Second set of changes for implementation of stack map support.

vm/code_descriptors.cc

Index: vm/code_descriptors.cc
===================================================================
--- vm/code_descriptors.cc	(revision 0)
+++ vm/code_descriptors.cc	(revision 0)
@@ -0,0 +1,84 @@
+// 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"
+
+namespace dart {
+
+void DescriptorList::AddDescriptor(PcDescriptors::Kind kind,
+                                   intptr_t pc_offset,
+                                   intptr_t node_id,
+                                   intptr_t token_index,
+                                   intptr_t try_index) {
+  struct PcDesc data;
+  data.pc_offset = pc_offset;
+  data.kind = kind;
+  data.node_id = node_id;
+  data.token_index = token_index;
+  data.try_index = try_index;
+  list_.Add(data);
+}
+
+
+RawPcDescriptors* DescriptorList::FinalizePcDescriptors(uword entry_point) {
+  intptr_t num_descriptors = Length();
+  const PcDescriptors& descriptors =
+      PcDescriptors::Handle(PcDescriptors::New(num_descriptors));
+  for (intptr_t i = 0; i < num_descriptors; i++) {
+    descriptors.AddDescriptor(i,
+                              (entry_point + PcOffset(i)),
+                              Kind(i),
+                              NodeId(i),
+                              TokenIndex(i),
+                              TryIndex(i));
+  }
+  return descriptors.raw();
+}
+
+
+void StackmapBuilder::AddEntry(intptr_t pc_offset) {
+  stack_map_ = Stackmap::New(pc_offset, code_, builder_);
+  list_.Add(stack_map_);
+}
+
+
+bool StackmapBuilder::Verify() {
+  intptr_t num_entries = Length();
+  Stackmap& map1 = Stackmap::Handle();
+  Stackmap& map2 = Stackmap::Handle();
+  for (intptr_t i = 1; i < num_entries; i++) {
+    map1 = Map(i - 1);
+    map2 = Map(i);
+    // Ensure there are no duplicates and the entries are sorted.
+    if (map1.PC() >= map2.PC()) {
+      return false;
+    }
+  }
+  return true;
+}
+
+
+RawArray* StackmapBuilder::FinalizeStackmaps(const Code& code) {
+  ASSERT(Verify());
+  intptr_t num_entries = Length();
+  uword entry_point = code.EntryPoint();
+  if (num_entries == 0) {
+    return Array::Empty();
+  }
+  for (intptr_t i = 0; i < num_entries; i++) {
+    stack_map_ = Map(i);
+    stack_map_.SetPC(entry_point + stack_map_.PC());
+    stack_map_.SetCode(code);
+  }
+  return Array::MakeArray(list_);
+}
+
+
+RawStackmap* StackmapBuilder::Map(int index) const {
+  Stackmap& map = Stackmap::Handle();
+  map ^= list_.At(index);
+  return map.raw();
+}
+
+}  // namespace dart