[clang] [CIR] Cleanup support for C functions (PR #136854)

[Andy Kaylor via cfe-commits]

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@@ -32,8 +32,14 @@ void X8664ABIInfo::computeInfo(CIRGenFunctionInfo &funcInfo) const {
   // Top level CIR has unlimited arguments and return types. Lowering for ABI
   // specific concerns should happen during a lowering phase. Assume everything
   // is direct for now.
-  assert(!cir::MissingFeatures::opCallArgs());
-
+  for (CIRGenFunctionInfo::arg_iterator it = funcInfo.arg_begin(),
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andykaylor wrote:

Can you use a range-based for loop here?

https://github.com/llvm/llvm-project/pull/136854