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-rw-r--r--lib/CodeGen/SplitKit.cpp85
1 files changed, 52 insertions, 33 deletions
diff --git a/lib/CodeGen/SplitKit.cpp b/lib/CodeGen/SplitKit.cpp
index 63627800af69..9959f74d5f27 100644
--- a/lib/CodeGen/SplitKit.cpp
+++ b/lib/CodeGen/SplitKit.cpp
@@ -14,10 +14,10 @@
#define DEBUG_TYPE "regalloc"
#include "SplitKit.h"
-#include "LiveRangeEdit.h"
#include "VirtRegMap.h"
#include "llvm/ADT/Statistic.h"
#include "llvm/CodeGen/LiveIntervalAnalysis.h"
+#include "llvm/CodeGen/LiveRangeEdit.h"
#include "llvm/CodeGen/MachineDominators.h"
#include "llvm/CodeGen/MachineInstrBuilder.h"
#include "llvm/CodeGen/MachineLoopInfo.h"
@@ -62,13 +62,14 @@ SlotIndex SplitAnalysis::computeLastSplitPoint(unsigned Num) {
const MachineBasicBlock *MBB = MF.getBlockNumbered(Num);
const MachineBasicBlock *LPad = MBB->getLandingPadSuccessor();
std::pair<SlotIndex, SlotIndex> &LSP = LastSplitPoint[Num];
+ SlotIndex MBBEnd = LIS.getMBBEndIdx(MBB);
// Compute split points on the first call. The pair is independent of the
// current live interval.
if (!LSP.first.isValid()) {
MachineBasicBlock::const_iterator FirstTerm = MBB->getFirstTerminator();
if (FirstTerm == MBB->end())
- LSP.first = LIS.getMBBEndIdx(MBB);
+ LSP.first = MBBEnd;
else
LSP.first = LIS.getInstructionIndex(FirstTerm);
@@ -80,7 +81,7 @@ SlotIndex SplitAnalysis::computeLastSplitPoint(unsigned Num) {
for (MachineBasicBlock::const_iterator I = MBB->end(), E = MBB->begin();
I != E;) {
--I;
- if (I->getDesc().isCall()) {
+ if (I->isCall()) {
LSP.second = LIS.getInstructionIndex(I);
break;
}
@@ -89,10 +90,32 @@ SlotIndex SplitAnalysis::computeLastSplitPoint(unsigned Num) {
// If CurLI is live into a landing pad successor, move the last split point
// back to the call that may throw.
- if (LPad && LSP.second.isValid() && LIS.isLiveInToMBB(*CurLI, LPad))
- return LSP.second;
- else
+ if (!LPad || !LSP.second || !LIS.isLiveInToMBB(*CurLI, LPad))
+ return LSP.first;
+
+ // Find the value leaving MBB.
+ const VNInfo *VNI = CurLI->getVNInfoBefore(MBBEnd);
+ if (!VNI)
+ return LSP.first;
+
+ // If the value leaving MBB was defined after the call in MBB, it can't
+ // really be live-in to the landing pad. This can happen if the landing pad
+ // has a PHI, and this register is undef on the exceptional edge.
+ // <rdar://problem/10664933>
+ if (!SlotIndex::isEarlierInstr(VNI->def, LSP.second) && VNI->def < MBBEnd)
return LSP.first;
+
+ // Value is properly live-in to the landing pad.
+ // Only allow splits before the call.
+ return LSP.second;
+}
+
+MachineBasicBlock::iterator
+SplitAnalysis::getLastSplitPointIter(MachineBasicBlock *MBB) {
+ SlotIndex LSP = getLastSplitPoint(MBB->getNumber());
+ if (LSP == LIS.getMBBEndIdx(MBB))
+ return MBB->end();
+ return LIS.getInstructionFromIndex(LSP);
}
/// analyzeUses - Count instructions, basic blocks, and loops using CurLI.
@@ -112,7 +135,7 @@ void SplitAnalysis::analyzeUses() {
I = MRI.use_nodbg_begin(CurLI->reg), E = MRI.use_nodbg_end(); I != E;
++I)
if (!I.getOperand().isUndef())
- UseSlots.push_back(LIS.getInstructionIndex(&*I).getDefIndex());
+ UseSlots.push_back(LIS.getInstructionIndex(&*I).getRegSlot());
array_pod_sort(UseSlots.begin(), UseSlots.end());
@@ -328,7 +351,7 @@ void SplitEditor::reset(LiveRangeEdit &LRE, ComplementSpillMode SM) {
// We don't need an AliasAnalysis since we will only be performing
// cheap-as-a-copy remats anyway.
- Edit->anyRematerializable(LIS, TII, 0);
+ Edit->anyRematerializable(0);
}
void SplitEditor::dump() const {
@@ -351,7 +374,7 @@ VNInfo *SplitEditor::defValue(unsigned RegIdx,
LiveInterval *LI = Edit->get(RegIdx);
// Create a new value.
