[builtins] One runtime fallback is enough for the String constructor.

If inline allocation fails, we can just use the %NewObject fallback,
which will do the right thing. We don't need a dedicated fallback to
%AllocateInNewSpace.

R=verwaest@chromium.org

Review URL: https://codereview.chromium.org/1440193003

Cr-Commit-Position: refs/heads/master@{#32000}

src/arm/builtins-arm.cc

@@ -251,7 +251,12 @@ void Builtins::Generate_StringConstructor_ConstructStub(MacroAssembler* masm) {
     __ bind(&done_convert);
   }
 
-  // 3. Allocate a JSValue wrapper for the string.
+  // 3. Check if original constructor and constructor differ.
+  Label new_object;
+  __ cmp(r1, r3);
+  __ b(ne, &new_object);
+
+  // 4. Allocate a JSValue wrapper for the string.
   {
     // ----------- S t a t e -------------
     //  -- r2 : the first argument
@@ -259,15 +264,7 @@ void Builtins::Generate_StringConstructor_ConstructStub(MacroAssembler* masm) {
     //  -- r3 : original constructor
     //  -- lr : return address
     // -----------------------------------
-
-    Label allocate, done_allocate, rt_call;
-
-    // Fall back to runtime if the original constructor and function differ.
-    __ cmp(r1, r3);
-    __ b(ne, &rt_call);
-
-    __ Allocate(JSValue::kSize, r0, r3, r4, &allocate, TAG_OBJECT);
-    __ bind(&done_allocate);
+    __ Allocate(JSValue::kSize, r0, r4, r5, &new_object, TAG_OBJECT);
 
     // Initialize the JSValue in r0.
     __ LoadGlobalFunctionInitialMap(r1, r3, r4);
@@ -278,30 +275,18 @@ void Builtins::Generate_StringConstructor_ConstructStub(MacroAssembler* masm) {
     __ str(r2, FieldMemOperand(r0, JSValue::kValueOffset));
     STATIC_ASSERT(JSValue::kSize == 4 * kPointerSize);
     __ Ret();
-
-    // Fallback to the runtime to allocate in new space.
-    __ bind(&allocate);
-    {
-      FrameAndConstantPoolScope scope(masm, StackFrame::INTERNAL);
-      __ Move(r3, Smi::FromInt(JSValue::kSize));
-      __ Push(r1, r2, r3);
-      __ CallRuntime(Runtime::kAllocateInNewSpace, 1);
-      __ Pop(r1, r2);
   }
-    __ b(&done_allocate);
 
-    // Fallback to the runtime to create new object.
-    __ bind(&rt_call);
+  // 5. Fallback to the runtime to create new object.
+  __ bind(&new_object);
   {
-      FrameScope scope(masm, StackFrame::INTERNAL);
-      __ Push(r1, r2);
-      __ Push(r1, r3);  // constructor function, original constructor
+    FrameAndConstantPoolScope scope(masm, StackFrame::INTERNAL);
+    __ Push(r2, r1, r3);  // first argument, constructor, original constructor
     __ CallRuntime(Runtime::kNewObject, 2);
-      __ Pop(r1, r2);
+    __ Pop(r2);
   }
   __ str(r2, FieldMemOperand(r0, JSValue::kValueOffset));
   __ Ret();
-  }
 }
 
 

src/arm64/builtins-arm64.cc

@@ -247,7 +247,12 @@ void Builtins::Generate_StringConstructor_ConstructStub(MacroAssembler* masm) {
     __ Bind(&done_convert);
   }
 
-  // 3. Allocate a JSValue wrapper for the string.
+  // 3. Check if original constructor and constructor differ.
+  Label new_object;
+  __ Cmp(x1, x3);
+  __ B(ne, &new_object);
+
+  // 4. Allocate a JSValue wrapper for the string.
   {
     // ----------- S t a t e -------------
     //  -- x2 : the first argument
@@ -255,15 +260,7 @@ void Builtins::Generate_StringConstructor_ConstructStub(MacroAssembler* masm) {
     //  -- x3 : original constructor
     //  -- lr : return address
     // -----------------------------------
-
-    Label allocate, done_allocate, rt_call;
-
-    // Fall back to runtime if the original constructor and function differ.
-    __ cmp(x1, x3);
-    __ B(ne, &rt_call);
-
-    __ Allocate(JSValue::kSize, x0, x3, x4, &allocate, TAG_OBJECT);
-    __ Bind(&done_allocate);
+    __ Allocate(JSValue::kSize, x0, x4, x5, &new_object, TAG_OBJECT);
 
