Customized support for feedback on calls to Array.

src/ia32/code-stubs-ia32.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "v8.h"
 
 #if V8_TARGET_ARCH_IA32
 
 #include "bootstrapper.h"
 #include "code-stubs.h"
@@ skipping 2353 matching lines @@
     __ push(edi);
     __ push(eax);
     __ InvokeBuiltin(Builtins::TO_OBJECT, CALL_FUNCTION);
     __ pop(edi);
   }
   __ mov(Operand(esp, (argc + 1) * kPointerSize), eax);
   __ jmp(cont);
 }
 
 
-void CallFunctionStub::Generate(MacroAssembler* masm) {
+static void CallFunctionNoFeedback(MacroAssembler* masm,
+                                   int argc, bool needs_checks,
+                                   bool call_as_method) {
   // edi : the function to call
   Label slow, non_function, wrap, cont;
 
-  if (NeedsChecks()) {
+  if (needs_checks) {
     // Check that the function really is a JavaScript function.
     __ JumpIfSmi(edi, &non_function);
 
     // Goto slow case if we do not have a function.
     __ CmpObjectType(edi, JS_FUNCTION_TYPE, ecx);
     __ j(not_equal, &slow);
   }
 
   // Fast-case: Just invoke the function.
-  ParameterCount actual(argc_);
+  ParameterCount actual(argc);
 
-  if (CallAsMethod()) {
-    if (NeedsChecks()) {
+  if (call_as_method) {
+    if (needs_checks) {
       EmitContinueIfStrictOrNative(masm, &cont);
     }
 
     // Load the receiver from the stack.
-    __ mov(eax, Operand(esp, (argc_ + 1) * kPointerSize));
+    __ mov(eax, Operand(esp, (argc + 1) * kPointerSize));
 
-    if (NeedsChecks()) {
+    if (call_as_method) {
       __ JumpIfSmi(eax, &wrap);
 
       __ CmpObjectType(eax, FIRST_SPEC_OBJECT_TYPE, ecx);
       __ j(below, &wrap);
     } else {
       __ jmp(&wrap);
     }
 
     __ bind(&cont);
   }
 
   __ InvokeFunction(edi, actual, JUMP_FUNCTION, NullCallWrapper());
 
-  if (NeedsChecks()) {
+  if (needs_checks) {
     // Slow-case: Non-function called.
     __ bind(&slow);
     // (non_function is bound in EmitSlowCase)
-    EmitSlowCase(isolate(), masm, argc_, &non_function);
+    EmitSlowCase(masm->isolate(), masm, argc, &non_function);
   }
 
-  if (CallAsMethod()) {
+  if (call_as_method) {
     __ bind(&wrap);
-    EmitWrapCase(masm, argc_, &cont);
+    EmitWrapCase(masm, argc, &cont);
   }
 }
 
 
+void CallFunctionStub::Generate(MacroAssembler* masm) {
+  CallFunctionNoFeedback(masm, argc_, NeedsChecks(), CallAsMethod());
+}
+
+
 void CallConstructStub::Generate(MacroAssembler* masm) {
   // eax : number of arguments
   // ebx : feedback vector
   // edx : (only if ebx is not the megamorphic symbol) slot in feedback
   //       vector (Smi)
   // edi : constructor function
   Label slow, non_function_call;
 
   // Check that function is not a smi.
   __ JumpIfSmi(edi, &non_function_call);
@@ skipping 56 matching lines @@
 
 
 static void EmitLoadTypeFeedbackVector(MacroAssembler* masm, Register vector) {
   __ mov(vector, Operand(ebp, JavaScriptFrameConstants::kFunctionOffset));
   __ mov(vector, FieldOperand(vector, JSFunction::kSharedFunctionInfoOffset));
   __ mov(vector, FieldOperand(vector,
                               SharedFunctionInfo::kFeedbackVectorOffset));
 }
 
 
+void CallICStub::Generate_MonomorphicArray(MacroAssembler* masm, Label* miss) {
+  // edi - function
+  // ebx - feedback vector
+  // edx - slot id
+  __ LoadGlobalFunction(Context::ARRAY_FUNCTION_INDEX, ecx);
+  __ cmp(edi, ecx);
+  __ j(not_equal, miss);
+
+  __ mov(eax, arg_count());
+  __ mov(ebx, FieldOperand(ebx, edx, times_half_pointer_size,
+                           FixedArray::kHeaderSize));
+  // Verify that ecx contains an AllocationSite
+  __ AssertUndefinedOrAllocationSite(ebx);
+  ArrayConstructorStub stub(masm->isolate(), arg_count());
+  __ TailCallStub(&stub);
+}
+
+
+void CallICStub::Generate_CustomFeedbackCall(MacroAssembler* masm) {
+  // edi - function
+  // ebx - feedback vector
+  // edx - slot id
+  Label miss;
+
+  if (state_.stub_type() == CallIC::MONOMORPHIC_ARRAY) {
+    Generate_MonomorphicArray(masm, &miss);
+  } else {
+    // So far there is only one customer for our custom feedback scheme.
+    UNREACHABLE();
+  }
+
+  __ bind(&miss);
+  GenerateMiss(masm);
+
+  // The slow case, we need this no matter what to complete a call after a miss.
+  CallFunctionNoFeedback(masm,
+                         arg_count(),
+                         true,
+                         CallAsMethod());
+
+  // Unreachable.
+  __ int3();

[danno, 2014/05/16 16:34:11]

I think there might be a macro for this.

[mvstanton, 2014/05/19 13:45:24]

There isn't, code even in the macro assembler uses int3() to indicate "should
not come here." I could make one, something like __ Trap(), which gets used the
same on all platforms, worthwhile?

+}
+
+
 void CallICStub::Generate(MacroAssembler* masm) {
   // edi - function
   // edx - slot id
   Isolate* isolate = masm->isolate();
   Label extra_checks_or_miss, slow_start;
   Label slow, non_function, wrap, cont;
   Label have_js_function;
   int argc = state_.arg_count();
   ParameterCount actual(argc);
 
   EmitLoadTypeFeedbackVector(masm, ebx);
 
+  // the MONOMORPHIC_ARRAY case is handled with a helper function.
+  if (state_.stub_type() != CallIC::DEFAULT) {
+    Generate_CustomFeedbackCall(masm);
+    return;
+  }
+
+  // the MONOMORPHIC_ARRAY case is handled with a helper function.
   // The checks. First, does edi match the recorded monomorphic target?
   __ cmp(edi, FieldOperand(ebx, edx, times_half_pointer_size,
                            FixedArray::kHeaderSize));
   __ j(not_equal, &extra_checks_or_miss);
 
   __ bind(&have_js_function);
   if (state_.CallAsMethod()) {
     EmitContinueIfStrictOrNative(masm, &cont);
 
     // Load the receiver from the stack.
@@ skipping 2604 matching lines @@
                               Operand(ebp, 7 * kPointerSize),
                               NULL);
 }
 
 
 #undef __
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_IA32