llvm-project/llvm/test/CodeGen/AMDGPU/postra-norename.mir

14 lines
441 B
Plaintext
Raw Normal View History

[MachineOperand][Target] MachineOperand::isRenamable semantics changes Summary: Add a target option AllowRegisterRenaming that is used to opt in to post-register-allocation renaming of registers. This is set to 0 by default, which causes the hasExtraSrcRegAllocReq/hasExtraDstRegAllocReq fields of all opcodes to be set to 1, causing MachineOperand::isRenamable to always return false. Set the AllowRegisterRenaming flag to 1 for all in-tree targets that have lit tests that were effected by enabling COPY forwarding in MachineCopyPropagation (AArch64, AMDGPU, ARM, Hexagon, Mips, PowerPC, RISCV, Sparc, SystemZ and X86). Add some more comments describing the semantics of the MachineOperand::isRenamable function and how it is set and maintained. Change isRenamable to check the operand's opcode hasExtraSrcRegAllocReq/hasExtraDstRegAllocReq bit directly instead of relying on it being consistently reflected in the IsRenamable bit setting. Clear the IsRenamable bit when changing an operand's register value. Remove target code that was clearing the IsRenamable bit when changing registers/opcodes now that this is done conservatively by default. Change setting of hasExtraSrcRegAllocReq in AMDGPU target to be done in one place covering all opcodes that have constant pipe read limit restrictions. Reviewers: qcolombet, MatzeB Subscribers: aemerson, arsenm, jyknight, mcrosier, sdardis, nhaehnle, javed.absar, tpr, arichardson, kristof.beyls, kbarton, fedor.sergeev, asb, rbar, johnrusso, simoncook, jordy.potman.lists, apazos, sabuasal, niosHD, escha, nemanjai, llvm-commits Differential Revision: https://reviews.llvm.org/D43042 llvm-svn: 325931
2018-02-24 02:25:08 +08:00
# RUN: llc -march=amdgcn -mcpu=gfx900 -run-pass postrapseudos %s -o - | FileCheck -check-prefix=GCN %s
# Check that post-RA expanded COPY doesn't have renamable operands
# since V_MOV_B32_e32 has hasExtraSrcRegAllocReq set.
# GCN-LABEL: name: test1
# GCN: $vgpr1 = V_MOV_B32_e32 $vgpr0, implicit $exec
name: test1
tracksRegLiveness: true
body: |
bb.0:
liveins: $vgpr0
renamable $vgpr1 = COPY renamable $vgpr0
...