     // Initialize the JSValue in eax.
     __ LoadGlobalFunctionInitialMap(x1, x3, x4);
@@ -274,29 +271,19 @@ void Builtins::Generate_StringConstructor_ConstructStub(MacroAssembler* masm) {
     __ Str(x2, FieldMemOperand(x0, JSValue::kValueOffset));
     STATIC_ASSERT(JSValue::kSize == 4 * kPointerSize);
     __ Ret();
-
-    // Fallback to the runtime to allocate in new space.
-    __ Bind(&allocate);
-    {
-      FrameScope scope(masm, StackFrame::INTERNAL);
-      __ Push(x1, x2);
-      __ Push(Smi::FromInt(JSValue::kSize));
-      __ CallRuntime(Runtime::kAllocateInNewSpace, 1);
-      __ Pop(x2, x1);
   }
-    __ B(&done_allocate);
 
-    // Fallback to the runtime to create new object.
-    __ bind(&rt_call);
+  // 5. Fallback to the runtime to create new object.
+  __ bind(&new_object);
   {
     FrameScope scope(masm, StackFrame::INTERNAL);
-      __ Push(x1, x2, x1, x3);  // constructor function, original constructor
+    __ Push(x2, x1);  // first argument, constructor
+    __ Push(x1, x3);  // constructor, original constructor
     __ CallRuntime(Runtime::kNewObject, 2);
-      __ Pop(x2, x1);
+    __ Pop(x1, x2);
   }
   __ Str(x2, FieldMemOperand(x0, JSValue::kValueOffset));
   __ Ret();
-  }
 }
 
 

src/ia32/builtins-ia32.cc

@@ -1407,22 +1407,19 @@ void Builtins::Generate_StringConstructor_ConstructStub(MacroAssembler* masm) {
     __ bind(&done_convert);
   }
 
-  // 3. Allocate a JSValue wrapper for the string.
+  // 3. Check if original constructor and constructor differ.
+  Label new_object;
+  __ cmp(edx, edi);
+  __ j(not_equal, &new_object);
+
+  // 4. Allocate a JSValue wrapper for the string.
   {
     // ----------- S t a t e -------------
     //  -- ebx : the first argument
     //  -- edi : constructor function
     //  -- edx : original constructor
     // -----------------------------------
-
-    Label allocate, done_allocate, rt_call;
-
-    // Fall back to runtime if the original constructor and constructor differ.
-    __ cmp(edx, edi);
-    __ j(not_equal, &rt_call);
-
-    __ Allocate(JSValue::kSize, eax, ecx, no_reg, &allocate, TAG_OBJECT);
-    __ bind(&done_allocate);
+    __ Allocate(JSValue::kSize, eax, ecx, no_reg, &new_object, TAG_OBJECT);
 
     // Initialize the JSValue in eax.
     __ LoadGlobalFunctionInitialMap(edi, ecx);
@@ -1434,35 +1431,19 @@ void Builtins::Generate_StringConstructor_ConstructStub(MacroAssembler* masm) {
     __ mov(FieldOperand(eax, JSValue::kValueOffset), ebx);
     STATIC_ASSERT(JSValue::kSize == 4 * kPointerSize);
     __ Ret();
-
-    // Fallback to the runtime to allocate in new space.
-    __ bind(&allocate);
-    {
-      FrameScope scope(masm, StackFrame::INTERNAL);
-      __ Push(ebx);
-      __ Push(edi);
-      __ Push(Smi::FromInt(JSValue::kSize));
-      __ CallRuntime(Runtime::kAllocateInNewSpace, 1);
-      __ Pop(edi);
-      __ Pop(ebx);
   }
-    __ jmp(&done_allocate);
 
-    // Fallback to the runtime to create new object.
-    __ bind(&rt_call);
+  // 5. Fallback to the runtime to create new object.
+  __ bind(&new_object);
   {
     FrameScope scope(masm, StackFrame::INTERNAL);
-      __ Push(ebx);
-      __ Push(edi);
+    __ Push(ebx);  // the first argument
     __ Push(edi);  // constructor function
     __ Push(edx);  // original constructor
     __ CallRuntime(Runtime::kNewObject, 2);
-      __ Pop(edi);
-      __ Pop(ebx);
+    __ Pop(FieldOperand(eax, JSValue::kValueOffset));
   }
-    __ mov(FieldOperand(eax, JSValue::kValueOffset), ebx);
   __ Ret();
-  }
 }
 
