype =
         Handle<JSObject>(JSObject::cast(current_prototype->GetPrototype()));
     // Load next prototype object.
@@ -4241,8 +4253,9 @@ void LCodeGen::DoCheckPrototypeMaps(LCheckPrototypeMaps* instr) {
   }
 
   // Check the holder map.
-  __ ldr(temp2, FieldMemOperand(temp1, HeapObject::kMapOffset));
-  __ cmp(temp2, Operand(Handle<Map>(current_prototype->map())));
+  DoCheckMapCommon(temp1, temp2,
+                   Handle<Map>(current_prototype->map()),
+                   ALLOW_ELEMENT_TRANSITION_MAPS, instr->environment());
   DeoptimizeIf(ne, instr->environment());
 }
 

diff --git a/src/arm/lithium-codegen-arm.h b/src/arm/lithium-codegen-arm.h
index e6626481b3affe25813c245b593590f1dfbfca7a..4d6a0c9c0020f65629e3f651baecf219b13f39b3 100644 (file)
--- a/src/arm/lithium-codegen-arm.h
+++ b/src/arm/lithium-codegen-arm.h
@@ -1,4 +1,4 @@
-// Copyright 2011 the V8 project authors. All rights reserved.
+// Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
@@ -119,6 +119,9 @@ class LCodeGen BASE_EMBEDDED {
   void DoDeferredInstanceOfKnownGlobal(LInstanceOfKnownGlobal* instr,
                                        Label* map_check);
 
+  void DoCheckMapCommon(Register reg, Register scratch, Handle<Map> map,
+                        CompareMapMode mode, LEnvironment* env);
+
   // Parallel move support.
   void DoParallelMove(LParallelMove* move);
   void DoGap(LGap* instr);

diff --git a/src/arm/macro-assembler-arm.cc b/src/arm/macro-assembler-arm.cc
index 59a5e5ba79efc38b5fbbfbf4c9e76a25d4cdc2f6..ca3771fc9e5333ba348803a54e2dd1db03821f30 100644 (file)
--- a/src/arm/macro-assembler-arm.cc
+++ b/src/arm/macro-assembler-arm.cc
@@ -1,4 +1,4 @@
-// Copyright 2011 the V8 project authors. All rights reserved.
+// Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
@@ -1992,18 +1992,50 @@ void MacroAssembler::StoreNumberToDoubleElements(Register value_reg,
 }
 
 
+void MacroAssembler::CompareMap(Register obj,
+                                Register scratch,
+                                Handle<Map> map,
+                                Label* early_success,
+                                CompareMapMode mode) {
+  ldr(scratch, FieldMemOperand(obj, HeapObject::kMapOffset));
+  cmp(scratch, Operand(map));
+  if (mode == ALLOW_ELEMENT_TRANSITION_MAPS) {
+    bool ignore;
+    Map* transitioned_fast_element_map(
+        map->LookupElementsTransitionMap(FAST_ELEMENTS, &ignore));
+    ASSERT(transitioned_fast_element_map == NULL ||
+           map->elements_kind() != FAST_ELEMENTS);
+    if (transitioned_fast_element_map != NULL) {
+      b(eq, early_success);
+      cmp(scratch, Operand(Handle<Map>(transitioned_fast_element_map)));
+    }
+
+    Map* transitioned_double_map(
+        map->LookupElementsTransitionMap(FAST_DOUBLE_ELEMENTS, &ignore));
+    ASSERT(transitioned_double_map == NULL ||
+           map->elements_kind() == FAST_SMI_ONLY_ELEMENTS);
+    if (transitioned_double_map != NULL) {
+      b(eq, early_success);
+      cmp(scratch, Operand(Handle<Map>(transitioned_double_map)));
+    }
+  }
+}
+
+
 void MacroAssembler::CheckMap(Register obj,
                               Register scratch,
                               Handle<Map> map,
                               Label* fail,
-                              SmiCheckType smi_check_type) {
+                              SmiCheckType smi_check_type,
+                              CompareMapMode mode) {
   if (smi_check_type == DO_SMI_CHECK) {
     JumpIfSmi(obj, fail);
   }
-  ldr(scratch, FieldMemOperand(obj, HeapObject::kMapOffset));
-  mov(ip, Operand(map));
-  cmp(scratch, ip);
+
+  Label success;
+  CompareMap(obj, scratch, map, &success, mode);
   b(ne, fail);
+  bind(&success);
 }
 
