[PATCH] D157680: [X86]Support options -mno-gather -mno-scatter

[Fangrui Song via Phabricator via cfe-commits]

MaskRay added inline comments.


================
Comment at: clang/include/clang/Driver/Options.td:903-906
+def mno_gather : Flag<["-"], "mno-gather">, Flags<[NoXarchOption]>,
+                 HelpText<"Disable generation of gather instructions in auto-vectorization(x86 only)">;
+def mno_scatter : Flag<["-"], "mno-scatter">, Flags<[NoXarchOption]>,
+                  HelpText<"Disable generation of scatter instructions in auto-vectorization(x86 only)">;
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pengfei wrote:
> Move under "// X86 feature flags"
Also remove `NoXarchOption`

https://maskray.me/blog/2021-03-28-compiler-driver-and-cross-compilation#misc

If an option has the NoXarchOption flag, ClangDriver will emit an error if the option is used after -Xarch_* (originally for universal macOS binary, reused by offloading purposes -Xarch_host/etc). The error checking only applies to a small set of options (e.g. -o) and is not very useful for most options, but NoXarchOption was improperly named DriverOption (commit aabb0b11a3c1d8a6bb859db80400cffdcc9b336f) and lured some contributors to add NoXarchOption to options that should not have the flag.


Repository:
  rG LLVM Github Monorepo

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  https://reviews.llvm.org/D157680/new/

https://reviews.llvm.org/D157680