| /* |
| * 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 "bench/Benchmark.h" |
| #include "include/core/SkString.h" |
| #include "include/private/SkColorData.h" |
| #include "include/utils/SkRandom.h" |
| |
| template <bool kFast, bool kScale> |
| class FourByteInterpBench : public Benchmark { |
| public: |
| FourByteInterpBench() { |
| fName.set("four_byte_interp"); |
| fName.append(kFast ? "_fast" : "_slow"); |
| fName.append(kScale ? "_255" : "_256"); |
| } |
| |
| bool isSuitableFor(Backend backend) override { |
| return backend == kNonRendering_Backend; |
| } |
| |
| const char* onGetName() override { return fName.c_str(); } |
| |
| void onDelayedSetup() override { |
| // A handful of random srcs and dsts. |
| SkRandom rand; |
| for (int i = 0; i < kInputs; i++) { |
| fSrcs[i] = SkPreMultiplyColor(rand.nextU()); |
| fDsts[i] = SkPreMultiplyColor(rand.nextU()); |
| } |
| |
| // We'll exhaustively test all scales instead of using random numbers. |
| for (int i = 0; i <= 256; i++) { |
| fScales[i] = i; |
| } |
| if (kScale) fScales[256] = 255; // We'll just do 255 twice if we're limited to [0,255]. |
| } |
| |
| void onDraw(int loops, SkCanvas*) override { |
| // We xor results of FourByteInterp into junk to make sure the function runs. |
| volatile SkPMColor junk = 0; |
| |
| for (int loop = 0; loop < loops; loop++) { |
| for (int i = 0; i < kInputs; i++) { |
| for (size_t j = 0; j <= 256; j++) { |
| // Note: we really want to load src and dst here and not outside in the i-loop. |
| // If we put the loads there, a clever compiler will do the not-insignificant |
| // work in the FourByteInterps that depends only on src and dst outside this |
| // loop, so we'd only be benchmarking the back half of those functions that also |
| // depends on scale. Even here, these must be volatile arrays to prevent that |
| // clever compiler from hoisting the loads out of the loop on its own. |
| const SkPMColor src = fSrcs[i]; |
| const SkPMColor dst = fDsts[i]; |
| |
| const unsigned scale = fScales[j]; |
| |
| if (kFast && kScale) { |
| junk ^= SkFastFourByteInterp(src, dst, scale); |
| } else if (kFast) { |
| junk ^= SkFastFourByteInterp256(src, dst, scale); |
| } else if (kScale) { |
| junk ^= SkFourByteInterp(src, dst, scale); |
| } else { |
| junk ^= SkFourByteInterp256(src, dst, scale); |
| } |
| } |
| } |
| } |
| } |
| |
| private: |
| SkString fName; |
| static const int kInputs = 10; // Arbitrary. |
| volatile unsigned fSrcs[kInputs]; |
| volatile unsigned fDsts[kInputs]; |
| unsigned fScales[257]; // We need space for [0, 256]. |
| }; |
| |
| #define COMMA , |
| DEF_BENCH(return (new FourByteInterpBench<true COMMA true>);) |
| DEF_BENCH(return (new FourByteInterpBench<true COMMA false>);) |
| DEF_BENCH(return (new FourByteInterpBench<false COMMA true>);) |
| DEF_BENCH(return (new FourByteInterpBench<false COMMA false>);) |
| #undef COMMA |