Eliminate special keyed load string stub in favor of uniform handlers.

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 "src/v8.h"
 
 #if V8_TARGET_ARCH_IA32
 
 #include "src/base/bits.h"
 #include "src/bootstrapper.h"
@@ skipping 673 matching lines @@
   ExternalReference ref = ExternalReference(
       IC_Utility(IC::kLoadElementWithInterceptor), masm->isolate());
   __ TailCallExternalReference(ref, 2, 1);
 
   __ bind(&slow);
   PropertyAccessCompiler::TailCallBuiltin(
       masm, PropertyAccessCompiler::MissBuiltin(Code::KEYED_LOAD_IC));
 }
 
 
+void LoadIndexedStringStub::Generate(MacroAssembler* masm) {
+  // Return address is on the stack.
+  Label miss;
+
+  Register receiver = LoadDescriptor::ReceiverRegister();
+  Register index = LoadDescriptor::NameRegister();
+  Register scratch = ebx;
+  DCHECK(!scratch.is(receiver) && !scratch.is(index));
+  Register result = eax;
+  DCHECK(!result.is(scratch));
+
+  // TODO(mvstanton): the generator doesn't need to verify that
+  // receiver is a string map, that is done outside the handler.
+  StringCharAtGenerator char_at_generator(receiver, index, scratch, result,
+                                          &miss,  // When not a string.
+                                          &miss,  // When not a number.
+                                          &miss,  // When index out of range.
+                                          STRING_INDEX_IS_ARRAY_INDEX,
+                                          RECEIVER_IS_STRING);
+  char_at_generator.GenerateFast(masm);
+  __ ret(0);
+
+  StubRuntimeCallHelper call_helper;
+  char_at_generator.GenerateSlow(masm, call_helper);
+
+  __ bind(&miss);
+  PropertyAccessCompiler::TailCallBuiltin(
+      masm, PropertyAccessCompiler::MissBuiltin(Code::KEYED_LOAD_IC));
+}
+
+
 void ArgumentsAccessStub::GenerateReadElement(MacroAssembler* masm) {
   // The key is in edx and the parameter count is in eax.
   DCHECK(edx.is(ArgumentsAccessReadDescriptor::index()));
   DCHECK(eax.is(ArgumentsAccessReadDescriptor::parameter_count()));
 
   // The displacement is used for skipping the frame pointer on the
   // stack. It is the offset of the last parameter (if any) relative
   // to the frame pointer.
   static const int kDisplacement = 1 * kPointerSize;
 
@@ skipping 2036 matching lines @@
   }
 }
 
 
 // -------------------------------------------------------------------------
 // StringCharCodeAtGenerator
 
 void StringCharCodeAtGenerator::GenerateFast(MacroAssembler* masm) {
   // If the receiver is a smi trigger the non-string case.
   STATIC_ASSERT(kSmiTag == 0);
-  __ JumpIfSmi(object_, receiver_not_string_);
+  if (check_mode_ == RECEIVER_IS_UNKNOWN) {
+    __ JumpIfSmi(object_, receiver_not_string_);
 
-  // Fetch the instance type of the receiver into result register.
-  __ mov(result_, FieldOperand(object_, HeapObject::kMapOffset));
-  __ movzx_b(result_, FieldOperand(result_, Map::kInstanceTypeOffset));
-  // If the receiver is not a string trigger the non-string case.
-  __ test(result_, Immediate(kIsNotStringMask));
-  __ j(not_zero, receiver_not_string_);
+    // Fetch the instance type of the receiver into result register.
+    __ mov(result_, FieldOperand(object_, HeapObject::kMapOffset));
+    __ movzx_b(result_, FieldOperand(result_, Map::kInstanceTypeOffset));
+    // If the receiver is not a string trigger the non-string case.
+    __ test(result_, Immediate(kIsNotStringMask));
+    __ j(not_zero, receiver_not_string_);
+  }
 
   // If the index is non-smi trigger the non-smi case.
   STATIC_ASSERT(kSmiTag == 0);
   __ JumpIfNotSmi(index_, &index_not_smi_);
   __ bind(&got_smi_index_);
 
   // Check for index out of range.
   __ cmp(index_, FieldOperand(object_, String::kLengthOffset));
   __ j(above_equal, index_out_of_range_);
 
@@ skipping 1934 matching lines @@
                               Operand(ebp, 7 * kPointerSize),
                               NULL);
 }
 
 
 #undef __
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_IA32