diff options
Diffstat (limited to 'lib/Target/X86')
| -rw-r--r-- | lib/Target/X86/X86ISelLowering.cpp | 28 |
1 files changed, 22 insertions, 6 deletions
diff --git a/lib/Target/X86/X86ISelLowering.cpp b/lib/Target/X86/X86ISelLowering.cpp index 0952350d07..9727de8203 100644 --- a/lib/Target/X86/X86ISelLowering.cpp +++ b/lib/Target/X86/X86ISelLowering.cpp @@ -13001,8 +13001,8 @@ X86TargetLowering::EmitAtomicLoadArith(MachineInstr *MI, MachineBasicBlock *origMainMBB = mainMBB; // Add a PHI. - BuildMI(mainMBB, DL, TII->get(X86::PHI), t4) - .addReg(t1).addMBB(thisMBB).addReg(t3).addMBB(mainMBB); + MachineInstr *Phi = BuildMI(mainMBB, DL, TII->get(X86::PHI), t4) + .addReg(t1).addMBB(thisMBB).addReg(t3).addMBB(mainMBB); unsigned Opc = MI->getOpcode(); switch (Opc) { @@ -13105,6 +13105,11 @@ X86TargetLowering::EmitAtomicLoadArith(MachineInstr *MI, .addReg(SrcReg).addReg(t4) .addImm(CC); mainMBB = EmitLoweredSelect(MIB, mainMBB); + // Replace the original PHI node as mainMBB is changed after CMOV + // lowering. + BuildMI(*origMainMBB, Phi, DL, TII->get(X86::PHI), t4) + .addReg(t1).addMBB(thisMBB).addReg(t3).addMBB(mainMBB); + Phi->eraseFromParent(); } break; } @@ -13298,10 +13303,10 @@ X86TargetLowering::EmitAtomicLoadArith6432(MachineInstr *MI, MachineBasicBlock *origMainMBB = mainMBB; // Add PHIs. - BuildMI(mainMBB, DL, TII->get(X86::PHI), t4L) - .addReg(t1L).addMBB(thisMBB).addReg(t3L).addMBB(mainMBB); - BuildMI(mainMBB, DL, TII->get(X86::PHI), t4H) - .addReg(t1H).addMBB(thisMBB).addReg(t3H).addMBB(mainMBB); + MachineInstr *PhiL = BuildMI(mainMBB, DL, TII->get(X86::PHI), t4L) + .addReg(t1L).addMBB(thisMBB).addReg(t3L).addMBB(mainMBB); + MachineInstr *PhiH = BuildMI(mainMBB, DL, TII->get(X86::PHI), t4H) + .addReg(t1H).addMBB(thisMBB).addReg(t3H).addMBB(mainMBB); unsigned Opc = MI->getOpcode(); switch (Opc) { @@ -13375,10 +13380,21 @@ X86TargetLowering::EmitAtomicLoadArith6432(MachineInstr *MI, .addReg(SrcLoReg).addReg(t4L) .addImm(X86::COND_NE); mainMBB = EmitLoweredSelect(MIB, mainMBB); + // As the lowered CMOV won't clobber EFLAGS, we could reuse it for the + // 2nd CMOV lowering. + mainMBB->addLiveIn(X86::EFLAGS); MIB = BuildMI(mainMBB, DL, TII->get(X86::CMOV_GR32), t2H) .addReg(SrcHiReg).addReg(t4H) .addImm(X86::COND_NE); mainMBB = EmitLoweredSelect(MIB, mainMBB); + // Replace the original PHI node as mainMBB is changed after CMOV + // lowering. + BuildMI(*origMainMBB, PhiL, DL, TII->get(X86::PHI), t4L) + .addReg(t1L).addMBB(thisMBB).addReg(t3L).addMBB(mainMBB); + BuildMI(*origMainMBB, PhiH, DL, TII->get(X86::PHI), t4H) + .addReg(t1H).addMBB(thisMBB).addReg(t3H).addMBB(mainMBB); + PhiL->eraseFromParent(); + PhiH->eraseFromParent(); } break; } |