[clang] Make CIR assembly formats strict properties compatible (PR #226600)

[Henrich Lauko via cfe-commits]

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@@ -327,7 +325,8 @@ def CIR_CastOp : CIR_Op<"cast", !listconcat([
   let results = (outs CIR_AnyType:$result);
 
   let assemblyFormat = [{
-    enum($kind) $src `:` type($src) `->` type($result) attr-dict
+    enum($kind) $src `:` type($src) `->` type($result)
+    (`fenv` `` custom<FenvFields>($fenv)^)? attr-dict
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xlauko wrote:

uff sorry, I did not mean custom format. We try to to minimize its use only to necessary uses, it tends to creep in random parse/print misalignment errors, and is poorly extendable. If there is no way to do my suggested change in pure assemblyFormat lets keep the repeated form for now.

https://github.com/llvm/llvm-project/pull/226600