AArch64: Revert previous branch optimization #4509
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Revert a branch optimization that was based on an incorrect assumption in the AArch64 part of ZSTD_decodeSequence. In extreme cases the existing implementation could lead to data corruption. Insert an UNLIKELY hint to guide the compilers toward generating more efficient machine code.
Remove the 32-bit code paths from the AArch64 only sections of ZSTD_decodeSequence.
Cyan4973
approved these changes
Oct 8, 2025
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This is a follow-up PR of #4418.
Revert a branch optimization that was based on an incorrect assumption in the AArch64 part of
ZSTD_decodeSequence. In extreme cases the existing implementation could lead to data corruption. Related discussion (measurements included): #4418 (comment)Insert an
UNLIKELYhint to guide the compilers toward generating more efficient machine code.Remove the 32-bit code paths from the AArch64 only sections of
ZSTD_decodeSequence.