Inline ordered relative compares of mixed double/undefined values.

src/arm/code-stubs-arm.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 6542 matching lines @@
 
   __ bind(&miss);
   GenerateMiss(masm);
 }
 
 
 void ICCompareStub::GenerateHeapNumbers(MacroAssembler* masm) {
   ASSERT(state_ == CompareIC::HEAP_NUMBERS);
 
   Label generic_stub;
-  Label unordered;
+  Label unordered, maybe_undefined1, maybe_undefined2;
   Label miss;
   __ and_(r2, r1, Operand(r0));
   __ JumpIfSmi(r2, &generic_stub);
 
   __ CompareObjectType(r0, r2, r2, HEAP_NUMBER_TYPE);
-  __ b(ne, &miss);
+  __ b(ne, &maybe_undefined1);
   __ CompareObjectType(r1, r2, r2, HEAP_NUMBER_TYPE);
-  __ b(ne, &miss);
+  __ b(ne, &maybe_undefined2);
 
   // Inlining the double comparison and falling back to the general compare
   // stub if NaN is involved or VFP3 is unsupported.
   if (CpuFeatures::IsSupported(VFP3)) {
     CpuFeatures::Scope scope(VFP3);
 
     // Load left and right operand
     __ sub(r2, r1, Operand(kHeapObjectTag));
     __ vldr(d0, r2, HeapNumber::kValueOffset);
     __ sub(r2, r0, Operand(kHeapObjectTag));
     __ vldr(d1, r2, HeapNumber::kValueOffset);
 
     // Compare operands
     __ VFPCompareAndSetFlags(d0, d1);
 
     // Don't base result on status bits when a NaN is involved.
     __ b(vs, &unordered);
 
     // Return a result of -1, 0, or 1, based on status bits.
     __ mov(r0, Operand(EQUAL), LeaveCC, eq);
     __ mov(r0, Operand(LESS), LeaveCC, lt);
     __ mov(r0, Operand(GREATER), LeaveCC, gt);
     __ Ret();
-
-    __ bind(&unordered);
   }
 
+  __ bind(&unordered);
   CompareStub stub(GetCondition(), strict(), NO_COMPARE_FLAGS, r1, r0);
   __ bind(&generic_stub);
   __ Jump(stub.GetCode(), RelocInfo::CODE_TARGET);
 
+  __ bind(&maybe_undefined1);
+  if (Token::IsOrderedRelationalCompareOp(op_)) {
+    __ CompareRoot(r0, Heap::kUndefinedValueRootIndex);
+    __ b(ne, &miss);
+    __ CompareObjectType(r1, r2, r2, HEAP_NUMBER_TYPE);
+    __ b(ne, &maybe_undefined2);
+    __ jmp(&unordered);
+  }
+
+  __ bind(&maybe_undefined2);
+  if (Token::IsOrderedRelationalCompareOp(op_)) {
+    __ CompareRoot(r1, Heap::kUndefinedValueRootIndex);
+    __ b(eq, &unordered);
+  }
+
   __ bind(&miss);
   GenerateMiss(masm);
 }
 
 
 void ICCompareStub::GenerateSymbols(MacroAssembler* masm) {
   ASSERT(state_ == CompareIC::SYMBOLS);
   Label miss;
 
   // Registers containing left and right operands respectively.
@@ skipping 767 matching lines @@
   __ StoreNumberToDoubleElements(r0, r3, r1, r5, r6, r7, r9, r2,
                                  &slow_elements);
   __ Ret();
 }
 
 #undef __
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_ARM