diff options
Diffstat (limited to 'llvm/lib/CodeGen/MachineScheduler.cpp')
| -rw-r--r-- | llvm/lib/CodeGen/MachineScheduler.cpp | 16 |
1 files changed, 15 insertions, 1 deletions
diff --git a/llvm/lib/CodeGen/MachineScheduler.cpp b/llvm/lib/CodeGen/MachineScheduler.cpp index f40e918..f6d03f5 100644 --- a/llvm/lib/CodeGen/MachineScheduler.cpp +++ b/llvm/lib/CodeGen/MachineScheduler.cpp @@ -4275,6 +4275,12 @@ unsigned ResourceSegments::getFirstAvailableAt( assert(std::is_sorted(std::begin(_Intervals), std::end(_Intervals), sortIntervals) && "Cannot execute on an un-sorted set of intervals."); + + // Zero resource usage is allowed by TargetSchedule.td but we do not construct + // a ResourceSegment interval for that situation. + if (AcquireAtCycle == Cycle) + return CurrCycle; + unsigned RetCycle = CurrCycle; ResourceSegments::IntervalTy NewInterval = IntervalBuilder(RetCycle, AcquireAtCycle, ReleaseAtCycle); @@ -4294,8 +4300,16 @@ unsigned ResourceSegments::getFirstAvailableAt( void ResourceSegments::add(ResourceSegments::IntervalTy A, const unsigned CutOff) { - assert(A.first < A.second && "Cannot add empty resource usage"); + assert(A.first <= A.second && "Cannot add negative resource usage"); assert(CutOff > 0 && "0-size interval history has no use."); + // Zero resource usage is allowed by TargetSchedule.td, in the case that the + // instruction needed the resource to be available but does not use it. + // However, ResourceSegment represents an interval that is closed on the left + // and open on the right. It is impossible to represent an empty interval when + // the left is closed. Do not add it to Intervals. + if (A.first == A.second) + return; + assert(all_of(_Intervals, [&A](const ResourceSegments::IntervalTy &Interval) -> bool { return !intersects(A, Interval); |