[PATCH] D73659: [GlobalISel] Add new combine to convert G_MUL to G_SHL.

Wed Jan 29 12:54:03 PST 2020

aemerson added a comment.

@arsenm Matt when I run the update_llc_test_checks script on the llvm/test/CodeGen/AMDGPU/GlobalISel/llvm.amdgcn.update.dpp.ll test, it crashes with a backtrace like this:

  Assertion failed: (Opcode < NumOpcodes && "Invalid opcode!"), function get, file /Users/aemerson/work/oss/co1/src/llvm/include/llvm/MC/MCInstrInfo.h, line 4
  frame #4: 0x00000001000bdef3 llc`llvm::MCInstrInfo::get(this=0x0000000110010248, Opcode=4294967295) const at MCInstrInfo.h:45:5
  frame #5: 0x000000010083b8d7 llc`llvm::SIInstrInfo::getMCOpcodeFromPseudo(this=0x0000000110010240, Opcode=3758) const at SIInstrInfo.h:939:12
  frame #6: 0x00000001008277e3 llc`llvm::SIInstrInfo::getInstSizeInBytes(this=0x0000000110010240, MI=0x000000010f879b28) const at SIInstrInfo.cpp:6067:29
  frame #7: 0x0000000101f9bf44 llc`(anonymous namespace)::BranchRelaxation::computeBlockSize(this=0x000000010f03fb60, MBB=0x000000010f8bbf28) const at BranchRelaxation.cpp:168:18
  frame #8: 0x0000000101f9b7be llc`(anonymous namespace)::BranchRelaxation::scanFunction(this=0x000000010f03fb60) at BranchRelaxation.cpp:158:39
  frame #9: 0x0000000101f9b264 llc`(anonymous namespace)::BranchRelaxation::runOnMachineFunction(this=0x000000010f03fb60, mf=0x000000010f0566f0) at BranchRelaxation.cpp:555:3

I'm replacing a G_MUL with an equivalent G_SHL here, is there an issue with doing this for AMDGPU?

Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D73659/new/

https://reviews.llvm.org/D73659