diff options
Diffstat (limited to 'llvm/lib/CodeGen/SplitKit.cpp')
| -rw-r--r-- | llvm/lib/CodeGen/SplitKit.cpp | 31 |
1 files changed, 26 insertions, 5 deletions
diff --git a/llvm/lib/CodeGen/SplitKit.cpp b/llvm/lib/CodeGen/SplitKit.cpp index f270c3a..140a91ae 100644 --- a/llvm/lib/CodeGen/SplitKit.cpp +++ b/llvm/lib/CodeGen/SplitKit.cpp @@ -1352,13 +1352,34 @@ void SplitEditor::rewriteAssigned(bool ExtendRanges) { continue; // We may want to extend a live range for a partial redef, or for a use // tied to an early clobber. - Idx = Idx.getPrevSlot(); - if (!Edit->getParent().liveAt(Idx)) + if (!Edit->getParent().liveAt(Idx.getPrevSlot())) continue; - } else - Idx = Idx.getRegSlot(true); + } else { + assert(MO.isUse()); + bool IsEarlyClobber = false; + if (MO.isTied()) { + // We want to extend a live range into `e` slot rather than `r` slot if + // tied-def is early clobber, because the `e` slot already contained + // in the live range of early-clobber tied-def operand, give an example + // here: + // 0 %0 = ... + // 16 early-clobber %0 = Op %0 (tied-def 0), ... + // 32 ... = Op %0 + // Before extend: + // %0 = [0r, 0d) [16e, 32d) + // The point we want to extend is 0d to 16e not 16r in this case, but if + // we use 16r here we will extend nothing because that already contained + // in [16e, 32d). + unsigned OpIdx = MI->getOperandNo(&MO); + unsigned DefOpIdx = MI->findTiedOperandIdx(OpIdx); + const MachineOperand &DefOp = MI->getOperand(DefOpIdx); + IsEarlyClobber = DefOp.isEarlyClobber(); + } + + Idx = Idx.getRegSlot(IsEarlyClobber); + } - SlotIndex Next = Idx.getNextSlot(); + SlotIndex Next = Idx; if (LI.hasSubRanges()) { // We have to delay extending subranges until we have seen all operands // defining the register. This is because a <def,read-undef> operand |