[PATCH] D114652: [AMDGPU] Treat call clobbered return address registers s[30:31] as callee saved
Venkata Ramanaiah Nalamothu via Phabricator via llvm-commits
llvm-commits at lists.llvm.org
Fri Nov 26 10:37:54 PST 2021
RamNalamothu created this revision.
RamNalamothu added reviewers: rampitec, arsenm, scott.linder, t-tye, cdevadas, foad, tpr, tsymalla, sebastian-ne.
Herald added subscribers: kerbowa, hiraditya, dstuttard, yaxunl, nhaehnle, jvesely, kzhuravl, qcolombet.
RamNalamothu requested review of this revision.
Herald added subscribers: llvm-commits, wdng.
Herald added a project: LLVM.
Currently the return address ABI registers s[30:31], which fall in the call
clobbered register range, are added as a live-in on the function entry to
preserve its value when we have calls so that it gets saved and restored
around the calls.
But the DWARF unwind information (CFI) needs to track where the return address
resides in a frame and the above approach makes it difficult to track the
return address when the CFI information is emitted during the frame lowering
due to the involvment of understanding the control flow.
This patch delays handling the return address registers clobbering when we have
calls by treating the s[30:31] registers as callee saved and CFI machinery will
know where the return address resides when CSR save/restore happen during the
frame lowering.
To achieve that, the return address register use by the return instruction is
hidden through the `SI_RETURN` pseudo instruction, which doesn't take any input
operands, until the `SI_RETURN` pseudo gets lowered to the `S_SETPC_B64_return`
during the `expandPostRAPseudo()`.
Note: The AMDGPU CFI changes are there only in the downstream code and another
version of this patch will be posted for review for the downstream code.
Repository:
rG LLVM Github Monorepo
https://reviews.llvm.org/D114652
Files:
llvm/lib/Target/AMDGPU/AMDGPUCallLowering.cpp
llvm/lib/Target/AMDGPU/AMDGPUISelLowering.cpp
llvm/lib/Target/AMDGPU/AMDGPUISelLowering.h
llvm/lib/Target/AMDGPU/AMDGPUInstrInfo.td
llvm/lib/Target/AMDGPU/AMDGPUMCInstLower.cpp
llvm/lib/Target/AMDGPU/SIISelLowering.cpp
llvm/lib/Target/AMDGPU/SIInsertWaitcnts.cpp
llvm/lib/Target/AMDGPU/SIInstrInfo.cpp
llvm/lib/Target/AMDGPU/SIInstructions.td
llvm/lib/Target/AMDGPU/SILowerSGPRSpills.cpp
llvm/lib/Target/AMDGPU/SIRegisterInfo.cpp
llvm/lib/Target/AMDGPU/SIRegisterInfo.td
llvm/lib/Target/AMDGPU/SOPInstructions.td
llvm/test/CodeGen/AMDGPU/GlobalISel/combine-shift-imm-chain-illegal-types.mir
llvm/test/CodeGen/AMDGPU/GlobalISel/dummy-target.ll
llvm/test/CodeGen/AMDGPU/GlobalISel/fdiv.f32.ll
llvm/test/CodeGen/AMDGPU/GlobalISel/fdiv.f64.ll
llvm/test/CodeGen/AMDGPU/GlobalISel/fpow.ll
llvm/test/CodeGen/AMDGPU/GlobalISel/fshl.ll
llvm/test/CodeGen/AMDGPU/GlobalISel/fshr.ll
llvm/test/CodeGen/AMDGPU/GlobalISel/function-returns.ll
llvm/test/CodeGen/AMDGPU/GlobalISel/global-value.ll
llvm/test/CodeGen/AMDGPU/GlobalISel/irtranslator-atomicrmw.ll
llvm/test/CodeGen/AMDGPU/GlobalISel/irtranslator-call-abi-attribute-hints.ll
llvm/test/CodeGen/AMDGPU/GlobalISel/irtranslator-call-implicit-args.ll
llvm/test/CodeGen/AMDGPU/GlobalISel/irtranslator-call-non-fixed.ll