 

src/ia32/macro-assembler-ia32.h

@@ -841,6 +841,7 @@ class MacroAssembler: public Assembler {
   void Push(const Operand& src) { push(src); }
   void Push(Immediate value) { push(value); }
   void Pop(Register dst) { pop(dst); }
+  void Pop(const Operand& dst) { pop(dst); }
   void PushReturnAddressFrom(Register src) { push(src); }
   void PopReturnAddressTo(Register dst) { pop(dst); }
 

src/mips/builtins-mips.cc

@@ -267,7 +267,11 @@ void Builtins::Generate_StringConstructor_ConstructStub(MacroAssembler* masm) {
     __ bind(&done_convert);
   }
 
-  // 3. Allocate a JSValue wrapper for the string.
+  // 3. Check if original constructor and constructor differ.
+  Label new_object;
+  __ Branch(&new_object, ne, a1, Operand(a3));
+
+  // 4. Allocate a JSValue wrapper for the string.
   {
     // ----------- S t a t e -------------
     //  -- a0 : the first argument
@@ -275,14 +279,7 @@ void Builtins::Generate_StringConstructor_ConstructStub(MacroAssembler* masm) {
     //  -- a3 : original constructor
     //  -- ra : return address
     // -----------------------------------
-
-    Label allocate, done_allocate, rt_call;
-
-    // Fall back to runtime if the original constructor and function differ.
-    __ Branch(&rt_call, ne, a1, Operand(a3));
-
-    __ Allocate(JSValue::kSize, v0, a2, a3, &allocate, TAG_OBJECT);
-    __ bind(&done_allocate);
+    __ Allocate(JSValue::kSize, v0, a2, t0, &new_object, TAG_OBJECT);
 
     // Initialize the JSValue in eax.
     __ LoadGlobalFunctionInitialMap(a1, a2, a3);
@@ -293,29 +290,18 @@ void Builtins::Generate_StringConstructor_ConstructStub(MacroAssembler* masm) {
     __ Ret(USE_DELAY_SLOT);
     __ sw(a0, FieldMemOperand(v0, JSValue::kValueOffset));
     STATIC_ASSERT(JSValue::kSize == 4 * kPointerSize);
-
-    // Fallback to the runtime to allocate in new space.
-    __ bind(&allocate);
-    {
-      FrameScope scope(masm, StackFrame::INTERNAL);
-      __ Move(a2, Smi::FromInt(JSValue::kSize));
-      __ Push(a0, a1, a2);
-      __ CallRuntime(Runtime::kAllocateInNewSpace, 1);
-      __ Pop(a0, a1);
   }
-    __ jmp(&done_allocate);
 
-    // Fallback to the runtime to create new object.
-    __ bind(&rt_call);
+  // 5. Fallback to the runtime to create new object.
+  __ bind(&new_object);
   {
     FrameScope scope(masm, StackFrame::INTERNAL);
-      __ Push(a0, a1, a1, a3);  // constructor function, original constructor
+    __ Push(a0, a1, a3);  // first argument, constructor, original constructor
     __ CallRuntime(Runtime::kNewObject, 2);
-      __ Pop(a0, a1);
+    __ Pop(a0);
   }
   __ Ret(USE_DELAY_SLOT);
   __ sw(a0, FieldMemOperand(v0, JSValue::kValueOffset));
-  }
 }
 
 

src/mips64/builtins-mips64.cc

@@ -264,7 +264,11 @@ void Builtins::Generate_StringConstructor_ConstructStub(MacroAssembler* masm) {
     __ bind(&done_convert);
   }
 
-  // 3. Allocate a JSValue wrapper for the string.
+  // 3. Check if original constructor and constructor differ.
+  Label new_object;
+  __ Branch(&new_object, ne, a1, Operand(a3));
+
+  // 4. Allocate a JSValue wrapper for the string.
   {
     // ----------- S t a t e -------------
     //  -- a0 : the first argument
@@ -272,14 +276,7 @@ void Builtins::Generate_StringConstructor_ConstructStub(MacroAssembler* masm) {
     //  -- a3 : original constructor
     //  -- ra : return address
     // -----------------------------------
-
-    Label allocate, done_allocate, rt_call;
-
-    // Fall back to runtime if the original constructor and function differ.
-    __ Branch(&rt_call, ne, a1, Operand(a3));
-
-    __ Allocate(JSValue::kSize, v0, a2, a3, &allocate, TAG_OBJECT);
-    __ bind(&done_allocate);
+    __ Allocate(JSValue::kSize, v0, a2, t0, &new_object, TAG_OBJECT);
 
