Frank Barchard a84bf45a21 [libyuv] Fix MSan uninitialized errors in AVX512 alpha and scale rows
Clang MemorySanitizer builds define LIBYUV_ENABLE_ROWWIN and compile
row_win.cc and scale_win.cc instead of inline assembly. Two AVX-512
intrinsic patterns in those files are not modeled by LLVM MSan:

1. _mm512_mask_cvtepi32_storeu_epi8 and _mm512_mask_cvtepi64_storeu_epi8
   lower to @llvm.x86.avx512.mask.pmov.db.mem.512 and
   @llvm.x86.avx512.mask.pmov.qb.mem.512, which LLVM MSan handles as
   unknown intrinsics without unpoisoning destination shadow memory.
   Replace them in ARGBExtractAlphaRow_AVX512BW, ScaleAddCols1_AVX512BW,
   and ScaleAddCols2_AVX512BW with _mm512_cvtepi32_epi8 /
   _mm512_cvtepi64_epi8 followed by _mm_mask_storeu_epi8, which lowers
   to @llvm.masked.store and still compiles to a single vpmovdb/vpmovqb
   instruction.

2. ARGBCopyYToAlphaRow_AVX512BW loaded dst and blended the alpha channel
   using _mm512_ternarylogic_epi32, which LLVM MSan does not model
   bitwise and flags when any destination byte (such as the old alpha
   channel) is uninitialized. Replace the load + vpternlogd + store in
   both row_win.cc and row_gcc.cc with byte-masked stores
   (_mm512_mask_storeu_epi8 / vmovdqu8 with mask 0x8888888888888888)
   that write only the alpha bytes without reading dst.

Expand ARGBCopyAlpha, ARGBExtractAlpha, and ARGBCopyYToAlpha unit tests
into _Any, _Unaligned, _Invert, and _Opt variants and poison destination
buffers under MSan to catch unmodeled masked stores. Document MSan
AVX-512 intrinsic guidelines in GEMINI.md.

