[clang] [llvm] Add support for flag output operand "=@cc" for SystemZ. (PR #125970)

[Ulrich Weigand via llvm-commits]

================
@@ -119,6 +119,12 @@ class LLVM_LIBRARY_VISIBILITY SystemZTargetInfo : public TargetInfo {
                              TargetInfo::ConstraintInfo &info) const override;
 
   std::string convertConstraint(const char *&Constraint) const override {
+    if (llvm::StringRef(Constraint) == "@cc") {
----------------
uweigand wrote:

This should read the same as the check in SystemZ.cpp above.  Why do we have `llvm::StringRef(Constraint) == "@cc"` here and `!StringRef("@cc").compare(Name)` above?  Decide which form is preferable and use that consistently.

https://github.com/llvm/llvm-project/pull/125970