[wasm] Fix bounds check for zero initial memory.

src/x87/assembler-x87.cc

 // Copyright (c) 1994-2006 Sun Microsystems Inc.
 // 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.
 //
@@ skipping 98 matching lines @@
 Address RelocInfo::wasm_global_reference() {
   DCHECK(IsWasmGlobalReference(rmode_));
   return Memory::Address_at(pc_);
 }
 
 uint32_t RelocInfo::wasm_memory_size_reference() {
   DCHECK(IsWasmMemorySizeReference(rmode_));
   return Memory::uint32_at(pc_);
 }
 
+uint8 RelocInfo::wasm_memtype_size_reference() {
+  DCHECK(IsWasmMemtypeSizeReference(rmode_));
+  return Memory::uint8_at(pc_);
+}
+
 void RelocInfo::unchecked_update_wasm_memory_reference(
     Address address, ICacheFlushMode flush_mode) {
   Memory::Address_at(pc_) = address;
 }
 
 void RelocInfo::unchecked_update_wasm_memory_size(uint32_t size,
                                                   ICacheFlushMode flush_mode) {
   Memory::uint32_at(pc_) = size;
 }
 
@@ skipping 2067 matching lines @@
       return;
   }
   RelocInfo rinfo(isolate(), pc_, rmode, data, NULL);
   reloc_info_writer.Write(&rinfo);
 }
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_TARGET_ARCH_X87