diff options
| -rw-r--r-- | llvm/lib/CodeGen/LiveRegUnits.cpp | 29 |
1 files changed, 19 insertions, 10 deletions
diff --git a/llvm/lib/CodeGen/LiveRegUnits.cpp b/llvm/lib/CodeGen/LiveRegUnits.cpp index c9fa40e25d1..5ff27dd1aaf 100644 --- a/llvm/lib/CodeGen/LiveRegUnits.cpp +++ b/llvm/lib/CodeGen/LiveRegUnits.cpp @@ -17,21 +17,30 @@ #include "llvm/CodeGen/MachineInstrBundle.h" using namespace llvm; +/// Return true if the given MachineOperand clobbers the given register unit. +/// A register unit is only clobbered if all its super-registers are clobbered. +static bool operClobbersUnit(const MachineOperand *MO, unsigned Unit, + const MCRegisterInfo *MCRI) { + for (MCRegUnitRootIterator RI(Unit, MCRI); RI.isValid(); ++RI) { + for (MCSuperRegIterator SI(*RI, MCRI, true); SI.isValid(); ++SI) { + if (!MO->clobbersPhysReg(*SI)) + return false; + } + } + return true; +} + /// We assume the high bits of a physical super register are not preserved /// unless the instruction has an implicit-use operand reading the /// super-register or a register unit for the upper bits is available. void LiveRegUnits::removeRegsInMask(const MachineOperand &Op, const MCRegisterInfo &MCRI) { - const uint32_t *Mask = Op.getRegMask(); - unsigned Bit = 0; - for (unsigned R = 0; R < MCRI.getNumRegs(); ++R) { - if ((*Mask & (1u << Bit)) == 0) - removeReg(R, MCRI); - ++Bit; - if (Bit >= 32) { - Bit = 0; - ++Mask; - } + SparseSet<unsigned>::iterator LUI = LiveUnits.begin(); + while (LUI != LiveUnits.end()) { + if (operClobbersUnit(&Op, *LUI, &MCRI)) + LUI = LiveUnits.erase(LUI); + else + ++LUI; } } |