 

diff --git a/src/arm/macro-assembler-arm.h b/src/arm/macro-assembler-arm.h
index 392c2f7503fee193086b73ed2986e158c1772985..20db22f46f0f4ac540eee55bbee004e8f9ee38a0 100644 (file)
--- a/src/arm/macro-assembler-arm.h
+++ b/src/arm/macro-assembler-arm.h
@@ -1,4 +1,4 @@
-// Copyright 2011 the V8 project authors. All rights reserved.
+// Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
@@ -790,15 +790,26 @@ class MacroAssembler: public Assembler {
                                    Register scratch4,
                                    Label* fail);
 
-  // Check if the map of an object is equal to a specified map (either
-  // given directly or as an index into the root list) and branch to
-  // label if not. Skip the smi check if not required (object is known
-  // to be a heap object)
+  // Compare an object's map with the specified map and its transitioned
+  // elements maps if mode is ALLOW_ELEMENT_TRANSITION_MAPS. Condition flags are
+  // set with result of map compare. If multiple map compares are required, the
+  // compare sequences branches to early_success.
+  void CompareMap(Register obj,
+                  Register scratch,
+                  Handle<Map> map,
+                  Label* early_success,
+                  CompareMapMode mode = REQUIRE_EXACT_MAP);
+
+  // Check if the map of an object is equal to a specified map and branch to
+  // label if not. Skip the smi check if not required (object is known to be a
+  // heap object). If mode is ALLOW_ELEMENT_TRANSITION_MAPS, then also match
+  // against maps that are ElementsKind transition maps of the specificed map.
   void CheckMap(Register obj,
                 Register scratch,
                 Handle<Map> map,
                 Label* fail,
-                SmiCheckType smi_check_type);
+                SmiCheckType smi_check_type,
+                CompareMapMode mode = REQUIRE_EXACT_MAP);
 
 
   void CheckMap(Register obj,

diff --git a/src/arm/stub-cache-arm.cc b/src/arm/stub-cache-arm.cc
index b6b2ee2f0493e0d441a49c0c757901d27899e35f..8947550eb24c8f7ae0c25d02f4365174bad244cf 100644 (file)
--- a/src/arm/stub-cache-arm.cc
+++ b/src/arm/stub-cache-arm.cc
@@ -1,4 +1,4 @@
-// Copyright 2011 the V8 project authors. All rights reserved.
+// Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
@@ -1019,10 +1019,9 @@ Register StubCompiler::CheckPrototypes(Handle<JSObject> object,
       __ ldr(reg, FieldMemOperand(scratch1, Map::kPrototypeOffset));
     } else {
       Handle<Map> current_map(current->map());
-      __ ldr(scratch1, FieldMemOperand(reg, HeapObject::kMapOffset));
-      __ cmp(scratch1, Operand(current_map));
-      // Branch on the result of the map check.
-      __ b(ne, miss);
+      __ CheckMap(reg, scratch1, current_map, miss, DONT_DO_SMI_CHECK,
+                  ALLOW_ELEMENT_TRANSITION_MAPS);
+
       // Check access rights to the global object.  This has to happen after
       // the map check so that we know that the object is actually a global
       // object.
@@ -1053,9 +1052,8 @@ Register StubCompiler::CheckPrototypes(Handle<JSObject> object,
   LOG(masm()->isolate(), IntEvent("check-maps-depth", depth + 1));
 
   // Check the holder map.
-  __ ldr(scratch1, FieldMemOperand(reg, HeapObject::kMapOffset));
-  __ cmp(scratch1, Operand(Handle<Map>(current->map())));
-  __ b(ne, miss);
+  __ CheckMap(reg, scratch1, Handle<Map>(current->map()), miss,
+              DONT_DO_SMI_CHECK, ALLOW_ELEMENT_TRANSITION_MAPS);
 
