[clang] [CIR] Upstream support for type aliases (PR #131912)

[Andy Kaylor via cfe-commits]

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@@ -31,6 +31,20 @@ struct CIROpAsmDialectInterface : public OpAsmDialectInterface {
   using OpAsmDialectInterface::OpAsmDialectInterface;
 
   AliasResult getAlias(Type type, raw_ostream &os) const final {
+    if (auto intType = dyn_cast<cir::IntType>(type)) {
+      // We only provide alias for standard integer types (i.e. integer types
+      // whose width is a power of 2 and at least 8).
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andykaylor wrote:

The incubator is only checking `width % 8 == 0`, but that creates aliases for things like `!cir.int<s, 48>`, which I don't think is what was intended.

https://github.com/llvm/llvm-project/pull/131912