bench/Sk4fBench.cpp

/*
 * Copyright 2015 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/SkColor.h"
#include "src/core/SkVx.h"

#include <array>

// Writing into this array prevents the loops from being compiled away.
static volatile float blackhole[4];

template <typename T>
struct Sk4fRoundtripBench : public Benchmark {
    Sk4fRoundtripBench() {}

    const char* onGetName() override {
        switch (sizeof(T)) {
            case 1: return "Sk4f_roundtrip_u8";
            case 2: return "Sk4f_roundtrip_u16";
            case 4: return "Sk4f_roundtrip_int";
        }
        SkASSERT(false);
        return "";
    }

    bool isSuitableFor(Backend backend) override { return backend == Backend::kNonRendering; }

    void onDraw(int loops, SkCanvas* canvas) override {
        skvx::float4 fs(1,2,3,4);
        while (loops --> 0) {
            fs = skvx::cast<float>(skvx::cast<T>(fs));
        }
        fs.store(const_cast<float*>(blackhole));
    }
};
DEF_BENCH(return new Sk4fRoundtripBench<uint8_t>;)
DEF_BENCH(return new Sk4fRoundtripBench<uint16_t>;)
DEF_BENCH(return new Sk4fRoundtripBench<int>;)

struct Sk4fFloorBench : public Benchmark {
    Sk4fFloorBench() {}

    const char* onGetName() override { return "Sk4f_floor"; }
    bool isSuitableFor(Backend backend) override { return backend == Backend::kNonRendering; }

    void onDraw(int loops, SkCanvas* canvas) override {
        skvx::float4 fs(1,2,3,4);
        while (loops --> 0) {
            fs = floor(fs);
        }
        fs.store(const_cast<float*>(blackhole));
    }
};
DEF_BENCH(return new Sk4fFloorBench;)

struct Sk4fGradientBench : public Benchmark {
    const char* onGetName() override { return "Sk4f_gradient"; }
    bool isSuitableFor(Backend backend) override { return backend == Backend::kNonRendering; }

    std::array<SkPMColor, 100> fDevice;
    void onDraw(int loops, SkCanvas*) override {
        skvx::float4 c0(0,0,255,255),
                     c1(255,0,0,255),
                     dc = c1 - c0,
                     fx(0.1f),
                     dx(0.002f),
                     dcdx(dc*dx),
                     dcdx4(dcdx+dcdx+dcdx+dcdx);

        for (int n = 0; n < loops; n++) {
            auto a = c0 + dc*fx + 0.5f,  // add an extra 0.5f to get rounding for free.
                 b = a + dcdx,
                 c = b + dcdx,
                 d = c + dcdx;
            for (size_t i = 0; i < std::size(fDevice); i += 4) {
                skvx::cast<uint8_t>(a).store(&fDevice[i + 0]);
                skvx::cast<uint8_t>(b).store(&fDevice[i + 1]);
                skvx::cast<uint8_t>(c).store(&fDevice[i + 2]);
                skvx::cast<uint8_t>(d).store(&fDevice[i + 3]);
                a = a + dcdx4;
                b = b + dcdx4;
                c = c + dcdx4;
                d = d + dcdx4;
            }
        }
    }
};
DEF_BENCH(return new Sk4fGradientBench;)