MIPS: Inline inequality compares of strings into CompareICStub

src/mips/code-stubs-mips.cc

 // Copyright 2012 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 6877 matching lines @@
 
   __ bind(&miss);
   GenerateMiss(masm);
 }
 
 
 void ICCompareStub::GenerateStrings(MacroAssembler* masm) {
   ASSERT(state_ == CompareIC::STRINGS);
   Label miss;
 
+  bool equality = Token::IsEqualityOp(op_);
+
   // Registers containing left and right operands respectively.
   Register left = a1;
   Register right = a0;
   Register tmp1 = a2;
   Register tmp2 = a3;
   Register tmp3 = t0;
   Register tmp4 = t1;
   Register tmp5 = t2;
 
   // Check that both operands are heap objects.
@@ skipping 16 matching lines @@
   STATIC_ASSERT(kSmiTag == 0);
   __ Branch(&left_ne_right, ne, left, Operand(right), USE_DELAY_SLOT);
   __ mov(v0, zero_reg);  // In the delay slot.
   __ Ret();
   __ bind(&left_ne_right);
 
   // Handle not identical strings.
 
   // Check that both strings are symbols. If they are, we're done
   // because we already know they are not identical.
-  ASSERT(GetCondition() == eq);
-  STATIC_ASSERT(kSymbolTag != 0);
-  __ And(tmp3, tmp1, Operand(tmp2));
-  __ And(tmp5, tmp3, Operand(kIsSymbolMask));
-  Label is_symbol;
-  __ Branch(&is_symbol, eq, tmp5, Operand(zero_reg), USE_DELAY_SLOT);
-  __ mov(v0, a0);  // In the delay slot.
-  // Make sure a0 is non-zero. At this point input operands are
-  // guaranteed to be non-zero.
-  ASSERT(right.is(a0));
-  __ Ret();
-  __ bind(&is_symbol);
+  if (equality) {
+    ASSERT(GetCondition() == eq);
+    STATIC_ASSERT(kSymbolTag != 0);
+    __ And(tmp3, tmp1, Operand(tmp2));
+    __ And(tmp5, tmp3, Operand(kIsSymbolMask));
+    Label is_symbol;
+    __ Branch(&is_symbol, eq, tmp5, Operand(zero_reg), USE_DELAY_SLOT);
+    __ mov(v0, a0);  // In the delay slot.
+    // Make sure a0 is non-zero. At this point input operands are
+    // guaranteed to be non-zero.
+    ASSERT(right.is(a0));
+    __ Ret();
+    __ bind(&is_symbol);
+  }
 
   // Check that both strings are sequential ASCII.
   Label runtime;
-  __ JumpIfBothInstanceTypesAreNotSequentialAscii(tmp1, tmp2, tmp3, tmp4,
-                                                  &runtime);
+  __ JumpIfBothInstanceTypesAreNotSequentialAscii(
+      tmp1, tmp2, tmp3, tmp4, &runtime);
 
   // Compare flat ASCII strings. Returns when done.
-  StringCompareStub::GenerateFlatAsciiStringEquals(
-      masm, left, right, tmp1, tmp2, tmp3);
+  if (equality) {
+    StringCompareStub::GenerateFlatAsciiStringEquals(
+        masm, left, right, tmp1, tmp2, tmp3);
+  } else {
+    StringCompareStub::GenerateCompareFlatAsciiStrings(
+        masm, left, right, tmp1, tmp2, tmp3, tmp4);
+  }
 
   // Handle more complex cases in runtime.
   __ bind(&runtime);
   __ Push(left, right);
-  __ TailCallRuntime(Runtime::kStringEquals, 2, 1);
+  if (equality) {
+    __ TailCallRuntime(Runtime::kStringEquals, 2, 1);
+  } else {
+    __ TailCallRuntime(Runtime::kStringCompare, 2, 1);
+  }
 
   __ bind(&miss);
   GenerateMiss(masm);
 }
 
 
 void ICCompareStub::GenerateObjects(MacroAssembler* masm) {
   ASSERT(state_ == CompareIC::OBJECTS);
   Label miss;
   __ And(a2, a1, Operand(a0));
@@ skipping 699 matching lines @@
   __ Ret(USE_DELAY_SLOT);
   __ mov(v0, a0);
 }
 
 
 #undef __
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_MIPS