#include "SpillPlacement.h"
#include "SplitKit.h"
#include "VirtRegMap.h"
-#include "RegisterCoalescer.h"
#include "llvm/ADT/Statistic.h"
#include "llvm/Analysis/AliasAnalysis.h"
#include "llvm/Function.h"
STATISTIC(NumLocalSplits, "Number of split local live ranges");
STATISTIC(NumEvicted, "Number of interferences evicted");
-cl::opt<bool> CompactRegions("compact-regions", cl::init(true));
+static cl::opt<SplitEditor::ComplementSpillMode>
+SplitSpillMode("split-spill-mode", cl::Hidden,
+ cl::desc("Spill mode for splitting live ranges"),
+ cl::values(clEnumValN(SplitEditor::SM_Partition, "default", "Default"),
+ clEnumValN(SplitEditor::SM_Size, "size", "Optimize for size"),
+ clEnumValN(SplitEditor::SM_Speed, "speed", "Optimize for speed"),
+ clEnumValEnd),
+ cl::init(SplitEditor::SM_Partition));
static RegisterRegAlloc greedyRegAlloc("greedy", "greedy register allocator",
createGreedyRegisterAllocator);
SmallVectorImpl<LiveInterval*>&, unsigned = ~0u);
unsigned tryRegionSplit(LiveInterval&, AllocationOrder&,
SmallVectorImpl<LiveInterval*>&);
+ unsigned tryBlockSplit(LiveInterval&, AllocationOrder&,
+ SmallVectorImpl<LiveInterval*>&);
unsigned tryLocalSplit(LiveInterval&, AllocationOrder&,
SmallVectorImpl<LiveInterval*>&);
unsigned trySplit(LiveInterval&, AllocationOrder&,
AU.addPreserved<LiveDebugVariables>();
if (StrongPHIElim)
AU.addRequiredID(StrongPHIEliminationID);
- AU.addRequiredTransitive<RegisterCoalescer>();
+ AU.addRequiredTransitiveID(RegisterCoalescerPassID);
AU.addRequired<CalculateSpillWeights>();
AU.addRequired<LiveStacks>();
AU.addPreserved<LiveStacks>();
}
void RAGreedy::LRE_DidCloneVirtReg(unsigned New, unsigned Old) {
+ // Cloning a register we haven't even heard about yet? Just ignore it.
+ if (!ExtraRegInfo.inBounds(Old))
+ return;
+
// LRE may clone a virtual register because dead code elimination causes it to
// be split into connected components. The new components are much smaller
// than the original, so they should get a new chance at being assigned.
if (ExtraRegInfo[Reg].Stage == RS_Split) {
// Unsplit ranges that couldn't be allocated immediately are deferred until
- // everything else has been allocated. Long ranges are allocated last so
- // they are split against realistic interference.
- if (CompactRegions)
- Prio = Size;
- else
- Prio = (1u << 31) - Size;
+ // everything else has been allocated.
+ Prio = Size;
} else {
- // Everything else is allocated in long->short order. Long ranges that don't
- // fit should be spilled ASAP so they don't create interference.
+ // Everything is allocated in long->short order. Long ranges that don't fit
+ // should be spilled (or split) ASAP so they don't create interference.
Prio = (1u << 31) + Size;
// Boost ranges that have a physical register hint.
assert(NumGlobalIntvs && "No global intervals configured");
// Isolate even single instructions when dealing with a proper sub-class.
- // That giarantees register class inflation for the stack interval because it
+ // That guarantees register class inflation for the stack interval because it
// is all copies.
unsigned Reg = SA->getParent().reg;
bool SingleInstrs = RegClassInfo.isProperSubClass(MRI->getRegClass(Reg));
SmallVector<unsigned, 8> IntvMap;
SE->finish(&IntvMap);
- DebugVars->splitRegister(SA->getParent().reg, LREdit.regs());
+ DebugVars->splitRegister(Reg, LREdit.regs());
ExtraRegInfo.resize(MRI->getNumVirtRegs());
unsigned OrigBlocks = SA->getNumLiveBlocks();
SmallVector<unsigned, 8> UsedCands;
// Check if we can split this live range around a compact region.
- bool HasCompact = CompactRegions && calcCompactRegion(GlobalCand.front());
+ bool HasCompact = calcCompactRegion(GlobalCand.front());
if (HasCompact) {
// Yes, keep GlobalCand[0] as the compact region candidate.