   // Perform security check for access to the global object.
   ASSERT(holder->IsJSGlobalProxy() || !holder->IsAccessCheckNeeded());

diff --git a/src/hydrogen-instructions.h b/src/hydrogen-instructions.h
index 1856c80929676e0d363d0f6ebe44a37faa3f44a4..0141751465ab9d46eea432e706943a5caa2add04 100644 (file)
--- a/src/hydrogen-instructions.h
+++ b/src/hydrogen-instructions.h
@@ -1,4 +1,4 @@
-// Copyright 2011 the V8 project authors. All rights reserved.
+// Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
@@ -1921,8 +1921,11 @@ class HLoadExternalArrayPointer: public HUnaryOperation {
 
 class HCheckMap: public HTemplateInstruction<2> {
  public:
-  HCheckMap(HValue* value, Handle<Map> map, HValue* typecheck = NULL)
-      : map_(map) {
+  HCheckMap(HValue* value, Handle<Map> map,
+            HValue* typecheck = NULL,
+            CompareMapMode mode = REQUIRE_EXACT_MAP)
+      : map_(map),
+        mode_(mode) {
     SetOperandAt(0, value);
     // If callers don't depend on a typecheck, they can pass in NULL. In that
     // case we use a copy of the |value| argument as a dummy value.
@@ -1940,17 +1943,24 @@ class HCheckMap: public HTemplateInstruction<2> {
 
   HValue* value() { return OperandAt(0); }
   Handle<Map> map() const { return map_; }
+  CompareMapMode mode() const { return mode_; }
 
   DECLARE_CONCRETE_INSTRUCTION(CheckMap)
 
  protected:
   virtual bool DataEquals(HValue* other) {
     HCheckMap* b = HCheckMap::cast(other);
-    return map_.is_identical_to(b->map());
+    // Two CheckMaps instructions are DataEqual if their maps are identical and
+    // they have the same mode. If the map to check has FAST_ELEMENTS, then the
+    // mode doesn't have to match: since there are no transitioned maps to
+    // compare the generated code will be equivalent regardless of mode.
+    return map_.is_identical_to(b->map()) &&
+        (b->mode() == mode() || map_->elements_kind() == FAST_ELEMENTS);
   }
 
  private:
   Handle<Map> map_;
+  CompareMapMode mode_;
 };
 
 

diff --git a/src/hydrogen.cc b/src/hydrogen.cc
index 92308704328c7968176fbbe88fd392b58622207d..cd029748419031757471afb083b62052113313e6 100644 (file)
--- a/src/hydrogen.cc
+++ b/src/hydrogen.cc
@@ -1,4 +1,4 @@
-// Copyright 2011 the V8 project authors. All rights reserved.
+// Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
@@ -4652,7 +4652,8 @@ void HGraphBuilder::AddCheckConstantFunction(Call* expr,
   // its prototypes.
   if (smi_and_map_check) {
     AddInstruction(new(zone()) HCheckNonSmi(receiver));
-    AddInstruction(new(zone()) HCheckMap(receiver, receiver_map));
+    AddInstruction(new(zone()) HCheckMap(receiver, receiver_map,
+                                         NULL, ALLOW_ELEMENT_TRANSITION_MAPS));
   }
   if (!expr->holder().is_null()) {
     AddInstruction(new(zone()) HCheckPrototypeMaps(

diff --git a/src/ia32/lithium-codegen-ia32.cc b/src/ia32/lithium-codegen-ia32.cc
index 137d62c554648a367a14cf67e69f1d404389017e..edde934b4e15a5a22de3c779e1f48e417e0d9521 100644 (file)
--- a/src/ia32/lithium-codegen-ia32.cc
+++ b/src/ia32/lithium-codegen-ia32.cc
@@ -1,4 +1,4 @@
-// Copyright 2011 the V8 project authors. All rights reserved.
+// Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
@@ -4033,13 +4033,23 @@ void LCodeGen::DoCheckFunction(LCheckFunction* instr) {
 }
 
