Second set of changes for implementation of stack map support.

vm/code_descriptors.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_CODE_DESCRIPTORS_H_
+#define VM_CODE_DESCRIPTORS_H_
+
+#include "vm/globals.h"
+#include "vm/growable_array.h"
+#include "vm/object.h"
+
+namespace dart {
+
+class DescriptorList : public ZoneAllocated {
+ public:
+  struct PcDesc {
+    intptr_t pc_offset;        // PC offset value of the descriptor.
+    PcDescriptors::Kind kind;  // Descriptor kind (kDeopt, kOther).
+    intptr_t node_id;          // AST node id.
+    intptr_t token_index;      // Token position in source of PC.
+    intptr_t try_index;        // Try block index of PC.
+  };
+
+  DescriptorList() : list_() {
+  }
+  ~DescriptorList() { }
+
+  intptr_t Length() const {
+    return list_.length();
+  }
+
+  intptr_t PcOffset(int index) const {
+    return list_[index].pc_offset;
+  }
+  PcDescriptors::Kind Kind(int index) const {
+    return list_[index].kind;
+  }
+  intptr_t NodeId(int index) const {
+    return list_[index].node_id;
+  }
+  intptr_t TokenIndex(int index) const {
+    return list_[index].token_index;
+  }
+  intptr_t TryIndex(int index) const {
+    return list_[index].try_index;
+  }
+
+  void AddDescriptor(PcDescriptors::Kind kind,
+                     intptr_t pc_offset,
+                     intptr_t node_id,
+                     intptr_t token_index,
+                     intptr_t try_index);
+
+  RawPcDescriptors* FinalizePcDescriptors(uword entry_point);
+
+ private:
+  GrowableArray<struct PcDesc> list_;
+  DISALLOW_COPY_AND_ASSIGN(DescriptorList);
+};
+
+
+class StackmapBuilder : public ZoneAllocated {
+ public:
+  StackmapBuilder() :
+      builder_(new BitmapBuilder()),
+      code_(Code::ZoneHandle()),
+      stack_map_(Stackmap::ZoneHandle()),
+      list_(GrowableObjectArray::ZoneHandle(GrowableObjectArray::New())) { }
+  ~StackmapBuilder() { }
+
+  // Gets state of stack slot (object or regular value).
+  bool IsSlotObject(intptr_t stack_slot) const {
+    ASSERT(builder_ != NULL);
+    return builder_->Get(stack_slot);
+  }
+  // Sets stack slot as containing an object.
+  void SetSlotAsObject(intptr_t stack_slot) {
+    ASSERT(builder_ != NULL);
+    builder_->Set(stack_slot, true);
+  }
+  // Sets stack slot as containing regular value.
+  void SetSlotAsValue(intptr_t stack_slot) {
+    ASSERT(builder_ != NULL);
+    builder_->Set(stack_slot, false);
+  }
+  // Sets min..max (inclusive) as stack slots containing objects.
+  void SetSlotRangeAsObject(intptr_t min_stack_slot, intptr_t max_stack_slot) {
+    ASSERT(builder_ != NULL);
+    builder_->SetRange(min_stack_slot, max_stack_slot, true);
+  }
+  // Sets min..max (inclusive) as stack slots containing regular values.
+  void SetSlotRangeAsValue(intptr_t min_stack_slot, intptr_t max_stack_slot) {
+    ASSERT(builder_ != NULL);
+    builder_->SetRange(min_stack_slot, max_stack_slot, false);
+  }
+
+  void AddEntry(intptr_t pc_offset);
+
+  bool Verify();
+
+  RawArray* FinalizeStackmaps(const Code& code);
+
+ private:
+  intptr_t Length() const { return list_.Length(); }
+  RawStackmap* Map(int index) const;
+
+  BitmapBuilder* builder_;
+  Code& code_;
+  Stackmap& stack_map_;
+  GrowableObjectArray& list_;
+  DISALLOW_COPY_AND_ASSIGN(StackmapBuilder);
+};
+
+}  // namespace dart
+
+#endif  // VM_CODE_DESCRIPTORS_H_