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Re: [PATCH i386 3/8] [AVX512] [11/n] Add AVX-512 patterns: FMA.


On 10/09/2013 03:28 AM, Kirill Yukhin wrote:
> +;; CPUID bit AVX512F enables evex encoded scalar and 512-bit fma.  It doesn't
> +;; care about FMA bit, so we enable fma for TARGET_AVX512F even when TARGET_FMA
> +;; and TARGET_FMA4 are both false.

How do you force an evex encoding of the instruction?

Do you really mean that cpuid AVX512F, !FMA will not #OP
for a vex (but not evex) encoded version of the same insn?


r~


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