[clang] [libc] [llvm] [AMDGPU] Implement variadic functions by IR lowering (PR #93362)

[Jon Chesterfield via cfe-commits]

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@@ -992,6 +993,8 @@ void AMDGPUPassConfig::addIRPasses() {
   if (isPassEnabled(EnableImageIntrinsicOptimizer))
     addPass(createAMDGPUImageIntrinsicOptimizerPass(&TM));
 
+  addPass(createExpandVariadicsPass(ExpandVariadicsMode::Lowering));
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JonChesterfield wrote:

I'm also paranoid enough to want that, it's '--expand-variadics-override=disable' from the command line or changing the ::Lowering in that line to ::Disable. Commenting out the addPass also kills it, but would cause the lit pipeline tests to fail. I'll put a comment above that pass saying this.

https://github.com/llvm/llvm-project/pull/93362