Clean up two unlaunched SSE 4.1 8888 blits.
This code was running on our bots but never in Chrome.
That's a bad state to be in.
My plan here use to be to redesign how our 8888 blits worked in SSE 4.1, mainly
for perfect correctness but also for speed, then to spread what I learned there
to SSE2, AVX+, and NEON.
I have since lost interest in changing any aspect of how our legacy 8888 blits
work. There's not much point in making them a bit or two more correct when the
math is fundamentally wrong.
This will cause many diffs in Gold, none perceptible.
BUG=skia:
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2062853002
CQ_EXTRA_TRYBOTS=client.skia:Test-Ubuntu-GCC-GCE-CPU-AVX2-x86_64-Release-SKNX_NO_SIMD-Trybot
Review-Url: https://codereview.chromium.org/2062853002
diff --git a/src/opts/SkOpts_sse41.cpp b/src/opts/SkOpts_sse41.cpp
index f0561a6..be31b56 100644
--- a/src/opts/SkOpts_sse41.cpp
+++ b/src/opts/SkOpts_sse41.cpp
@@ -12,221 +12,12 @@
#include "SkBlitRow_opts.h"
#include "SkBlend_opts.h"
-#ifndef SK_SUPPORT_LEGACY_X86_BLITS
-
-namespace sk_sse41_new {
-
-// An SSE register holding at most 64 bits of useful data in the low lanes.
-struct m64i {
- __m128i v;
- /*implicit*/ m64i(__m128i v) : v(v) {}
- operator __m128i() const { return v; }
-};
-
-// Load 4, 2, or 1 constant pixels or coverages (4x replicated).
-static __m128i next4(uint32_t val) { return _mm_set1_epi32(val); }
-static m64i next2(uint32_t val) { return _mm_set1_epi32(val); }
-static m64i next1(uint32_t val) { return _mm_set1_epi32(val); }
-
-static __m128i next4(uint8_t val) { return _mm_set1_epi8(val); }
-static m64i next2(uint8_t val) { return _mm_set1_epi8(val); }
-static m64i next1(uint8_t val) { return _mm_set1_epi8(val); }
-
-// Load 4, 2, or 1 variable pixels or coverages (4x replicated),
-// incrementing the pointer past what we read.
-static __m128i next4(const uint32_t*& ptr) {
- auto r = _mm_loadu_si128((const __m128i*)ptr);
- ptr += 4;
- return r;
-}
-static m64i next2(const uint32_t*& ptr) {
- auto r = _mm_loadl_epi64((const __m128i*)ptr);
- ptr += 2;
- return r;
-}
-static m64i next1(const uint32_t*& ptr) {
- auto r = _mm_cvtsi32_si128(*ptr);
- ptr += 1;
- return r;
-}
-
-// xyzw -> xxxx yyyy zzzz wwww
-static __m128i replicate_coverage(__m128i xyzw) {
- return _mm_shuffle_epi8(xyzw, _mm_setr_epi8(0, 0, 0, 0, 1, 1, 1, 1, 2, 2, 2, 2, 3, 3, 3, 3));
-}
-
-static __m128i next4(const uint8_t*& ptr) {
- auto r = replicate_coverage(_mm_cvtsi32_si128(*(const uint32_t*)ptr));
- ptr += 4;
- return r;
-}
-static m64i next2(const uint8_t*& ptr) {
- auto r = replicate_coverage(_mm_cvtsi32_si128(*(const uint16_t*)ptr));
- ptr += 2;
- return r;
-}
-static m64i next1(const uint8_t*& ptr) {
- auto r = replicate_coverage(_mm_cvtsi32_si128(*ptr));
- ptr += 1;
- return r;
-}
-
-// For i = 0...n, tgt = fn(dst,src,cov), where Dst,Src,and Cov can be constants or arrays.
