[wasm] Fix bounds check for zero initial memory.

src/s390/assembler-s390.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 215 matching lines @@
   DCHECK(IsWasmMemorySizeReference(rmode_));
   return static_cast<uint32_t>(
       reinterpret_cast<intptr_t>(Assembler::target_address_at(pc_, host_)));
 }
 
 Address RelocInfo::wasm_global_reference() {
   DCHECK(IsWasmGlobalReference(rmode_));
   return Assembler::target_address_at(pc_, host_);
 }
 
+uint8_t RelocInfo::wasm_memtype_size_reference() {
+  DCHECK(IsWasmMemorySizeReference(rmode_));
+  return static_cast<uint8_t>(
+      reinterpret_cast<intptr_t>(Assembler::target_address_at(pc_, host_)));
+}
+
 void RelocInfo::unchecked_update_wasm_memory_reference(
     Address address, ICacheFlushMode flush_mode) {
   Assembler::set_target_address_at(isolate_, pc_, host_, address, flush_mode);
 }
 
 void RelocInfo::unchecked_update_wasm_memory_size(uint32_t size,
                                                   ICacheFlushMode flush_mode) {
   Assembler::set_target_address_at(isolate_, pc_, host_,
                                    reinterpret_cast<Address>(size), flush_mode);
 }
@@ skipping 2882 matching lines @@
                             SKIP_ICACHE_FLUSH);
     }
 
     reloc_info_writer.Write(&rinfo);
   }
 }
 
 }  // namespace internal
 }  // namespace v8
 #endif  // V8_TARGET_ARCH_S390