Ensure HAllocateObject always allocates in new-space.

This is needed so that we can start removing write-barriers in optimized
code if we can prove that the receiver object is always in new-space.

TEST=cctest/test-heap/OptimizedAllocationAlwaysInNewSpace

Review URL: https://chromiumcodereview.appspot.com/10008007

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@11243 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

diff --git a/src/arm/lithium-codegen-arm.cc b/src/arm/lithium-codegen-arm.cc
index 7a099cc..7c37e8e 100644 (file)
--- a/src/arm/lithium-codegen-arm.cc
+++ b/src/arm/lithium-codegen-arm.cc
@@ -4472,6 +4472,14 @@ void LCodeGen::DoAllocateObject(LAllocateObject* instr) {
                         deferred->entry(),
                         TAG_OBJECT);
 
+  __ bind(deferred->exit());
+  if (FLAG_debug_code) {
+    Label is_in_new_space;
+    __ JumpIfInNewSpace(result, scratch, &is_in_new_space);
+    __ Abort("Allocated object is not in new-space");
+    __ bind(&is_in_new_space);
+  }
+
   // Load the initial map.
   Register map = scratch;
   __ LoadHeapObject(map, constructor);
@@ -4490,14 +4498,14 @@ void LCodeGen::DoAllocateObject(LAllocateObject* instr) {
       __ str(scratch, FieldMemOperand(result, property_offset));
     }
   }
-
-  __ bind(deferred->exit());
 }
 
 
 void LCodeGen::DoDeferredAllocateObject(LAllocateObject* instr) {
   Register result = ToRegister(instr->result());
   Handle<JSFunction> constructor = instr->hydrogen()->constructor();
+  Handle<Map> initial_map(constructor->initial_map());
+  int instance_size = initial_map->instance_size();
 
   // TODO(3095996): Get rid of this. For now, we need to make the
   // result register contain a valid pointer because it is already
@@ -4505,9 +4513,9 @@ void LCodeGen::DoDeferredAllocateObject(LAllocateObject* instr) {
   __ mov(result, Operand(0));
 
   PushSafepointRegistersScope scope(this, Safepoint::kWithRegisters);
-  __ LoadHeapObject(r0, constructor);
+  __ mov(r0, Operand(Smi::FromInt(instance_size)));
   __ push(r0);
-  CallRuntimeFromDeferred(Runtime::kNewObject, 1, instr);
+  CallRuntimeFromDeferred(Runtime::kAllocateInNewSpace, 1, instr);
   __ StoreToSafepointRegisterSlot(r0, result);
 }
 

diff --git a/src/hydrogen-instructions.h b/src/hydrogen-instructions.h
index 4a5df49..d0dd568 100644 (file)
--- a/src/hydrogen-instructions.h
+++ b/src/hydrogen-instructions.h
@@ -4406,6 +4406,9 @@ class HAllocateObject: public HTemplateInstruction<1> {
     set_representation(Representation::Tagged());
   }
 
+  // Maximum instance size for which allocations will be inlined.
+  static const int kMaxSize = 64 * kPointerSize;
+
   HValue* context() { return OperandAt(0); }
   Handle<JSFunction> constructor() { return constructor_; }
 

diff --git a/src/hydrogen.cc b/src/hydrogen.cc
index ae31a14..f9d4191 100644 (file)
--- a/src/hydrogen.cc
+++ b/src/hydrogen.cc
@@ -6048,7 +6048,8 @@ void HGraphBuilder::VisitCall(Call* expr) {
 // Checks whether allocation using the given constructor can be inlined.
 static bool IsAllocationInlineable(Handle<JSFunction> constructor) {
   return constructor->has_initial_map() &&
-      constructor->initial_map()->instance_type() == JS_OBJECT_TYPE;
+      constructor->initial_map()->instance_type() == JS_OBJECT_TYPE &&
+      constructor->initial_map()->instance_size() < HAllocateObject::kMaxSize;
 }
 
 

diff --git a/src/ia32/lithium-codegen-ia32.cc b/src/ia32/lithium-codegen-ia32.cc
index 67e2dca..72f59d0 100644 (file)
--- a/src/ia32/lithium-codegen-ia32.cc
+++ b/src/ia32/lithium-codegen-ia32.cc
@@ -4306,6 +4306,14 @@ void LCodeGen::DoAllocateObject(LAllocateObject* instr) {
                         deferred->entry(),
                         TAG_OBJECT);
 