-template <typename Dst, typename Src, typename Cov, typename Fn>
-static void loop(int n, uint32_t* t, const Dst dst, const Src src, const Cov cov, Fn&& fn) {
- // We don't want to muck with the callers' pointers, so we make them const and copy here.
- Dst d = dst;
- Src s = src;
- Cov c = cov;
-
- // Writing this as a single while-loop helps hoist loop invariants from fn.
- while (n) {
- if (n >= 4) {
- _mm_storeu_si128((__m128i*)t, fn(next4(d), next4(s), next4(c)));
- t += 4;
- n -= 4;
- continue;
- }
- if (n & 2) {
- _mm_storel_epi64((__m128i*)t, fn(next2(d), next2(s), next2(c)));
- t += 2;
- }
- if (n & 1) {
- *t = _mm_cvtsi128_si32(fn(next1(d), next1(s), next1(c)));
- }
- return;
- }
-}
-
-// packed
-// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ //
-// unpacked
-
-// Everything on the packed side of the squiggly line deals with densely packed 8-bit data,
-// e.g. [BGRA bgra ... ] for pixels or [ CCCC cccc ... ] for coverage.
-//
-// Everything on the unpacked side of the squiggly line deals with unpacked 8-bit data,
-// e.g [B_G_ R_A_ b_g_ r_a_ ] for pixels or [ C_C_ C_C_ c_c_ c_c_ c_c_ ] for coverage,
-// where _ is a zero byte.
-//
-// Adapt<Fn> / adapt(fn) allow the two sides to interoperate,
-// by unpacking arguments, calling fn, then packing the results.
-//
-// This lets us write most of our code in terms of unpacked inputs (considerably simpler)
-// and all the packing and unpacking is handled automatically.
-
-template <typename Fn>
-struct Adapt {
- Fn fn;
-
- __m128i operator()(__m128i d, __m128i s, __m128i c) {
- auto lo = [](__m128i x) { return _mm_unpacklo_epi8(x, _mm_setzero_si128()); };
- auto hi = [](__m128i x) { return _mm_unpackhi_epi8(x, _mm_setzero_si128()); };
- return _mm_packus_epi16(fn(lo(d), lo(s), lo(c)),
- fn(hi(d), hi(s), hi(c)));
- }
-
- m64i operator()(const m64i& d, const m64i& s, const m64i& c) {
- auto lo = [](__m128i x) { return _mm_unpacklo_epi8(x, _mm_setzero_si128()); };
- auto r = fn(lo(d), lo(s), lo(c));
- return _mm_packus_epi16(r, r);
- }
-};
-
-template <typename Fn>
-static Adapt<Fn> adapt(Fn&& fn) { return { fn }; }
-
-// These helpers all work exclusively with unpacked 8-bit values,
-// except div255() with is 16-bit -> unpacked 8-bit, and mul255() which is the reverse.
-
-// Divide by 255 with rounding.
-// (x+127)/255 == ((x+128)*257)>>16.
-// Sometimes we can be more efficient by breaking this into two parts.
-static __m128i div255_part1(__m128i x) { return _mm_add_epi16(x, _mm_set1_epi16(128)); }
-static __m128i div255_part2(__m128i x) { return _mm_mulhi_epu16(x, _mm_set1_epi16(257)); }
-static __m128i div255(__m128i x) { return div255_part2(div255_part1(x)); }
-
-// (x*y+127)/255, a byte multiply.
-static __m128i scale(__m128i x, __m128i y) { return div255(_mm_mullo_epi16(x, y)); }
-
-// (255 * x).
-static __m128i mul255(__m128i x) { return _mm_sub_epi16(_mm_slli_epi16(x, 8), x); }
-
-// (255 - x).
-static __m128i inv(__m128i x) { return _mm_xor_si128(_mm_set1_epi16(0x00ff), x); }
-
-// ARGB argb -> AAAA aaaa
-static __m128i alphas(__m128i px) {
- const int a = 2 * (SK_A32_SHIFT/8); // SK_A32_SHIFT is typically 24, so this is typically 6.
