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-rw-r--r--contrib/llvm/lib/CodeGen/BranchFolding.cpp264
1 files changed, 168 insertions, 96 deletions
diff --git a/contrib/llvm/lib/CodeGen/BranchFolding.cpp b/contrib/llvm/lib/CodeGen/BranchFolding.cpp
index 7f358a679366..c7a0c6457164 100644
--- a/contrib/llvm/lib/CodeGen/BranchFolding.cpp
+++ b/contrib/llvm/lib/CodeGen/BranchFolding.cpp
@@ -152,7 +152,7 @@ BranchFolder::BranchFolder(bool defaultEnableTailMerge, bool CommonHoist,
void BranchFolder::RemoveDeadBlock(MachineBasicBlock *MBB) {
assert(MBB->pred_empty() && "MBB must be dead!");
- DEBUG(dbgs() << "\nRemoving MBB: " << *MBB);
+ LLVM_DEBUG(dbgs() << "\nRemoving MBB: " << *MBB);
MachineFunction *MF = MBB->getParent();
// drop all successors.
@@ -164,7 +164,7 @@ void BranchFolder::RemoveDeadBlock(MachineBasicBlock *MBB) {
// Remove the block.
MF->erase(MBB);
- FuncletMembership.erase(MBB);
+ EHScopeMembership.erase(MBB);
if (MLI)
MLI->removeBlock(MBB);
}
@@ -199,8 +199,8 @@ bool BranchFolder::OptimizeFunction(MachineFunction &MF,
MadeChange |= MBB.CorrectExtraCFGEdges(TBB, FBB, !Cond.empty());
}
- // Recalculate funclet membership.
- FuncletMembership = getFuncletMembership(MF);
+ // Recalculate EH scope membership.
+ EHScopeMembership = getEHScopeMembership(MF);
bool MadeChangeThisIteration = true;
while (MadeChangeThisIteration) {
@@ -296,6 +296,11 @@ static unsigned HashEndOfMBB(const MachineBasicBlock &MBB) {
return HashMachineInstr(*I);
}
+/// Whether MI should be counted as an instruction when calculating common tail.
+static bool countsAsInstruction(const MachineInstr &MI) {
+ return !(MI.isDebugValue() || MI.isCFIInstruction());
+}
+
/// ComputeCommonTailLength - Given two machine basic blocks, compute the number
/// of instructions they actually have in common together at their end. Return
/// iterators for the first shared instruction in each block.
@@ -310,26 +315,27 @@ static unsigned ComputeCommonTailLength(MachineBasicBlock *MBB1,
while (I1 != MBB1->begin() && I2 != MBB2->begin()) {
--I1; --I2;
// Skip debugging pseudos; necessary to avoid changing the code.
- while (I1->isDebugValue()) {
+ while (!countsAsInstruction(*I1)) {
if (I1==MBB1->begin()) {
- while (I2->isDebugValue()) {
- if (I2==MBB2->begin())
+ while (!countsAsInstruction(*I2)) {
+ if (I2==MBB2->begin()) {
// I1==DBG at begin; I2==DBG at begin
- return TailLen;
+ goto SkipTopCFIAndReturn;
+ }
--I2;
}
++I2;
// I1==DBG at begin; I2==non-DBG, or first of DBGs not at begin
- return TailLen;
+ goto SkipTopCFIAndReturn;
}
--I1;
}
// I1==first (untested) non-DBG preceding known match
- while (I2->isDebugValue()) {
+ while (!countsAsInstruction(*I2)) {
if (I2==MBB2->begin()) {
++I1;
// I1==non-DBG, or first of DBGs not at begin; I2==DBG at begin
- return TailLen;
+ goto SkipTopCFIAndReturn;
}
--I2;
}
@@ -352,7 +358,7 @@ static unsigned ComputeCommonTailLength(MachineBasicBlock *MBB1,
// I1==MBB1->begin() work as expected.)
if (I1 == MBB1->begin() && I2 != MBB2->begin()) {
--I2;
- while (I2->isDebugValue()) {
+ while (I2->isDebugInstr()) {
if (I2 == MBB2->begin())
return TailLen;
--I2;
@@ -361,13 +367,44 @@ static unsigned ComputeCommonTailLength(MachineBasicBlock *MBB1,
}
if (I2 == MBB2->begin() && I1 != MBB1->begin()) {
--I1;
- while (I1->isDebugValue()) {
+ while (I1->isDebugInstr()) {
if (I1 == MBB1->begin())
return TailLen;
--I1;
}
++I1;
}
+
+SkipTopCFIAndReturn:
+ // Ensure that I1 and I2 do not point to a CFI_INSTRUCTION. This can happen if
+ // I1 and I2 are non-identical when compared and then one or both of them ends
+ // up pointing to a CFI instruction after being incremented. For example:
+ /*
+ BB1:
+ ...
