diff options
| -rw-r--r-- | lib/CodeGen/RegAllocGreedy.cpp | 13 | ||||
| -rw-r--r-- | lib/CodeGen/SplitKit.cpp | 2 | ||||
| -rw-r--r-- | lib/CodeGen/SplitKit.h | 8 |
3 files changed, 23 insertions, 0 deletions
diff --git a/lib/CodeGen/RegAllocGreedy.cpp b/lib/CodeGen/RegAllocGreedy.cpp index 7c461d8ea7..6feb45455d 100644 --- a/lib/CodeGen/RegAllocGreedy.cpp +++ b/lib/CodeGen/RegAllocGreedy.cpp @@ -1315,6 +1315,19 @@ unsigned RAGreedy::trySplit(LiveInterval &VirtReg, AllocationOrder &Order, SA->analyze(&VirtReg); + // FIXME: SplitAnalysis may repair broken live ranges coming from the + // coalescer. That may cause the range to become allocatable which means that + // tryRegionSplit won't be making progress. This check should be replaced with + // an assertion when the coalescer is fixed. + if (SA->didRepairRange()) { + // VirtReg has changed, so all cached queries are invalid. + Order.rewind(); + while (unsigned PhysReg = Order.next()) + query(VirtReg, PhysReg).clear(); + if (unsigned PhysReg = tryAssign(VirtReg, Order, NewVRegs)) + return PhysReg; + } + // First try to split around a region spanning multiple blocks. unsigned PhysReg = tryRegionSplit(VirtReg, Order, NewVRegs); if (PhysReg || !NewVRegs.empty()) diff --git a/lib/CodeGen/SplitKit.cpp b/lib/CodeGen/SplitKit.cpp index ac9d72bf62..feb3d3481b 100644 --- a/lib/CodeGen/SplitKit.cpp +++ b/lib/CodeGen/SplitKit.cpp @@ -51,6 +51,7 @@ void SplitAnalysis::clear() { UseBlocks.clear(); ThroughBlocks.clear(); CurLI = 0; + DidRepairRange = false; } SlotIndex SplitAnalysis::computeLastSplitPoint(unsigned Num) { @@ -119,6 +120,7 @@ void SplitAnalysis::analyzeUses() { if (!calcLiveBlockInfo()) { // FIXME: calcLiveBlockInfo found inconsistencies in the live range. // I am looking at you, SimpleRegisterCoalescing! + DidRepairRange = true; DEBUG(dbgs() << "*** Fixing inconsistent live interval! ***\n"); const_cast<LiveIntervals&>(LIS) .shrinkToUses(const_cast<LiveInterval*>(CurLI)); diff --git a/lib/CodeGen/SplitKit.h b/lib/CodeGen/SplitKit.h index 2ae760a58d..6305d0cc23 100644 --- a/lib/CodeGen/SplitKit.h +++ b/lib/CodeGen/SplitKit.h @@ -97,6 +97,9 @@ private: /// NumThroughBlocks - Number of live-through blocks. unsigned NumThroughBlocks; + /// DidRepairRange - analyze was forced to shrinkToUses(). + bool DidRepairRange; + SlotIndex computeLastSplitPoint(unsigned Num); // Sumarize statistics by counting instructions using CurLI. @@ -113,6 +116,11 @@ public: /// split. void analyze(const LiveInterval *li); + /// didRepairRange() - Returns true if CurLI was invalid and has been repaired + /// by analyze(). This really shouldn't happen, but sometimes the coalescer + /// can create live ranges that end in mid-air. + bool didRepairRange() const { return DidRepairRange; } + /// clear - clear all data structures so SplitAnalysis is ready to analyze a /// new interval. void clear(); |