search for: shamt_virtreg

...t like this: ... R3 = outval_virtreg ... blr So the copy and blr are flagged together. Another case where flags are useful are for things like the X86 variable shift instruction. There the shift amount is required to be in the CL register, so we generate code like this: CL = shamt_virtreg X = shl Y, CL We don't want the copy and shift to wander apart from each other (e.g. we don't want another shift to get scheduled in between them), so we flag them together. In practice, these copies usually get coallesced away. -Chris -- http://nondot.org/sabre/ http://llvm.org/

I have changed the way in which the ARM backend generates a function return. Instead of expanding a RET to a CopyToReg;RETFLAG, it now expands into a CopyToReg;BRIND. I haven't commit it yet, but the patch is attached. In my opinion the resulting code is easier to understand, but I have some questions: Why all backends use RETFLAG? Why it is named RETFLAG? Why the Copy that places the

...... > blr > > So the copy and blr are flagged together. > > Another case where flags are useful are for things like the X86 variable > shift instruction. There the shift amount is required to be in the CL > register, so we generate code like this: > > > CL = shamt_virtreg > X = shl Y, CL > > We don't want the copy and shift to wander apart from each other (e.g. we > don't want another shift to get scheduled in between them), so we flag > them together. In practice, these copies usually get coallesced away. In the second case shl explicitl...