diff options
Diffstat (limited to 'src/opts/SkXfermode_opts.h')
| -rw-r--r-- | src/opts/SkXfermode_opts.h | 14 |
1 files changed, 14 insertions, 0 deletions
diff --git a/src/opts/SkXfermode_opts.h b/src/opts/SkXfermode_opts.h index f15094c98b..31817f5f61 100644 --- a/src/opts/SkXfermode_opts.h +++ b/src/opts/SkXfermode_opts.h @@ -9,6 +9,7 @@ #define Sk4pxXfermode_DEFINED #include "Sk4px.h" +#include "SkMSAN.h" #include "SkNx.h" #include "SkXfermode_proccoeff.h" @@ -202,6 +203,17 @@ XFERMODE_AA(Plus) { // [ clamp( (1-AA)D + (AA)(S+D) ) == clamp(D + AA*S) ] #undef XFERMODE_AA +// Src and Clear modes are safe to use with unitialized dst buffers, +// even if the implementation branches based on bytes from dst (e.g. asserts in Debug mode). +// For those modes, just lie to MSAN that dst is always intialized. +template <typename Xfermode> static void mark_dst_initialized_if_safe(void*, void*) {} +template <> void mark_dst_initialized_if_safe<Src>(void* dst, void* end) { + sk_msan_mark_initialized(dst, end, "Src doesn't read dst."); +} +template <> void mark_dst_initialized_if_safe<Clear>(void* dst, void* end) { + sk_msan_mark_initialized(dst, end, "Clear doesn't read dst."); +} + template <typename Xfermode> class Sk4pxXfermode : public SkProcCoeffXfermode { public: @@ -209,6 +221,7 @@ public: : INHERITED(rec, mode) {} void xfer32(SkPMColor dst[], const SkPMColor src[], int n, const SkAlpha aa[]) const override { + mark_dst_initialized_if_safe<Xfermode>(dst, dst+n); if (nullptr == aa) { Sk4px::MapDstSrc(n, dst, src, Xfermode()); } else { @@ -217,6 +230,7 @@ public: } void xfer16(uint16_t dst[], const SkPMColor src[], int n, const SkAlpha aa[]) const override { + mark_dst_initialized_if_safe<Xfermode>(dst, dst+n); SkPMColor dst32[4]; while (n >= 4) { dst32[0] = SkPixel16ToPixel32(dst[0]); |