 
+void LCodeGen::DoCheckMapCommon(Register reg,
+                                Handle<Map> map,
+                                CompareMapMode mode,
+                                LEnvironment* env) {
+  Label success;
+  __ CompareMap(reg, map, &success, mode);
+  DeoptimizeIf(not_equal, env);
+  __ bind(&success);
+}
+
+
 void LCodeGen::DoCheckMap(LCheckMap* instr) {
   LOperand* input = instr->InputAt(0);
   ASSERT(input->IsRegister());
   Register reg = ToRegister(input);
-  __ cmp(FieldOperand(reg, HeapObject::kMapOffset),
-         instr->hydrogen()->map());
-  DeoptimizeIf(not_equal, instr->environment());
+  Handle<Map> map = instr->hydrogen()->map();
+  DoCheckMapCommon(reg, map, instr->hydrogen()->mode(), instr->environment());
 }
 
 
@@ -4102,9 +4112,9 @@ void LCodeGen::DoCheckPrototypeMaps(LCheckPrototypeMaps* instr) {
 
   // Check prototype maps up to the holder.
   while (!current_prototype.is_identical_to(holder)) {
-    __ cmp(FieldOperand(reg, HeapObject::kMapOffset),
-           Handle<Map>(current_prototype->map()));
-    DeoptimizeIf(not_equal, instr->environment());
+    DoCheckMapCommon(reg, Handle<Map>(current_prototype->map()),
+                     ALLOW_ELEMENT_TRANSITION_MAPS, instr->environment());
+
     current_prototype =
         Handle<JSObject>(JSObject::cast(current_prototype->GetPrototype()));
     // Load next prototype object.
@@ -4112,9 +4122,8 @@ void LCodeGen::DoCheckPrototypeMaps(LCheckPrototypeMaps* instr) {
   }
 
   // Check the holder map.
-  __ cmp(FieldOperand(reg, HeapObject::kMapOffset),
-         Handle<Map>(current_prototype->map()));
-  DeoptimizeIf(not_equal, instr->environment());
+  DoCheckMapCommon(reg, Handle<Map>(current_prototype->map()),
+                   ALLOW_ELEMENT_TRANSITION_MAPS, instr->environment());
 }
 
 

diff --git a/src/ia32/lithium-codegen-ia32.h b/src/ia32/lithium-codegen-ia32.h
index 375f137d7bbe3d1b345bac402b873cf898feb94f..38d0b3bce25fbe8178172b8859705852cf08d722 100644 (file)
--- a/src/ia32/lithium-codegen-ia32.h
+++ b/src/ia32/lithium-codegen-ia32.h
@@ -1,4 +1,4 @@
-// Copyright 2011 the V8 project authors. All rights reserved.
+// Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
@@ -110,6 +110,9 @@ class LCodeGen BASE_EMBEDDED {
   void DoDeferredInstanceOfKnownGlobal(LInstanceOfKnownGlobal* instr,
                                        Label* map_check);
 
+  void DoCheckMapCommon(Register reg, Handle<Map> map,
+                        CompareMapMode mode, LEnvironment* env);
+
   // Parallel move support.
   void DoParallelMove(LParallelMove* move);
   void DoGap(LGap* instr);

diff --git a/src/ia32/macro-assembler-ia32.cc b/src/ia32/macro-assembler-ia32.cc
index 3356e818922d0ccce2967e4cd2bf6a586917663d..ace1bed569a1550140084519668a825f9d03267d 100644 (file)
--- a/src/ia32/macro-assembler-ia32.cc
+++ b/src/ia32/macro-assembler-ia32.cc
@@ -1,4 +1,4 @@
-// Copyright 2011 the V8 project authors. All rights reserved.
+// Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
@@ -487,15 +487,49 @@ void MacroAssembler::StoreNumberToDoubleElements(
 }
 