     // Initialize the JSValue in eax.
     __ LoadGlobalFunctionInitialMap(a1, a2, a3);
@@ -290,29 +287,18 @@ void Builtins::Generate_StringConstructor_ConstructStub(MacroAssembler* masm) {
     __ sd(a0, FieldMemOperand(v0, JSValue::kValueOffset));
     STATIC_ASSERT(JSValue::kSize == 4 * kPointerSize);
     __ Ret();
-
-    // Fallback to the runtime to allocate in new space.
-    __ bind(&allocate);
-    {
-      FrameScope scope(masm, StackFrame::INTERNAL);
-      __ Move(a2, Smi::FromInt(JSValue::kSize));
-      __ Push(a0, a1, a2);
-      __ CallRuntime(Runtime::kAllocateInNewSpace, 1);
-      __ Pop(a0, a1);
   }
-    __ jmp(&done_allocate);
 
-    // Fallback to the runtime to create new object.
-    __ bind(&rt_call);
+  // 5. Fallback to the runtime to create new object.
+  __ bind(&new_object);
   {
     FrameScope scope(masm, StackFrame::INTERNAL);
-      __ Push(a0, a1, a1, a3);  // constructor function, original constructor
+    __ Push(a0, a1, a3);  // first argument, constructor, original constructor
     __ CallRuntime(Runtime::kNewObject, 2);
-      __ Pop(a0, a1);
+    __ Pop(a0);
   }
   __ sd(a0, FieldMemOperand(v0, JSValue::kValueOffset));
   __ Ret();
-  }
 }
 
 

src/x64/builtins-x64.cc

@@ -1468,21 +1468,19 @@ void Builtins::Generate_StringConstructor_ConstructStub(MacroAssembler* masm) {
     __ bind(&done_convert);
   }
 
-  // 3. Allocate a JSValue wrapper for the string.
+  // 3. Check if original constructor and constructor differ.
+  Label new_object;
+  __ cmpp(rdx, rdi);
+  __ j(not_equal, &new_object);
+
+  // 4. Allocate a JSValue wrapper for the string.
   {
     // ----------- S t a t e -------------
     //  -- rbx : the first argument
     //  -- rdi : constructor function
     //  -- rdx : original constructor
     // -----------------------------------
-    Label allocate, done_allocate, rt_call;
-
-    // Fall back to runtime if the original constructor and constructor differ.
-    __ cmpp(rdx, rdi);
-    __ j(not_equal, &rt_call);
-
-    __ Allocate(JSValue::kSize, rax, rcx, no_reg, &allocate, TAG_OBJECT);
-    __ bind(&done_allocate);
+    __ Allocate(JSValue::kSize, rax, rcx, no_reg, &new_object, TAG_OBJECT);
 
     // Initialize the JSValue in rax.
     __ LoadGlobalFunctionInitialMap(rdi, rcx);
@@ -1493,35 +1491,19 @@ void Builtins::Generate_StringConstructor_ConstructStub(MacroAssembler* masm) {
     __ movp(FieldOperand(rax, JSValue::kValueOffset), rbx);
     STATIC_ASSERT(JSValue::kSize == 4 * kPointerSize);
     __ Ret();
-
-    // Fallback to the runtime to allocate in new space.
-    __ bind(&allocate);
-    {
-      FrameScope scope(masm, StackFrame::INTERNAL);
-      __ Push(rbx);
-      __ Push(rdi);
-      __ Push(Smi::FromInt(JSValue::kSize));
-      __ CallRuntime(Runtime::kAllocateInNewSpace, 1);
-      __ Pop(rdi);
-      __ Pop(rbx);
   }
-    __ jmp(&done_allocate);
 
-    // Fallback to the runtime to create new object.
-    __ bind(&rt_call);
+  // 5. Fallback to the runtime to create new object.
+  __ bind(&new_object);
   {
     FrameScope scope(masm, StackFrame::INTERNAL);
-      __ Push(rbx);
-      __ Push(rdi);
+    __ Push(rbx);  // the first argument
     __ Push(rdi);  // constructor function
     __ Push(rdx);  // original constructor
     __ CallRuntime(Runtime::kNewObject, 2);
-      __ Pop(rdi);
-      __ Pop(rbx);
+    __ Pop(FieldOperand(rax, JSValue::kValueOffset));
   }
-    __ movp(FieldOperand(rax, JSValue::kValueOffset), rbx);
   __ Ret();
-  }
 }