Make TestJSArrayForAllocationMemento less awkward.

Generated code ended up having two conditional jump statements in a
row. Also introduce JumpIfJSArrayHasAllocationMemento which handles
most cases more simply.

R=jkummerow@chromium.org

Review URL: https://codereview.chromium.org/26841009

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@17220 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/arm/codegen-arm.cc

@@ -402,8 +402,7 @@ void ElementsTransitionGenerator::GenerateMapChangeElementsTransition(
   // -----------------------------------
   if (mode == TRACK_ALLOCATION_SITE) {
     ASSERT(allocation_memento_found != NULL);
-    __ TestJSArrayForAllocationMemento(r2, r4);
-    __ b(eq, allocation_memento_found);
+    __ JumpIfJSArrayHasAllocationMemento(r2, r4, allocation_memento_found);
   }
 
   // Set transitioned map.
@@ -432,8 +431,7 @@ void ElementsTransitionGenerator::GenerateSmiToDouble(
   Label loop, entry, convert_hole, gc_required, only_change_map, done;
 
   if (mode == TRACK_ALLOCATION_SITE) {
-    __ TestJSArrayForAllocationMemento(r2, r4);
-    __ b(eq, fail);
+    __ JumpIfJSArrayHasAllocationMemento(r2, r4, fail);
   }
 
   // Check for empty arrays, which only require a map transition and no changes
@@ -559,8 +557,7 @@ void ElementsTransitionGenerator::GenerateDoubleToObject(
   Label entry, loop, convert_hole, gc_required, only_change_map;
 
   if (mode == TRACK_ALLOCATION_SITE) {
-    __ TestJSArrayForAllocationMemento(r2, r4);
-    __ b(eq, fail);
+    __ JumpIfJSArrayHasAllocationMemento(r2, r4, fail);
   }
 
   // Check for empty arrays, which only require a map transition and no changes

src/arm/lithium-codegen-arm.cc

@@ -4536,8 +4536,10 @@ void LCodeGen::DoTransitionElementsKind(LTransitionElementsKind* instr) {
 void LCodeGen::DoTrapAllocationMemento(LTrapAllocationMemento* instr) {
   Register object = ToRegister(instr->object());
   Register temp = ToRegister(instr->temp());
-  __ TestJSArrayForAllocationMemento(object, temp);
+  Label no_memento_found;
+  __ TestJSArrayForAllocationMemento(object, temp, &no_memento_found);
   DeoptimizeIf(eq, instr->environment());
+  __ bind(&no_memento_found);
 }
 
 

src/arm/macro-assembler-arm.cc

@@ -3858,8 +3858,8 @@ void MacroAssembler::CheckEnumCache(Register null_value, Label* call_runtime) {
 
 void MacroAssembler::TestJSArrayForAllocationMemento(
     Register receiver_reg,
-    Register scratch_reg) {
-  Label no_memento_available;
+    Register scratch_reg,
+    Label* no_memento_found) {
   ExternalReference new_space_start =
       ExternalReference::new_space_start(isolate());
   ExternalReference new_space_allocation_top =
@@ -3867,15 +3867,14 @@ void MacroAssembler::TestJSArrayForAllocationMemento(
   add(scratch_reg, receiver_reg,
       Operand(JSArray::kSize + AllocationMemento::kSize - kHeapObjectTag));
   cmp(scratch_reg, Operand(new_space_start));
-  b(lt, &no_memento_available);
+  b(lt, no_memento_found);
   mov(ip, Operand(new_space_allocation_top));
   ldr(ip, MemOperand(ip));
   cmp(scratch_reg, ip);
-  b(gt, &no_memento_available);
+  b(gt, no_memento_found);
   ldr(scratch_reg, MemOperand(scratch_reg, -AllocationMemento::kSize));
   cmp(scratch_reg,
       Operand(isolate()->factory()->allocation_memento_map()));
-  bind(&no_memento_available);
 }
 
 

src/arm/macro-assembler-arm.h

@@ -1388,9 +1388,20 @@ class MacroAssembler: public Assembler {
   // to another type.
   // On entry, receiver_reg should point to the array object.
   // scratch_reg gets clobbered.
-  // If allocation info is present, condition flags are set to eq
+  // If allocation info is present, condition flags are set to eq.
   void TestJSArrayForAllocationMemento(Register receiver_reg,
-                                       Register scratch_reg);
+                                       Register scratch_reg,
+                                       Label* no_memento_found);
+
+  void JumpIfJSArrayHasAllocationMemento(Register receiver_reg,
+                                         Register scratch_reg,
+                                         Label* memento_found) {
+    Label no_memento_found;
+    TestJSArrayForAllocationMemento(receiver_reg, scratch_reg,
+                                    &no_memento_found);
+    b(eq, memento_found);
+    bind(&no_memento_found);
+  }
 
