Introduce CodeSourceMap object to hold pc -> token position mappings

runtime/vm/code_descriptors.cc

 // 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.
 
 #include "vm/code_descriptors.h"
 #include "vm/compiler.h"
 
 namespace dart {
 
 void DescriptorList::AddDescriptor(RawPcDescriptors::Kind kind,
@@ skipping 23 matching lines @@
 
 
 RawPcDescriptors* DescriptorList::FinalizePcDescriptors(uword entry_point) {
   if (encoded_data_.length() == 0) {
     return Object::empty_descriptors().raw();
   }
   return PcDescriptors::New(&encoded_data_);
 }
 
 
+
+void CodeSourceMapBuilder::AddEntry(intptr_t pc_offset,
+                                    intptr_t token_pos) {
+  CodeSourceMap::EncodeInteger(&encoded_data_, pc_offset - prev_pc_offset);
+  CodeSourceMap::EncodeInteger(&encoded_data_, token_pos - prev_token_pos);
+
+  prev_pc_offset = pc_offset;
+  prev_token_pos = token_pos;
+}
+
+
+RawCodeSourceMap* CodeSourceMapBuilder::Finalize() {
+  return CodeSourceMap::New(&encoded_data_);
+}
+
+
 void StackmapTableBuilder::AddEntry(intptr_t pc_offset,
                                     BitmapBuilder* bitmap,
                                     intptr_t register_bit_count) {
   stack_map_ = Stackmap::New(pc_offset, bitmap, register_bit_count);
   list_.Add(stack_map_, Heap::kOld);
 }
 
 
 bool StackmapTableBuilder::Verify() {
   intptr_t num_entries = Length();
@@ skipping 59 matching lines @@
                               list_[i].needs_stacktrace,
                               has_catch_all);
       handlers.SetHandledTypes(i, *list_[i].handler_types);
     }
   }
   return handlers.raw();
 }
 
 
 }  // namespace dart