 
+void MacroAssembler::CompareMap(Register obj,
+                                Handle<Map> map,
+                                Label* early_success,
+                                CompareMapMode mode) {
+  cmp(FieldOperand(obj, HeapObject::kMapOffset), map);
+  if (mode == ALLOW_ELEMENT_TRANSITION_MAPS) {
+    bool ignore;
+    Map* transitioned_fast_element_map(
+        map->LookupElementsTransitionMap(FAST_ELEMENTS, &ignore));
+    ASSERT(transitioned_fast_element_map == NULL ||
+           map->elements_kind() != FAST_ELEMENTS);
+    if (transitioned_fast_element_map != NULL) {
+      j(equal, early_success, Label::kNear);
+      cmp(FieldOperand(obj, HeapObject::kMapOffset),
+          Handle<Map>(transitioned_fast_element_map));
+    }
+
+    Map* transitioned_double_map(
+        map->LookupElementsTransitionMap(FAST_DOUBLE_ELEMENTS, &ignore));
+    ASSERT(transitioned_double_map == NULL ||
+           map->elements_kind() == FAST_SMI_ONLY_ELEMENTS);
+    if (transitioned_double_map != NULL) {
+      j(equal, early_success, Label::kNear);
+      cmp(FieldOperand(obj, HeapObject::kMapOffset),
+          Handle<Map>(transitioned_double_map));
+    }
+  }
+}
+
+
 void MacroAssembler::CheckMap(Register obj,
                               Handle<Map> map,
                               Label* fail,
-                              SmiCheckType smi_check_type) {
+                              SmiCheckType smi_check_type,
+                              CompareMapMode mode) {
   if (smi_check_type == DO_SMI_CHECK) {
     JumpIfSmi(obj, fail);
   }
-  cmp(FieldOperand(obj, HeapObject::kMapOffset), Immediate(map));
+
+  Label success;
+  CompareMap(obj, map, &success, mode);
   j(not_equal, fail);
+  bind(&success);
 }
 
 

diff --git a/src/ia32/macro-assembler-ia32.h b/src/ia32/macro-assembler-ia32.h
index e6a17417d832e41f65167a178e438ca954b40404..f7400ad390cc50c03b4a7c64b0b105586a39968a 100644 (file)
--- a/src/ia32/macro-assembler-ia32.h
+++ b/src/ia32/macro-assembler-ia32.h
@@ -1,4 +1,4 @@
-// Copyright 2011 the V8 project authors. All rights reserved.
+// Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
@@ -356,13 +356,24 @@ class MacroAssembler: public Assembler {
                                    Label* fail,
                                    bool specialize_for_processor);
 
+  // Compare an object's map with the specified map and its transitioned
+  // elements maps if mode is ALLOW_ELEMENT_TRANSITION_MAPS. FLAGS are set with
+  // result of map compare. If multiple map compares are required, the compare
+  // sequences branches to early_success.
+  void CompareMap(Register obj,
+                  Handle<Map> map,
+                  Label* early_success,
+                  CompareMapMode mode = REQUIRE_EXACT_MAP);
+
   // Check if the map of an object is equal to a specified map and branch to
   // label if not. Skip the smi check if not required (object is known to be a
-  // heap object)
+  // heap object). If mode is ALLOW_ELEMENT_TRANSITION_MAPS, then also match
+  // against maps that are ElementsKind transition maps of the specificed map.
   void CheckMap(Register obj,
                 Handle<Map> map,
                 Label* fail,
-                SmiCheckType smi_check_type);
+                SmiCheckType smi_check_type,
+                CompareMapMode mode = REQUIRE_EXACT_MAP);
 
   // Check if the map of an object is equal to a specified map and branch to a
   // specified target if equal. Skip the smi check if not required (object is

diff --git a/src/ia32/stub-cache-ia32.cc b/src/ia32/stub-cache-ia32.cc
index c27a60fd06573ae7fc91c30fd343886f3772d453..051a8177eac0f10bf168ed6324f50c5947766df4 100644 (file)
--- a/src/ia32/stub-cache-ia32.cc
+++ b/src/ia32/stub-cache-ia32.cc
@@ -878,13 +878,10 @@ Register StubCompiler::CheckPrototypes(Handle<JSObject> object,
       if (in_new_space) {
         // Save the map in scratch1 for later.
         __ mov(scratch1, FieldOperand(reg, HeapObject::kMapOffset));
-        __ cmp(scratch1, Immediate(current_map));
-      } else {
-        __ cmp(FieldOperand(reg, HeapObject::kMapOffset),
-               Immediate(current_map));
       }
-      // Branch on the result of the map check.
-      __ j(not_equal, miss);
+      __ CheckMap(reg, current_map, miss, DONT_DO_SMI_CHECK,
+                  ALLOW_ELEMENT_TRANSITION_MAPS);
+
       // Check access rights to the global object.  This has to happen after
       // the map check so that we know that the object is actually a global
       // object.
@@ -916,9 +913,8 @@ Register StubCompiler::CheckPrototypes(Handle<JSObject> object,
   LOG(isolate(), IntEvent("check-maps-depth", depth + 1));
 
