diff options
Diffstat (limited to 'lib/CodeGen/LowerSubregs.cpp')
| -rw-r--r-- | lib/CodeGen/LowerSubregs.cpp | 13 |
1 files changed, 7 insertions, 6 deletions
diff --git a/lib/CodeGen/LowerSubregs.cpp b/lib/CodeGen/LowerSubregs.cpp index 6c5052a068..f34b29041f 100644 --- a/lib/CodeGen/LowerSubregs.cpp +++ b/lib/CodeGen/LowerSubregs.cpp @@ -270,14 +270,15 @@ bool LowerSubregsInstructionPass::LowerInsert(MachineInstr *MI) { MachineBasicBlock::iterator CopyMI = MI; --CopyMI; + // INSERT_SUBREG is a two-address instruction so it implicitly kills SrcReg. + if (!MI->getOperand(1).isUndef()) + CopyMI->addOperand(MachineOperand::CreateReg(DstReg, false, true, true)); + // Transfer the kill/dead flags, if needed. if (MI->getOperand(0).isDead()) { TransferDeadFlag(MI, DstSubReg, TRI); - // Also add a SrcReg<imp-kill> of the super register. - CopyMI->addOperand(MachineOperand::CreateReg(DstReg, false, true, true)); - } else if (MI->getOperand(1).isUndef()) { - // If SrcReg was marked <undef> we must make sure it is alive after this - // replacement. Add a SrcReg<imp-def> operand. + } else { + // Make sure the full DstReg is live after this replacement. CopyMI->addOperand(MachineOperand::CreateReg(DstReg, true, true)); } @@ -293,7 +294,7 @@ bool LowerSubregsInstructionPass::LowerInsert(MachineInstr *MI) { DOUT << "\n"; MBB->erase(MI); - return true; + return true; } /// runOnMachineFunction - Reduce subregister inserts and extracts to register |