Fix BLAKE3 NEON rot8 build on armv7 - #28
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rot8_neon used vqtbl1q_u8, which is only available on AArch64. That broke armv7 NEON builds at the call site. Use the BLAKE3 reference approach instead: Clang shufflevector, GCC 4.7+ shuffle, and a vsriq_n_u32 fallback. Refs: #27
Coralesoft
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May 14, 2026 11:32
This was referenced May 14, 2026
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Summary
Fixes the armv7 NEON build of
blake3_simd.cpp.rot8_neonusedvqtbl1q_u8, which is AArch64-only. armv7 NEON only supports VTBL with 8-byte inputs.Replace it with the BLAKE3 reference approach: Clang
__builtin_shufflevector, GCC 4.7+__builtin_shuffle, and avsriq_n_u32fallback.On AArch64, Clang and GCC still lower this to
TBL, with bit-identical output to the previous path.The remaining
cpu-features.hitem in #27 is a separate upstream-inherited CMake gap and will be handled separately.Verification
armv7-linux-gnueabihfandaarch64-linux-gnuwith LLVM 22.cryptest.exe vpassed.cryptest.exe v 88BLAKE3 KATs passed: 5/5.Refs: #27