diff options
Diffstat (limited to 'lib/CodeGen/TwoAddressInstructionPass.cpp')
| -rw-r--r-- | lib/CodeGen/TwoAddressInstructionPass.cpp | 10 |
1 files changed, 9 insertions, 1 deletions
diff --git a/lib/CodeGen/TwoAddressInstructionPass.cpp b/lib/CodeGen/TwoAddressInstructionPass.cpp index dfd258d592..d879378222 100644 --- a/lib/CodeGen/TwoAddressInstructionPass.cpp +++ b/lib/CodeGen/TwoAddressInstructionPass.cpp @@ -177,6 +177,10 @@ char &llvm::TwoAddressInstructionPassID = TwoAddressInstructionPass::ID; bool TwoAddressInstructionPass::Sink3AddrInstruction(MachineBasicBlock *MBB, MachineInstr *MI, unsigned SavedReg, MachineBasicBlock::iterator OldPos) { + // FIXME: Shouldn't we be trying to do this before we three-addressify the + // instruction? After this transformation is done, we no longer need + // the instruction to be in three-address form. + // Check if it's safe to move this instruction. bool SeenStore = true; // Be conservative. if (!MI->isSafeToMove(TII, AA, SeenStore)) @@ -217,7 +221,11 @@ bool TwoAddressInstructionPass::Sink3AddrInstruction(MachineBasicBlock *MBB, break; } - if (!KillMI || KillMI->getParent() != MBB || KillMI == MI) + // If we find the instruction that kills SavedReg, and it is in an + // appropriate location, we can try to sink the current instruction + // past it. + if (!KillMI || KillMI->getParent() != MBB || KillMI == MI || + KillMI->getDesc().isTerminator()) return false; // If any of the definitions are used by another instruction between the |