Commits on Source (2)
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Martin Storsjö authored
We don't expect the user to build the whole x264 codebase with SVE/SVE2 enabled, as we only enable this feature for the assembly files that use it, in order to have binaries that are portable and enable the SVE codepaths at runtime if supported.
db9bc75b -
Martin Storsjö authored
We could also use HWCAP_SVE and HWCAP2_SVE2 for detecting this, but these might not be available in all userland headers, while HWCAP_CPUID is available much earlier. The register ID_AA64ZFR0_EL1, which indicates if SVE2 is available, can only be accessed if SVE is available. If not building all the C code with SVE enabled (which could make it impossible to run on on HW without SVE), binutils refuses to assemble an instruction reading ID_AA64ZFR0_EL1 - but if referring to it with the technical name S3_0_C0_C4_4, it can be assembled even without any extra extensions enabled.
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