[PATCH] D134788: [ARM64EC][clang-cl] Add /arm64EC flag

[chenglin.bi via Phabricator via cfe-commits]

bcl5980 added inline comments.


================
Comment at: clang/lib/Driver/Driver.cpp:1384
+      TC.getTriple().getSubArch() != llvm::Triple::AArch64SubArch_arm64ec) {
+    if (UArgs->hasArg(options::OPT__SLASH_arm64EC)) {
+      getDiags().Report(clang::diag::warn_target_override_arm64ec)
----------------
DavidSpickett wrote:
> DavidSpickett wrote:
> > This would read better to me if you put them all in one and put the most important check first like:
> > ```
> > if ( UArgs->hasArg(options::OPT__SLASH_arm64EC) &&
> >     ( (TC.getTriple().getArch() != llvm::Triple::aarch64 ||
> >       TC.getTriple().getSubArch() != llvm::Triple::AArch64SubArch_arm64ec)) {
> > ```
> This is good but I didn't emphasise one bit. Putting the arm64ec option check first saves reading the rest if the reader knows it's not relevant.
I believe the condition `UArgs->hasArg(options::OPT__SLASH_arm64EC)` should be much heavier than 
`(TC.getTriple().getArch() != llvm::Triple::aarch64 || TC.getTriple().getSubArch() != llvm::Triple::AArch64SubArch_arm64ec)`.
So I put the Arch and SubArch check first here. I don't understand why we should put the hasArg check first.


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D134788/new/

https://reviews.llvm.org/D134788