search for: use_nodbg_empty

...Regs for each basic block in a function. The function then loops through all instructions in a basic block and checks to see if it is a dead instruction. The check is whether it is a physical register or not with the check: TargetRegisterInfo::isPhysicalRegister(reg) ? LivePhysRegs[Reg] : !MRI->use_nodbg_empty(Reg) If the register is virtual, then MRI->use_nodbg_empty() returns false, if the register is physical LivePhysRegs[Reg] returns false, since the bitvector was inverted. So my instruction is considered dead and deleted. So, what I am trying to figure out is why this behavior is occurring? I d...

...ch basic block in a function. The function then loops through all instructions in a basic block and checks to see if it is a dead instruction. The check is whether it is a physical register or not with the check: > > TargetRegisterInfo::isPhysicalRegister(reg) ? LivePhysRegs[Reg] : !MRI->use_nodbg_empty(Reg) > > If the register is virtual, then MRI->use_nodbg_empty() returns false, if the register is physical LivePhysRegs[Reg] returns false, since the bitvector was inverted. So my instruction is considered dead and deleted. > Huh? The code is if (TargetRegisterInfo::isPhysic...

...Regs for each basic block in a function. The function then loops through all instructions in a basic block and checks to see if it is a dead instruction. The check is whether it is a physical register or not with the check: TargetRegisterInfo::isPhysicalRegister(reg) ? LivePhysRegs[Reg] : !MRI->use_nodbg_empty(Reg) If the register is virtual, then MRI->use_nodbg_empty() returns false, if the register is physical LivePhysRegs[Reg] returns false, since the bitvector was inverted. So my instruction is considered dead and deleted. Huh? The code is if (TargetRegisterInfo::isPhysicalRegister(Reg) ?...

...Regs for each basic block in a function. The function then loops through all instructions in a basic block and checks to see if it is a dead instruction. The check is whether it is a physical register or not with the check: TargetRegisterInfo::isPhysicalRegister(reg) ? LivePhysRegs[Reg] : !MRI->use_nodbg_empty(Reg) If the register is virtual, then MRI->use_nodbg_empty() returns false, if the register is physical LivePhysRegs[Reg] returns false, since the bitvector was inverted. So my instruction is considered dead and deleted. Huh? The code is if (TargetRegisterInfo::isPhysicalRegister(Reg) ?...

Hi, I wanted to see the non-debug uses of register 0 (Noreg) and so, I wrote the following piece of code. ***** MRI = &MF.getRegInfo(); if (!MRI->use_nodbg_empty(0)) { for (MachineRegisterInfo::use_nodbg_iterator ri = MRI->use_nodbg_begin(0), re = MRI->use_nodbg_end(); ri != re; ++ri) { MachineInstr *UseMI = &*ri; UseMI->dump (); } } ***** But I see that UseMI is DBG_VALUE %noreg, 0, !"foob...

...e). I get > those info by callings isDead or isDef function for that MachineOperand > (vreg). Is there a way to get more accurate liveness info? The absence of these flags does not mean anything, but if they are present, then they must be correct. You can always use functions use_empty and use_nodbg_empty, both in MachineRegisterInfo. A precise liveness information is calculated by Live Interval Analysis. -Krzysztof -- Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted by The Linux Foundation

Dear there, I am trying to use liveness of a variable while writing a machinefunction pass. But it seems that some virtual registers are not marked as dead while they should be (never used by anything else). I get those info by callings isDead or isDef function for that MachineOperand (vreg). Is there a way to get more accurate liveness info? Thanks, Xiaochu -------------- next part

...fo by callings isDead or isDef function for that MachineOperand >> (vreg). Is there a way to get more accurate liveness info? > > The absence of these flags does not mean anything, but if they are present, then they must be correct. > > You can always use functions use_empty and use_nodbg_empty, both in MachineRegisterInfo. A precise liveness information is calculated by Live Interval Analysis. > > -Krzysztof > > > -- > Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted by The Linux Foundation > _____________________________________________...