[counter] Properly measure own-time of runtime counters.

src/counters.h

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef V8_COUNTERS_H_
 #define V8_COUNTERS_H_
 
 #include "include/v8.h"
 #include "src/allocation.h"
 #include "src/base/platform/elapsed-timer.h"
@@ skipping 683 matching lines @@
   SC(lo_space_bytes_used, V8.MemoryLoSpaceBytesUsed)                           \
   SC(turbo_escape_allocs_replaced, V8.TurboEscapeAllocsReplaced)               \
   SC(crankshaft_escape_allocs_replaced, V8.CrankshaftEscapeAllocsReplaced)     \
   SC(turbo_escape_loads_replaced, V8.TurboEscapeLoadsReplaced)                 \
   SC(crankshaft_escape_loads_replaced, V8.CrankshaftEscapeLoadsReplaced)       \
   /* Total code size (including metadata) of baseline code or bytecode. */     \
   SC(total_baseline_code_size, V8.TotalBaselineCodeSize)                       \
   /* Total count of functions compiled using the baseline compiler. */         \
   SC(total_baseline_compile_count, V8.TotalBaselineCompileCount)
 
+typedef struct RuntimeCallCounter {
+  int64_t count = 0;
+  base::TimeDelta time;
+  RuntimeCallCounter* parent_counter;
+
+  void Reset();
+} RuntimeCallCounter;
+
 struct RuntimeCallStats {
 #define CALL_RUNTIME_COUNTER(name, nargs, ressize) \
-  uint32_t Count_Runtime_##name;                   \
-  base::TimeDelta Time_Runtime_##name;
+  RuntimeCallCounter Runtime_##name;
   FOR_EACH_INTRINSIC(CALL_RUNTIME_COUNTER)
 #undef CALL_RUNTIME_COUNTER
-#define CALL_BUILTIN_COUNTER(name, type) \
-  uint32_t Count_Builtin_##name;         \
-  base::TimeDelta Time_Builtin_##name;
+#define CALL_BUILTIN_COUNTER(name, type) RuntimeCallCounter Builtin_##name;
   BUILTIN_LIST_C(CALL_BUILTIN_COUNTER)
 #undef CALL_BUILTIN_COUNTER
 
   // Dummy counter for the unexpected stub miss.
-  uint32_t Count_UnexpectedStubMiss;
-  base::TimeDelta Time_UnexpectedStubMiss;
+  RuntimeCallCounter UnexpectedStubMiss;
+  // Counter to track recursive time events.
+  RuntimeCallCounter* current_counter;
 
-  bool in_runtime_call = false;
+  // Starting measuring the time for a function. This will establish the
+  // connection to the parent counter for properly calculating the own times.
+  void Enter(RuntimeCallCounter* counter);
+  // Leave a scope for a measured runtime function. This will properly add
+  // the time delta to the current_counter and subtract the delta from its
+  // parent.
+  void Leave(base::TimeDelta time);
 
   void Reset();
   void Print(std::ostream& os);
 
   RuntimeCallStats() { Reset(); }
 };
 
 // This file contains all the v8 counters that are in use.
 class Counters {
  public:
@@ skipping 172 matching lines @@
 
   explicit Counters(Isolate* isolate);
 
   DISALLOW_IMPLICIT_CONSTRUCTORS(Counters);
 };
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_COUNTERS_H_