MIPS: Fix arguments-branch update per review comments.

src/mips/ic-mips.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 889 matching lines @@
                                                 Register scratch2,
                                                 Register scratch3,
                                                 Label* unmapped_case,
                                                 Label* slow_case) {
   Heap* heap = masm->isolate()->heap();
 
   // Check that the receiver isn't a smi.
   __ JumpIfSmi(object, slow_case);
 
   // Check that the key is a positive smi.
-  __ And(scratch1, scratch1, Operand(0x8000001));
-  __ Branch(slow_case, ne, key, Operand(scratch1));
+  __ And(scratch1, key, Operand(0x8000001));
+  __ Branch(slow_case, ne, scratch1, Operand(zero_reg));
 
   // Load the elements into scratch1 and check its map.
   Handle<Map> arguments_map(heap->non_strict_arguments_elements_map());
   __ lw(scratch1, FieldMemOperand(object, JSObject::kElementsOffset));
   __ CheckMap(scratch1, scratch2, arguments_map, slow_case, DONT_DO_SMI_CHECK);
 
   // Check if element is in the range of mapped arguments. If not, jump
   // to the unmapped lookup with the parameter map in scratch1.
   __ lw(scratch2, FieldMemOperand(scratch1, FixedArray::kLengthOffset));
   __ Subu(scratch2, scratch2, Operand(Smi::FromInt(2)));
@@ skipping 49 matching lines @@
 
 
 void KeyedLoadIC::GenerateNonStrictArguments(MacroAssembler* masm) {
   // ---------- S t a t e --------------
   //  -- lr     : return address
   //  -- a0     : key
   //  -- a1     : receiver
   // -----------------------------------
   Label slow, notin;
   MemOperand mapped_location =
-      GenerateMappedArgumentsLookup(masm, a1, v0, a2, a3, t0, &notin, &slow);
+      GenerateMappedArgumentsLookup(masm, a1, a0, a2, a3, t0, &notin, &slow);
   __ lw(v0, mapped_location);
   __ Ret();
   __ bind(&notin);
   // The unmapped lookup expects that the parameter map is in a2.
   MemOperand unmapped_location =
-      GenerateUnmappedArgumentsLookup(masm, v0, a2, a3, &slow);
+      GenerateUnmappedArgumentsLookup(masm, a0, a2, a3, &slow);
   __ lw(a2, unmapped_location);
   __ Branch(&slow, eq, a2, Operand(a3));
   __ LoadRoot(a3, Heap::kTheHoleValueRootIndex);
   __ mov(v0, a2);
   __ Ret();
   __ bind(&slow);
   GenerateMiss(masm, false);
 }
 
 
 void KeyedStoreIC::GenerateNonStrictArguments(MacroAssembler* masm) {
   // ---------- S t a t e --------------
-  //  -- v0     : value
+  //  -- a0     : value
   //  -- a1     : key
   //  -- a2     : receiver
   //  -- lr     : return address
   // -----------------------------------
   Label slow, notin;
   MemOperand mapped_location =
       GenerateMappedArgumentsLookup(masm, a2, a1, a3, t0, t1, &notin, &slow);
-  __ sw(v0, mapped_location);
-  __ Ret();
+  __ sw(a0, mapped_location);
+  __ Ret(USE_DELAY_SLOT);
+  __ mov(v0, a0);  // (In delay slot) return the value stored in v0.
   __ bind(&notin);
   // The unmapped lookup expects that the parameter map is in a3.
   MemOperand unmapped_location =
       GenerateUnmappedArgumentsLookup(masm, a1, a3, t0, &slow);
-  __ sw(v0, unmapped_location);
-  __ Ret();
+  __ sw(a0, unmapped_location);
+  __ Ret(USE_DELAY_SLOT);
+  __ mov(v0, a0);  // (In delay slot) return the value stored in v0.
   __ bind(&slow);
   GenerateMiss(masm, false);
 }
 
 
 void KeyedCallIC::GenerateNonStrictArguments(MacroAssembler* masm,
                                              int argc) {
   // ----------- S t a t e -------------
   //  -- a2    : name
   //  -- lr    : return address
@@ skipping 699 matching lines @@
     Register reg = Register::from_code(Assembler::GetRs(instr_at_patch));
     patcher.masm()->andi(at, reg, kSmiTagMask);
     patcher.ChangeBranchCondition(eq);
   }
 }
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_MIPS