   // Check the holder map.
-  __ cmp(FieldOperand(reg, HeapObject::kMapOffset),
-         Immediate(Handle<Map>(holder->map())));
-  __ j(not_equal, miss);
+  __ CheckMap(reg, Handle<Map>(holder->map()),
+              miss, DONT_DO_SMI_CHECK, ALLOW_ELEMENT_TRANSITION_MAPS);
 
   // Perform security check for access to the global object.
   ASSERT(holder->IsJSGlobalProxy() || !holder->IsAccessCheckNeeded());

diff --git a/src/lithium.h b/src/lithium.h
index b605eb97bd3a81565d4f084c74acb99c6573641b..48a533c57ef79b3c316df1c6ba51a21aa9f38249 100644 (file)
--- a/src/lithium.h
+++ b/src/lithium.h
@@ -1,4 +1,4 @@
-// Copyright 2011 the V8 project authors. All rights reserved.
+// Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
@@ -523,8 +523,6 @@ class LEnvironment: public ZoneObject {
   LOperand** spilled_double_registers_;
 
   LEnvironment* outer_;
-
-  friend class LCodegen;
 };
 
 

diff --git a/src/objects.h b/src/objects.h
index 5aaadcc3e47f9a407b1fbbfb09c35b725737d610..906afa13b5b0ca4b1970884d2b7ea44210e4dd5d 100644 (file)
--- a/src/objects.h
+++ b/src/objects.h
@@ -1,4 +1,4 @@
-// Copyright 2011 the V8 project authors. All rights reserved.
+// Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
@@ -162,6 +162,11 @@ enum ElementsKind {
   LAST_ELEMENTS_KIND = EXTERNAL_PIXEL_ELEMENTS
 };
 
+enum CompareMapMode {
+  REQUIRE_EXACT_MAP,
+  ALLOW_ELEMENT_TRANSITION_MAPS
+};
+
 const int kElementsKindCount = LAST_ELEMENTS_KIND - FIRST_ELEMENTS_KIND + 1;
 
 void PrintElementsKind(FILE* out, ElementsKind kind);

diff --git a/src/x64/lithium-codegen-x64.cc b/src/x64/lithium-codegen-x64.cc
index 6239acb51531d1f39ecfd1e247315736e82c3e29..bafe74eec5e52c2c9bc3566963e354da497dd531 100644 (file)
--- a/src/x64/lithium-codegen-x64.cc
+++ b/src/x64/lithium-codegen-x64.cc
@@ -1,4 +1,4 @@
-// Copyright 2011 the V8 project authors. All rights reserved.
+// Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
@@ -3747,13 +3747,23 @@ void LCodeGen::DoCheckFunction(LCheckFunction* instr) {
 }
 
 
+void LCodeGen::DoCheckMapCommon(Register reg,
+                                Handle<Map> map,
+                                CompareMapMode mode,
+                                LEnvironment* env) {
+  Label success;
+  __ CompareMap(reg, map, &success, mode);
+  DeoptimizeIf(not_equal, env);
+  __ bind(&success);
+}
+
+
 void LCodeGen::DoCheckMap(LCheckMap* instr) {
   LOperand* input = instr->InputAt(0);
   ASSERT(input->IsRegister());
   Register reg = ToRegister(input);
-  __ Cmp(FieldOperand(reg, HeapObject::kMapOffset),
-         instr->hydrogen()->map());
-  DeoptimizeIf(not_equal, instr->environment());
+  Handle<Map> map = instr->hydrogen()->map();
+  DoCheckMapCommon(reg, map, instr->hydrogen()->mode(), instr->environment());
 }
 
 
@@ -3819,9 +3829,8 @@ void LCodeGen::DoCheckPrototypeMaps(LCheckPrototypeMaps* instr) {
 
