diff options
Diffstat (limited to 'lib/CodeGen/TargetSchedule.cpp')
| -rw-r--r-- | lib/CodeGen/TargetSchedule.cpp | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/lib/CodeGen/TargetSchedule.cpp b/lib/CodeGen/TargetSchedule.cpp index 53cd11c5da..64ee9d1c46 100644 --- a/lib/CodeGen/TargetSchedule.cpp +++ b/lib/CodeGen/TargetSchedule.cpp @@ -201,7 +201,10 @@ unsigned TargetSchedModel::computeOperandLatency( if (UseDesc->NumReadAdvanceEntries == 0) return Latency; unsigned UseIdx = findUseIdx(UseMI, UseOperIdx); - return Latency - STI->getReadAdvanceCycles(UseDesc, UseIdx, WriteID); + int Advance = STI->getReadAdvanceCycles(UseDesc, UseIdx, WriteID); + if (Advance > 0 && (unsigned)Advance > Latency) // unsigned wrap + return 0; + return Latency - Advance; } // If DefIdx does not exist in the model (e.g. implicit defs), then return // unit latency (defaultDefLatency may be too conservative). |