skia2/bench/Sk4fBench.cpp
mtklein 6f37b4a475 Unify some SkNx code
- one base case and one N=1 case instead of two each (or three with doubles)
 - use SkNx_cast instead of FromBytes/toBytes
 - 4-at-a-time Sk4f::ToBytes becomes a special standalone Sk4f_ToBytes

If I did everything right, this'll be perf- and pixel- neutral.

https://gold.skia.org/search2?issue=1526523003&unt=true&query=source_type%3Dgm&master=false

BUG=skia:
CQ_EXTRA_TRYBOTS=client.skia:Test-Ubuntu-GCC-GCE-CPU-AVX2-x86_64-Release-SKNX_NO_SIMD-Trybot

Review URL: https://codereview.chromium.org/1526523003
2015-12-14 11:25:18 -08:00

75 lines
2.3 KiB
C++

/*
* 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 "Benchmark.h"
#include "SkColor.h"
#include "SkNx.h"
// Used to prevent the compiler from optimizing away the whole loop.
volatile uint32_t blackhole = 0;
// Not a great random number generator, but it's very fast.
// The code we're measuring is quite fast, so low overhead is essential.
static uint32_t lcg_rand(uint32_t* seed) {
*seed *= 1664525;
*seed += 1013904223;
return *seed;
}
struct Sk4fBytesRoundtripBench : public Benchmark {
Sk4fBytesRoundtripBench() {}
const char* onGetName() override { return "Sk4f_roundtrip"; }
bool isSuitableFor(Backend backend) override { return backend == kNonRendering_Backend; }
void onDraw(int loops, SkCanvas* canvas) override {
// Unlike blackhole, junk can and probably will be a register.
uint32_t junk = 0;
uint32_t seed = 0;
for (int i = 0; i < loops; i++) {
uint32_t color = lcg_rand(&seed),
back;
auto f = SkNx_cast<float>(Sk4b::Load((const uint8_t*)&color));
SkNx_cast<uint8_t>(f).store((uint8_t*)&back);
junk ^= back;
}
blackhole ^= junk;
}
};
DEF_BENCH(return new Sk4fBytesRoundtripBench;)
struct Sk4fGradientBench : public Benchmark {
const char* onGetName() override { return "Sk4f_gradient"; }
bool isSuitableFor(Backend backend) override { return backend == kNonRendering_Backend; }
SkPMColor fDevice[100];
void onDraw(int loops, SkCanvas*) override {
Sk4f 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++) {
Sk4f a = c0 + dc*fx + Sk4f(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 < SK_ARRAY_COUNT(fDevice); i += 4) {
Sk4f_ToBytes((uint8_t*)(fDevice+i), a, b, c, d);
a = a + dcdx4;
b = b + dcdx4;
c = c + dcdx4;
d = d + dcdx4;
}
}
}
};
DEF_BENCH(return new Sk4fGradientBench;)