+  __ bind(deferred->exit());
+  if (FLAG_debug_code) {
+    Label is_in_new_space;
+    __ JumpIfInNewSpace(result, scratch, &is_in_new_space);
+    __ Abort("Allocated object is not in new-space");
+    __ bind(&is_in_new_space);
+  }
+
   // Load the initial map.
   Register map = scratch;
   __ LoadHeapObject(scratch, constructor);
@@ -4340,14 +4348,14 @@ void LCodeGen::DoAllocateObject(LAllocateObject* instr) {
       __ mov(FieldOperand(result, property_offset), scratch);
     }
   }
-
-  __ bind(deferred->exit());
 }
 
 
 void LCodeGen::DoDeferredAllocateObject(LAllocateObject* instr) {
   Register result = ToRegister(instr->result());
   Handle<JSFunction> constructor = instr->hydrogen()->constructor();
+  Handle<Map> initial_map(constructor->initial_map());
+  int instance_size = initial_map->instance_size();
 
   // TODO(3095996): Get rid of this. For now, we need to make the
   // result register contain a valid pointer because it is already
@@ -4355,8 +4363,9 @@ void LCodeGen::DoDeferredAllocateObject(LAllocateObject* instr) {
   __ Set(result, Immediate(0));
 
   PushSafepointRegistersScope scope(this);
-  __ PushHeapObject(constructor);
-  CallRuntimeFromDeferred(Runtime::kNewObject, 1, instr, instr->context());
+  __ push(Immediate(Smi::FromInt(instance_size)));
+  CallRuntimeFromDeferred(
+      Runtime::kAllocateInNewSpace, 1, instr, instr->context());
   __ StoreToSafepointRegisterSlot(result, eax);
 }
 

diff --git a/src/mips/lithium-codegen-mips.cc b/src/mips/lithium-codegen-mips.cc
index 2af9d6f..e4de40f 100644 (file)
--- a/src/mips/lithium-codegen-mips.cc
+++ b/src/mips/lithium-codegen-mips.cc
@@ -4367,6 +4367,14 @@ void LCodeGen::DoAllocateObject(LAllocateObject* instr) {
                         deferred->entry(),
                         TAG_OBJECT);
 
+  __ bind(deferred->exit());
+  if (FLAG_debug_code) {
+    Label is_in_new_space;
+    __ JumpIfInNewSpace(result, scratch, &is_in_new_space);
+    __ Abort("Allocated object is not in new-space");
+    __ bind(&is_in_new_space);
+  }
+
   // Load the initial map.
   Register map = scratch;
   __ LoadHeapObject(map, constructor);
@@ -4385,14 +4393,14 @@ void LCodeGen::DoAllocateObject(LAllocateObject* instr) {
       __ sw(scratch, FieldMemOperand(result, property_offset));
     }
   }
-
-  __ bind(deferred->exit());
 }
 
 
 void LCodeGen::DoDeferredAllocateObject(LAllocateObject* instr) {
   Register result = ToRegister(instr->result());
   Handle<JSFunction> constructor = instr->hydrogen()->constructor();
+  Handle<Map> initial_map(constructor->initial_map());
+  int instance_size = initial_map->instance_size();
 
   // TODO(3095996): Get rid of this. For now, we need to make the
   // result register contain a valid pointer because it is already
@@ -4400,9 +4408,9 @@ void LCodeGen::DoDeferredAllocateObject(LAllocateObject* instr) {
   __ mov(result, zero_reg);
 
   PushSafepointRegistersScope scope(this, Safepoint::kWithRegisters);
-  __ LoadHeapObject(a0, constructor);
+  __ li(a0, Operand(Smi::FromInt(instance_size)));
   __ push(a0);
-  CallRuntimeFromDeferred(Runtime::kNewObject, 1, instr);
+  CallRuntimeFromDeferred(Runtime::kAllocateInNewSpace, 1, instr);
   __ StoreToSafepointRegisterSlot(v0, result);
 }
 

diff --git a/src/x64/lithium-codegen-x64.cc b/src/x64/lithium-codegen-x64.cc
index 1f5ec4b..56ba6f3 100644 (file)
--- a/src/x64/lithium-codegen-x64.cc
+++ b/src/x64/lithium-codegen-x64.cc
@@ -4080,6 +4080,14 @@ void LCodeGen::DoAllocateObject(LAllocateObject* instr) {
                         deferred->entry(),
                         TAG_OBJECT);
 