NumCands = 1;
// Prepare split editor.
LiveRangeEdit LREdit(VirtReg, NewVRegs, this);
- SE->reset(LREdit);
+ SE->reset(LREdit, SplitSpillMode);
// Assign all edge bundles to the preferred candidate, or NoCand.
BundleCand.assign(Bundles->getNumBundles(), NoCand);
}
+//===----------------------------------------------------------------------===//
+// Per-Block Splitting
+//===----------------------------------------------------------------------===//
+
+/// tryBlockSplit - Split a global live range around every block with uses. This
+/// creates a lot of local live ranges, that will be split by tryLocalSplit if
+/// they don't allocate.
+unsigned RAGreedy::tryBlockSplit(LiveInterval &VirtReg, AllocationOrder &Order,
+ SmallVectorImpl<LiveInterval*> &NewVRegs) {
+ assert(&SA->getParent() == &VirtReg && "Live range wasn't analyzed");
+ unsigned Reg = VirtReg.reg;
+ bool SingleInstrs = RegClassInfo.isProperSubClass(MRI->getRegClass(Reg));
+ LiveRangeEdit LREdit(VirtReg, NewVRegs, this);
+ SE->reset(LREdit, SplitSpillMode);
+ ArrayRef<SplitAnalysis::BlockInfo> UseBlocks = SA->getUseBlocks();
+ for (unsigned i = 0; i != UseBlocks.size(); ++i) {
+ const SplitAnalysis::BlockInfo &BI = UseBlocks[i];
+ if (SA->shouldSplitSingleBlock(BI, SingleInstrs))
+ SE->splitSingleBlock(BI);
+ }
+ // No blocks were split.
+ if (LREdit.empty())
+ return 0;
+
+ // We did split for some blocks.
+ SmallVector<unsigned, 8> IntvMap;
+ SE->finish(&IntvMap);
+
+ // Tell LiveDebugVariables about the new ranges.
+ DebugVars->splitRegister(Reg, LREdit.regs());
+
+ ExtraRegInfo.resize(MRI->getNumVirtRegs());
+
+ // Sort out the new intervals created by splitting. The remainder interval
+ // goes straight to spilling, the new local ranges get to stay RS_New.
+ for (unsigned i = 0, e = LREdit.size(); i != e; ++i) {
+ LiveInterval &LI = *LREdit.get(i);
+ if (getStage(LI) == RS_New && IntvMap[i] == 0)
+ setStage(LI, RS_Spill);
+ }
+
+ if (VerifyEnabled)
+ MF->verify(this, "After splitting live range around basic blocks");
+ return 0;
+}
+
//===----------------------------------------------------------------------===//
// Local Splitting
//===----------------------------------------------------------------------===//
/// @return Physreg when VirtReg may be assigned and/or new NewVRegs.
unsigned RAGreedy::trySplit(LiveInterval &VirtReg, AllocationOrder &Order,
SmallVectorImpl<LiveInterval*>&NewVRegs) {
+ // Ranges must be Split2 or less.
+ if (getStage(VirtReg) >= RS_Spill)
+ return 0;
+
// Local intervals are handled separately.
if (LIS->intervalIsInOneMBB(VirtReg)) {
NamedRegionTimer T("Local Splitting", TimerGroupName, TimePassesIsEnabled);
NamedRegionTimer T("Global Splitting", TimerGroupName, TimePassesIsEnabled);
- // Ranges must be Split2 or less.
- if (getStage(VirtReg) >= RS_Spill)
- return 0;
-
SA->analyze(&VirtReg);
// FIXME: SplitAnalysis may repair broken live ranges coming from the
return PhysReg;
}
- // Then isolate blocks with multiple uses.
- SplitAnalysis::BlockPtrSet Blocks;
- if (SA->getMultiUseBlocks(Blocks)) {
- LiveRangeEdit LREdit(VirtReg, NewVRegs, this);
- SE->reset(LREdit);
- SE->splitSingleBlocks(Blocks);
- setStage(NewVRegs.begin(), NewVRegs.end(), RS_Spill);
- if (VerifyEnabled)
- MF->verify(this, "After splitting live range around basic blocks");
- }
-
- // Don't assign any physregs.
- return 0;
+ // Then isolate blocks.
+ return tryBlockSplit(VirtReg, Order, NewVRegs);
}