Page MenuHomePhabricator
Differential D16831 Diff 46819 lib/CodeGen/CalcSpillWeights.cpp

Changeset View

Standalone View

View Options

lib/CodeGen/CalcSpillWeights.cpp

Show First 20 Lines • Show All 207 Lines • ▼ Show 20 Lines if (unsigned hint = hintPhys ? hintPhys : hintVirt) {
// Weakly boost the spill weight of hinted registers. // Weakly boost the spill weight of hinted registers.
totalWeight *= 1.01F; totalWeight *= 1.01F;
} }
// If the live interval was already unspillable, leave it that way. // If the live interval was already unspillable, leave it that way.
if (!Spillable) if (!Spillable)
return; return;
// Mark li as unspillable if all live ranges are tiny. // Mark li as unspillable if all live ranges are tiny and the interval
if (li.isZeroLength(LIS.getSlotIndexes())) { // does not contain any reg masks (which may require spilling).
if (li.isZeroLength(LIS.getSlotIndexes()) &&
!li.containsRegMask(LIS.getRegMaskSlots())) {
li.markNotSpillable(); li.markNotSpillable();
return; return;
} }
// If all of the definitions of the interval are re-materializable, // If all of the definitions of the interval are re-materializable,
// it is a preferred candidate for spilling. // it is a preferred candidate for spilling.
// FIXME: this gets much more complicated once we support non-trivial // FIXME: this gets much more complicated once we support non-trivial
// re-materialization. // re-materialization.
if (isRematerializable(li, LIS, VRM, *MF.getSubtarget().getInstrInfo())) if (isRematerializable(li, LIS, VRM, *MF.getSubtarget().getInstrInfo()))
totalWeight *= 0.5F; totalWeight *= 0.5F;
li.weight = normalize(totalWeight, li.getSize(), numInstr); li.weight = normalize(totalWeight, li.getSize(), numInstr);
} }