Alan Kelly f4b044bbe3 swscale: Disable avx2 hscale 8to15 on IceLake and below due to Intel Gather Data Sampling mitigation performance loss ...

Intel provided a microcode update to mitigate this security
    vulnerability which has a huge negative performance impact on gather
    instructions. This means that hscale 8to15 avx2, which uses gather
    extensively, is no longer faster than SSSE3 on impacted CPUs.

    https://www.intel.com/content/www/us/en/developer/articles/technical/software-security-guidance/technical-documentation/gather-data-sampling.html

    Broadwell:
    hscale_8_to_15__fs_4_dstW_512_c:                      3379.5 ( 1.00x)
    hscale_8_to_15__fs_4_dstW_512_sse2:                    615.7 ( 5.49x)
    hscale_8_to_15__fs_4_dstW_512_ssse3:                   613.4 ( 5.51x)
    hscale_8_to_15__fs_4_dstW_512_avx2:                    495.7 ( 6.82x)

    Skylake:
    hscale_8_to_15__fs_4_dstW_512_c:                      3411.4 ( 1.00x)
    hscale_8_to_15__fs_4_dstW_512_sse2:                    591.0 ( 5.77x)
    hscale_8_to_15__fs_4_dstW_512_ssse3:                   591.5 ( 5.77x)
    hscale_8_to_15__fs_4_dstW_512_avx2:                   1386.2 ( 2.46x)

    Cascade Lake:
    hscale_8_to_15__fs_4_dstW_512_c:                      3231.3 ( 1.00x)
    hscale_8_to_15__fs_4_dstW_512_sse2:                    517.9 ( 6.24x)
    hscale_8_to_15__fs_4_dstW_512_ssse3:                   521.6 ( 6.19x)
    hscale_8_to_15__fs_4_dstW_512_avx2:                   1775.0 ( 1.82x)

    Sapphire Rapids:
    hscale_8_to_15__fs_4_dstW_512_c:                      1840.0 ( 1.00x)
    hscale_8_to_15__fs_4_dstW_512_sse2:                    287.9 ( 6.39x)
    hscale_8_to_15__fs_4_dstW_512_ssse3:                   293.8 ( 6.26x)
    hscale_8_to_15__fs_4_dstW_512_avx2:                    219.2 ( 8.40x)

2025-09-06 20:57:48 +00:00

..

aes_init.c

avutil/x86/aes: remove a few branches

2025-04-10 12:02:34 -03:00

aes.asm

avutil/x86/aes: remove a few branches

2025-04-10 12:02:34 -03:00

asm.h

…

bswap.h

…

cpu.c

swscale: Disable avx2 hscale 8to15 on IceLake and below due to Intel Gather Data Sampling mitigation performance loss

2025-09-06 20:57:48 +00:00

cpu.h

…

cpuid.asm

…

emms.asm

…

fixed_dsp_init.c

…

fixed_dsp.asm

…

float_dsp_init.c

…

float_dsp.asm

…

imgutils_init.c

…

imgutils.asm

…

intmath.h

avutil/intmath: use AV_HAS_BUILTIN to detect builtin availability

2025-06-12 14:17:37 +03:00

intreadwrite.h

…

lls_init.c

…

lls.asm

…

Makefile

…

pixelutils_init.c

…

pixelutils.asm

…

pixelutils.h

…

timer.h

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tx_float_init.c

…

tx_float.asm

…

w64xmmtest.h

…

x86inc.asm

…

x86util.asm

…