MIPS64: Enable shorten-64-to-32 warning.

src/ic/mips64/stub-cache-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.
 
 #include "src/v8.h"
 
 #if V8_TARGET_ARCH_MIPS64
 
 #include "src/codegen.h"
 #include "src/ic/ic.h"
@@ skipping 39 matching lines @@
   // Calculate the base address of the entry.
   __ li(base_addr, Operand(key_offset));
   __ dsll(at, offset_scratch, kPointerSizeLog2);
   __ Daddu(base_addr, base_addr, at);
 
   // Check that the key in the entry matches the name.
   __ ld(at, MemOperand(base_addr, 0));
   __ Branch(&miss, ne, name, Operand(at));
 
   // Check the map matches.
-  __ ld(at, MemOperand(base_addr, map_off_addr - key_off_addr));
+  __ ld(at, MemOperand(base_addr,
+                       static_cast<int32_t>(map_off_addr - key_off_addr)));
   __ ld(scratch2, FieldMemOperand(receiver, HeapObject::kMapOffset));
   __ Branch(&miss, ne, at, Operand(scratch2));
 
   // Get the code entry from the cache.
   Register code = scratch2;
   scratch2 = no_reg;
-  __ ld(code, MemOperand(base_addr, value_off_addr - key_off_addr));
+  __ ld(code, MemOperand(base_addr,
+                         static_cast<int32_t>(value_off_addr - key_off_addr)));
 
   // Check that the flags match what we're looking for.
   Register flags_reg = base_addr;
   base_addr = no_reg;
   __ lw(flags_reg, FieldMemOperand(code, Code::kFlagsOffset));
   __ And(flags_reg, flags_reg, Operand(~Code::kFlagsNotUsedInLookup));
   __ Branch(&miss, ne, flags_reg, Operand(flags));
 
 #ifdef DEBUG
   if (FLAG_test_secondary_stub_cache && table == StubCache::kPrimary) {
@@ skipping 89 matching lines @@
   __ IncrementCounter(counters->megamorphic_stub_cache_misses(), 1, extra2,
                       extra3);
 }
 
 
 #undef __
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_TARGET_ARCH_MIPS64