darwin/arm64: fix SIMD detection and improve ARM feature probing#160
Merged
klauspost merged 3 commits intoklauspost:masterfrom May 14, 2025
Merged
darwin/arm64: fix SIMD detection and improve ARM feature probing#160klauspost merged 3 commits intoklauspost:masterfrom
klauspost merged 3 commits intoklauspost:masterfrom
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HippoBaro
commented
May 12, 2025
Detection of Advanced SIMD (NEON) on M1 Macs was broken due to querying the wrong sysctl identifier. Apple's documentation lists "hw.optional.AdvSIMD" as the correct identifier, but in reality, it's "hw.optional.arm.AdvSIMD" as confirmed by `sysctl -a`. This patch corrects the identifier and adds support for its alias, "hw.optional .neon," ensuring proper detection across all models. Additionally, this patch revisits all ARM features detected by the package, cross-referencing identifiers (and aliases) against both Apple's official sysctl documentation: https://developer.apple.com/documentation/kernel/1387446-sysctlbyname/determining_instruction_set_characteristics and the ARM architecture reference manual: https://developer.arm.com/documentation/ddi0487/latest Each ARM feature now maps to all known sysctl aliases, preventing false negatives and improving detection accuracy on Apple Silicon.
klauspost
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May 13, 2025
klauspost
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May 14, 2025
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LGTM. Thanks for the contribution! <3
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