Zero tail stack buffers.
MSAN and the no-SIMD bots have noticed the top lanes of the tail vectors are not initialized.
As they were written it was faster to leave them unintialized, but as re-written here it's equal speed and now safe.
CQ_INCLUDE_TRYBOTS=master.client.skia:Perf-Ubuntu-Clang-GCE-CPU-AVX2-x86_64-Debug-MSAN-Trybot,Test-Ubuntu-GCC-GCE-CPU-AVX2-x86_64-Release-SKNX_NO_SIMD-Trybot
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=3790
Change-Id: Icd41ba14ae6baf9947eb361a366f1ce19ad8aa67
Reviewed-on: https://skia-review.googlesource.com/3790
Reviewed-by: Mike Klein <mtklein@chromium.org>
Commit-Queue: Mike Klein <mtklein@chromium.org>
diff --git a/src/opts/SkRasterPipeline_opts.h b/src/opts/SkRasterPipeline_opts.h
index 0759229..f072f84 100644
--- a/src/opts/SkRasterPipeline_opts.h
+++ b/src/opts/SkRasterPipeline_opts.h
@@ -166,8 +166,8 @@
SI SkNx<N,T> load(size_t tail, const T* src) {
SkASSERT(kIsTail == (tail > 0));
// TODO: maskload for 32- and 64-bit T
- T buf[8];
if (kIsTail) {
+ T buf[8] = {0};
switch (tail & (N-1)) {
case 7: buf[6] = src[6];
case 6: buf[5] = src[5];
@@ -177,7 +177,7 @@
case 2: buf[1] = src[1];
}
buf[0] = src[0];
- src = buf;
+ return SkNx<N,T>::Load(buf);
}
return SkNx<N,T>::Load(src);
}
@@ -298,8 +298,9 @@
STAGE(load_d_f16, true) {
auto ptr = (const uint64_t*)ctx + x;
- uint64_t buf[8];
+ SkNh rh, gh, bh, ah;
if (kIsTail) {
+ uint64_t buf[8] = {0};
switch (tail & (N-1)) {
case 7: buf[6] = ptr[6];
case 6: buf[5] = ptr[5];
@@ -309,11 +310,11 @@
case 2: buf[1] = ptr[1];
}
buf[0] = ptr[0];
- ptr = buf;
+ SkNh::Load4(buf, &rh, &gh, &bh, &ah);
+ } else {
+ SkNh::Load4(ptr, &rh, &gh, &bh, &ah);
}
- SkNh rh, gh, bh, ah;
- SkNh::Load4(ptr, &rh, &gh, &bh, &ah);
dr = SkHalfToFloat_finite_ftz(rh);
dg = SkHalfToFloat_finite_ftz(gh);
db = SkHalfToFloat_finite_ftz(bh);
@@ -323,8 +324,9 @@
STAGE(load_s_f16, true) {
auto ptr = (const uint64_t*)ctx + x;
- uint64_t buf[8];
+ SkNh rh, gh, bh, ah;
if (kIsTail) {
+ uint64_t buf[8] = {0};
switch (tail & (N-1)) {
case 7: buf[6] = ptr[6];
case 6: buf[5] = ptr[5];
@@ -334,11 +336,11 @@
case 2: buf[1] = ptr[1];
}
buf[0] = ptr[0];
- ptr = buf;
+ SkNh::Load4(buf, &rh, &gh, &bh, &ah);
+ } else {
+ SkNh::Load4(ptr, &rh, &gh, &bh, &ah);
}
- SkNh rh, gh, bh, ah;
- SkNh::Load4(ptr, &rh, &gh, &bh, &ah);
r = SkHalfToFloat_finite_ftz(rh);
g = SkHalfToFloat_finite_ftz(gh);
b = SkHalfToFloat_finite_ftz(bh);