Test: out/msan/libyuv_unittest --gtest_filter=*Alpha*:*ScalePlaneBox_Any*
Bug: 578615529
Change-Id: I54ac4a5844aca6cfe3aa3445fa04b8221c610b35
Reviewed-on: https://chromium-review.googlesource.com/c/libyuv/libyuv/+/8672001
Commit-Queue: Frank Barchard <fbarchard@google.com>
Reviewed-by: Dale Curtis <dalecurtis@chromium.org>
2026-10-27 16:27:29 -07:00
build_overrides [vpython] Migrate .vpython3 to vpython.toml 2026-09-18 00:28:26 -07:00
docs [libyuv] Add Qualcomm Hexagon HVX SIMD support 2026-10-19 14:16:18 -07:00
include [libyuv] Fix HAS_ macros for MergeRGBRow, HalfFloatRow 2026-10-27 13:13:51 -07:00
infra/config Use default xcode version in libyuv 2025-11-24 07:54:14 -08:00
riscv_script [libyuv] Fix RISC-V CMake/GN/Bazel builds and C compiler driver linking 2026-09-28 10:59:30 -07:00
source [libyuv] Fix MSan uninitialized errors in AVX512 alpha and scale rows 2026-10-27 16:27:29 -07:00
tools_libyuv Remove libyuv dependency on base/ 2025-01-08 09:04:21 -08:00
unit_test [libyuv] Fix MSan uninitialized errors in AVX512 alpha and scale rows 2026-10-27 16:27:29 -07:00
util [libyuv] Optimize SsimWindowRow with SIMD and use compare_win on x86 2026-10-20 15:00:52 -07:00
.clang-format clang-format libyuv 2016-11-07 17:37:23 -08:00
.gitignore DetilePlane and unittest for NEON 2022-01-31 20:05:55 +00:00
.gn [build] Use hermetic python3 for script_executable in .gn 2026-09-28 06:02:39 -07:00
Android.bp [libyuv] Add Qualcomm Hexagon HVX SIMD support 2026-10-19 14:16:18 -07:00
Android.mk [libyuv] Add Qualcomm Hexagon HVX SIMD support 2026-10-19 14:16:18 -07:00
AUTHORS Fix same-width vertical point upsampling 2026-08-24 19:28:50 -07:00
BUILD.bazel [libyuv] Add WASM SIMD128 and Relaxed SIMD for RAWToRGB24Row 2026-10-05 17:45:41 -07:00
BUILD.gn [libyuv] Add Qualcomm Hexagon HVX SIMD support 2026-10-19 14:16:18 -07:00
CM_linux_packages.cmake Use grep extended regex for version 2024-11-13 02:11:17 +00:00
CMakeLists.txt [libyuv] Add Qualcomm Hexagon HVX SIMD support 2026-10-19 14:16:18 -07:00
codereview.settings [infra] remove no longer supported git cl upload setting. 2021-04-28 12:47:52 +00:00
DEPS [build] Use hermetic python3 for script_executable in .gn 2026-09-28 06:02:39 -07:00
DIR_METADATA Move metadata in OWNERS files to DIR_METADATA files 2021-02-09 19:34:43 +00:00
download_vs_toolchain.py Update pylintrc to a pep-8 like style 2024-12-18 05:38:56 -08:00
GEMINI.md [libyuv] Fix MSan uninitialized errors in AVX512 alpha and scale rows 2026-10-27 16:27:29 -07:00
libyuv.bzl [libyuv] Simplify RVV configuration in BUILD.bazel and libyuv.bzl 2026-09-08 17:50:17 -07:00
libyuv.gni [libyuv] Fix RISC-V CMake/GN/Bazel builds and C compiler driver linking 2026-09-28 10:59:30 -07:00
libyuv.gyp Stop setting --dynamic-linker for target_os="android" 2026-05-27 04:34:07 -07:00
libyuv.gypi [libyuv] Add Qualcomm Hexagon HVX SIMD support 2026-10-19 14:16:18 -07:00
LICENSE Update Copyright notice to follow new chromium conventions. 2012-08-08 19:04:24 +00:00
linux.mk [libyuv] Optimize SsimWindowRow with SIMD and use compare_win on x86 2026-10-20 15:00:52 -07:00
OWNERS Remove magjed from OWNERS 2026-08-24 10:43:21 -07:00
PATENTS LibYuv: Adding PATENT and LICENSE files 2011-10-25 16:15:49 +00:00
PRESUBMIT.py Update pylintrc to a pep-8 like style 2024-12-18 05:38:56 -08:00
public.mk use unix line endings 2018-06-20 23:19:59 +00:00
pylintrc Update pylintrc to a pep-8 like style 2024-12-18 05:38:56 -08:00
README.chromium [libyuv] Add AVX-512 VNNI row functions for ARGB to YUV and Gray 2026-10-26 14:07:50 -07:00
README.md Update README.md and environment_variables.md for Arm 2024-09-20 00:29:33 +00:00
vpython.toml [vpython] Migrate .vpython3 to vpython.toml 2026-09-18 00:28:26 -07:00
vpython.toml.uv.lock [vpython] Migrate .vpython3 to vpython.toml 2026-09-18 00:28:26 -07:00
winarm.mk NV12 Copy, include scale_uv.h 2020-12-08 18:54:16 +00:00
WORKSPACE.bazel Add Bazel build support 2026-04-15 18:20:26 -07:00

libyuv is an open source project that includes YUV scaling and conversion functionality.

  • Scale YUV to prepare content for compression, with point, bilinear or box filter.
  • Convert to YUV from webcam formats for compression.
  • Convert to RGB formats for rendering/effects.
  • Rotate by 90/180/270 degrees to adjust for mobile devices in portrait mode.
  • Optimized for SSSE3/AVX2 on x86/x64.
  • Optimized for Neon/SVE2/SME on Arm.
  • Optimized for MSA on Mips.
  • Optimized for RVV on RISC-V.

Development

See Getting started for instructions on how to get started developing.

You can also browse the docs directory for more documentation.