X87: Eliminate special keyed load string stub in favor of uniform handlers

src/x87/code-stubs-x87.cc

Index: src/x87/code-stubs-x87.cc
diff --git a/src/x87/code-stubs-x87.cc b/src/x87/code-stubs-x87.cc
index 4a6083c25fabca9472da9b8aa20cb163ce7fd1a5..690c3700c47bc300f534941663b386b90a287ebb 100644
--- a/src/x87/code-stubs-x87.cc
+++ b/src/x87/code-stubs-x87.cc
@@ -371,6 +371,37 @@ void LoadIndexedInterceptorStub::Generate(MacroAssembler* masm) {
 }
 
 
+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()));