- VNInfo *VNI = LI->getNextValue(Idx, 0, LIS.getVNInfoAllocator());
+ VNInfo *VNI = LI->getNextValue(Idx, LIS.getVNInfoAllocator());
// Use insert for lookup, so we can add missing values with a second lookup.
std::pair<ValueMap::iterator, bool> InsP =
@@ -366,14 +389,14 @@ VNInfo *SplitEditor::defValue(unsigned RegIdx,
// If the previous value was a simple mapping, add liveness for it now.
if (VNInfo *OldVNI = InsP.first->second.getPointer()) {
SlotIndex Def = OldVNI->def;
- LI->addRange(LiveRange(Def, Def.getNextSlot(), OldVNI));
+ LI->addRange(LiveRange(Def, Def.getDeadSlot(), OldVNI));
// No longer a simple mapping. Switch to a complex, non-forced mapping.
InsP.first->second = ValueForcePair();
}
// This is a complex mapping, add liveness for VNI
SlotIndex Def = VNI->def;
- LI->addRange(LiveRange(Def, Def.getNextSlot(), VNI));
+ LI->addRange(LiveRange(Def, Def.getDeadSlot(), VNI));
return VNI;
}
@@ -393,7 +416,7 @@ void SplitEditor::forceRecompute(unsigned RegIdx, const VNInfo *ParentVNI) {
// This was previously a single mapping. Make sure the old def is represented
// by a trivial live range.
SlotIndex Def = VNI->def;
- Edit->get(RegIdx)->addRange(LiveRange(Def, Def.getNextSlot(), VNI));
+ Edit->get(RegIdx)->addRange(LiveRange(Def, Def.getDeadSlot(), VNI));
// Mark as complex mapped, forced.
VFP = ValueForcePair(0, true);
}
@@ -413,33 +436,31 @@ VNInfo *SplitEditor::defFromParent(unsigned RegIdx,
// Attempt cheap-as-a-copy rematerialization.
LiveRangeEdit::Remat RM(ParentVNI);
- if (Edit->canRematerializeAt(RM, UseIdx, true, LIS)) {
- Def = Edit->rematerializeAt(MBB, I, LI->reg, RM, LIS, TII, TRI, Late);
+ if (Edit->canRematerializeAt(RM, UseIdx, true)) {
+ Def = Edit->rematerializeAt(MBB, I, LI->reg, RM, TRI, Late);
++NumRemats;
} else {
// Can't remat, just insert a copy from parent.
CopyMI = BuildMI(MBB, I, DebugLoc(), TII.get(TargetOpcode::COPY), LI->reg)
.addReg(Edit->getReg());
Def = LIS.getSlotIndexes()->insertMachineInstrInMaps(CopyMI, Late)
- .getDefIndex();
+ .getRegSlot();
++NumCopies;
}
// Define the value in Reg.
- VNInfo *VNI = defValue(RegIdx, ParentVNI, Def);
- VNI->setCopy(CopyMI);
- return VNI;
+ return defValue(RegIdx, ParentVNI, Def);
}
/// Create a new virtual register and live interval.
unsigned SplitEditor::openIntv() {
// Create the complement as index 0.
if (Edit->empty())
- Edit->create(LIS, VRM);
+ Edit->create();
// Create the open interval.
OpenIdx = Edit->size();
- Edit->create(LIS, VRM);
+ Edit->create();
return OpenIdx;
}
@@ -497,7 +518,7 @@ SlotIndex SplitEditor::enterIntvAtEnd(MachineBasicBlock &MBB) {
}
DEBUG(dbgs() << ": valno " << ParentVNI->id);
VNInfo *VNI = defFromParent(OpenIdx, ParentVNI, Last, MBB,
- LIS.getLastSplitPoint(Edit->getParent(), &MBB));
+ SA.getLastSplitPointIter(&MBB));
RegAssign.insert(VNI->def, End, OpenIdx);
DEBUG(dump());
return VNI->def;
@@ -586,7 +607,7 @@ SlotIndex SplitEditor::leaveIntvAtTop(MachineBasicBlock &MBB) {
void SplitEditor::overlapIntv(SlotIndex Start, SlotIndex End) {
assert(OpenIdx && "openIntv not called before overlapIntv");
const VNInfo *ParentVNI = Edit->getParent().getVNInfoAt(Start);
- assert(ParentVNI == Edit->getParent().getVNInfoAt(End.getPrevSlot()) &&
+ assert(ParentVNI == Edit->getParent().getVNInfoBefore(End) &&
"Parent changes value in extended range");
assert(LIS.getMBBFromIndex(Start) == LIS.getMBBFromIndex(End) &&
"Range cannot span basic blocks");
@@ -640,7 +661,7 @@ void SplitEditor::removeBackCopies(SmallVectorImpl<VNInfo*> &Copies) {
DEBUG(dbgs() << " cannot find simple kill of RegIdx " << RegIdx << '\n');
forceRecompute(RegIdx, Edit->getParent().getVNInfoAt(Def));
} else {
- SlotIndex Kill = LIS.getInstructionIndex(MBBI).getDefIndex();
+ SlotIndex Kill = LIS.getInstructionIndex(MBBI).getRegSlot();
DEBUG(dbgs() << " move kill to " << Kill << '\t' << *MBBI);
AssignI.setStop(Kill);
}
@@ -780,7 +801,7 @@ void SplitEditor::hoistCopiesForSize() {
SlotIndex Last = LIS.getMBBEndIdx(Dom.first).getPrevSlot();
Dom.second =
defFromParent(0, ParentVNI, Last, *Dom.first,
- LIS.getLastSplitPoint(Edit->getParent(), Dom.first))->def;
+ SA.getLastSplitPointIter(Dom.first))->def;
}
// Remove redundant back-copies that are now known to be dominated by another
@@ -958,7 +979,7 @@ void SplitEditor::rewriteAssigned(bool ExtendRanges) {
// use the same register as the def, so just do that always.
