lib/CodeGen/CriticalAntiDepBreaker.cpp

303 // be replaced by NewReg. Return true if any of their parent instructions may
308 // the two-address instruction also defines NewReg, as may happen with
312 // both NewReg and AntiDepReg covers it.
316                                                 unsigned NewReg)
322     // operands, in case they may be assigned to NewReg. In this case antidep
327     // Handle cases in which this instructions defines NewReg.
332       if (CheckOper.isRegMask() && CheckOper.clobbersPhysReg(NewReg))
336           CheckOper.getReg() != NewReg)
339       // Don't allow the instruction to define NewReg and AntiDepReg.
345       // NewReg
349       // Don't allow inline asm to define NewReg at all. Who know what it's
368     unsigned NewReg = Order[i];
370     if (NewReg == AntiDepReg) continue;
374     if (NewReg == LastNewReg) continue;
375     // If any instructions that define AntiDepReg also define the NewReg, it's
378     if (isNewRegClobberedByRefs(RegRefBegin, RegRefEnd, NewReg)) continue;
379     // If NewReg is dead and NewReg's most recent def is not before
380     // AntiDepReg's kill, it's safe to replace AntiDepReg with NewReg.
383     assert(((KillIndices[NewReg] == ~0u) != (DefIndices[NewReg] == ~0u))
384            && "Kill and Def maps aren't consistent for NewReg!");
385     if (KillIndices[NewReg] != ~0u ||
386         Classes[NewReg] == reinterpret_cast<TargetRegisterClass *>(-1) ||
387         KillIndices[AntiDepReg] > DefIndices[NewReg])
389     // If NewReg overlaps any of the forbidden registers, we can't use it.
393       if (TRI->regsOverlap(NewReg, *it)) {
398     return NewReg;
606       if (unsigned NewReg = findSuitableFreeRegister(Range.first, Range.second,
613               << " using " << TRI->getName(NewReg) << "!\n");
619           Q->second->setReg(NewReg);
628               UpdateDbgValue(DVI->first, AntiDepReg, NewReg);
634         Classes[NewReg] = Classes[AntiDepReg];
635         DefIndices[NewReg] = DefIndices[AntiDepReg];
636         KillIndices[NewReg] = KillIndices[AntiDepReg];
637         assert(((KillIndices[NewReg] == ~0u) !=
638                 (DefIndices[NewReg] == ~0u)) &&
639              "Kill and Def maps aren't consistent for NewReg!");
649         LastNewReg[AntiDepReg] = NewReg;