[all-commits] [llvm/llvm-project] a70c3f: [compiler-rt] Don't check XCR0 when detecting avx5...

[Florian Hahn via All-commits]

  Branch: refs/heads/master
  Home:   https://github.com/llvm/llvm-project
  Commit: a70c3f9f45c8db3092db44110a992e9fd8ee776e
      https://github.com/llvm/llvm-project/commit/a70c3f9f45c8db3092db44110a992e9fd8ee776e
  Author: Florian Hahn <flo at fhahn.com>
  Date:   2019-11-21 (Thu, 21 Nov 2019)

  Changed paths:
    M compiler-rt/lib/builtins/cpu_model.c

  Log Message:
  -----------
  [compiler-rt] Don't check XCR0 when detecting avx512 on Darwin.

Darwin lazily saves the AVX512 context on first use [1]: instead of checking
that it already does to figure out if the OS supports AVX512, trust that
the kernel will do the right thing and always assume the context save
support is available.

[1] https://github.com/apple/darwin-xnu/blob/xnu-4903.221.2/osfmk/i386/fpu.c#L174

Reviewers: ab, RKSimon, craig.topper

Reviewed By: craig.topper

Subscribers: dberris, JDevlieghere, #sanitizers, llvm-commits

Tags: #sanitizers, #llvm

Differential Revision: https://reviews.llvm.org/D70454