SlotIndex Idx = LIS.getInstructionIndex(MI);
if (MO.isDef() || MO.isUndef())
- Idx = MO.isEarlyClobber() ? Idx.getUseIndex() : Idx.getDefIndex();
+ Idx = Idx.getRegSlot(MO.isEarlyClobber());
// Rewrite to the mapped register at Idx.
unsigned RegIdx = RegAssign.lookup(Idx);
@@ -981,7 +1002,7 @@ void SplitEditor::rewriteAssigned(bool ExtendRanges) {
if (!Edit->getParent().liveAt(Idx))
continue;
} else
- Idx = Idx.getUseIndex();
+ Idx = Idx.getRegSlot(true);
getLRCalc(RegIdx).extend(LI, Idx.getNextSlot(), LIS.getSlotIndexes(),
&MDT, &LIS.getVNInfoAllocator());
@@ -994,8 +1015,8 @@ void SplitEditor::deleteRematVictims() {
LiveInterval *LI = *I;
for (LiveInterval::const_iterator LII = LI->begin(), LIE = LI->end();
LII != LIE; ++LII) {
- // Dead defs end at the store slot.
- if (LII->end != LII->valno->def.getNextSlot())
+ // Dead defs end at the dead slot.
+ if (LII->end != LII->valno->def.getDeadSlot())
continue;
MachineInstr *MI = LIS.getInstructionFromIndex(LII->valno->def);
assert(MI && "Missing instruction for dead def");
@@ -1012,7 +1033,7 @@ void SplitEditor::deleteRematVictims() {
if (Dead.empty())
return;
- Edit->eliminateDeadDefs(Dead, LIS, VRM, TII);
+ Edit->eliminateDeadDefs(Dead);
}
void SplitEditor::finish(SmallVectorImpl<unsigned> *LRMap) {
@@ -1030,7 +1051,6 @@ void SplitEditor::finish(SmallVectorImpl<unsigned> *LRMap) {
unsigned RegIdx = RegAssign.lookup(ParentVNI->def);
VNInfo *VNI = defValue(RegIdx, ParentVNI, ParentVNI->def);
VNI->setIsPHIDef(ParentVNI->isPHIDef());
- VNI->setCopy(ParentVNI->getCopy());
// Force rematted values to be recomputed everywhere.
// The new live ranges may be truncated.
@@ -1049,7 +1069,6 @@ void SplitEditor::finish(SmallVectorImpl<unsigned> *LRMap) {
break;
case SM_Speed:
llvm_unreachable("Spill mode 'speed' not implemented yet");
- break;
}
// Transfer the simply mapped values, check if any are skipped.
@@ -1089,7 +1108,7 @@ void SplitEditor::finish(SmallVectorImpl<unsigned> *LRMap) {
SmallVector<LiveInterval*, 8> dups;
dups.push_back(li);
for (unsigned j = 1; j != NumComp; ++j)
- dups.push_back(&Edit->create(LIS, VRM));
+ dups.push_back(&Edit->create());
ConEQ.Distribute(&dups[0], MRI);
// The new intervals all map back to i.
if (LRMap)
@@ -1097,7 +1116,7 @@ void SplitEditor::finish(SmallVectorImpl<unsigned> *LRMap) {
}
// Calculate spill weight and allocation hints for new intervals.
- Edit->calculateRegClassAndHint(VRM.getMachineFunction(), LIS, SA.Loops);
+ Edit->calculateRegClassAndHint(VRM.getMachineFunction(), SA.Loops);
assert(!LRMap || LRMap->size() == Edit->size());
}
generated by cgit v1.2.3 (git 2.25.1) at 2025-02-21 21:48:55 +0000