  private:
   void CallCFunctionHelper(Register function,

src/ia32/codegen-ia32.cc

@@ -666,8 +666,7 @@ void ElementsTransitionGenerator::GenerateMapChangeElementsTransition(
   // -----------------------------------
   if (mode == TRACK_ALLOCATION_SITE) {
     ASSERT(allocation_memento_found != NULL);
-    __ TestJSArrayForAllocationMemento(edx, edi);
-    __ j(equal, allocation_memento_found);
+    __ JumpIfJSArrayHasAllocationMemento(edx, edi, allocation_memento_found);
   }
 
   // Set transitioned map.
@@ -694,8 +693,7 @@ void ElementsTransitionGenerator::GenerateSmiToDouble(
   Label loop, entry, convert_hole, gc_required, only_change_map;
 
   if (mode == TRACK_ALLOCATION_SITE) {
-    __ TestJSArrayForAllocationMemento(edx, edi);
-    __ j(equal, fail);
+    __ JumpIfJSArrayHasAllocationMemento(edx, edi, fail);
   }
 
   // Check for empty arrays, which only require a map transition and no changes
@@ -833,8 +831,7 @@ void ElementsTransitionGenerator::GenerateDoubleToObject(
   Label loop, entry, convert_hole, gc_required, only_change_map, success;
 
   if (mode == TRACK_ALLOCATION_SITE) {
-    __ TestJSArrayForAllocationMemento(edx, edi);
-    __ j(equal, fail);
+    __ JumpIfJSArrayHasAllocationMemento(edx, edi, fail);
   }
 
   // Check for empty arrays, which only require a map transition and no changes

src/ia32/lithium-codegen-ia32.cc

@@ -4813,8 +4813,10 @@ void LCodeGen::DoStoreKeyedGeneric(LStoreKeyedGeneric* instr) {
 void LCodeGen::DoTrapAllocationMemento(LTrapAllocationMemento* instr) {
   Register object = ToRegister(instr->object());
   Register temp = ToRegister(instr->temp());
-  __ TestJSArrayForAllocationMemento(object, temp);
+  Label no_memento_found;
+  __ TestJSArrayForAllocationMemento(object, temp, &no_memento_found);
   DeoptimizeIf(equal, instr->environment());
+  __ bind(&no_memento_found);
 }
 
 

src/ia32/macro-assembler-ia32.cc

@@ -3512,9 +3512,8 @@ void MacroAssembler::CheckEnumCache(Label* call_runtime) {
 
 void MacroAssembler::TestJSArrayForAllocationMemento(
     Register receiver_reg,
-    Register scratch_reg) {
-  Label no_memento_available;
-
+    Register scratch_reg,
+    Label* no_memento_found) {
   ExternalReference new_space_start =
       ExternalReference::new_space_start(isolate());
   ExternalReference new_space_allocation_top =
@@ -3523,12 +3522,11 @@ void MacroAssembler::TestJSArrayForAllocationMemento(
   lea(scratch_reg, Operand(receiver_reg,
       JSArray::kSize + AllocationMemento::kSize - kHeapObjectTag));
   cmp(scratch_reg, Immediate(new_space_start));
-  j(less, &no_memento_available);
+  j(less, no_memento_found);
   cmp(scratch_reg, Operand::StaticVariable(new_space_allocation_top));
-  j(greater, &no_memento_available);
+  j(greater, no_memento_found);
   cmp(MemOperand(scratch_reg, -AllocationMemento::kSize),
       Immediate(isolate()->factory()->allocation_memento_map()));
-  bind(&no_memento_available);
 }
 
 

src/ia32/macro-assembler-ia32.h

@@ -957,9 +957,20 @@ class MacroAssembler: public Assembler {
   // to another type.
   // On entry, receiver_reg should point to the array object.
   // scratch_reg gets clobbered.
-  // If allocation info is present, conditional code is set to equal
+  // If allocation info is present, conditional code is set to equal.
   void TestJSArrayForAllocationMemento(Register receiver_reg,
-                                       Register scratch_reg);
+                                       Register scratch_reg,
+                                       Label* no_memento_found);
+
+  void JumpIfJSArrayHasAllocationMemento(Register receiver_reg,
+                                         Register scratch_reg,
+                                         Label* memento_found) {
+    Label no_memento_found;
+    TestJSArrayForAllocationMemento(receiver_reg, scratch_reg,
+                                    &no_memento_found);
+    j(equal, memento_found);
+    bind(&no_memento_found);
+  }
 
  private:
   bool generating_stub_;

src/x64/codegen-x64.cc

@@ -263,8 +263,7 @@ void ElementsTransitionGenerator::GenerateMapChangeElementsTransition(
   // -----------------------------------
   if (mode == TRACK_ALLOCATION_SITE) {
     ASSERT(allocation_memento_found != NULL);
-    __ TestJSArrayForAllocationMemento(rdx, rdi);
-    __ j(equal, allocation_memento_found);
+    __ JumpIfJSArrayHasAllocationMemento(rdx, rdi, allocation_memento_found);
   }
 
