[llvm] [NFC][LLVM] Refactor rounding mode detection of constrained fp intrinsic IDs (PR #90854)

[Joshua Cranmer via llvm-commits]

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@@ -1491,7 +1491,19 @@ bool Intrinsic::isConstrainedFPIntrinsic(ID QID) {
 #define INSTRUCTION(NAME, NARG, ROUND_MODE, INTRINSIC)                         \
   case Intrinsic::INTRINSIC:
 #include "llvm/IR/ConstrainedOps.def"
+#undef INSTRUCTION
     return true;
+  default:
+    return false;
+  }
+}
+
+bool Intrinsic::hasConstrainedFPRoundingModeOperand(Intrinsic::ID QID) {
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jcranmer-intel wrote:

> I think these would be better as some kind of optional tag on call or an operand bundle or something

Playing around with an implementation of this has long been on a TODO list of mine, but I've not yet had time to try it out.

https://github.com/llvm/llvm-project/pull/90854