[clang] [CIR] Freeze maybe_undef call arguments (PR #234124)

[Arseniy Obolenskiy via cfe-commits]

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@@ -1359,6 +1380,10 @@ RValue CIRGenFunction::emitCall(const CIRGenFunctionInfo &funcInfo,
       assert(!cir::MissingFeatures::lowerAggregateLoadStore());
       cirCallArgs[argNo] = builder.createLoad(argLoc, src);
     }
+
+    if (isArgumentMaybeUndef(targetDecl, funcInfo.getNumRequiredArgs(), argNo))
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aobolensk wrote:

CallConvLowering now moves the freeze onto the post-ABI values, like classic codegen, so coerced padding gets frozen too

https://github.com/llvm/llvm-project/pull/234124