llvm/test/CodeGen/AMDGPU/GlobalISel/irtranslator-call-return-values.ll
llvm/test/CodeGen/AMDGPU/GlobalISel/irtranslator-call.ll
llvm/test/CodeGen/AMDGPU/GlobalISel/irtranslator-constantexpr.ll
llvm/test/CodeGen/AMDGPU/GlobalISel/irtranslator-constrained-fp.ll
llvm/test/CodeGen/AMDGPU/GlobalISel/irtranslator-fixed-function-abi-vgpr-args.ll
llvm/test/CodeGen/AMDGPU/GlobalISel/irtranslator-function-args.ll
llvm/test/CodeGen/AMDGPU/GlobalISel/irtranslator-getelementptr.ll
llvm/test/CodeGen/AMDGPU/GlobalISel/irtranslator-indirect-call.ll
llvm/test/CodeGen/AMDGPU/GlobalISel/irtranslator-inline-asm.ll
llvm/test/CodeGen/AMDGPU/GlobalISel/irtranslator-memory-intrinsics.ll
llvm/test/CodeGen/AMDGPU/GlobalISel/irtranslator-metadata.ll
llvm/test/CodeGen/AMDGPU/GlobalISel/irtranslator-ptrmask.ll
llvm/test/CodeGen/AMDGPU/GlobalISel/irtranslator-sat.ll
llvm/test/CodeGen/AMDGPU/GlobalISel/irtranslator-sibling-call.ll
llvm/test/CodeGen/AMDGPU/GlobalISel/irtranslator-tail-call.ll
llvm/test/CodeGen/AMDGPU/GlobalISel/llvm.amdgcn.ds.fmax.ll
llvm/test/CodeGen/AMDGPU/GlobalISel/load-unaligned.ll
llvm/test/CodeGen/AMDGPU/GlobalISel/regbankcombiner-smed3.mir
llvm/test/CodeGen/AMDGPU/GlobalISel/regbankcombiner-umed3.mir
llvm/test/CodeGen/AMDGPU/GlobalISel/roundeven.ll
llvm/test/CodeGen/AMDGPU/GlobalISel/saddsat.ll
llvm/test/CodeGen/AMDGPU/GlobalISel/ssubsat.ll
llvm/test/CodeGen/AMDGPU/GlobalISel/uaddsat.ll
llvm/test/CodeGen/AMDGPU/GlobalISel/usubsat.ll
llvm/test/CodeGen/AMDGPU/abi-attribute-hints-undefined-behavior.ll
llvm/test/CodeGen/AMDGPU/amdpal-callable.ll
llvm/test/CodeGen/AMDGPU/branch-relax-spill.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-sgprs-fixed-abi.ll
llvm/test/CodeGen/AMDGPU/callee-special-input-sgprs.ll
llvm/test/CodeGen/AMDGPU/cross-block-use-is-not-abi-copy.ll
llvm/test/CodeGen/AMDGPU/fdiv-nofpexcept.ll
llvm/test/CodeGen/AMDGPU/fix-frame-ptr-reg-copy-livein.ll
llvm/test/CodeGen/AMDGPU/fpow.ll
llvm/test/CodeGen/AMDGPU/frame-setup-without-sgpr-to-vgpr-spills.ll
llvm/test/CodeGen/AMDGPU/fshr.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/inline-asm.i128.ll
llvm/test/CodeGen/AMDGPU/ipra.ll
llvm/test/CodeGen/AMDGPU/llvm.amdgcn.implicitarg.ptr.ll
llvm/test/CodeGen/AMDGPU/llvm.powi.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-remat-indirect-mov.mir
llvm/test/CodeGen/AMDGPU/no-source-locations-in-prologue.ll
llvm/test/CodeGen/AMDGPU/reserve-vgpr-for-sgpr-spill.ll
llvm/test/CodeGen/AMDGPU/save-fp.ll
llvm/test/CodeGen/AMDGPU/sibling-call.ll
llvm/test/CodeGen/AMDGPU/stack-realign.ll
llvm/test/CodeGen/AMDGPU/strict_fadd.f16.ll
llvm/test/CodeGen/AMDGPU/strict_fmul.f16.ll
llvm/test/CodeGen/AMDGPU/strict_fsub.f16.ll
llvm/test/CodeGen/AMDGPU/tail-call-amdgpu-gfx.ll
llvm/test/CodeGen/AMDGPU/udiv.ll
llvm/test/CodeGen/AMDGPU/udiv64.ll
llvm/test/CodeGen/AMDGPU/unstructured-cfg-def-use-issue.ll
llvm/test/CodeGen/AMDGPU/urem-seteq-illegal-types.ll
llvm/test/CodeGen/AMDGPU/urem64.ll
llvm/test/CodeGen/AMDGPU/vgpr-tuple-allocation.ll
llvm/test/CodeGen/AMDGPU/wave32.ll
llvm/test/CodeGen/AMDGPU/wwm-reserved-spill.ll
llvm/test/CodeGen/MIR/AMDGPU/machine-metadata.mir
llvm/test/CodeGen/MIR/AMDGPU/stack-id-assert.mir
More information about the llvm-commits
mailing list