[compiler] Introduce StringEqualStub and StringNotEqualStub.

src/crankshaft/arm/lithium-codegen-arm.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/crankshaft/arm/lithium-codegen-arm.h"
 
 #include "src/base/bits.h"
 #include "src/code-factory.h"
 #include "src/code-stubs.h"
 #include "src/crankshaft/arm/lithium-gap-resolver-arm.h"
@@ skipping 2348 matching lines @@
       return kNoCondition;
   }
 }
 
 
 void LCodeGen::DoStringCompareAndBranch(LStringCompareAndBranch* instr) {
   DCHECK(ToRegister(instr->context()).is(cp));
   DCHECK(ToRegister(instr->left()).is(r1));
   DCHECK(ToRegister(instr->right()).is(r0));
 
-  Handle<Code> code = CodeFactory::StringCompare(isolate()).code();
-  CallCode(code, RelocInfo::CODE_TARGET, instr);
-  __ cmp(r0, Operand::Zero());
+  if (Token::IsOrderedRelationalCompareOp(instr->op())) {
+    Handle<Code> code = CodeFactory::StringCompare(isolate()).code();
+    CallCode(code, RelocInfo::CODE_TARGET, instr);
+    __ cmp(r0, Operand::Zero());
+  } else {
+    Handle<Code> code = CodeFactory::StringEqual(isolate()).code();
+    CallCode(code, RelocInfo::CODE_TARGET, instr);
+    __ CompareRoot(r0, Heap::kTrueValueRootIndex);
+  }
 
   EmitBranch(instr, ComputeCompareCondition(instr->op()));
 }
 
 
 static InstanceType TestType(HHasInstanceTypeAndBranch* instr) {
   InstanceType from = instr->from();
   InstanceType to = instr->to();
   if (from == FIRST_TYPE) return to;
   DCHECK(from == to || to == LAST_TYPE);
@@ skipping 3089 matching lines @@
 void LCodeGen::DoStoreFrameContext(LStoreFrameContext* instr) {
   Register context = ToRegister(instr->context());
   __ str(context, MemOperand(fp, StandardFrameConstants::kContextOffset));
 }
 
 
 #undef __
 
 }  // namespace internal
 }  // namespace v8