diff options
Diffstat (limited to 'lib/Target/AArch64/AArch64InstrInfo.cpp')
| -rw-r--r-- | lib/Target/AArch64/AArch64InstrInfo.cpp | 45 |
1 files changed, 45 insertions, 0 deletions
diff --git a/lib/Target/AArch64/AArch64InstrInfo.cpp b/lib/Target/AArch64/AArch64InstrInfo.cpp index ce85b2c..b702275 100644 --- a/lib/Target/AArch64/AArch64InstrInfo.cpp +++ b/lib/Target/AArch64/AArch64InstrInfo.cpp @@ -541,6 +541,51 @@ void AArch64InstrInfo::insertSelect(MachineBasicBlock &MBB, CC); } +// FIXME: this implementation should be micro-architecture dependent, so a +// micro-architecture target hook should be introduced here in future. +bool AArch64InstrInfo::isAsCheapAsAMove(const MachineInstr *MI) const { + if (!Subtarget.isCortexA57() && !Subtarget.isCortexA53()) + return MI->isAsCheapAsAMove(); + + switch (MI->getOpcode()) { + default: + return false; + + // add/sub on register without shift + case AArch64::ADDWri: + case AArch64::ADDXri: + case AArch64::SUBWri: + case AArch64::SUBXri: + return (MI->getOperand(3).getImm() == 0); + + // logical ops on immediate + case AArch64::ANDWri: + case AArch64::ANDXri: + case AArch64::EORWri: + case AArch64::EORXri: + case AArch64::ORRWri: + case AArch64::ORRXri: + return true; + + // logical ops on register without shift + case AArch64::ANDWrr: + case AArch64::ANDXrr: + case AArch64::BICWrr: + case AArch64::BICXrr: + case AArch64::EONWrr: + case AArch64::EONXrr: + case AArch64::EORWrr: + case AArch64::EORXrr: + case AArch64::ORNWrr: + case AArch64::ORNXrr: + case AArch64::ORRWrr: + case AArch64::ORRXrr: + return true; + } + + llvm_unreachable("Unknown opcode to check as cheap as a move!"); +} + bool AArch64InstrInfo::isCoalescableExtInstr(const MachineInstr &MI, unsigned &SrcReg, unsigned &DstReg, unsigned &SubIdx) const { |