Reverting [JumpThreading] Preservation of DT and LVI across the pass
Stage 2 bootstrap failed:
http://lab.llvm.org:8011/builders/clang-x86_64-linux-selfhost-modules-2/builds/14434
llvm-svn: 320641
diff --git a/llvm/lib/Transforms/Scalar/CorrelatedValuePropagation.cpp b/llvm/lib/Transforms/Scalar/CorrelatedValuePropagation.cpp
index 535d43c..8f468eb 100644
--- a/llvm/lib/Transforms/Scalar/CorrelatedValuePropagation.cpp
+++ b/llvm/lib/Transforms/Scalar/CorrelatedValuePropagation.cpp
@@ -77,7 +77,6 @@
bool runOnFunction(Function &F) override;
void getAnalysisUsage(AnalysisUsage &AU) const override {
- AU.addRequired<DominatorTreeWrapperPass>();
AU.addRequired<LazyValueInfoWrapperPass>();
AU.addPreserved<GlobalsAAWrapperPass>();
}
@@ -89,7 +88,6 @@
INITIALIZE_PASS_BEGIN(CorrelatedValuePropagation, "correlated-propagation",
"Value Propagation", false, false)
-INITIALIZE_PASS_DEPENDENCY(DominatorTreeWrapperPass)
INITIALIZE_PASS_DEPENDENCY(LazyValueInfoWrapperPass)
INITIALIZE_PASS_END(CorrelatedValuePropagation, "correlated-propagation",
"Value Propagation", false, false)
diff --git a/llvm/lib/Transforms/Scalar/JumpThreading.cpp b/llvm/lib/Transforms/Scalar/JumpThreading.cpp
index 95dd9d1..6b0377e 100644
--- a/llvm/lib/Transforms/Scalar/JumpThreading.cpp
+++ b/llvm/lib/Transforms/Scalar/JumpThreading.cpp
@@ -37,7 +37,6 @@
#include "llvm/IR/ConstantRange.h"
#include "llvm/IR/Constants.h"
#include "llvm/IR/DataLayout.h"
-#include "llvm/IR/DeferredDominance.h"
#include "llvm/IR/Dominators.h"
#include "llvm/IR/Function.h"
#include "llvm/IR/InstrTypes.h"
@@ -132,11 +131,10 @@
bool runOnFunction(Function &F) override;
void getAnalysisUsage(AnalysisUsage &AU) const override {
- AU.addRequired<DominatorTreeWrapperPass>();
- AU.addPreserved<DominatorTreeWrapperPass>();
+ if (PrintLVIAfterJumpThreading)
+ AU.addRequired<DominatorTreeWrapperPass>();
AU.addRequired<AAResultsWrapperPass>();
AU.addRequired<LazyValueInfoWrapperPass>();
- AU.addPreserved<LazyValueInfoWrapperPass>();
AU.addPreserved<GlobalsAAWrapperPass>();
AU.addRequired<TargetLibraryInfoWrapperPass>();
}
@@ -150,7 +148,6 @@
INITIALIZE_PASS_BEGIN(JumpThreading, "jump-threading",
"Jump Threading", false, false)
-INITIALIZE_PASS_DEPENDENCY(DominatorTreeWrapperPass)
INITIALIZE_PASS_DEPENDENCY(LazyValueInfoWrapperPass)
INITIALIZE_PASS_DEPENDENCY(TargetLibraryInfoWrapperPass)
INITIALIZE_PASS_DEPENDENCY(AAResultsWrapperPass)
@@ -281,12 +278,8 @@
if (skipFunction(F))
return false;
auto TLI = &getAnalysis<TargetLibraryInfoWrapperPass>().getTLI();
- // Get DT analysis before LVI. When LVI is initialized it conditionally adds
- // DT if it's available.
- auto DT = &getAnalysis<DominatorTreeWrapperPass>().getDomTree();
auto LVI = &getAnalysis<LazyValueInfoWrapperPass>().getLVI();
auto AA = &getAnalysis<AAResultsWrapperPass>().getAAResults();
- DeferredDominance DDT(*DT);
std::unique_ptr<BlockFrequencyInfo> BFI;
std::unique_ptr<BranchProbabilityInfo> BPI;
bool HasProfileData = F.getEntryCount().hasValue();
@@ -296,11 +289,12 @@
BFI.reset(new BlockFrequencyInfo(F, *BPI, LI));
}
- bool Changed = Impl.runImpl(F, TLI, LVI, AA, &DDT, HasProfileData,
- std::move(BFI), std::move(BPI));
+ bool Changed = Impl.runImpl(F, TLI, LVI, AA, HasProfileData, std::move(BFI),
+ std::move(BPI));
if (PrintLVIAfterJumpThreading) {
dbgs() << "LVI for function '" << F.getName() << "':\n";
- LVI->printLVI(F, *DT, dbgs());
+ LVI->printLVI(F, getAnalysis<DominatorTreeWrapperPass>().getDomTree(),
+ dbgs());
}
return Changed;
}
@@ -308,12 +302,8 @@
PreservedAnalyses JumpThreadingPass::run(Function &F,
FunctionAnalysisManager &AM) {
auto &TLI = AM.getResult<TargetLibraryAnalysis>(F);
- // Get DT analysis before LVI. When LVI is initialized it conditionally adds
- // DT if it's available.
