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

[Andy Kaylor via cfe-commits]

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@@ -464,15 +464,35 @@ OpFoldResult cir::CastOp::fold(FoldAdaptor adaptor) {
 // CallOp
 //===----------------------------------------------------------------------===//
 
+mlir::OperandRange cir::CallOp::getArgOperands() {
+  if (isIndirect())
+    return getArgs().drop_front(1);
+  return getArgs();
+}
+
+mlir::MutableOperandRange cir::CallOp::getArgOperandsMutable() {
+  mlir::MutableOperandRange args = getArgsMutable();
+  if (isIndirect())
+    return args.slice(1, args.size() - 1);
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andykaylor wrote:

I guess `mlir::MutableOperandRange` doesn't support `drop_front()`?

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