Emit assembly instead of a blob for the instructions snapshot, and provide labels for the entry poi…

runtime/vm/snapshot.h

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #ifndef VM_SNAPSHOT_H_
 #define VM_SNAPSHOT_H_
 
 #include "platform/assert.h"
 #include "vm/allocation.h"
 #include "vm/bitfield.h"
 #include "vm/datastream.h"
 #include "vm/exceptions.h"
 #include "vm/globals.h"
 #include "vm/growable_array.h"
 #include "vm/isolate.h"
 #include "vm/visitor.h"
 
 namespace dart {
 
 // Forward declarations.
 class AbstractType;
 class Array;
 class Class;
 class ClassTable;
+class Code;
 class ExternalTypedData;
 class GrowableObjectArray;
 class Heap;
+class Instructions;
 class LanguageError;
 class Library;
 class Object;
 class PassiveObject;
 class ObjectStore;
 class PageSpace;
 class RawApiError;
 class RawArray;
 class RawBigint;
 class RawBoundedType;
@@ skipping 732 matching lines @@
   friend class FullSnapshotWriter;
   DISALLOW_COPY_AND_ASSIGN(ForwardList);
 };
 
 
 class InstructionsWriter : public ZoneAllocated {
  public:
   InstructionsWriter(uint8_t** buffer,
                      ReAlloc alloc,
                      intptr_t initial_size)
-    : stream_(buffer, alloc, initial_size) {
+    : stream_(buffer, alloc, initial_size),
+      next_offset_(0),
+      instructions_() {
     ASSERT(buffer != NULL);
     ASSERT(alloc != NULL);
   }
 
   // Size of the snapshot.
   intptr_t BytesWritten() const { return stream_.bytes_written(); }
 
   int32_t GetOffsetFor(RawInstructions* instructions);
 
+  void SetInstructionsCode(RawInstructions* insns, RawCode* code) {

[rmacnak, 2015/09/03 20:17:53]

Must not use the back pointer in Instructions because it goes away with the
calling convention change.

+    for (intptr_t i = 0; i < instructions_.length(); i++) {
+      if (instructions_[i].raw_insns_ == insns) {
+        instructions_[i].raw_code_ = code;
+        return;
+      }
+    }
+    UNREACHABLE();
+  }
+
+  void WriteAssembly();
+
  private:
+  struct InstructionsData {
+    explicit InstructionsData(RawInstructions* insns)
+        : raw_insns_(insns), raw_code_(NULL) { }
+
+    union {
+      RawInstructions* raw_insns_;
+      const Instructions* insns_;
+    };
+    union {
+      RawCode* raw_code_;
+      const Code* code_;
+    };
+  };
+
+
   WriteStream stream_;
+  intptr_t next_offset_;
+  GrowableArray<InstructionsData> instructions_;
 
   DISALLOW_COPY_AND_ASSIGN(InstructionsWriter);
 };
 
 
 class SnapshotWriter : public BaseWriter {
  protected:
   SnapshotWriter(Snapshot::Kind kind,
                  uint8_t** buffer,
                  ReAlloc alloc,
@@ skipping 30 matching lines @@
 
   // Write a version string for the snapshot.
   void WriteVersion();
 
   static intptr_t FirstObjectId();
 
   int32_t GetInstructionsId(RawInstructions* instructions) {
     return instructions_writer_->GetOffsetFor(instructions);
   }
 
+  void SetInstructionsCode(RawInstructions* instructions, RawCode* code) {
+    return instructions_writer_->SetInstructionsCode(instructions, code);
+  }
+
  protected:
   void UnmarkAll() {
     if (!unmarked_objects_ && forward_list_ != NULL) {
       forward_list_->UnmarkAll();
       unmarked_objects_ = true;
     }
   }
 
   bool CheckAndWritePredefinedObject(RawObject* raw);
   bool HandleVMIsolateObject(RawObject* raw);
@@ skipping 198 matching lines @@
  private:
   SnapshotWriter* writer_;
   bool as_references_;
 
   DISALLOW_COPY_AND_ASSIGN(SnapshotWriterVisitor);
 };
 
 }  // namespace dart
 
 #endif  // VM_SNAPSHOT_H_