[clang] [CIR] Add support for indirect calls (PR #139748)

[Sirui Mu via cfe-commits]

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@@ -1861,13 +1867,23 @@ def CallOp : CIR_CallOpBase<"call", [NoRegionArguments]> {
   let arguments = commonArgs;
 
   let builders = [OpBuilder<(ins "mlir::SymbolRefAttr":$callee,
-                                 "mlir::Type":$resType,
-                                 "mlir::ValueRange":$operands), [{
+                                "mlir::Type":$resType,
+                                "mlir::ValueRange":$operands),
+                            [{
       $_state.addOperands(operands);
       $_state.addAttribute("callee", callee);
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Lancern wrote:

Since this builder is for building a direct call I believe it's more proper to have an assertion here that ensure `callee` is non-empty.

https://github.com/llvm/llvm-project/pull/139748