[ic][mips][mips64] Ensure store handlers return value in proper register.

src/ic/mips64/ic-mips64.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.
 
 #if V8_TARGET_ARCH_MIPS64
 
 #include "src/codegen.h"
 #include "src/ic/ic.h"
 #include "src/ic/ic-compiler.h"
 #include "src/ic/stub-cache.h"
@@ skipping 478 matching lines @@
     // Add 1 to receiver->length.
     __ Daddu(scratch, key, Operand(Smi::FromInt(1)));
     __ sd(scratch, FieldMemOperand(receiver, JSArray::kLengthOffset));
   }
   // It's irrelevant whether array is smi-only or not when writing a smi.
   __ Daddu(address, elements,
            Operand(FixedArray::kHeaderSize - kHeapObjectTag));
   __ SmiScale(scratch, key, kPointerSizeLog2);
   __ Daddu(address, address, scratch);
   __ sd(value, MemOperand(address));
-  __ Ret();
+  __ Ret(USE_DELAY_SLOT);
+  __ Move(v0, value);  // Ensure the stub returns correct value.
 
   __ bind(&non_smi_value);
   // Escape to elements kind transition case.
   __ CheckFastObjectElements(receiver_map, scratch, &transition_smi_elements);
 
   // Fast elements array, store the value to the elements backing store.
   __ bind(&finish_object_store);
   if (increment_length == kIncrementLength) {
     // Add 1 to receiver->length.
     __ Daddu(scratch, key, Operand(Smi::FromInt(1)));
     __ sd(scratch, FieldMemOperand(receiver, JSArray::kLengthOffset));
   }
   __ Daddu(address, elements,
            Operand(FixedArray::kHeaderSize - kHeapObjectTag));
   __ SmiScale(scratch, key, kPointerSizeLog2);
   __ Daddu(address, address, scratch);
   __ sd(value, MemOperand(address));
   // Update write barrier for the elements array address.
   __ mov(scratch, value);  // Preserve the value which is returned.
   __ RecordWrite(elements, address, scratch, kRAHasNotBeenSaved,
                  kDontSaveFPRegs, EMIT_REMEMBERED_SET, OMIT_SMI_CHECK);
-  __ Ret();
+  __ Ret(USE_DELAY_SLOT);
+  __ Move(v0, value);  // Ensure the stub returns correct value.
 
   __ bind(fast_double);
   if (check_map == kCheckMap) {
     // Check for fast double array case. If this fails, call through to the
     // runtime.
     __ LoadRoot(at, Heap::kFixedDoubleArrayMapRootIndex);
     __ Branch(slow, ne, elements_map, Operand(at));
   }
 
   // HOLECHECK: guards "A[i] double hole?"
@@ skipping 10 matching lines @@
   __ JumpIfDictionaryInPrototypeChain(receiver, elements_map, scratch, slow);
 
   __ bind(&fast_double_without_map_check);
   __ StoreNumberToDoubleElements(value, key, elements, scratch, scratch2,
                                  &transition_double_elements);
   if (increment_length == kIncrementLength) {
     // Add 1 to receiver->length.
     __ Daddu(scratch, key, Operand(Smi::FromInt(1)));
     __ sd(scratch, FieldMemOperand(receiver, JSArray::kLengthOffset));
   }
-  __ Ret();
+  __ Ret(USE_DELAY_SLOT);
+  __ Move(v0, value);  // Ensure the stub returns correct value.
 
   __ bind(&transition_smi_elements);
   // Transition the array appropriately depending on the value type.
   __ ld(scratch, FieldMemOperand(value, HeapObject::kMapOffset));
   __ LoadRoot(at, Heap::kHeapNumberMapRootIndex);
   __ Branch(&non_double_value, ne, scratch, Operand(at));
 
   // Value is a double. Transition FAST_SMI_ELEMENTS ->
   // FAST_DOUBLE_ELEMENTS and complete the store.
   __ LoadTransitionedArrayMapConditional(
@@ skipping 189 matching lines @@
   Register dictionary = a5;
   DCHECK(!AreAliased(
       value, receiver, name, StoreWithVectorDescriptor::VectorRegister(),
       StoreWithVectorDescriptor::SlotRegister(), dictionary, a6, a7));
 
   __ ld(dictionary, FieldMemOperand(receiver, JSObject::kPropertiesOffset));
 
   GenerateDictionaryStore(masm, &miss, dictionary, name, value, a6, a7);
   Counters* counters = masm->isolate()->counters();
   __ IncrementCounter(counters->ic_store_normal_hit(), 1, a6, a7);
-  __ Ret();
+  __ Ret(USE_DELAY_SLOT);
+  __ Move(v0, value);  // Ensure the stub returns correct value.
 
   __ bind(&miss);
   __ IncrementCounter(counters->ic_store_normal_miss(), 1, a6, a7);
   GenerateMiss(masm);
 }
 
 
 #undef __
 
 
@@ skipping 117 matching lines @@
       break;
     default:
       UNIMPLEMENTED();
   }
   patcher.ChangeBranchCondition(branch_instr, opcode);
 }
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_TARGET_ARCH_MIPS64