   // Check prototype maps up to the holder.
   while (!current_prototype.is_identical_to(holder)) {
-    __ Cmp(FieldOperand(reg, HeapObject::kMapOffset),
-           Handle<Map>(current_prototype->map()));
-    DeoptimizeIf(not_equal, instr->environment());
+    DoCheckMapCommon(reg, Handle<Map>(current_prototype->map()),
+                     ALLOW_ELEMENT_TRANSITION_MAPS, instr->environment());
     current_prototype =
         Handle<JSObject>(JSObject::cast(current_prototype->GetPrototype()));
     // Load next prototype object.
@@ -3829,9 +3838,8 @@ void LCodeGen::DoCheckPrototypeMaps(LCheckPrototypeMaps* instr) {
   }
 
   // Check the holder map.
-  __ Cmp(FieldOperand(reg, HeapObject::kMapOffset),
-         Handle<Map>(current_prototype->map()));
-  DeoptimizeIf(not_equal, instr->environment());
+    DoCheckMapCommon(reg, Handle<Map>(current_prototype->map()),
+                     ALLOW_ELEMENT_TRANSITION_MAPS, instr->environment());
 }
 
 

diff --git a/src/x64/lithium-codegen-x64.h b/src/x64/lithium-codegen-x64.h
index 832942f1efcc50b7dbe4d8db315bf7ac4a2437a4..5cffb5a68ac3d57f5937f9338b0121bee7432b64 100644 (file)
--- a/src/x64/lithium-codegen-x64.h
+++ b/src/x64/lithium-codegen-x64.h
@@ -1,4 +1,4 @@
-// Copyright 2011 the V8 project authors. All rights reserved.
+// Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
@@ -102,7 +102,10 @@ class LCodeGen BASE_EMBEDDED {
   void DoDeferredInstanceOfKnownGlobal(LInstanceOfKnownGlobal* instr,
                                        Label* map_check);
 
-  // Parallel move support.
+  void DoCheckMapCommon(Register reg, Handle<Map> map,
+                        CompareMapMode mode, LEnvironment* env);
+
+// Parallel move support.
   void DoParallelMove(LParallelMove* move);
   void DoGap(LGap* instr);
 

diff --git a/src/x64/macro-assembler-x64.cc b/src/x64/macro-assembler-x64.cc
index 10e423b5b9537f9b7841f2aa2f17c5eccc8b7cec..e139df75bb2df4d47ac259ddbbf1b0f658ae4e8f 100644 (file)
--- a/src/x64/macro-assembler-x64.cc
+++ b/src/x64/macro-assembler-x64.cc
@@ -1,4 +1,4 @@
-// Copyright 2011 the V8 project authors. All rights reserved.
+// Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
@@ -2739,15 +2739,49 @@ void MacroAssembler::StoreNumberToDoubleElements(
 }
 
 
+void MacroAssembler::CompareMap(Register obj,
+                                Handle<Map> map,
+                                Label* early_success,
+                                CompareMapMode mode) {
+  Cmp(FieldOperand(obj, HeapObject::kMapOffset), map);
+  if (mode == ALLOW_ELEMENT_TRANSITION_MAPS) {
+    bool ignore;
+    Map* transitioned_fast_element_map(
+        map->LookupElementsTransitionMap(FAST_ELEMENTS, &ignore));
+    ASSERT(transitioned_fast_element_map == NULL ||
+           map->elements_kind() != FAST_ELEMENTS);
+    if (transitioned_fast_element_map != NULL) {
+      j(equal, early_success, Label::kNear);
+      Cmp(FieldOperand(obj, HeapObject::kMapOffset),
+          Handle<Map>(transitioned_fast_element_map));
+    }
+
+    Map* transitioned_double_map(
+        map->LookupElementsTransitionMap(FAST_DOUBLE_ELEMENTS, &ignore));
+    ASSERT(transitioned_double_map == NULL ||
+           map->elements_kind() == FAST_SMI_ONLY_ELEMENTS);
+    if (transitioned_double_map != NULL) {
+      j(equal, early_success, Label::kNear);
+      Cmp(FieldOperand(obj, HeapObject::kMapOffset),
+          Handle<Map>(transitioned_double_map));
+    }
+  }
+}
+
+
 void MacroAssembler::CheckMap(Register obj,
                               Handle<Map> map,
                               Label* fail,
-                              SmiCheckType smi_check_type) {
+                              SmiCheckType smi_check_type,
+                              CompareMapMode mode) {
   if (smi_check_type == DO_SMI_CHECK) {
     JumpIfSmi(obj, fail);
   }
-  Cmp(FieldOperand(obj, HeapObject::kMapOffset), map);
+
+  Label success;
+  CompareMap(obj, map, &success, mode);
   j(not_equal, fail);
+  bind(&success);
 }
 
