[clang] [CIR] Upstream support for function/call calling conventions (PR #181170)

[Sirui Mu via cfe-commits]

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@@ -882,16 +883,30 @@ static mlir::ParseResult parseCallCommon(mlir::OpAsmParser &parser,
   if (parser.resolveOperands(ops, opsFnTy.getInputs(), opsLoc, result.operands))
     return mlir::failure();
 
+  bool hasCallConv = parser.parseOptionalKeyword("cc").succeeded() ||
+                     parser.parseOptionalKeyword("call_conv").succeeded();
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Lancern wrote:

Is `call_conv` actually used?

https://github.com/llvm/llvm-project/pull/181170