[llvm] [AMDGPU][GlobalISel] Enable kernel argument preloading (PR #134655)

[Austin Kerbow via llvm-commits]

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@@ -520,7 +522,6 @@ bool AMDGPUCallLowering::lowerFormalArgumentsKernel(
 
   // TODO: Align down to dword alignment and extract bits for extending loads.
   for (auto &Arg : F.args()) {
-    // TODO: Add support for kernarg preload.
     if (Arg.hasAttribute("amdgpu-hidden-argument")) {
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kerbowa wrote:

I guess support for hidden args can be added separately?

https://github.com/llvm/llvm-project/pull/134655