[PATCH] D152892: [AMDGPU] Remove return VGPRs from callee save list

[Jannik Silvanus via Phabricator via llvm-commits]

jsilvanus added inline comments.


================
Comment at: llvm/lib/Target/AMDGPU/SIFrameLowering.cpp:1527
+
+  // Remove any VGPRs used in the return value these do not need to be saved.
+  // This prevents CSR restore from clobbering return VGPRs.
----------------
"[...] because these do not [...]"?


================
Comment at: llvm/lib/Target/AMDGPU/SIFrameLowering.cpp:1529
+  // This prevents CSR restore from clobbering return VGPRs.
+  // Note: this assumes all return instructions are of equal.
+  if (ReturnMI) {
----------------
"[...] of equal type / size"?

Maybe add an assertion above when finding multiple returns?


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D152892/new/

https://reviews.llvm.org/D152892