[PATCH] D134949: [AMDGPU] Use the right frame register in custom CSR spills

[Christudasan Devadasan via Phabricator via llvm-commits]

cdevadas created this revision.
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Herald added subscribers: kosarev, foad, kerbowa, hiraditya, t-tye, tpr, dstuttard, yaxunl, nhaehnle, jvesely, kzhuravl, qcolombet, MatzeB.
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Unlike the callee-saved VGPR spill instructions emitted by
`PEI::spillCalleeSavedRegs`, the custom CS VGPR spills
inserted during emitPrologue/emitEpilogue require the exec bits
flipping to avoid clobbering the inactive lanes of VGPRs
used for SGPR spilling. Currently these spill instructions are
referenced from the SP at function entry and when the callee
performs a stack realignment, they ended up getting incorrect
stack offsets. Even if we try to adjust the offsets, the FP-SP
becomes a runtime entity with dynamic stack realignment and the
offsets would still be inaccurate.

To fix it, use FP as the frame base in the spill instructions
whenever the function has FP. The offsets obtained for the CS
objects would always be the right values from FP.


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D134949

Files:
  llvm/lib/Target/AMDGPU/SIFrameLowering.cpp
  llvm/lib/Target/AMDGPU/SIFrameLowering.h
  llvm/lib/Target/AMDGPU/SIMachineFunctionInfo.h
  llvm/test/CodeGen/AMDGPU/GlobalISel/assert-align.ll
  llvm/test/CodeGen/AMDGPU/GlobalISel/call-outgoing-stack-args.ll
  llvm/test/CodeGen/AMDGPU/GlobalISel/localizer.ll
  llvm/test/CodeGen/AMDGPU/abi-attribute-hints-undefined-behavior.ll
  llvm/test/CodeGen/AMDGPU/amdpal-callable.ll
  llvm/test/CodeGen/AMDGPU/call-graph-register-usage.ll
  llvm/test/CodeGen/AMDGPU/call-preserved-registers.ll
  llvm/test/CodeGen/AMDGPU/callee-frame-setup.ll
  llvm/test/CodeGen/AMDGPU/callee-special-input-vgprs-packed.ll
  llvm/test/CodeGen/AMDGPU/callee-special-input-vgprs.ll
  llvm/test/CodeGen/AMDGPU/cross-block-use-is-not-abi-copy.ll
  llvm/test/CodeGen/AMDGPU/dwarf-multi-register-use-crash.ll
  llvm/test/CodeGen/AMDGPU/fix-frame-reg-in-custom-csr-spills.ll
  llvm/test/CodeGen/AMDGPU/frame-setup-without-sgpr-to-vgpr-spills.ll
  llvm/test/CodeGen/AMDGPU/gfx-call-non-gfx-func.ll
  llvm/test/CodeGen/AMDGPU/gfx-callable-argument-types.ll
  llvm/test/CodeGen/AMDGPU/gfx-callable-preserved-registers.ll
  llvm/test/CodeGen/AMDGPU/gfx-callable-return-types.ll
  llvm/test/CodeGen/AMDGPU/indirect-call.ll
  llvm/test/CodeGen/AMDGPU/mul24-pass-ordering.ll
  llvm/test/CodeGen/AMDGPU/need-fp-from-vgpr-spills.ll
  llvm/test/CodeGen/AMDGPU/nested-calls.ll
  llvm/test/CodeGen/AMDGPU/no-source-locations-in-prologue.ll
  llvm/test/CodeGen/AMDGPU/pei-scavenge-sgpr-carry-out.mir
  llvm/test/CodeGen/AMDGPU/pei-scavenge-sgpr-gfx9.mir
  llvm/test/CodeGen/AMDGPU/pei-scavenge-sgpr.mir
  llvm/test/CodeGen/AMDGPU/pei-scavenge-vgpr-spill.mir
  llvm/test/CodeGen/AMDGPU/sgpr-spills-split-regalloc.ll
  llvm/test/CodeGen/AMDGPU/sibling-call.ll
  llvm/test/CodeGen/AMDGPU/spill-csr-frame-ptr-reg-copy.ll
  llvm/test/CodeGen/AMDGPU/stack-realign.ll
  llvm/test/CodeGen/AMDGPU/tail-call-amdgpu-gfx.ll
  llvm/test/CodeGen/AMDGPU/tuple-allocation-failure.ll
  llvm/test/CodeGen/AMDGPU/unstructured-cfg-def-use-issue.ll
  llvm/test/CodeGen/AMDGPU/vgpr-tuple-allocation.ll
  llvm/test/CodeGen/AMDGPU/wave32.ll
  llvm/test/CodeGen/AMDGPU/wwm-reserved-spill.ll