+  __ bind(deferred->exit());
+  if (FLAG_debug_code) {
+    Label is_in_new_space;
+    __ JumpIfInNewSpace(result, scratch, &is_in_new_space);
+    __ Abort("Allocated object is not in new-space");
+    __ bind(&is_in_new_space);
+  }
+
   // Load the initial map.
   Register map = scratch;
   __ LoadHeapObject(scratch, constructor);
@@ -4114,14 +4122,14 @@ void LCodeGen::DoAllocateObject(LAllocateObject* instr) {
       __ movq(FieldOperand(result, property_offset), scratch);
     }
   }
-
-  __ bind(deferred->exit());
 }
 
 
 void LCodeGen::DoDeferredAllocateObject(LAllocateObject* instr) {
   Register result = ToRegister(instr->result());
   Handle<JSFunction> constructor = instr->hydrogen()->constructor();
+  Handle<Map> initial_map(constructor->initial_map());
+  int instance_size = initial_map->instance_size();
 
   // TODO(3095996): Get rid of this. For now, we need to make the
   // result register contain a valid pointer because it is already
@@ -4129,8 +4137,8 @@ void LCodeGen::DoDeferredAllocateObject(LAllocateObject* instr) {
   __ Set(result, 0);
 
   PushSafepointRegistersScope scope(this);
-  __ PushHeapObject(constructor);
-  CallRuntimeFromDeferred(Runtime::kNewObject, 1, instr);
+  __ Push(Smi::FromInt(instance_size));
+  CallRuntimeFromDeferred(Runtime::kAllocateInNewSpace, 1, instr);
   __ StoreToSafepointRegisterSlot(result, rax);
 }
 

diff --git a/test/cctest/test-heap.cc b/test/cctest/test-heap.cc
index f97bf17..9a5f24e 100644 (file)
--- a/test/cctest/test-heap.cc
+++ b/test/cctest/test-heap.cc
@@ -1264,9 +1264,9 @@ static void FillUpNewSpace(NewSpace* new_space) {
   v8::HandleScope scope;
   AlwaysAllocateScope always_allocate;
   intptr_t available = new_space->EffectiveCapacity() - new_space->Size();
-  intptr_t number_of_fillers = (available / FixedArray::SizeFor(1000)) - 10;
+  intptr_t number_of_fillers = (available / FixedArray::SizeFor(32)) - 1;
   for (intptr_t i = 0; i < number_of_fillers; i++) {
-    CHECK(HEAP->InNewSpace(*FACTORY->NewFixedArray(1000, NOT_TENURED)));
+    CHECK(HEAP->InNewSpace(*FACTORY->NewFixedArray(32, NOT_TENURED)));
   }
 }
 
@@ -1680,3 +1680,33 @@ TEST(ResetSharedFunctionInfoCountersDuringMarkSweep) {
   CHECK_EQ(0, f->shared()->opt_count());
   CHECK_EQ(0, f->shared()->code()->profiler_ticks());
 }
+
+
+// Test that HAllocateObject will always return an object in new-space.
+TEST(OptimizedAllocationAlwaysInNewSpace) {
+  i::FLAG_allow_natives_syntax = true;
+  InitializeVM();
+  if (!i::V8::UseCrankshaft() || i::FLAG_always_opt) return;
+  v8::HandleScope scope;
+
+  FillUpNewSpace(HEAP->new_space());
+  AlwaysAllocateScope always_allocate;
+  v8::Local<v8::Value> res = CompileRun(
+      "function c(x) {"
+      "  this.x = x;"
+      "  for (var i = 0; i < 32; i++) {"
+      "    this['x' + i] = x;"
+      "  }"
+      "}"
+      "function f(x) { return new c(x); };"
+      "f(1); f(2); f(3);"
+      "%OptimizeFunctionOnNextCall(f);"
+      "f(4);");
+  CHECK(res->IsObject());
+  CHECK(res->ToObject()->GetRealNamedProperty(v8_str("x"))->Int32Value() == 4);
+
+  Handle<JSObject> o =
+      v8::Utils::OpenHandle(*v8::Handle<v8::Object>::Cast(res));
+
+  CHECK(HEAP->InNewSpace(*o));
+}