+ INSTRUCTION_A
+ ADD32ri8 <- last common instruction
+ ...
+ BB2:
+ ...
+ INSTRUCTION_B
+ CFI_INSTRUCTION
+ ADD32ri8 <- last common instruction
+ ...
+ */
+ // When INSTRUCTION_A and INSTRUCTION_B are compared as not equal, after
+ // incrementing the iterators, I1 will point to ADD, however I2 will point to
+ // the CFI instruction. Later on, this leads to BB2 being 'hacked off' at the
+ // wrong place (in ReplaceTailWithBranchTo()) which results in losing this CFI
+ // instruction.
+ while (I1 != MBB1->end() && I1->isCFIInstruction()) {
+ ++I1;
+ }
+
+ while (I2 != MBB2->end() && I2->isCFIInstruction()) {
+ ++I2;
+ }
+
return TailLen;
}
@@ -438,11 +475,11 @@ MachineBasicBlock *BranchFolder::SplitMBBAt(MachineBasicBlock &CurMBB,
if (UpdateLiveIns)
computeAndAddLiveIns(LiveRegs, *NewMBB);
- // Add the new block to the funclet.
- const auto &FuncletI = FuncletMembership.find(&CurMBB);
- if (FuncletI != FuncletMembership.end()) {
- auto n = FuncletI->second;
- FuncletMembership[NewMBB] = n;
+ // Add the new block to the EH scope.
+ const auto &EHScopeI = EHScopeMembership.find(&CurMBB);
+ if (EHScopeI != EHScopeMembership.end()) {
+ auto n = EHScopeI->second;
+ EHScopeMembership[NewMBB] = n;
}
return NewMBB;
@@ -454,7 +491,7 @@ static unsigned EstimateRuntime(MachineBasicBlock::iterator I,
MachineBasicBlock::iterator E) {
unsigned Time = 0;
for (; I != E; ++I) {
- if (I->isDebugValue())
+ if (!countsAsInstruction(*I))
continue;
if (I->isCall())
Time += 10;
@@ -589,7 +626,7 @@ static bool blockEndsInUnreachable(const MachineBasicBlock *MBB) {
/// SuccBB A common successor of MBB1, MBB2 which are in a canonical form
/// relative to SuccBB
/// PredBB The layout predecessor of SuccBB, if any.
-/// FuncletMembership map from block to funclet #.
+/// EHScopeMembership map from block to EH scope #.
/// AfterPlacement True if we are merging blocks after layout. Stricter
/// thresholds apply to prevent undoing tail-duplication.
static bool
@@ -598,24 +635,24 @@ ProfitableToMerge(MachineBasicBlock *MBB1, MachineBasicBlock *MBB2,
MachineBasicBlock::iterator &I1,
MachineBasicBlock::iterator &I2, MachineBasicBlock *SuccBB,
MachineBasicBlock *PredBB,
- DenseMap<const MachineBasicBlock *, int> &FuncletMembership,
+ DenseMap<const MachineBasicBlock *, int> &EHScopeMembership,
bool AfterPlacement) {
- // It is never profitable to tail-merge blocks from two different funclets.
- if (!FuncletMembership.empty()) {
- auto Funclet1 = FuncletMembership.find(MBB1);
- assert(Funclet1 != FuncletMembership.end());
- auto Funclet2 = FuncletMembership.find(MBB2);
- assert(Funclet2 != FuncletMembership.end());
- if (Funclet1->second != Funclet2->second)
+ // It is never profitable to tail-merge blocks from two different EH scopes.
+ if (!EHScopeMembership.empty()) {
+ auto EHScope1 = EHScopeMembership.find(MBB1);
+ assert(EHScope1 != EHScopeMembership.end());
+ auto EHScope2 = EHScopeMembership.find(MBB2);
+ assert(EHScope2 != EHScopeMembership.end());
+ if (EHScope1->second != EHScope2->second)
return false;
}
CommonTailLen = ComputeCommonTailLength(MBB1, MBB2, I1, I2);
if (CommonTailLen == 0)
return false;
- DEBUG(dbgs() << "Common tail length of " << printMBBReference(*MBB1)
- << " and " << printMBBReference(*MBB2) << " is " << CommonTailLen
- << '\n');
+ LLVM_DEBUG(dbgs() << "Common tail length of " << printMBBReference(*MBB1)
+ << " and " << printMBBReference(*MBB2) << " is "
+ << CommonTailLen << '\n');
// It's almost always profitable to merge any number of non-terminator
// instructions with the block that falls through into the common successor.
