skia/ext/skia_histogram.h

// Copyright 2016 The Chromium 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 SKIA_EXT_SKIA_HISTOGRAM_H_
#define SKIA_EXT_SKIA_HISTOGRAM_H_

#include <cstdint>

// This file exposes Chrome's histogram functionality to Skia, without bringing
// in any Chrome specific headers. To achieve the same level of optimization as
// is present in Chrome, we need to use an inlined atomic pointer. This macro
// defines a placeholder atomic which will be inlined into the call-site. This
// placeholder is passed to the actual histogram logic in Chrome.
#define SK_HISTOGRAM_POINTER_HELPER(function, ...)    \
  do {                                                \
    static intptr_t atomic_histogram_pointer = 0;     \
    function(&atomic_histogram_pointer, __VA_ARGS__); \
  } while (0)

#define SK_HISTOGRAM_BOOLEAN(name, sample) \
  SK_HISTOGRAM_POINTER_HELPER(skia::HistogramBoolean, "Skia." name, sample)

#define SK_HISTOGRAM_ENUMERATION(name, sample, boundary_value)          \
  SK_HISTOGRAM_POINTER_HELPER(skia::HistogramEnumeration, "Skia." name, \
                              sample, boundary_value)

namespace skia {

void HistogramBoolean(intptr_t* atomic_histogram_pointer,
                      const char* name,
                      bool sample);
void HistogramEnumeration(intptr_t* atomic_histogram_pointer,
                          const char* name,
                          int sample,
                          int boundary_value);

}  // namespace skia

#endif  // SKIA_EXT_SKIA_HISTOGRAM_H_