[clang] [llvm] [AMDGPU] Add initial support for VGPR as memory (PR #205435)

[Diana Picus via cfe-commits]

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@@ -2275,6 +2288,10 @@ void AMDGPUCodeGenPassBuilder::addIRPasses(PassManagerWrapper &PMW) const {
   if (EnableLowerModuleLDS)
     addModulePass(AMDGPULowerModuleLDSPass(TM), PMW);
 
+  // Lay out "VGPR as memory" (addrspace(13)) globals into a shared register
+  // file (see the legacy pipeline above for details).
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rovka wrote:

I'd say this is the other way around - you should add the comments here and either duplicate or reference to this from the legacy infra (since in a distant future that might get removed and people might not notice and update this comment in the process).

https://github.com/llvm/llvm-project/pull/205435