[PATCH] D115551: [AMDGPU] Do not reserve any VGPR for SGPR spills

Thu Dec 30 00:21:28 PST 2021

kerbowa added a reviewer: ruiling.
kerbowa added inline comments.

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Comment at: llvm/lib/Target/AMDGPU/SIFrameLowering.cpp:1321-1323
-  const bool WillHaveFP =
-      FrameInfo.hasCalls() && (HaveAnyCSRVGPR || MFI->VGPRReservedForSGPRSpill);

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arsenm wrote:
> kerbowa wrote:
> > arsenm wrote:
> > > I don't see why you're changing this, this is still an issue?
> > With the change, we are being more conservative.
> But why, I don't see the connection to eliminating the reserved register
We would usually reserve a register so this check was essentially always true if the function had calls. I've updated the condition since we will have a FP if there are any CSR SGPR spills too.

Repository:
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CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D115551/new/

https://reviews.llvm.org/D115551