/// The register tracker is unaware of global liveness so ignores normal
/// live-thru ranges. However, two-address or coalesced chains can also lead
/// to live ranges with no holes. Count these to inform heuristics that we
/// can never drop below this pressure.
void RegPressureTracker::initLiveThru(const RegPressureTracker &RPTracker) {
LiveThruPressure.assign(TRI->getNumRegPressureSets(), 0);
assert(isBottomClosed() && "need bottom-up tracking to intialize.");
for (const RegisterMaskPair &Pair : P.LiveOutRegs) {
unsigned RegUnit = Pair.RegUnit;
if (TargetRegisterInfo::isVirtualRegister(RegUnit)
&& !RPTracker.hasUntiedDef(RegUnit))
increaseSetPressure(LiveThruPressure, *MRI, RegUnit, 0, Pair.LaneMask);
}
}
/// The register tracker is unaware of global liveness so ignores normal
/// live-thru ranges. However, two-address or coalesced chains can also lead
/// to live ranges with no holes. Count these to inform heuristics that we
/// can never drop below this pressure.
void RegPressureTracker::initLiveThru(const RegPressureTracker &RPTracker) {
LiveThruPressure.assign(TRI->getNumRegPressureSets(), 0);
assert(isBottomClosed() && "need bottom-up tracking to intialize.");
for (unsigned i = 0, e = P.LiveOutRegs.size(); i < e; ++i) {
unsigned Reg = P.LiveOutRegs[i];
if (TargetRegisterInfo::isVirtualRegister(Reg)
&& !RPTracker.hasUntiedDef(Reg)) {
increaseSetPressure(LiveThruPressure, MRI->getPressureSets(Reg));
}
}
}