@@ -706,7 +743,7 @@ unsigned BranchFolder::ComputeSameTails(unsigned CurHash,
MinCommonTailLength,
CommonTailLen, TrialBBI1, TrialBBI2,
SuccBB, PredBB,
- FuncletMembership,
+ EHScopeMembership,
AfterBlockPlacement)) {
if (CommonTailLen > maxCommonTailLength) {
SameTails.clear();
@@ -770,8 +807,8 @@ bool BranchFolder::CreateCommonTailOnlyBlock(MachineBasicBlock *&PredBB,
SameTails[commonTailIndex].getTailStartPos();
MachineBasicBlock *MBB = SameTails[commonTailIndex].getBlock();
- DEBUG(dbgs() << "\nSplitting " << printMBBReference(*MBB) << ", size "
- << maxCommonTailLength);
+ LLVM_DEBUG(dbgs() << "\nSplitting " << printMBBReference(*MBB) << ", size "
+ << maxCommonTailLength);
// If the split block unconditionally falls-thru to SuccBB, it will be
// merged. In control flow terms it should then take SuccBB's name. e.g. If
@@ -780,7 +817,7 @@ bool BranchFolder::CreateCommonTailOnlyBlock(MachineBasicBlock *&PredBB,
SuccBB->getBasicBlock() : MBB->getBasicBlock();
MachineBasicBlock *newMBB = SplitMBBAt(*MBB, BBI, BB);
if (!newMBB) {
- DEBUG(dbgs() << "... failed!");
+ LLVM_DEBUG(dbgs() << "... failed!");
return false;
}
@@ -814,12 +851,12 @@ mergeOperations(MachineBasicBlock::iterator MBBIStartPos,
assert(MBBI != MBBIE && "Reached BB end within common tail length!");
(void)MBBIE;
- if (MBBI->isDebugValue()) {
+ if (!countsAsInstruction(*MBBI)) {
++MBBI;
continue;
}
- while ((MBBICommon != MBBIECommon) && MBBICommon->isDebugValue())
+ while ((MBBICommon != MBBIECommon) && !countsAsInstruction(*MBBICommon))
++MBBICommon;
assert(MBBICommon != MBBIECommon &&
@@ -859,7 +896,7 @@ void BranchFolder::mergeCommonTails(unsigned commonTailIndex) {
}
for (auto &MI : *MBB) {
- if (MI.isDebugValue())
+ if (!countsAsInstruction(MI))
continue;
DebugLoc DL = MI.getDebugLoc();
for (unsigned int i = 0 ; i < NextCommonInsts.size() ; i++) {
@@ -869,7 +906,7 @@ void BranchFolder::mergeCommonTails(unsigned commonTailIndex) {
auto &Pos = NextCommonInsts[i];
assert(Pos != SameTails[i].getBlock()->end() &&
"Reached BB end within common tail");
- while (Pos->isDebugValue()) {
+ while (!countsAsInstruction(*Pos)) {
++Pos;
assert(Pos != SameTails[i].getBlock()->end() &&
"Reached BB end within common tail");
@@ -884,11 +921,12 @@ void BranchFolder::mergeCommonTails(unsigned commonTailIndex) {
if (UpdateLiveIns) {
LivePhysRegs NewLiveIns(*TRI);
computeLiveIns(NewLiveIns, *MBB);
+ LiveRegs.init(*TRI);
// The flag merging may lead to some register uses no longer using the
// <undef> flag, add IMPLICIT_DEFs in the predecessors as necessary.