 

diff --git a/src/x64/macro-assembler-x64.h b/src/x64/macro-assembler-x64.h
index 97a98017c5897e6bedb38d6d54ac751acf04bd89..82f8f6df77677c5735bf614e64cd27473e9fd9bd 100644 (file)
--- a/src/x64/macro-assembler-x64.h
+++ b/src/x64/macro-assembler-x64.h
@@ -1,4 +1,4 @@
-// Copyright 2011 the V8 project authors. All rights reserved.
+// Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
@@ -889,13 +889,24 @@ class MacroAssembler: public Assembler {
                                    XMMRegister xmm_scratch,
                                    Label* fail);
 
-  // Check if the map of an object is equal to a specified map and
-  // branch to label if not. Skip the smi check if not required
-  // (object is known to be a heap object)
+  // Compare an object's map with the specified map and its transitioned
+  // elements maps if mode is ALLOW_ELEMENT_TRANSITION_MAPS. FLAGS are set with
+  // result of map compare. If multiple map compares are required, the compare
+  // sequences branches to early_success.
+  void CompareMap(Register obj,
+                  Handle<Map> map,
+                  Label* early_success,
+                  CompareMapMode mode = REQUIRE_EXACT_MAP);
+
+  // Check if the map of an object is equal to a specified map and branch to
+  // label if not. Skip the smi check if not required (object is known to be a
+  // heap object). If mode is ALLOW_ELEMENT_TRANSITION_MAPS, then also match
+  // against maps that are ElementsKind transition maps of the specificed map.
   void CheckMap(Register obj,
                 Handle<Map> map,
                 Label* fail,
-                SmiCheckType smi_check_type);
+                SmiCheckType smi_check_type,
+                CompareMapMode mode = REQUIRE_EXACT_MAP);
 
   // Check if the map of an object is equal to a specified map and branch to a
   // specified target if equal. Skip the smi check if not required (object is

diff --git a/src/x64/stub-cache-x64.cc b/src/x64/stub-cache-x64.cc
index a28dbbf0272144f9db8f630a23d5c567be77b295..8830bc14a7dea0a62347dd8dc054ed8b6376bad1 100644 (file)
--- a/src/x64/stub-cache-x64.cc
+++ b/src/x64/stub-cache-x64.cc
@@ -1,4 +1,4 @@
-// Copyright 2011 the V8 project authors. All rights reserved.
+// Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
@@ -864,12 +864,10 @@ Register StubCompiler::CheckPrototypes(Handle<JSObject> object,
       if (in_new_space) {
         // Save the map in scratch1 for later.
         __ movq(scratch1, FieldOperand(reg, HeapObject::kMapOffset));
-        __ Cmp(scratch1, current_map);
-      } else {
-        __ Cmp(FieldOperand(reg, HeapObject::kMapOffset), current_map);
       }
-      // Branch on the result of the map check.
-      __ j(not_equal, miss);
+      __ CheckMap(reg, Handle<Map>(current_map),
+                  miss, DONT_DO_SMI_CHECK, ALLOW_ELEMENT_TRANSITION_MAPS);
+
       // Check access rights to the global object.  This has to happen after
       // the map check so that we know that the object is actually a global
       // object.
@@ -901,8 +899,8 @@ Register StubCompiler::CheckPrototypes(Handle<JSObject> object,
   LOG(isolate(), IntEvent("check-maps-depth", depth + 1));
 
   // Check the holder map.
-  __ Cmp(FieldOperand(reg, HeapObject::kMapOffset), Handle<Map>(holder->map()));
-  __ j(not_equal, miss);
+  __ CheckMap(reg, Handle<Map>(holder->map()),
+              miss, DONT_DO_SMI_CHECK, ALLOW_ELEMENT_TRANSITION_MAPS);
 
   // Perform security check for access to the global object.
   ASSERT(current->IsJSGlobalProxy() || !current->IsAccessCheckNeeded());