search for: anaylzephysreg

...is.Kills || Analysis.Clobbers) // Register killed, so isn't live. return LQR_Dead; is incorrect I think. A clobber isn't a full def, and so cannot be assumed to be a kill. Some bits from the live-in value may pass through into the live-out value. Looking into the code for anaylzePhysReg, I think the code looks like it intends for Defines to truly mean Reg or a super-register of Reg is defined, not any overlapping Reg is defined. The code looks like this: bool IsRegOrSuperReg = MOReg == Reg || TRI->isSuperRegister(MOReg, Reg); ... if (IsRegOrSuperReg) { PRI.Defines = true;...

...is.Kills || Analysis.Clobbers) // Register killed, so isn't live. return LQR_Dead; is incorrect I think. A clobber isn't a full def, and so cannot be assumed to be a kill. Some bits from the live-in value may pass through into the live-out value. Looking into the code for anaylzePhysReg, I think the code looks like it intends for Defines to truly mean Reg or a super-register of Reg is defined, not any overlapping Reg is defined. The code looks like this: bool IsRegOrSuperReg = MOReg == Reg || TRI->isSuperRegister(MOReg, Reg); ... if (IsRegOrSuperReg) { PRI.Defines = true;...

> On Dec 3, 2015, at 5:36 PM, Quentin Colombet via llvm-dev <llvm-dev at lists.llvm.org> wrote: > >> >> On Dec 3, 2015, at 5:11 PM, Smith, Kevin B <kevin.b.smith at intel.com <mailto:kevin.b.smith at intel.com>> wrote: >> >> >> >>> -----Original Message----- >>> From: Quentin Colombet [mailto:qcolombet at apple.com