for (MachineBasicBlock *Pred : MBB->predecessors()) {
- LiveRegs.init(*TRI);
+ LiveRegs.clear();
LiveRegs.addLiveOuts(*Pred);
MachineBasicBlock::iterator InsertBefore = Pred->getFirstTerminator();
for (unsigned Reg : NewLiveIns) {
@@ -919,18 +957,19 @@ bool BranchFolder::TryTailMergeBlocks(MachineBasicBlock *SuccBB,
unsigned MinCommonTailLength) {
bool MadeChange = false;
- DEBUG(dbgs() << "\nTryTailMergeBlocks: ";
- for (unsigned i = 0, e = MergePotentials.size(); i != e; ++i) dbgs()
- << printMBBReference(*MergePotentials[i].getBlock())
- << (i == e - 1 ? "" : ", ");
- dbgs() << "\n"; if (SuccBB) {
- dbgs() << " with successor " << printMBBReference(*SuccBB) << '\n';
- if (PredBB)
- dbgs() << " which has fall-through from "
- << printMBBReference(*PredBB) << "\n";
- } dbgs() << "Looking for common tails of at least "
- << MinCommonTailLength << " instruction"
- << (MinCommonTailLength == 1 ? "" : "s") << '\n';);
+ LLVM_DEBUG(
+ dbgs() << "\nTryTailMergeBlocks: ";
+ for (unsigned i = 0, e = MergePotentials.size(); i != e; ++i) dbgs()
+ << printMBBReference(*MergePotentials[i].getBlock())
+ << (i == e - 1 ? "" : ", ");
+ dbgs() << "\n"; if (SuccBB) {
+ dbgs() << " with successor " << printMBBReference(*SuccBB) << '\n';
+ if (PredBB)
+ dbgs() << " which has fall-through from "
+ << printMBBReference(*PredBB) << "\n";
+ } dbgs() << "Looking for common tails of at least "
+ << MinCommonTailLength << " instruction"
+ << (MinCommonTailLength == 1 ? "" : "s") << '\n';);
// Sort by hash value so that blocks with identical end sequences sort
// together.
@@ -1010,19 +1049,19 @@ bool BranchFolder::TryTailMergeBlocks(MachineBasicBlock *SuccBB,
// MBB is common tail. Adjust all other BB's to jump to this one.
// Traversal must be forwards so erases work.
- DEBUG(dbgs() << "\nUsing common tail in " << printMBBReference(*MBB)
- << " for ");
+ LLVM_DEBUG(dbgs() << "\nUsing common tail in " << printMBBReference(*MBB)
+ << " for ");
for (unsigned int i=0, e = SameTails.size(); i != e; ++i) {
if (commonTailIndex == i)
continue;
- DEBUG(dbgs() << printMBBReference(*SameTails[i].getBlock())
- << (i == e - 1 ? "" : ", "));
+ LLVM_DEBUG(dbgs() << printMBBReference(*SameTails[i].getBlock())
+ << (i == e - 1 ? "" : ", "));
// Hack the end off BB i, making it jump to BB commonTailIndex instead.
replaceTailWithBranchTo(SameTails[i].getTailStartPos(), *MBB);
// BB i is no longer a predecessor of SuccBB; remove it from the worklist.
MergePotentials.erase(SameTails[i].getMPIter());
}
- DEBUG(dbgs() << "\n");
+ LLVM_DEBUG(dbgs() << "\n");
// We leave commonTailIndex in the worklist in case there are other blocks
// that match it with a smaller number of instructions.
MadeChange = true;
@@ -1254,8 +1293,8 @@ bool BranchFolder::OptimizeBranches(MachineFunction &MF) {
// Make sure blocks are numbered in order
MF.RenumberBlocks();
- // Renumbering blocks alters funclet membership, recalculate it.
- FuncletMembership = getFuncletMembership(MF);
+ // Renumbering blocks alters EH scope membership, recalculate it.
+ EHScopeMembership = getEHScopeMembership(MF);
for (MachineFunction::iterator I = std::next(MF.begin()), E = MF.end();
I != E; ) {
@@ -1319,6 +1358,53 @@ static DebugLoc getBranchDebugLoc(MachineBasicBlock &MBB) {
return DebugLoc();
}
+static void copyDebugInfoToPredecessor(const TargetInstrInfo *TII,
+ MachineBasicBlock &MBB,
+ MachineBasicBlock &PredMBB) {
+ auto InsertBefore = PredMBB.getFirstTerminator();
+ for (MachineInstr &MI : MBB.instrs())
+ if (MI.isDebugValue()) {
+ TII->duplicate(PredMBB, InsertBefore, MI);
+ LLVM_DEBUG(dbgs() << "Copied debug value from empty block to pred: "
+ << MI);
+ }
+}
+
+static void copyDebugInfoToSuccessor(const TargetInstrInfo *TII,
+ MachineBasicBlock &MBB,
+ MachineBasicBlock &SuccMBB) {
+ auto InsertBefore = SuccMBB.SkipPHIsAndLabels(SuccMBB.begin());
+ for (MachineInstr &MI : MBB.instrs())
+ if (MI.isDebugValue()) {
+ TII->duplicate(SuccMBB, InsertBefore, MI);
+ LLVM_DEBUG(dbgs() << "Copied debug value from empty block to succ: "
+ << MI);
+ }
+}
+
+// Try to salvage DBG_VALUE instructions from an otherwise empty block. If such
+// a basic block is removed we would lose the debug information unless we have
+// copied the information to a predecessor/successor.