   // Set transitioned map.
@@ -292,8 +291,7 @@ void ElementsTransitionGenerator::GenerateSmiToDouble(
   Label allocated, new_backing_store, only_change_map, done;
 
   if (mode == TRACK_ALLOCATION_SITE) {
-    __ TestJSArrayForAllocationMemento(rdx, rdi);
-    __ j(equal, fail);
+    __ JumpIfJSArrayHasAllocationMemento(rdx, rdi, fail);
   }
 
   // Check for empty arrays, which only require a map transition and no changes
@@ -418,8 +416,7 @@ void ElementsTransitionGenerator::GenerateDoubleToObject(
   Label loop, entry, convert_hole, gc_required, only_change_map;
 
   if (mode == TRACK_ALLOCATION_SITE) {
-    __ TestJSArrayForAllocationMemento(rdx, rdi);
-    __ j(equal, fail);
+    __ JumpIfJSArrayHasAllocationMemento(rdx, rdi, fail);
   }
 
   // Check for empty arrays, which only require a map transition and no changes

src/x64/lithium-codegen-x64.cc

@@ -4257,8 +4257,10 @@ void LCodeGen::DoTransitionElementsKind(LTransitionElementsKind* instr) {
 void LCodeGen::DoTrapAllocationMemento(LTrapAllocationMemento* instr) {
   Register object = ToRegister(instr->object());
   Register temp = ToRegister(instr->temp());
-  __ TestJSArrayForAllocationMemento(object, temp);
+  Label no_memento_found;
+  __ TestJSArrayForAllocationMemento(object, temp, &no_memento_found);
   DeoptimizeIf(equal, instr->environment());
+  __ bind(&no_memento_found);
 }
 
 

src/x64/macro-assembler-x64.cc

@@ -4921,8 +4921,8 @@ void MacroAssembler::CheckEnumCache(Register null_value, Label* call_runtime) {
 
 void MacroAssembler::TestJSArrayForAllocationMemento(
     Register receiver_reg,
-    Register scratch_reg) {
-  Label no_memento_available;
+    Register scratch_reg,
+    Label* no_memento_found) {
   ExternalReference new_space_start =
       ExternalReference::new_space_start(isolate());
   ExternalReference new_space_allocation_top =
@@ -4932,12 +4932,11 @@ void MacroAssembler::TestJSArrayForAllocationMemento(
       JSArray::kSize + AllocationMemento::kSize - kHeapObjectTag));
   movq(kScratchRegister, new_space_start);
   cmpq(scratch_reg, kScratchRegister);
-  j(less, &no_memento_available);
+  j(less, no_memento_found);
   cmpq(scratch_reg, ExternalOperand(new_space_allocation_top));
-  j(greater, &no_memento_available);
+  j(greater, no_memento_found);
   CompareRoot(MemOperand(scratch_reg, -AllocationMemento::kSize),
               Heap::kAllocationMementoMapRootIndex);
-  bind(&no_memento_available);
 }
 
 

src/x64/macro-assembler-x64.h

@@ -1412,9 +1412,20 @@ class MacroAssembler: public Assembler {
   // to another type.
   // On entry, receiver_reg should point to the array object.
   // scratch_reg gets clobbered.
-  // If allocation info is present, condition flags are set to equal
+  // If allocation info is present, condition flags are set to equal.
   void TestJSArrayForAllocationMemento(Register receiver_reg,
-                                       Register scratch_reg);
+                                       Register scratch_reg,
+                                       Label* no_memento_found);
+
+  void JumpIfJSArrayHasAllocationMemento(Register receiver_reg,
+                                         Register scratch_reg,
+                                         Label* memento_found) {
+    Label no_memento_found;
+    TestJSArrayForAllocationMemento(receiver_reg, scratch_reg,
+                                    &no_memento_found);
+    j(equal, memento_found);
+    bind(&no_memento_found);
+  }
 
  private:
   // Order general registers are pushed by Pushad.