- auto &DT = AM.getResult<DominatorTreeAnalysis>(F);
auto &LVI = AM.getResult<LazyValueAnalysis>(F);
auto &AA = AM.getResult<AAManager>(F);
- DeferredDominance DDT(DT);
std::unique_ptr<BlockFrequencyInfo> BFI;
std::unique_ptr<BranchProbabilityInfo> BPI;
@@ -324,28 +314,25 @@
BFI.reset(new BlockFrequencyInfo(F, *BPI, LI));
}
- bool Changed = runImpl(F, &TLI, &LVI, &AA, &DDT, HasProfileData,
- std::move(BFI), std::move(BPI));
+ bool Changed = runImpl(F, &TLI, &LVI, &AA, HasProfileData, std::move(BFI),
+ std::move(BPI));
if (!Changed)
return PreservedAnalyses::all();
PreservedAnalyses PA;
PA.preserve<GlobalsAA>();
- PA.preserve<DominatorTreeAnalysis>();
- PA.preserve<LazyValueAnalysis>();
return PA;
}
bool JumpThreadingPass::runImpl(Function &F, TargetLibraryInfo *TLI_,
LazyValueInfo *LVI_, AliasAnalysis *AA_,
- DeferredDominance *DDT_, bool HasProfileData_,
+ bool HasProfileData_,
std::unique_ptr<BlockFrequencyInfo> BFI_,
std::unique_ptr<BranchProbabilityInfo> BPI_) {
DEBUG(dbgs() << "Jump threading on function '" << F.getName() << "'\n");
TLI = TLI_;
LVI = LVI_;
AA = AA_;
- DDT = DDT_;
BFI.reset();
BPI.reset();
// When profile data is available, we need to update edge weights after
@@ -367,7 +354,7 @@
// back edges. This works for normal cases but not for unreachable blocks as
// they may have cycle with no back edge.
bool EverChanged = false;
- EverChanged |= removeUnreachableBlocks(F, LVI, DDT);
+ EverChanged |= removeUnreachableBlocks(F, LVI);
FindLoopHeaders(F);
@@ -382,10 +369,6 @@
++I;
- // Don't thread branches over a block that's slated for deletion.
- if (DDT->pendingDeletedBB(BB))
- continue;
-
// If the block is trivially dead, zap it. This eliminates the successor
// edges which simplifies the CFG.
if (pred_empty(BB) &&
@@ -394,7 +377,7 @@
<< "' with terminator: " << *BB->getTerminator() << '\n');
LoopHeaders.erase(BB);
LVI->eraseBlock(BB);
- DeleteDeadBlock(BB, DDT);
+ DeleteDeadBlock(BB);
Changed = true;
continue;
}
@@ -418,7 +401,7 @@
// awesome, but it allows us to use AssertingVH to prevent nasty
// dangling pointer issues within LazyValueInfo.
LVI->eraseBlock(BB);
- if (TryToSimplifyUncondBranchFromEmptyBlock(BB, DDT))
+ if (TryToSimplifyUncondBranchFromEmptyBlock(BB))
Changed = true;
}
}
@@ -426,7 +409,6 @@
} while (Changed);
LoopHeaders.clear();
- DDT->flush();
return EverChanged;
}
@@ -950,8 +932,8 @@
bool JumpThreadingPass::ProcessBlock(BasicBlock *BB) {
// If the block is trivially dead, just return and let the caller nuke it.
// This simplifies other transformations.
- if (DDT->pendingDeletedBB(BB) ||
- (pred_empty(BB) && BB != &BB->getParent()->getEntryBlock()))
+ if (pred_empty(BB) &&
+ BB != &BB->getParent()->getEntryBlock())
return false;
// If this block has a single predecessor, and if that pred has a single
@@ -967,7 +949,7 @@
LoopHeaders.insert(BB);
LVI->eraseBlock(SinglePred);
- MergeBasicBlockIntoOnlyPred(BB, nullptr, DDT);
+ MergeBasicBlockIntoOnlyPred(BB);
// Now that BB is merged into SinglePred (i.e. SinglePred Code followed by
// BB code within one basic block `BB`), we need to invalidate the LVI
@@ -1050,23 +1032,18 @@
// successors to branch to. Let GetBestDestForJumpOnUndef decide.
if (isa<UndefValue>(Condition)) {
unsigned BestSucc = GetBestDestForJumpOnUndef(BB);
- std::vector<DominatorTree::UpdateType> Updates;
// Fold the branch/switch.
