Use internal memcpy when initializing code objects.

src/objects.cc

Index: src/objects.cc
diff --git a/src/objects.cc b/src/objects.cc
index 00d00d5ee6f01c6f63160af1a79ece38f05968a9..f330a5ebbede7037b807303cae021467e79a6fa1 100644
--- a/src/objects.cc
+++ b/src/objects.cc
@@ -8817,15 +8817,15 @@ void Code::CopyFrom(const CodeDesc& desc) {
   CHECK(relocation_info()->IsByteArray());
   CHECK(reinterpret_cast<intptr_t>(instruction_start()) ==
         reinterpret_cast<intptr_t>(this) + Code::kHeaderSize - kHeapObjectTag);
-  memmove(instruction_start(), desc.buffer, desc.instr_size);
+  CopyBytes<byte>(instruction_start(), desc.buffer, desc.instr_size);
 
   // copy reloc info
   // TODO(mstarzinger): Remove once we found the bug.
   CHECK(IsCode());
   CHECK(relocation_info()->IsByteArray());
-  memmove(relocation_start(),
-          desc.buffer + desc.buffer_size - desc.reloc_size,
-          desc.reloc_size);
+  CopyBytes<byte>(relocation_start(),
+                  desc.buffer + desc.buffer_size - desc.reloc_size,
+                  desc.reloc_size);
 
   // unbox handles and relocate
   intptr_t delta = instruction_start() - desc.buffer;