[llvm] [InlineAsm] wrap ConstraintCode in enum class NFC (PR #66003)

[Nick Desaulniers via llvm-commits]

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@@ -2521,13 +2521,13 @@ AVRTargetLowering::getConstraintType(StringRef Constraint) const {
   return TargetLowering::getConstraintType(Constraint);
 }
 
-unsigned
+InlineAsm::ConstraintCode
 AVRTargetLowering::getInlineAsmMemConstraint(StringRef ConstraintCode) const {
   // Not sure if this is actually the right thing to do, but we got to do
   // *something* [agnat]
   switch (ConstraintCode[0]) {
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nickdesaulniers wrote:

Sorry @bwendling , I agree with @jrtc27 .  These kinds of memory-only constraints don't get added often, but I also doubt that LLVM supports all of https://gcc.gnu.org/onlinedocs/gcc/Machine-Constraints.html for all backend LLVM has.  I forsee these changing, at least for the more modern and well supported architectures.

https://github.com/llvm/llvm-project/pull/66003