Check proper live range in extendPHIRanges
The function extendPHIRanges checks the main range of the original live
interval, even when dealing with a subrange. This could also lead to an
assert when the subrange is not live at the extension point, but the
main range is. To avoid this, check the corresponding subrange of the
original live range, instead of always checking the main range.
Review (as a part of a bigger set of changes):
https://reviews.llvm.org/D26359
llvm-svn: 287571
diff --git a/llvm/lib/CodeGen/SplitKit.cpp b/llvm/lib/CodeGen/SplitKit.cpp
index 2d5a9d6..b881c6d 100644
--- a/llvm/lib/CodeGen/SplitKit.cpp
+++ b/llvm/lib/CodeGen/SplitKit.cpp
@@ -1092,13 +1092,19 @@
}
void SplitEditor::extendPHIRange(MachineBasicBlock &B, LiveRangeCalc &LRC,
- LiveRange &LR, ArrayRef<SlotIndex> Undefs) {
+ LiveRange &LR, LaneBitmask LM,
+ ArrayRef<SlotIndex> Undefs) {
for (MachineBasicBlock *P : B.predecessors()) {
SlotIndex End = LIS.getMBBEndIdx(P);
SlotIndex LastUse = End.getPrevSlot();
// The predecessor may not have a live-out value. That is OK, like an
// undef PHI operand.
- if (Edit->getParent().liveAt(LastUse))
+ LiveInterval &PLI = Edit->getParent();
+ // Need the cast because the inputs to ?: would otherwise be deemed
+ // "incompatible": SubRange vs LiveInterval.
+ LiveRange &PSR = (LM != ~0u) ? getSubRangeForMask(LM, PLI)
+ : static_cast<LiveRange&>(PLI);
+ if (PSR.liveAt(LastUse))
LRC.extend(LR, End, /*PhysReg=*/0, Undefs);
}
}
@@ -1120,7 +1126,7 @@
LiveRangeCalc &LRC = getLRCalc(RegIdx);
MachineBasicBlock &B = *LIS.getMBBFromIndex(V->def);
if (!removeDeadSegment(V->def, LI))
- extendPHIRange(B, LRC, LI, /*Undefs=*/{});
+ extendPHIRange(B, LRC, LI, ~0u, /*Undefs=*/{});
}
SmallVector<SlotIndex, 4> Undefs;
@@ -1141,7 +1147,7 @@
&LIS.getVNInfoAllocator());
Undefs.clear();
LI.computeSubRangeUndefs(Undefs, PS.LaneMask, MRI, *LIS.getSlotIndexes());
- extendPHIRange(B, SubLRC, S, Undefs);
+ extendPHIRange(B, SubLRC, S, PS.LaneMask, Undefs);
}
}
}