- const int _ = ~0;
- return _mm_shuffle_epi8(px, _mm_setr_epi8(a+0,_,a+0,_,a+0,_,a+0,_, a+8,_,a+8,_,a+8,_,a+8,_));
-}
-
-// SrcOver, with a constant source and full coverage.
-static void blit_row_color32(SkPMColor* tgt, const SkPMColor* dst, int n, SkPMColor src) {
- // We want to calculate s + (d * inv(alphas(s)) + 127)/255.
- // We'd generally do that div255 as s + ((d * inv(alphas(s)) + 128)*257)>>16.
-
- // But we can go one step further to ((s*255 + 128 + d*inv(alphas(s)))*257)>>16.
- // This lets us hoist (s*255+128) and inv(alphas(s)) out of the loop.
- __m128i s = _mm_unpacklo_epi8(_mm_set1_epi32(src), _mm_setzero_si128()),
- s_255_128 = div255_part1(mul255(s)),
- A = inv(alphas(s));
-
- const uint8_t cov = 0xff;
- loop(n, tgt, dst, src, cov, adapt([=](__m128i d, __m128i, __m128i) {
- return div255_part2(_mm_add_epi16(s_255_128, _mm_mullo_epi16(d, A)));
- }));
-}
-
-// SrcOver, with a constant source and variable coverage.
-// If the source is opaque, SrcOver becomes Src.
-static void blit_mask_d32_a8(SkPMColor* dst, size_t dstRB,
- const SkAlpha* cov, size_t covRB,
- SkColor color, int w, int h) {
- if (SkColorGetA(color) == 0xFF) {
- const SkPMColor src = SkSwizzle_BGRA_to_PMColor(color);
- while (h --> 0) {
- loop(w, dst, (const SkPMColor*)dst, src, cov,
- adapt([](__m128i d, __m128i s, __m128i c) {
- // Src blend mode: a simple lerp from d to s by c.
- // TODO: try a pmaddubsw version?
- return div255(_mm_add_epi16(_mm_mullo_epi16(inv(c),d),
- _mm_mullo_epi16( c ,s)));
- }));
- dst += dstRB / sizeof(*dst);
- cov += covRB / sizeof(*cov);
- }
- } else {
- const SkPMColor src = SkPreMultiplyColor(color);
- while (h --> 0) {
- loop(w, dst, (const SkPMColor*)dst, src, cov,
- adapt([](__m128i d, __m128i s, __m128i c) {
- // SrcOver blend mode, with coverage folded into source alpha.
- __m128i sc = scale(s,c),
- AC = inv(alphas(sc));
- return _mm_add_epi16(sc, scale(d,AC));
- }));
- dst += dstRB / sizeof(*dst);
- cov += covRB / sizeof(*cov);
- }
- }
-}
-} // namespace sk_sse41_new
-
-#endif
-
namespace SkOpts {
void Init_sse41() {
- box_blur_xx = sk_sse41::box_blur_xx;
- box_blur_xy = sk_sse41::box_blur_xy;
- box_blur_yx = sk_sse41::box_blur_yx;
- srcover_srgb_srgb = sk_sse41::srcover_srgb_srgb;
-
- #ifndef SK_SUPPORT_LEGACY_X86_BLITS
- blit_row_color32 = sk_sse41_new::blit_row_color32;
- blit_mask_d32_a8 = sk_sse41_new::blit_mask_d32_a8;
- #endif
+ box_blur_xx = sk_sse41::box_blur_xx;
+ box_blur_xy = sk_sse41::box_blur_xy;
+ box_blur_yx = sk_sse41::box_blur_yx;
+ srcover_srgb_srgb = sk_sse41::srcover_srgb_srgb;
blit_row_s32a_opaque = sk_sse41::blit_row_s32a_opaque;
}
}