diff --git a/lib/Target/ARM/ARMBaseInstrInfo.cpp b/lib/Target/ARM/ARMBaseInstrInfo.cpp index 0987e56852d..9231e6b1e32 100644 --- a/lib/Target/ARM/ARMBaseInstrInfo.cpp +++ b/lib/Target/ARM/ARMBaseInstrInfo.cpp @@ -629,9 +629,36 @@ void ARMBaseInstrInfo::copyPhysReg(MachineBasicBlock &MBB, bool SPRSrc = ARM::SPRRegClass.contains(SrcReg); unsigned Opc; - if (SPRDest && SPRSrc) + if (SPRDest && SPRSrc) { Opc = ARM::VMOVS; - else if (GPRDest && SPRSrc) + + // An even S-S copy may be feeding a NEON v2f32 instruction being used for + // f32 operations. In that case, it is better to copy the full D-regs with + // a VMOVD since that can be converted to a NEON-domain move by + // NEONMoveFix.cpp. Check that MI is the original COPY instruction, and + // that it really defines the whole D-register. + if ((DestReg - ARM::S0) % 2 == 0 && (SrcReg - ARM::S0) % 2 == 0 && + I != MBB.end() && I->isCopy() && + I->getOperand(0).getReg() == DestReg && + I->getOperand(1).getReg() == SrcReg) { + // I is pointing to the ortiginal COPY instruction. + // Find the parent D-registers. + const TargetRegisterInfo *TRI = &getRegisterInfo(); + unsigned SrcD = TRI->getMatchingSuperReg(SrcReg, ARM::ssub_0, + &ARM::DPRRegClass); + unsigned DestD = TRI->getMatchingSuperReg(DestReg, ARM::ssub_0, + &ARM::DPRRegClass); + // Be careful to not clobber an INSERT_SUBREG that reads and redefines a + // D-register. There must be an of destD, and no . + if (I->definesRegister(DestD, TRI) && !I->readsRegister(DestD, TRI)) { + Opc = ARM::VMOVD; + SrcReg = SrcD; + DestReg = DestD; + if (KillSrc) + KillSrc = I->killsRegister(SrcReg, TRI); + } + } + } else if (GPRDest && SPRSrc) Opc = ARM::VMOVRS; else if (SPRDest && GPRSrc) Opc = ARM::VMOVSR;