+//
+// TODO: This function only handles some simple cases. An alternative would be
+// to run a heavier analysis, such as the LiveDebugValues pass, before we do
+// branch folding.
+static void salvageDebugInfoFromEmptyBlock(const TargetInstrInfo *TII,
+ MachineBasicBlock &MBB) {
+ assert(IsEmptyBlock(&MBB) && "Expected an empty block (except debug info).");
+ // If this MBB is the only predecessor of a successor it is legal to copy
+ // DBG_VALUE instructions to the beginning of the successor.
+ for (MachineBasicBlock *SuccBB : MBB.successors())
+ if (SuccBB->pred_size() == 1)
+ copyDebugInfoToSuccessor(TII, MBB, *SuccBB);
+ // If this MBB is the only successor of a predecessor it is legal to copy the
+ // DBG_VALUE instructions to the end of the predecessor (just before the
+ // terminators, assuming that the terminator isn't affecting the DBG_VALUE).
+ for (MachineBasicBlock *PredBB : MBB.predecessors())
+ if (PredBB->succ_size() == 1)
+ copyDebugInfoToPredecessor(TII, MBB, *PredBB);
+}
+
bool BranchFolder::OptimizeBlock(MachineBasicBlock *MBB) {
bool MadeChange = false;
MachineFunction &MF = *MBB->getParent();
@@ -1327,14 +1413,14 @@ ReoptimizeBlock:
MachineFunction::iterator FallThrough = MBB->getIterator();
++FallThrough;
- // Make sure MBB and FallThrough belong to the same funclet.
- bool SameFunclet = true;
- if (!FuncletMembership.empty() && FallThrough != MF.end()) {
- auto MBBFunclet = FuncletMembership.find(MBB);
- assert(MBBFunclet != FuncletMembership.end());
- auto FallThroughFunclet = FuncletMembership.find(&*FallThrough);
- assert(FallThroughFunclet != FuncletMembership.end());
- SameFunclet = MBBFunclet->second == FallThroughFunclet->second;
+ // Make sure MBB and FallThrough belong to the same EH scope.
+ bool SameEHScope = true;
+ if (!EHScopeMembership.empty() && FallThrough != MF.end()) {
+ auto MBBEHScope = EHScopeMembership.find(MBB);
+ assert(MBBEHScope != EHScopeMembership.end());
+ auto FallThroughEHScope = EHScopeMembership.find(&*FallThrough);
+ assert(FallThroughEHScope != EHScopeMembership.end());
+ SameEHScope = MBBEHScope->second == FallThroughEHScope->second;
}
// If this block is empty, make everyone use its fall-through, not the block
@@ -1342,7 +1428,8 @@ ReoptimizeBlock:
// points to this block. Blocks with their addresses taken shouldn't be
// optimized away.
if (IsEmptyBlock(MBB) && !MBB->isEHPad() && !MBB->hasAddressTaken() &&
- SameFunclet) {
+ SameEHScope) {
+ salvageDebugInfoFromEmptyBlock(TII, *MBB);
// Dead block? Leave for cleanup later.
if (MBB->pred_empty()) return MadeChange;
@@ -1406,8 +1493,8 @@ ReoptimizeBlock:
if (PriorCond.empty() && !PriorTBB && MBB->pred_size() == 1 &&
PrevBB.succ_size() == 1 &&
!MBB->hasAddressTaken() && !MBB->isEHPad()) {
- DEBUG(dbgs() << "\nMerging into block: " << PrevBB
- << "From MBB: " << *MBB);
+ LLVM_DEBUG(dbgs() << "\nMerging into block: " << PrevBB
+ << "From MBB: " << *MBB);
// Remove redundant DBG_VALUEs first.
