fix uninitialized mul_one in AVX2 checksum and add SIMD checksum test#859
Merged
tridge merged 2 commits intoRsyncProject:masterfrom Mar 1, 2026
Merged
fix uninitialized mul_one in AVX2 checksum and add SIMD checksum test#859tridge merged 2 commits intoRsyncProject:masterfrom
tridge merged 2 commits intoRsyncProject:masterfrom
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The AVX2 get_checksum1_avx2_64() read mul_one before initializing it, which is undefined behavior. Replace the cmpeq/abs trick with _mm256_set1_epi8(1) to match the SSSE3 and SSE2 versions. Add a TEST_SIMD_CHECKSUM1 test mode that verifies all SIMD paths (SSE2, SSSE3, AVX2, and the full dispatch chain) produce identical results to the C reference, across multiple buffer sizes with both aligned and unaligned buffers. Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
The new simd-checksum test is skipped on platforms where SIMD instructions are unavailable (macOS ARM, Cygwin). Add it to the RSYNC_EXPECT_SKIPPED lists so CI doesn't fail on the mismatch. Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
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The AVX2 get_checksum1_avx2_64() read mul_one before initializing it, which is undefined behavior. Replace the cmpeq/abs trick with _mm256_set1_epi8(1) to match the SSSE3 and SSE2 versions.
Add a TEST_SIMD_CHECKSUM1 test mode that verifies all SIMD paths (SSE2, SSSE3, AVX2, and the full dispatch chain) produce identical results to the C reference, across multiple buffer sizes with both aligned and unaligned buffers.
thanks to Joshua Rogers for reporting