A64: Synchronize with r17525.

src/serialize.cc

Index: src/serialize.cc
diff --git a/src/serialize.cc b/src/serialize.cc
index 7ed36665e2fa3ea7c917f552626788cc4d4da54f..3cc7053c7fffc88750640f73b83f3119fd41d397 100644
--- a/src/serialize.cc
+++ b/src/serialize.cc
@@ -1668,12 +1668,12 @@ void Serializer::ObjectSerializer::VisitPointers(Object** start,
 
 
 void Serializer::ObjectSerializer::VisitEmbeddedPointer(RelocInfo* rinfo) {
-  Object** current = rinfo->target_object_address();
+  Object* current = rinfo->target_object();
 
   int skip = OutputRawData(rinfo->target_address_address(),
                            kCanReturnSkipInsteadOfSkipping);
   HowToCode representation = rinfo->IsCodedSpecially() ? kFromCode : kPlain;
-  serializer_->SerializeObject(*current, representation, kStartOfObject, skip);
+  serializer_->SerializeObject(current, representation, kStartOfObject, skip);
   bytes_processed_so_far_ += rinfo->target_address_size();
 }
 
@@ -1694,12 +1694,12 @@ void Serializer::ObjectSerializer::VisitExternalReference(RelocInfo* rinfo) {
   Address references_start = rinfo->target_address_address();
   int skip = OutputRawData(references_start, kCanReturnSkipInsteadOfSkipping);
 
-  Address* current = rinfo->target_reference_address();
+  Address current = rinfo->target_reference();
   int representation = rinfo->IsCodedSpecially() ?
                        kFromCode + kStartOfObject : kPlain + kStartOfObject;
   sink_->Put(kExternalReference + representation, "ExternalRef");
   sink_->PutInt(skip, "SkipB4ExternalRef");
-  int reference_id = serializer_->EncodeExternalReference(*current);
+  int reference_id = serializer_->EncodeExternalReference(current);
   sink_->PutInt(reference_id, "reference id");
   bytes_processed_so_far_ += rinfo->target_address_size();
 }
@@ -1776,10 +1776,29 @@ void Serializer::ObjectSerializer::VisitExternalAsciiString(
 }
 
 
+static Code* CloneCodeObject(HeapObject* code) {
+  Address copy = new byte[code->Size()];
+  OS::MemCopy(copy, code->address(), code->Size());
+  return Code::cast(HeapObject::FromAddress(copy));
+}
+
+
+static void WipeOutRelocations(Code* code) {
+  int mode_mask =
+      RelocInfo::kCodeTargetMask |
+      RelocInfo::ModeMask(RelocInfo::EMBEDDED_OBJECT) |
+      RelocInfo::ModeMask(RelocInfo::EXTERNAL_REFERENCE) |
+      RelocInfo::ModeMask(RelocInfo::RUNTIME_ENTRY);
+  for (RelocIterator it(code, mode_mask); !it.done(); it.next()) {
+    it.rinfo()->WipeOut();
+  }
+}
+
+
 int Serializer::ObjectSerializer::OutputRawData(
     Address up_to, Serializer::ObjectSerializer::ReturnSkip return_skip) {
   Address object_start = object_->address();
-  Address base = object_start + bytes_processed_so_far_;
+  int base = bytes_processed_so_far_;
   int up_to_offset = static_cast<int>(up_to - object_start);
   int to_skip = up_to_offset - bytes_processed_so_far_;
   int bytes_to_output = to_skip;
@@ -1809,10 +1828,22 @@ int Serializer::ObjectSerializer::OutputRawData(
       sink_->Put(kRawData, "RawData");
       sink_->PutInt(bytes_to_output, "length");
     }
+
+    // To make snapshots reproducible, we need to wipe out all pointers in code.
+    if (code_object_) {
+      Code* code = CloneCodeObject(object_);
+      WipeOutRelocations(code);
+      // We need to wipe out the header fields *after* wiping out the
+      // relocations, because some of these fields are needed for the latter.
+      code->WipeOutHeader();
+      object_start = code->address();
+    }
+
+    const char* description = code_object_ ? "Code" : "Byte";
     for (int i = 0; i < bytes_to_output; i++) {
-      unsigned int data = base[i];
-      sink_->PutSection(data, "Byte");
+      sink_->PutSection(object_start[base + i], description);
     }
+    if (code_object_) delete[] object_start;
   }
   if (to_skip != 0 && return_skip == kIgnoringReturn) {
     sink_->Put(kSkip, "Skip");