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

[Matt Arsenault via llvm-commits]

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@@ -90,6 +90,14 @@ bool SystemZTargetInfo::validateAsmConstraint(
   case 'T': // Likewise, plus an index
     Info.setAllowsMemory();
     return true;
+  case '@':
+    // CC condition changes.
+    if (strlen(Name) >= 3 && *(Name + 1) == 'c' && *(Name + 2) == 'c') {
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arsenm wrote:

Avoid strlen, use StringRef 

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