TerminatorInst *BBTerm = BB->getTerminator();
- Updates.reserve(BBTerm->getNumSuccessors());
for (unsigned i = 0, e = BBTerm->getNumSuccessors(); i != e; ++i) {
if (i == BestSucc) continue;
- BasicBlock *Succ = BBTerm->getSuccessor(i);
- Succ->removePredecessor(BB, true);
- Updates.push_back({DominatorTree::Delete, BB, Succ});
+ BBTerm->getSuccessor(i)->removePredecessor(BB, true);
}
DEBUG(dbgs() << " In block '" << BB->getName()
<< "' folding undef terminator: " << *BBTerm << '\n');
BranchInst::Create(BBTerm->getSuccessor(BestSucc), BBTerm);
BBTerm->eraseFromParent();
- DDT->applyUpdates(Updates);
return true;
}
@@ -1077,7 +1054,7 @@
DEBUG(dbgs() << " In block '" << BB->getName()
<< "' folding terminator: " << *BB->getTerminator() << '\n');
++NumFolds;
- ConstantFoldTerminator(BB, true, nullptr, DDT);
+ ConstantFoldTerminator(BB, true);
return true;
}
@@ -1110,8 +1087,7 @@
if (Ret != LazyValueInfo::Unknown) {
unsigned ToRemove = Ret == LazyValueInfo::True ? 1 : 0;
unsigned ToKeep = Ret == LazyValueInfo::True ? 0 : 1;
- BasicBlock *ToRemoveSucc = CondBr->getSuccessor(ToRemove);
- ToRemoveSucc->removePredecessor(BB, true);
+ CondBr->getSuccessor(ToRemove)->removePredecessor(BB, true);
BranchInst::Create(CondBr->getSuccessor(ToKeep), CondBr);
CondBr->eraseFromParent();
if (CondCmp->use_empty())
@@ -1129,7 +1105,6 @@
ConstantInt::getFalse(CondCmp->getType());
ReplaceFoldableUses(CondCmp, CI);
}
- DDT->deleteEdge(BB, ToRemoveSucc);
return true;
}
@@ -1208,12 +1183,9 @@
Optional<bool> Implication =
isImpliedCondition(PBI->getCondition(), Cond, DL, CondIsTrue);
if (Implication) {
- BasicBlock *KeepSucc = BI->getSuccessor(*Implication ? 0 : 1);
- BasicBlock *RemoveSucc = BI->getSuccessor(*Implication ? 1 : 0);
- RemoveSucc->removePredecessor(BB);
- BranchInst::Create(KeepSucc, BI);
+ BI->getSuccessor(*Implication ? 1 : 0)->removePredecessor(BB);
+ BranchInst::Create(BI->getSuccessor(*Implication ? 0 : 1), BI);
BI->eraseFromParent();
- DDT->deleteEdge(BB, RemoveSucc);
return true;
}
CurrentBB = CurrentPred;
@@ -1606,22 +1578,17 @@
if (PredWithKnownDest ==
(size_t)std::distance(pred_begin(BB), pred_end(BB))) {
bool SeenFirstBranchToOnlyDest = false;
- std::vector <DominatorTree::UpdateType> Updates;
- Updates.reserve(BB->getTerminator()->getNumSuccessors() - 1);
for (BasicBlock *SuccBB : successors(BB)) {
- if (SuccBB == OnlyDest && !SeenFirstBranchToOnlyDest) {
+ if (SuccBB == OnlyDest && !SeenFirstBranchToOnlyDest)
SeenFirstBranchToOnlyDest = true; // Don't modify the first branch.
- } else {
+ else
SuccBB->removePredecessor(BB, true); // This is unreachable successor.
- Updates.push_back({DominatorTree::Delete, BB, SuccBB});
- }
}
// Finally update the terminator.
TerminatorInst *Term = BB->getTerminator();
BranchInst::Create(OnlyDest, Term);
Term->eraseFromParent();
- DDT->applyUpdates(Updates);
// If the condition is now dead due to the removal of the old terminator,
// erase it.
@@ -1985,10 +1952,6 @@
PredTerm->setSuccessor(i, NewBB);
}
- DDT->applyUpdates({{DominatorTree::Insert, NewBB, SuccBB},
- {DominatorTree::Insert, PredBB, NewBB},
- {DominatorTree::Delete, PredBB, BB}});
-
// At this point, the IR is fully up to date and consistent. Do a quick scan
// over the new instructions and zap any that are constants or dead. This
// frequently happens because of phi translation.
@@ -2008,42 +1971,20 @@
BasicBlock *JumpThreadingPass::SplitBlockPreds(BasicBlock *BB,
ArrayRef<BasicBlock *> Preds,
const char *Suffix) {
- SmallVector<BasicBlock *, 2> NewBBs;
-
// Collect the frequencies of all predecessors of BB, which will be used to
- // update the edge weight of the result of splitting predecessors.
- DenseMap<BasicBlock *, BlockFrequency> FreqMap;
+ // update the edge weight on BB->SuccBB.
+ BlockFrequency PredBBFreq(0);
if (HasProfileData)
for (auto Pred : Preds)
- FreqMap.insert(std::make_pair(
- Pred, BFI->getBlockFreq(Pred) * BPI->getEdgeProbability(Pred, BB)));
+ PredBBFreq += BFI->getBlockFreq(Pred) * BPI->getEdgeProbability(Pred, BB);
- // In the case when BB is a LandingPad block we create 2 new predecessors
- // instead of just one.
- if (BB->isLandingPad()) {
- std::string NewName = std::string(Suffix) + ".split-lp";
- SplitLandingPadPredecessors(BB, Preds, Suffix, NewName.c_str(), NewBBs);
- } else {
- NewBBs.push_back(SplitBlockPredecessors(BB, Preds, Suffix));
- }
+ BasicBlock *PredBB = SplitBlockPredecessors(BB, Preds, Suffix);
- std::vector<DominatorTree::UpdateType> Updates;
- Updates.reserve((2 * Preds.size()) + NewBBs.size());
- for (auto NewBB : NewBBs) {
- BlockFrequency NewBBFreq(0);
- Updates.push_back({DominatorTree::Insert, NewBB, BB});
- for (auto Pred : predecessors(NewBB)) {
- Updates.push_back({DominatorTree::Delete, Pred, BB});
- Updates.push_back({DominatorTree::Insert, Pred, NewBB});
- if (HasProfileData) // Update frequencies between Pred -> NewBB.
- NewBBFreq += FreqMap.lookup(Pred);
- }
- if (HasProfileData) // Apply the summed frequency to NewBB.
- BFI->setBlockFreq(NewBB, NewBBFreq.getFrequency());
- }
-
- DDT->applyUpdates(Updates);
- return NewBBs[0];
+ // Set the block frequency of the newly created PredBB, which is the sum of
+ // frequencies of Preds.
