Sk4f: add floor()
BUG=skia:
GOLD_TRYBOT_URL= https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&issue=1685773002
CQ_EXTRA_TRYBOTS=client.skia:Test-Ubuntu-GCC-GCE-CPU-AVX2-x86_64-Release-SKNX_NO_SIMD-Trybot
Review URL: https://codereview.chromium.org/1685773002
diff --git a/bench/Sk4fBench.cpp b/bench/Sk4fBench.cpp
index d5201fa..a932c29 100644
--- a/bench/Sk4fBench.cpp
+++ b/bench/Sk4fBench.cpp
@@ -40,6 +40,22 @@
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 == kNonRendering_Backend; }
+
+ void onDraw(int loops, SkCanvas* canvas) override {
+ Sk4f fs(1,2,3,4);
+ while (loops --> 0) {
+ fs = fs.floor();
+ }
+ fs.store((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 == kNonRendering_Backend; }
diff --git a/src/core/SkNx.h b/src/core/SkNx.h
index 69295d4..986c133 100644
--- a/src/core/SkNx.h
+++ b/src/core/SkNx.h
@@ -50,7 +50,7 @@
#undef OP
#define OP(op) SkNx op() const { return {fLo.op(), fHi.op()}; }
- OP(abs)
+ OP(abs) OP(floor)
OP(sqrt) OP(rsqrt0) OP(rsqrt1) OP(rsqrt2)
OP(invert) OP(approxInvert)
#undef OP
@@ -124,6 +124,7 @@
static SkNx Max(const SkNx& a, const SkNx& b) { return SkTMax(a.fVal, b.fVal); }
SkNx abs() const { return SkTAbs(fVal); }
+ SkNx floor() const { return Floor(fVal); }
SkNx sqrt () const { return Sqrt(fVal); }
SkNx rsqrt0() const { return this->sqrt().invert(); }
@@ -145,6 +146,8 @@
SkNx thenElse(const SkNx& t, const SkNx& e) const { return fVal != 0 ? t : e; }
protected:
+ static double Floor(double val) { return ::floor (val); }
+ static float Floor(float val) { return ::floorf(val); }
static double Sqrt(double val) { return ::sqrt (val); }
static float Sqrt(float val) { return ::sqrtf(val); }
diff --git a/src/opts/SkNx_neon.h b/src/opts/SkNx_neon.h
index 2cb8eb3..cdc4615 100644
--- a/src/opts/SkNx_neon.h
+++ b/src/opts/SkNx_neon.h
@@ -10,6 +10,17 @@
#define SKNX_IS_FAST
+// ARMv8 has vrndmq_f32 to floor 4 floats. Here we emulate it:
+// - round by adding (1<<23) with our sign, then subtracting it;
+// - if that rounded value is bigger than our input, subtract 1.
+static inline float32x4_t armv7_vrndmq_f32(float32x4_t v) {
+ auto sign = vandq_u32((uint32x4_t)v, vdupq_n_u32(1<<31));
+ auto bias = (float32x4_t)(vorrq_u32((uint32x4_t)vdupq_n_f32(1<<23), sign));
+ auto rounded = vsubq_f32(vaddq_f32(v, bias), bias);
+ auto too_big = vcgtq_f32(rounded, v);
+ return vsubq_f32(rounded, (float32x4_t)vandq_u32(too_big, (uint32x4_t)vdupq_n_f32(1)));
+}
+
// Well, this is absurd. The shifts require compile-time constant arguments.
#define SHIFT8(op, v, bits) switch(bits) { \
@@ -161,6 +172,14 @@
static SkNx Max(const SkNx& l, const SkNx& r) { return vmaxq_f32(l.fVec, r.fVec); }
SkNx abs() const { return vabsq_f32(fVec); }
+ SkNx floor() const {
+ #if defined(SK_CPU_ARM64)
+ return vrndmq_f32(fVec);
+ #else
+ return armv7_vrndmq_f32(fVec);
+ #endif
+ }
+
SkNx rsqrt0() const { return vrsqrteq_f32(fVec); }
SkNx rsqrt1() const {
diff --git a/src/opts/SkNx_sse.h b/src/opts/SkNx_sse.h
index 889253b..def7ba1 100644
--- a/src/opts/SkNx_sse.h
+++ b/src/opts/SkNx_sse.h
@@ -13,6 +13,17 @@
#define SKNX_IS_FAST
+// SSE 4.1 has _mm_floor_ps to floor 4 floats. We emulate it:
+// - round by adding (1<<23) with our sign, then subtracting it;
+// - if that rounded value is bigger than our input, subtract 1.
+static inline __m128 sse2_mm_floor_ps(__m128 v) {
+ __m128 sign = _mm_and_ps(v, _mm_set1_ps(-0.0f));
+ __m128 bias = _mm_or_ps(sign, _mm_set1_ps(1<<23));
+ __m128 rounded = _mm_sub_ps(_mm_add_ps(v, bias), bias);
+ __m128 too_big = _mm_cmpgt_ps(rounded, v);
+ return _mm_sub_ps(rounded, _mm_and_ps(too_big, _mm_set1_ps(1.0f)));
+}
+
template <>
class SkNx<2, float> {
public:
@@ -92,6 +103,7 @@
static SkNx Max(const SkNx& l, const SkNx& r) { return _mm_max_ps(l.fVec, r.fVec); }
SkNx abs() const { return _mm_andnot_ps(_mm_set1_ps(-0.0f), fVec); }
+ SkNx floor() const { return sse2_mm_floor_ps(fVec); }
SkNx sqrt () const { return _mm_sqrt_ps (fVec); }
SkNx rsqrt0() const { return _mm_rsqrt_ps(fVec); }
diff --git a/tests/SkNxTest.cpp b/tests/SkNxTest.cpp
index 13e0a9f..e329e17 100644
--- a/tests/SkNxTest.cpp
+++ b/tests/SkNxTest.cpp
@@ -215,6 +215,14 @@
REPORTER_ASSERT(r, fs.kth<3>() == 4.0f);
}
+DEF_TEST(SkNx_floor, r) {
+ auto fs = Sk4f(0.4f, -0.4f, 0.6f, -0.6f).floor();
+ REPORTER_ASSERT(r, fs.kth<0>() == 0.0f);
+ REPORTER_ASSERT(r, fs.kth<1>() == -1.0f);
+ REPORTER_ASSERT(r, fs.kth<2>() == 0.0f);
+ REPORTER_ASSERT(r, fs.kth<3>() == -1.0f);
+}
+
DEF_TEST(SkNx_shuffle, r) {
Sk4f f4(0,10,20,30);