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Re: [PATCH x86_64][BZ #20139] Don't allow configure with not supporting AVX512 assembler w/o --disable-avx512.

On 06/29/2016 11:45 PM, H.J. Lu wrote:

Subject: [PATCH] Require binutils 2.24 to build x86-64 glibc


Please put [BZ #20139] at the end of the first line.


If assembler doesn't support , _dl_runtime_resolve_avx is used
to save the first 8 vector registers, which only saves the lower 256
bits of vector register, for lazy binding.  When it is called on AVX512
platform, the upper 256 bits of ZMM registers are clobbered.  Parameters
passed in ZMM registers will be wrong when the function is called the
first time.  This patch requires binutils 2.24, whose assembler can store
and load ZMM registers, to build x86-64 glibc.  Since mathvec library
needs assembler support for AVX512DQ,  we disable mathvec if assembler
doesn't support AVX512DQ.
The commit message seems to be inconsistent. Should the “AVX512DQ” on the first line actually be “AVX512F”? 

Thanks,
Florian
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