+ if (HasProfileData)
+ BFI->setBlockFreq(PredBB, PredBBFreq.getFrequency());
+ return PredBB;
}
bool JumpThreadingPass::doesBlockHaveProfileData(BasicBlock *BB) {
@@ -2187,7 +2128,6 @@
}
// And finally, do it! Start by factoring the predecessors if needed.
- std::vector<DominatorTree::UpdateType> Updates;
BasicBlock *PredBB;
if (PredBBs.size() == 1)
PredBB = PredBBs[0];
@@ -2196,7 +2136,6 @@
<< " common predecessors.\n");
PredBB = SplitBlockPreds(BB, PredBBs, ".thr_comm");
}
- Updates.push_back({DominatorTree::Delete, PredBB, BB});
// Okay, we decided to do this! Clone all the instructions in BB onto the end
// of PredBB.
@@ -2209,11 +2148,7 @@
BranchInst *OldPredBranch = dyn_cast<BranchInst>(PredBB->getTerminator());
if (!OldPredBranch || !OldPredBranch->isUnconditional()) {
- BasicBlock *OldPredBB = PredBB;
- PredBB = SplitEdge(OldPredBB, BB);
- Updates.push_back({DominatorTree::Insert, OldPredBB, PredBB});
- Updates.push_back({DominatorTree::Insert, PredBB, BB});
- Updates.push_back({DominatorTree::Delete, OldPredBB, BB});
+ PredBB = SplitEdge(PredBB, BB);
OldPredBranch = cast<BranchInst>(PredBB->getTerminator());
}
@@ -2255,10 +2190,6 @@
// Otherwise, insert the new instruction into the block.
New->setName(BI->getName());
PredBB->getInstList().insert(OldPredBranch->getIterator(), New);
- // Update Dominance from simplified New instruction operands.
- for (unsigned i = 0, e = New->getNumOperands(); i != e; ++i)
- if (BasicBlock *SuccBB = dyn_cast<BasicBlock>(New->getOperand(i)))
- Updates.push_back({DominatorTree::Insert, PredBB, SuccBB});
}
}
@@ -2314,7 +2245,6 @@
// Remove the unconditional branch at the end of the PredBB block.
OldPredBranch->eraseFromParent();
- DDT->applyUpdates(Updates);
++NumDupes;
return true;
@@ -2387,8 +2317,6 @@
// The select is now dead.
SI->eraseFromParent();
- DDT->applyUpdates({{DominatorTree::Insert, NewBB, BB},
- {DominatorTree::Insert, Pred, NewBB}});
// Update any other PHI nodes in BB.
for (BasicBlock::iterator BI = BB->begin();
PHINode *Phi = dyn_cast<PHINode>(BI); ++BI)
@@ -2467,25 +2395,11 @@
// Expand the select.
TerminatorInst *Term =
SplitBlockAndInsertIfThen(SI->getCondition(), SI, false);
- BasicBlock *SplitBB = SI->getParent();
- BasicBlock *NewBB = Term->getParent();
PHINode *NewPN = PHINode::Create(SI->getType(), 2, "", SI);
NewPN->addIncoming(SI->getTrueValue(), Term->getParent());
NewPN->addIncoming(SI->getFalseValue(), BB);
SI->replaceAllUsesWith(NewPN);
SI->eraseFromParent();
- // NewBB and SplitBB are newly created blocks which require insertion.
- std::vector<DominatorTree::UpdateType> Updates;
- Updates.reserve((2 * SplitBB->getTerminator()->getNumSuccessors()) + 3);
- Updates.push_back({DominatorTree::Insert, BB, SplitBB});
- Updates.push_back({DominatorTree::Insert, BB, NewBB});
- Updates.push_back({DominatorTree::Insert, NewBB, SplitBB});
- // BB's successors were moved to SplitBB, update DDT accordingly.
- for (auto *Succ : successors(SplitBB)) {
- Updates.push_back({DominatorTree::Delete, BB, Succ});
- Updates.push_back({DominatorTree::Insert, SplitBB, Succ});
- }
- DDT->applyUpdates(Updates);
return true;
}
return false;
@@ -2572,8 +2486,8 @@
if (!TrueDestIsSafe && !FalseDestIsSafe)
return false;
- BasicBlock *PredUnguardedBlock = TrueDestIsSafe ? TrueDest : FalseDest;
- BasicBlock *PredGuardedBlock = FalseDestIsSafe ? TrueDest : FalseDest;
+ BasicBlock *UnguardedBlock = TrueDestIsSafe ? TrueDest : FalseDest;
+ BasicBlock *GuardedBlock = FalseDestIsSafe ? TrueDest : FalseDest;
ValueToValueMapTy UnguardedMapping, GuardedMapping;
Instruction *AfterGuard = Guard->getNextNode();
@@ -2582,29 +2496,18 @@
return false;
// Duplicate all instructions before the guard and the guard itself to the
// branch where implication is not proved.
- BasicBlock *GuardedBlock = DuplicateInstructionsInSplitBetween(
- BB, PredGuardedBlock, AfterGuard, GuardedMapping);
+ GuardedBlock = DuplicateInstructionsInSplitBetween(
+ BB, GuardedBlock, AfterGuard, GuardedMapping);
assert(GuardedBlock && "Could not create the guarded block?");
// Duplicate all instructions before the guard in the unguarded branch.
// Since we have successfully duplicated the guarded block and this block
// has fewer instructions, we expect it to succeed.
