diff options
Diffstat (limited to 'llvm/lib')
| -rw-r--r-- | llvm/lib/CodeGen/RegisterCoalescer.cpp | 11 |
1 files changed, 9 insertions, 2 deletions
diff --git a/llvm/lib/CodeGen/RegisterCoalescer.cpp b/llvm/lib/CodeGen/RegisterCoalescer.cpp index 59e2e85f29e..a3f75d82d0e 100644 --- a/llvm/lib/CodeGen/RegisterCoalescer.cpp +++ b/llvm/lib/CodeGen/RegisterCoalescer.cpp @@ -1733,8 +1733,15 @@ void RegisterCoalescer::updateRegDefsUses(unsigned SrcReg, unsigned DstReg, if (SubIdx != 0 && MO.isUse() && MRI->shouldTrackSubRegLiveness(DstReg)) { if (!DstInt->hasSubRanges()) { BumpPtrAllocator &Allocator = LIS->getVNInfoAllocator(); - LaneBitmask Mask = MRI->getMaxLaneMaskForVReg(DstInt->reg); - DstInt->createSubRangeFrom(Allocator, Mask, *DstInt); + LaneBitmask FullMask = MRI->getMaxLaneMaskForVReg(DstInt->reg); + LaneBitmask UsedLanes = TRI->getSubRegIndexLaneMask(SubIdx); + LaneBitmask UnusedLanes = FullMask & ~UsedLanes; + DstInt->createSubRangeFrom(Allocator, UsedLanes, *DstInt); + // The unused lanes are just empty live-ranges at this point. + // It is the caller responsibility to set the proper + // dead segments if there is an actual dead def of the + // unused lanes. This may happen with rematerialization. + DstInt->createSubRange(Allocator, UnusedLanes); } SlotIndex MIIdx = UseMI->isDebugValue() ? LIS->getSlotIndexes()->getIndexBefore(*UseMI) |
