Compare IC: add SYMBOLS state.

src/x64/code-stubs-x64.cc

 // Copyright 2011 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 4721 matching lines @@
 
   CompareStub stub(GetCondition(), strict(), NO_COMPARE_FLAGS);
   __ bind(&generic_stub);
   __ jmp(stub.GetCode(), RelocInfo::CODE_TARGET);
 
   __ bind(&miss);
   GenerateMiss(masm);
 }
 
 
+void ICCompareStub::GenerateSymbols(MacroAssembler* masm) {
+  ASSERT(state_ == CompareIC::SYMBOLS);
+  ASSERT(GetCondition() == equal);
+
+  // Registers containing left and right operands respectively.
+  Register left = rdx;
+  Register right = rax;
+  Register tmp1 = rcx;
+  Register tmp2 = rbx;
+
+  // Check that both operands are heap objects.
+  NearLabel miss;
+  Condition cond = masm->CheckEitherSmi(left, right, tmp1);
+  __ j(cond, &miss);
+
+  // Check that both operands are symbols.
+  __ movq(tmp1, FieldOperand(left, HeapObject::kMapOffset));
+  __ movq(tmp2, FieldOperand(right, HeapObject::kMapOffset));
+  __ movzxbq(tmp1, FieldOperand(tmp1, Map::kInstanceTypeOffset));
+  __ movzxbq(tmp2, FieldOperand(tmp2, Map::kInstanceTypeOffset));
+  STATIC_ASSERT(kSymbolTag != 0);
+  __ and_(tmp1, tmp2);
+  __ testb(tmp1, Immediate(kIsSymbolMask));
+  __ j(zero, &miss);
+
+  // Symbols are compared by identity.
+  NearLabel done;
+  __ cmpq(left, right);
+  // Make sure rax is non-zero. At this point input operands are
+  // guaranteed to be non-zero.
+  ASSERT(right.is(rax));
+  __ j(not_equal, &done);
+  STATIC_ASSERT(EQUAL == 0);
+  STATIC_ASSERT(kSmiTag == 0);
+  __ Move(rax, Smi::FromInt(EQUAL));
+  __ bind(&done);
+  __ ret(0);
+
+  __ bind(&miss);
+  GenerateMiss(masm);
+}
+
+
 void ICCompareStub::GenerateStrings(MacroAssembler* masm) {
   ASSERT(state_ == CompareIC::STRINGS);
   ASSERT(GetCondition() == equal);
   Label miss;
 
   // Registers containing left and right operands respectively.
   Register left = rdx;
   Register right = rax;
   Register tmp1 = rcx;
   Register tmp2 = rbx;
   Register tmp3 = rdi;
 
   // Check that both operands are heap objects.
   Condition cond = masm->CheckEitherSmi(left, right, tmp1);
   __ j(cond, &miss);
 
   // Check that both operands are strings. This leaves the instance
   // types loaded in tmp1 and tmp2.
   __ movq(tmp1, FieldOperand(left, HeapObject::kMapOffset));
   __ movq(tmp2, FieldOperand(right, HeapObject::kMapOffset));
   __ movzxbq(tmp1, FieldOperand(tmp1, Map::kInstanceTypeOffset));
   __ movzxbq(tmp2, FieldOperand(tmp2, Map::kInstanceTypeOffset));
   __ movq(tmp3, tmp1);
   STATIC_ASSERT(kNotStringTag != 0);
   __ or_(tmp3, tmp2);
-  __ testl(tmp3, Immediate(kIsNotStringMask));
+  __ testb(tmp3, Immediate(kIsNotStringMask));
   __ j(not_zero, &miss);
 
   // Fast check for identical strings.
   NearLabel not_same;
   __ cmpq(left, right);
   __ j(not_equal, &not_same);
   STATIC_ASSERT(EQUAL == 0);
   STATIC_ASSERT(kSmiTag == 0);
   __ Move(rax, Smi::FromInt(EQUAL));
   __ ret(0);
 
   // Handle not identical strings.
   __ bind(&not_same);
 
   // Check that both strings are symbols. If they are, we're done
   // because we already know they are not identical.
   NearLabel do_compare;
   STATIC_ASSERT(kSymbolTag != 0);
   __ and_(tmp1, tmp2);
-  __ testl(tmp1, Immediate(kIsSymbolMask));
+  __ testb(tmp1, Immediate(kIsSymbolMask));
   __ j(zero, &do_compare);
   // Make sure rax is non-zero. At this point input operands are
   // guaranteed to be non-zero.
   ASSERT(right.is(rax));
   __ ret(0);
 
   // Check that both strings are sequential ASCII.
   Label runtime;
   __ bind(&do_compare);
   __ JumpIfNotBothSequentialAsciiStrings(left, right, tmp1, tmp2, &runtime);
@@ skipping 261 matching lines @@
   __ Drop(1);
   __ ret(2 * kPointerSize);
 }
 
 
 #undef __
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_X64