- BasicBlock *UnguardedBlock = DuplicateInstructionsInSplitBetween(
- BB, PredUnguardedBlock, Guard, UnguardedMapping);
+ UnguardedBlock = DuplicateInstructionsInSplitBetween(BB, UnguardedBlock,
+ Guard, UnguardedMapping);
assert(UnguardedBlock && "Could not create the unguarded block?");
DEBUG(dbgs() << "Moved guard " << *Guard << " to block "
<< GuardedBlock->getName() << "\n");
- // DuplicateInstructionsInSplitBetween inserts a new block "BB.split" between
- // PredBB and BB. We need to perform two inserts and one delete for each of
- // the above calls to update Dominators.
- DDT->applyUpdates(
- {// Guarded block split.
- {DominatorTree::Delete, PredGuardedBlock, BB},
- {DominatorTree::Insert, PredGuardedBlock, GuardedBlock},
- {DominatorTree::Insert, GuardedBlock, BB},
- // Unguarded block split.
- {DominatorTree::Delete, PredUnguardedBlock, BB},
- {DominatorTree::Insert, PredUnguardedBlock, UnguardedBlock},
- {DominatorTree::Insert, UnguardedBlock, BB}});
+
// Some instructions before the guard may still have uses. For them, we need
// to create Phi nodes merging their copies in both guarded and unguarded
// branches. Those instructions that have no uses can be just removed.
diff --git a/llvm/lib/Transforms/Utils/BasicBlockUtils.cpp b/llvm/lib/Transforms/Utils/BasicBlockUtils.cpp
index a44746d..606bd8b 100644
--- a/llvm/lib/Transforms/Utils/BasicBlockUtils.cpp
+++ b/llvm/lib/Transforms/Utils/BasicBlockUtils.cpp
@@ -45,22 +45,16 @@
using namespace llvm;
-void llvm::DeleteDeadBlock(BasicBlock *BB, DeferredDominance *DDT) {
+void llvm::DeleteDeadBlock(BasicBlock *BB) {
assert((pred_begin(BB) == pred_end(BB) ||
// Can delete self loop.
BB->getSinglePredecessor() == BB) && "Block is not dead!");
TerminatorInst *BBTerm = BB->getTerminator();
- std::vector<DominatorTree::UpdateType> Updates;
// Loop through all of our successors and make sure they know that one
// of their predecessors is going away.
- if (DDT)
- Updates.reserve(BBTerm->getNumSuccessors());
- for (BasicBlock *Succ : BBTerm->successors()) {
+ for (BasicBlock *Succ : BBTerm->successors())
Succ->removePredecessor(BB);
- if (DDT)
- Updates.push_back({DominatorTree::Delete, BB, Succ});
- }
// Zap all the instructions in the block.
while (!BB->empty()) {
@@ -75,12 +69,8 @@
BB->getInstList().pop_back();
}
- if (DDT) {
- DDT->applyUpdates(Updates);
- DDT->deleteBB(BB); // Deferred deletion of BB.
- } else {
- BB->eraseFromParent(); // Zap the block!
- }
+ // Zap the block!
+ BB->eraseFromParent();
}
void llvm::FoldSingleEntryPHINodes(BasicBlock *BB,
diff --git a/llvm/lib/Transforms/Utils/Local.cpp b/llvm/lib/Transforms/Utils/Local.cpp
index 5b5868c..3ee2d04 100644
--- a/llvm/lib/Transforms/Utils/Local.cpp
+++ b/llvm/lib/Transforms/Utils/Local.cpp
@@ -100,8 +100,7 @@
/// conditions and indirectbr addresses this might make dead if
/// DeleteDeadConditions is true.
bool llvm::ConstantFoldTerminator(BasicBlock *BB, bool DeleteDeadConditions,
- const TargetLibraryInfo *TLI,
- DeferredDominance *DDT) {
+ const TargetLibraryInfo *TLI) {
TerminatorInst *T = BB->getTerminator();
IRBuilder<> Builder(T);
@@ -128,8 +127,6 @@
// Replace the conditional branch with an unconditional one.
Builder.CreateBr(Destination);
BI->eraseFromParent();
- if (DDT)
- DDT->deleteEdge(BB, OldDest);
return true;
}
@@ -200,12 +197,9 @@
createBranchWeights(Weights));
}
// Remove this entry.
- BasicBlock *ParentBB = SI->getParent();
- DefaultDest->removePredecessor(ParentBB);
+ DefaultDest->removePredecessor(SI->getParent());
i = SI->removeCase(i);
e = SI->case_end();
- if (DDT)
- DDT->deleteEdge(ParentBB, DefaultDest);
continue;
}
@@ -231,20 +225,14 @@
// Insert the new branch.
Builder.CreateBr(TheOnlyDest);
BasicBlock *BB = SI->getParent();
- std::vector <DominatorTree::UpdateType> Updates;
- if (DDT)
- Updates.reserve(SI->getNumSuccessors() - 1);
// Remove entries from PHI nodes which we no longer branch to...
for (BasicBlock *Succ : SI->successors()) {
// Found case matching a constant operand?
- if (Succ == TheOnlyDest) {
+ if (Succ == TheOnlyDest)
TheOnlyDest = nullptr; // Don't modify the first branch to TheOnlyDest
- } else {
+ else
Succ->removePredecessor(BB);
- if (DDT)
- Updates.push_back({DominatorTree::Delete, BB, Succ});
- }
}
// Delete the old switch.
