diff options
Diffstat (limited to 'llvm/lib/Target/AArch64/AArch64LoadStoreOptimizer.cpp')
| -rw-r--r-- | llvm/lib/Target/AArch64/AArch64LoadStoreOptimizer.cpp | 13 |
1 files changed, 13 insertions, 0 deletions
diff --git a/llvm/lib/Target/AArch64/AArch64LoadStoreOptimizer.cpp b/llvm/lib/Target/AArch64/AArch64LoadStoreOptimizer.cpp index 3156bb446963..bc91d628f0b4 100644 --- a/llvm/lib/Target/AArch64/AArch64LoadStoreOptimizer.cpp +++ b/llvm/lib/Target/AArch64/AArch64LoadStoreOptimizer.cpp @@ -1325,6 +1325,19 @@ canRenameUpToDef(MachineInstr &FirstMI, LiveRegUnits &UsedInBetween, // For defs, check if we can rename the first def of RegToRename. if (FoundDef) { + // For some pseudo instructions, we might not generate code in the end + // (e.g. KILL) and we would end up without a correct def for the rename + // register. + // TODO: This might be overly conservative and we could handle those cases + // in multiple ways: + // 1. Insert an extra copy, to materialize the def. + // 2. Skip pseudo-defs until we find an non-pseudo def. + if (MI.isPseudo()) { + LLVM_DEBUG(dbgs() << " Cannot rename pseudo instruction " << MI + << "\n"); + return false; + } + for (auto &MOP : MI.operands()) { if (!MOP.isReg() || !MOP.isDef() || MOP.isDebug() || !MOP.getReg() || !TRI->regsOverlap(MOP.getReg(), RegToRename)) |