[PATCH] D99269: [AMDGPU] Unify spill code

[Sebastian Neubauer via Phabricator via llvm-commits]

sebastian-ne added inline comments.


================
Comment at: llvm/lib/Target/AMDGPU/SIRegisterInfo.cpp:1456-1459
+      // Use the stack pointer instead of the frame pointer for restores in the
+      // function epilog.
+      if (Flags & 1)
+        FrameReg = MFI->getStackPtrOffsetReg();
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arsenm wrote:
> I don't like having this logic separated and overriding the frame register logic above. Can you infer this should be SP relative from the frame index itself instead of adding a new operand?
How should that work? Should I add a new `TargetStackID::PrologEpilogSave`?

It is not really a property of the frame index that SP should be used, it is because the instruction is in the prolog/epilog where FP is not setup. If we wanted to access the same frame index in the function body, we would need to use FP instead of SP.

I could move this code out of the switch and merge it with the frame register logic above, but that doesn’t change much.


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  https://reviews.llvm.org/D99269/new/

https://reviews.llvm.org/D99269