@@ -252,8 +240,6 @@
SI->eraseFromParent();
if (DeleteDeadConditions)
RecursivelyDeleteTriviallyDeadInstructions(Cond, TLI);
- if (DDT)
- DDT->applyUpdates(Updates);
return true;
}
@@ -299,23 +285,14 @@
if (BlockAddress *BA =
dyn_cast<BlockAddress>(IBI->getAddress()->stripPointerCasts())) {
BasicBlock *TheOnlyDest = BA->getBasicBlock();
- std::vector <DominatorTree::UpdateType> Updates;
- if (DDT)
- Updates.reserve(IBI->getNumDestinations() - 1);
-
// Insert the new branch.
Builder.CreateBr(TheOnlyDest);
for (unsigned i = 0, e = IBI->getNumDestinations(); i != e; ++i) {
- if (IBI->getDestination(i) == TheOnlyDest) {
+ if (IBI->getDestination(i) == TheOnlyDest)
TheOnlyDest = nullptr;
- } else {
- BasicBlock *ParentBB = IBI->getParent();
- BasicBlock *DestBB = IBI->getDestination(i);
- DestBB->removePredecessor(ParentBB);
- if (DDT)
- Updates.push_back({DominatorTree::Delete, ParentBB, DestBB});
- }
+ else
+ IBI->getDestination(i)->removePredecessor(IBI->getParent());
}
Value *Address = IBI->getAddress();
IBI->eraseFromParent();
@@ -330,8 +307,6 @@
new UnreachableInst(BB->getContext(), BB);
}
- if (DDT)
- DDT->applyUpdates(Updates);
return true;
}
}
@@ -608,8 +583,7 @@
///
/// .. and delete the predecessor corresponding to the '1', this will attempt to
/// recursively fold the and to 0.
-void llvm::RemovePredecessorAndSimplify(BasicBlock *BB, BasicBlock *Pred,
- DeferredDominance *DDT) {
+void llvm::RemovePredecessorAndSimplify(BasicBlock *BB, BasicBlock *Pred) {
// This only adjusts blocks with PHI nodes.
if (!isa<PHINode>(BB->begin()))
return;
@@ -632,18 +606,13 @@
// of the block.
if (PhiIt != OldPhiIt) PhiIt = &BB->front();
}
- if (DDT)
- DDT->deleteEdge(Pred, BB);
}
/// MergeBasicBlockIntoOnlyPred - DestBB is a block with one predecessor and its
/// predecessor is known to have one successor (DestBB!). Eliminate the edge
/// between them, moving the instructions in the predecessor into DestBB and
/// deleting the predecessor block.
-void llvm::MergeBasicBlockIntoOnlyPred(BasicBlock *DestBB, DominatorTree *DT,
- DeferredDominance *DDT) {
- assert(!(DT && DDT) && "Cannot call with both DT and DDT.");
-
+void llvm::MergeBasicBlockIntoOnlyPred(BasicBlock *DestBB, DominatorTree *DT) {
// If BB has single-entry PHI nodes, fold them.
while (PHINode *PN = dyn_cast<PHINode>(DestBB->begin())) {
Value *NewVal = PN->getIncomingValue(0);
@@ -656,23 +625,6 @@
BasicBlock *PredBB = DestBB->getSinglePredecessor();
assert(PredBB && "Block doesn't have a single predecessor!");
- bool ReplaceEntryBB = false;
- if (PredBB == &DestBB->getParent()->getEntryBlock())
- ReplaceEntryBB = true;
-
- // Deferred DT update: Collect all the edges that enter PredBB. These
- // dominator edges will be redirected to DestBB.
- std::vector <DominatorTree::UpdateType> Updates;
- if (DDT && !ReplaceEntryBB) {
- Updates.reserve((2 * std::distance(pred_begin(PredBB), pred_end(PredBB))) +
- 1);
- Updates.push_back({DominatorTree::Delete, PredBB, DestBB});
- for (auto I = pred_begin(PredBB), E = pred_end(PredBB); I != E; ++I) {
- Updates.push_back({DominatorTree::Delete, *I, PredBB});
- Updates.push_back({DominatorTree::Insert, *I, DestBB});
- }
- }
-
// Zap anything that took the address of DestBB. Not doing this will give the
// address an invalid value.
if (DestBB->hasAddressTaken()) {
@@ -693,7 +645,7 @@
// If the PredBB is the entry block of the function, move DestBB up to
// become the entry block after we erase PredBB.
- if (ReplaceEntryBB)
+ if (PredBB == &DestBB->getParent()->getEntryBlock())
DestBB->moveAfter(PredBB);
if (DT) {
@@ -705,19 +657,8 @@
DT->eraseNode(PredBB);
}
}
-
- if (DDT) {
- DDT->deleteBB(PredBB); // Deferred deletion of BB.
- if (ReplaceEntryBB)
- // The entry block was removed and there is no external interface for the
- // dominator tree to be notified of this change. In this corner-case we
- // recalculate the entire tree.
- DDT->recalculate(*(DestBB->getParent()));
- else
- DDT->applyUpdates(Updates);
- } else {
- PredBB->eraseFromParent(); // Nuke BB.
- }
+ // Nuke BB.
+ PredBB->eraseFromParent();
}
/// CanMergeValues - Return true if we can choose one of these values to use
@@ -924,8 +865,7 @@
/// potential side-effect free intrinsics and the branch. If possible,
/// eliminate BB by rewriting all the predecessors to branch to the successor
/// block and return true. If we can't transform, return false.
