PATCH (not to be comitted): Support for printing instruction statistics

runtime/vm/code_statistics.h

Index: runtime/vm/code_statistics.h
diff --git a/runtime/vm/code_statistics.h b/runtime/vm/code_statistics.h
new file mode 100644
index 0000000000000000000000000000000000000000..d28217bb680400b6bb09b2c456e8a4ff82872d91
--- /dev/null
+++ b/runtime/vm/code_statistics.h
@@ -0,0 +1,107 @@
+// Copyright (c) 2015, 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_STATISTICS_H_
+#define VM_CODE_STATISTICS_H_
+
+#include "vm/object.h"
+#include "vm/assembler.h"
+#include "vm/intermediate_language.h"
+
+namespace dart {
+
+class CombinedCodeStatistics {
+ public:
+  enum EntryCounter {
+#define DO(type) kTag##type,
+FOR_EACH_INSTRUCTION(DO)
+#undef DO
+
+    kPolymorphicInstanceCallAsStaticCall,
+
+    kTagCheckedSmiSlowPath,
+    kTagCheckedSmiCmpSlowPath,
+    kTagBoxAllocationSlowPath,
+    kTagAllocateContextSlowPath,
+    kTagCheckStackOverflowSlowPath,
+    kTagMegamorphicSlowPath,
+
+    kTagCheckArgumentCount,
+    kTagCopyParameters,
+    kTagStubCode,
+    kTagCheckedEntry,
+    kTagFrameEntry,
+    kTagLoadClosureContext,
+    kTagIntrinsics,
+    kDebugAfterBody,
+
+    kTagTrySyncSpilling,
+
+    kNumEntries,
+  };
+
+  CombinedCodeStatistics();
+
+  void Begin(Instruction* instruction);
+  void End(Instruction* instruction);
+
+  void DumpStatistics();
+
+ private:
+  friend class CodeStatistics;
+
+  void SlowSort();
+  void Swap(intptr_t a, intptr_t b);
+
+  typedef struct {
+    const char* name;
+    intptr_t bytes;
+    intptr_t count;
+  } Entry;
+
+  Entry entries_[kNumEntries];
+  intptr_t unaccounted_bytes_;
+  intptr_t alignment_bytes_;
+  intptr_t object_header_bytes_;
+  intptr_t wasteful_function_count_;
+  intptr_t return_const_count_;
+  intptr_t return_const_with_load_field_count_;
+};
+
+class CodeStatistics {
+ public:
+  explicit CodeStatistics(Assembler* assembler);
+
+  void Begin(Instruction* instruction);
+  void End(Instruction* instruction);
+
+  void SpecialBegin(intptr_t tag);
+  void SpecialEnd(intptr_t tag);
+
+  void AppendTo(CombinedCodeStatistics* stat);
+
+  void Finalize();
+
+ private:
+  static const int kStackSize = 8;
+
+  Assembler* assembler_;
+
+  typedef struct {
+    intptr_t bytes;
+    intptr_t count;
+  } Entry;
+
+  Entry entries_[CombinedCodeStatistics::kNumEntries];
+  intptr_t instruction_bytes_;
+  intptr_t unaccounted_bytes_;
+  intptr_t alignment_bytes_;
+
+  intptr_t stack_[kStackSize];
+  intptr_t stack_index_;
+};
+
+}  // namespace dart
+
+#endif  // VM_CODE_STATISTICS_H_