if (PrevBB.begin() != PrevBB.end()) {
MachineBasicBlock::iterator PrevBBIter = PrevBB.end();
@@ -1416,7 +1503,7 @@ ReoptimizeBlock:
// Check if DBG_VALUE at the end of PrevBB is identical to the
// DBG_VALUE at the beginning of MBB.
while (PrevBBIter != PrevBB.begin() && MBBIter != MBB->end()
- && PrevBBIter->isDebugValue() && MBBIter->isDebugValue()) {
+ && PrevBBIter->isDebugInstr() && MBBIter->isDebugInstr()) {
if (!MBBIter->isIdenticalTo(*PrevBBIter))
break;
MachineInstr &DuplicateDbg = *MBBIter;
@@ -1493,8 +1580,8 @@ ReoptimizeBlock:
// Reverse the branch so we will fall through on the previous true cond.
SmallVector<MachineOperand, 4> NewPriorCond(PriorCond);
if (!TII->reverseBranchCondition(NewPriorCond)) {
- DEBUG(dbgs() << "\nMoving MBB: " << *MBB
- << "To make fallthrough to: " << *PriorTBB << "\n");
+ LLVM_DEBUG(dbgs() << "\nMoving MBB: " << *MBB
+ << "To make fallthrough to: " << *PriorTBB << "\n");
DebugLoc dl = getBranchDebugLoc(PrevBB);
TII->removeBranch(PrevBB);
@@ -1829,8 +1916,12 @@ MachineBasicBlock::iterator findHoistingInsertPosAndDeps(MachineBasicBlock *MBB,
if (Uses.empty())
return Loc;
+ // If the terminator is the only instruction in the block and Uses is not
+ // empty (or we would have returned above), we can still safely hoist
+ // instructions just before the terminator as long as the Defs/Uses are not
+ // violated (which is checked in HoistCommonCodeInSuccs).
if (Loc == MBB->begin())
- return MBB->end();
+ return Loc;
// The terminator is probably a conditional branch, try not to separate the
// branch from condition setting instruction.
@@ -1917,7 +2008,6 @@ bool BranchFolder::HoistCommonCodeInSuccs(MachineBasicBlock *MBB) {
return false;
bool HasDups = false;
- SmallVector<unsigned, 4> LocalDefs, LocalKills;
SmallSet<unsigned, 4> ActiveDefsSet, AllDefsSet;
MachineBasicBlock::iterator TIB = TBB->begin();
MachineBasicBlock::iterator FIB = FBB->begin();
@@ -2000,7 +2090,6 @@ bool BranchFolder::HoistCommonCodeInSuccs(MachineBasicBlock *MBB) {
if (!Reg)
continue;
if (!AllDefsSet.count(Reg)) {
- LocalKills.push_back(Reg);
continue;
}
if (TargetRegisterInfo::isPhysicalRegister(Reg)) {
@@ -2018,7 +2107,6 @@ bool BranchFolder::HoistCommonCodeInSuccs(MachineBasicBlock *MBB) {
unsigned Reg = MO.getReg();
if (!Reg || TargetRegisterInfo::isVirtualRegister(Reg))
continue;
- LocalDefs.push_back(Reg);
addRegAndItsAliases(Reg, TRI, ActiveDefsSet);
addRegAndItsAliases(Reg, TRI, AllDefsSet);
}
@@ -2034,25 +2122,9 @@ bool BranchFolder::HoistCommonCodeInSuccs(MachineBasicBlock *MBB) {
MBB->splice(Loc, TBB, TBB->begin(), TIB);
FBB->erase(FBB->begin(), FIB);
- // Update livein's.
- bool ChangedLiveIns = false;
- for (unsigned i = 0, e = LocalDefs.size(); i != e; ++i) {
- unsigned Def = LocalDefs[i];
- if (ActiveDefsSet.count(Def)) {
- TBB->addLiveIn(Def);
- FBB->addLiveIn(Def);
- ChangedLiveIns = true;
- }
- }
- for (unsigned K : LocalKills) {
- TBB->removeLiveIn(K);
- FBB->removeLiveIn(K);
- ChangedLiveIns = true;
- }
-
- if (ChangedLiveIns) {
- TBB->sortUniqueLiveIns();
- FBB->sortUniqueLiveIns();
+ if (UpdateLiveIns) {
+ recomputeLiveIns(*TBB);
+ recomputeLiveIns(*FBB);
}
++NumHoist;
generated by cgit v1.2.3 (git 2.25.1) at 2025-07-30 17:13:37 +0000