-bool llvm::TryToSimplifyUncondBranchFromEmptyBlock(BasicBlock *BB,
- DeferredDominance *DDT) {
+bool llvm::TryToSimplifyUncondBranchFromEmptyBlock(BasicBlock *BB) {
assert(BB != &BB->getParent()->getEntryBlock() &&
"TryToSimplifyUncondBranchFromEmptyBlock called on entry block!");
@@ -966,17 +906,6 @@
DEBUG(dbgs() << "Killing Trivial BB: \n" << *BB);
- std::vector<DominatorTree::UpdateType> Updates;
- if (DDT) {
- Updates.reserve((2 * std::distance(pred_begin(BB), pred_end(BB))) + 1);
- Updates.push_back({DominatorTree::Delete, BB, Succ});
- // All predecessors of BB will be moved to Succ.
- for (auto I = pred_begin(BB), E = pred_end(BB); I != E; ++I) {
- Updates.push_back({DominatorTree::Delete, *I, BB});
- Updates.push_back({DominatorTree::Insert, *I, Succ});
- }
- }
-
if (isa<PHINode>(Succ->begin())) {
// If there is more than one pred of succ, and there are PHI nodes in
// the successor, then we need to add incoming edges for the PHI nodes
@@ -1021,13 +950,7 @@
// Everything that jumped to BB now goes to Succ.
BB->replaceAllUsesWith(Succ);
if (!Succ->hasName()) Succ->takeName(BB);
-
- if (DDT) {
- DDT->deleteBB(BB); // Deferred deletion of the old basic block.
- DDT->applyUpdates(Updates);
- } else {
- BB->eraseFromParent(); // Delete the old basic block.
- }
+ BB->eraseFromParent(); // Delete the old basic block.
return true;
}
@@ -1529,19 +1452,13 @@
}
unsigned llvm::changeToUnreachable(Instruction *I, bool UseLLVMTrap,
- bool PreserveLCSSA, DeferredDominance *DDT) {
+ bool PreserveLCSSA) {
BasicBlock *BB = I->getParent();
- std::vector <DominatorTree::UpdateType> Updates;
-
// Loop over all of the successors, removing BB's entry from any PHI
// nodes.
- if (DDT)
- Updates.reserve(BB->getTerminator()->getNumSuccessors());
- for (BasicBlock *Successor : successors(BB)) {
+ for (BasicBlock *Successor : successors(BB))
Successor->removePredecessor(BB, PreserveLCSSA);
- if (DDT)
- Updates.push_back({DominatorTree::Delete, BB, Successor});
- }
+
// Insert a call to llvm.trap right before this. This turns the undefined
// behavior into a hard fail instead of falling through into random code.
if (UseLLVMTrap) {
@@ -1561,13 +1478,11 @@
BB->getInstList().erase(BBI++);
++NumInstrsRemoved;
}
- if (DDT)
- DDT->applyUpdates(Updates);
return NumInstrsRemoved;
}
/// changeToCall - Convert the specified invoke into a normal call.
-static void changeToCall(InvokeInst *II, DeferredDominance *DDT = nullptr) {
+static void changeToCall(InvokeInst *II) {
SmallVector<Value*, 8> Args(II->arg_begin(), II->arg_end());
SmallVector<OperandBundleDef, 1> OpBundles;
II->getOperandBundlesAsDefs(OpBundles);
@@ -1580,16 +1495,11 @@
II->replaceAllUsesWith(NewCall);
// Follow the call by a branch to the normal destination.
- BasicBlock *NormalDestBB = II->getNormalDest();
- BranchInst::Create(NormalDestBB, II);
+ BranchInst::Create(II->getNormalDest(), II);
// Update PHI nodes in the unwind destination
- BasicBlock *BB = II->getParent();
- BasicBlock *UnwindDestBB = II->getUnwindDest();
- UnwindDestBB->removePredecessor(BB);
+ II->getUnwindDest()->removePredecessor(II->getParent());
II->eraseFromParent();
- if (DDT)
- DDT->deleteEdge(BB, UnwindDestBB);
}
BasicBlock *llvm::changeToInvokeAndSplitBasicBlock(CallInst *CI,
@@ -1630,8 +1540,7 @@
}
static bool markAliveBlocks(Function &F,
- SmallPtrSetImpl<BasicBlock*> &Reachable,
- DeferredDominance *DDT = nullptr) {
+ SmallPtrSetImpl<BasicBlock*> &Reachable) {
SmallVector<BasicBlock*, 128> Worklist;
BasicBlock *BB = &F.front();
Worklist.push_back(BB);
@@ -1651,7 +1560,7 @@
if (II->getIntrinsicID() == Intrinsic::assume) {
if (match(II->getArgOperand(0), m_CombineOr(m_Zero(), m_Undef()))) {
// Don't insert a call to llvm.trap right before the unreachable.
- changeToUnreachable(II, false, false, DDT);
+ changeToUnreachable(II, false);
Changed = true;
break;
}
@@ -1668,8 +1577,7 @@
// still be useful for widening.
if (match(II->getArgOperand(0), m_Zero()))
if (!isa<UnreachableInst>(II->getNextNode())) {
- changeToUnreachable(II->getNextNode(), /*UseLLVMTrap=*/false,
- false, DDT);
+ changeToUnreachable(II->getNextNode(), /*UseLLVMTrap=*/ false);
Changed = true;
break;
}
@@ -1679,7 +1587,7 @@
if (auto *CI = dyn_cast<CallInst>(&I)) {
Value *Callee = CI->getCalledValue();
if (isa<ConstantPointerNull>(Callee) || isa<UndefValue>(Callee)) {
- changeToUnreachable(CI, /*UseLLVMTrap=*/false, false, DDT);
+ changeToUnreachable(CI, /*UseLLVMTrap=*/false);
Changed = true;
break;
}
@@ -1689,7 +1597,7 @@
// though.
if (!isa<UnreachableInst>(CI->getNextNode())) {
// Don't insert a call to llvm.trap right before the unreachable.
