iter_iter_initializer_list.rar_The Program

/* * Copyright 2013 Google Inc. * * Use of this source code is governed by a BSD-style license that can be * found in the LICENSE file. */ #include "Benchmark.h" #include "SkCanvas.h" #include "SkFontHost.h" #include "SkPaint.h" #include "SkString.h" #include "SkTemplates.h" #include "gUniqueGlyphIDs.h" #define gUniqueGlyphIDs_Sentinel 0xFFFF static int count_glyphs(const uint16_t start[]) { const uint16_t* curr = start; while (*curr != gUniqueGlyphIDs_Sentinel) { curr += 1; } return static_cast<int>(curr - start); } class FontCacheBench : public Benchmark { public: FontCacheBench() {} protected: virtual const char* onGetName() SK_OVERRIDE { return "fontcache"; } virtual void onDraw(const int loops, SkCanvas* canvas) SK_OVERRIDE { SkPaint paint; this->setupPaint(&paint); paint.setTextEncoding(SkPaint::kGlyphID_TextEncoding); const uint16_t* array = gUniqueGlyphIDs; while (*array != gUniqueGlyphIDs_Sentinel) { int count = count_glyphs(array); for (int i = 0; i < loops; ++i) { paint.measureText(array, count * sizeof(uint16_t)); } array += count + 1; // skip the sentinel } } private: typedef Benchmark INHERITED; }; /////////////////////////////////////////////////////////////////////////////// static uint32_t rotr(uint32_t value, unsigned bits) { return (value >> bits) | (value << (32 - bits)); } typedef uint32_t (*HasherProc)(uint32_t); static uint32_t hasher0(uint32_t value) { value = value ^ (value >> 16); return value ^ (value >> 8); } static uint32_t hasher2(uint32_t h) { h ^= h >> 16; h *= 0x85ebca6b; h ^= h >> 13; h *= 0xc2b2ae35; h ^= h >> 16; h ^= (h >> 8); return h; } static const struct { const char* fName; HasherProc fHasher; } gRec[] = { { "hasher0", hasher0 }, { "hasher2", hasher2 }, }; #define kMaxHashBits 12 #define kMaxHashCount (1 << kMaxHashBits) static int count_collisions(const uint16_t array[], int count, HasherProc proc, unsigned hashMask) { char table[kMaxHashCount]; sk_bzero(table, sizeof(table)); int collisions = 0; for (int i = 0; i < count; ++i) { int index = proc(array[i]) & hashMask; collisions += table[index]; table[index] = 1; } return collisions; } static void dump_array(const uint16_t array[], int count) { for (int i = 0; i < count; ++i) { SkDebugf(" %d,", array[i]); } SkDebugf("\n"); } class FontCacheEfficiency : public Benchmark { public: FontCacheEfficiency() { if (false) dump_array(NULL, 0); if (false) rotr(0, 0); } protected: virtual const char* onGetName() SK_OVERRIDE { return "fontefficiency"; } virtual void onDraw(const int loops, SkCanvas* canvas) SK_OVERRIDE { static bool gDone; if (gDone) { return; } gDone = true; for (int hashBits = 6; hashBits <= 12; hashBits += 1) { int hashMask = ((1 << hashBits) - 1); for (int limit = 32; limit <= 1024; limit <<= 1) { for (size_t i = 0; i < SK_ARRAY_COUNT(gRec); ++i) { int collisions = 0; int glyphs = 0; const uint16_t* array = gUniqueGlyphIDs; while (*array != gUniqueGlyphIDs_Sentinel) { int count = SkMin32(count_glyphs(array), limit); collisions += count_collisions(array, count, gRec[i].fHasher, hashMask); glyphs += count; array += count + 1; // skip the sentinel } SkDebugf("hashBits [%d] limit [%d] collisions [%d / %d = %1.2g%%] using %s\n", hashBits, limit, collisions, glyphs, collisions * 100.0 / glyphs, gRec[i].fName); } } } } private: typedef Benchmark INHERITED; }; /////////////////////////////////////////////////////////////////////////////// DEF_BENCH( return new FontCacheBench(); ) // undefine this to run the efficiency test //DEF_BENCH( return new FontCacheEfficiency(); )