- changeToUnreachable(CI->getNextNode(), false, false, DDT);
+ changeToUnreachable(CI->getNextNode(), false);
Changed = true;
}
break;
@@ -1708,7 +1616,7 @@
if (isa<UndefValue>(Ptr) ||
(isa<ConstantPointerNull>(Ptr) &&
SI->getPointerAddressSpace() == 0)) {
- changeToUnreachable(SI, true, false, DDT);
+ changeToUnreachable(SI, true);
Changed = true;
break;
}
@@ -1720,20 +1628,16 @@
// Turn invokes that call 'nounwind' functions into ordinary calls.
Value *Callee = II->getCalledValue();
if (isa<ConstantPointerNull>(Callee) || isa<UndefValue>(Callee)) {
- changeToUnreachable(II, true, false, DDT);
+ changeToUnreachable(II, true);
Changed = true;
} else if (II->doesNotThrow() && canSimplifyInvokeNoUnwind(&F)) {
if (II->use_empty() && II->onlyReadsMemory()) {
// jump to the normal destination branch.
- BasicBlock *NormalDestBB = II->getNormalDest();
- BasicBlock *UnwindDestBB = II->getUnwindDest();
- BranchInst::Create(NormalDestBB, II);
- UnwindDestBB->removePredecessor(II->getParent());
+ BranchInst::Create(II->getNormalDest(), II);
+ II->getUnwindDest()->removePredecessor(II->getParent());
II->eraseFromParent();
- if (DDT)
- DDT->deleteEdge(BB, UnwindDestBB);
} else
- changeToCall(II, DDT);
+ changeToCall(II);
Changed = true;
}
} else if (auto *CatchSwitch = dyn_cast<CatchSwitchInst>(Terminator)) {
@@ -1779,7 +1683,7 @@
}
}
- Changed |= ConstantFoldTerminator(BB, true, nullptr, DDT);
+ Changed |= ConstantFoldTerminator(BB, true);
for (BasicBlock *Successor : successors(BB))
if (Reachable.insert(Successor).second)
Worklist.push_back(Successor);
@@ -1787,11 +1691,11 @@
return Changed;
}
-void llvm::removeUnwindEdge(BasicBlock *BB, DeferredDominance *DDT) {
+void llvm::removeUnwindEdge(BasicBlock *BB) {
TerminatorInst *TI = BB->getTerminator();
if (auto *II = dyn_cast<InvokeInst>(TI)) {
- changeToCall(II, DDT);
+ changeToCall(II);
return;
}
@@ -1819,18 +1723,15 @@
UnwindDest->removePredecessor(BB);
TI->replaceAllUsesWith(NewTI);
TI->eraseFromParent();
- if (DDT)
- DDT->deleteEdge(BB, UnwindDest);
}
/// removeUnreachableBlocks - Remove blocks that are not reachable, even
/// if they are in a dead cycle. Return true if a change was made, false
/// otherwise. If `LVI` is passed, this function preserves LazyValueInfo
/// after modifying the CFG.
-bool llvm::removeUnreachableBlocks(Function &F, LazyValueInfo *LVI,
- DeferredDominance *DDT) {
+bool llvm::removeUnreachableBlocks(Function &F, LazyValueInfo *LVI) {
SmallPtrSet<BasicBlock*, 16> Reachable;
- bool Changed = markAliveBlocks(F, Reachable, DDT);
+ bool Changed = markAliveBlocks(F, Reachable);
// If there are unreachable blocks in the CFG...
if (Reachable.size() == F.size())
@@ -1840,39 +1741,25 @@
NumRemoved += F.size()-Reachable.size();
// Loop over all of the basic blocks that are not reachable, dropping all of
- // their internal references. Update DDT and LVI if available.
- std::vector <DominatorTree::UpdateType> Updates;
- for (Function::iterator I = ++F.begin(), E = F.end(); I != E; ++I) {
- auto *BB = &*I;
- if (Reachable.count(BB))
+ // their internal references...
+ for (Function::iterator BB = ++F.begin(), E = F.end(); BB != E; ++BB) {
+ if (Reachable.count(&*BB))
continue;
- for (BasicBlock *Successor : successors(BB)) {
+
+ for (BasicBlock *Successor : successors(&*BB))
if (Reachable.count(Successor))
- Successor->removePredecessor(BB);
- if (DDT)
- Updates.push_back({DominatorTree::Delete, BB, Successor});
- }
+ Successor->removePredecessor(&*BB);
if (LVI)
- LVI->eraseBlock(BB);
+ LVI->eraseBlock(&*BB);
BB->dropAllReferences();
}
- for (Function::iterator I = ++F.begin(); I != F.end();) {
- auto *BB = &*I;
- if (Reachable.count(BB)) {
- ++I;
- continue;
- }
- if (DDT) {
- DDT->deleteBB(BB); // deferred deletion of BB.
- ++I;
- } else {
+ for (Function::iterator I = ++F.begin(); I != F.end();)
+ if (!Reachable.count(&*I))
I = F.getBasicBlockList().erase(I);
- }
- }
+ else
+ ++I;
- if (DDT)
- DDT->applyUpdates(Updates);
return true;
}