diff options
Diffstat (limited to 'llvm/lib/Transforms/Utils/BasicBlockUtils.cpp')
| -rw-r--r-- | llvm/lib/Transforms/Utils/BasicBlockUtils.cpp | 114 |
1 files changed, 3 insertions, 111 deletions
diff --git a/llvm/lib/Transforms/Utils/BasicBlockUtils.cpp b/llvm/lib/Transforms/Utils/BasicBlockUtils.cpp index 2c7545173bc..58a5f5e1443 100644 --- a/llvm/lib/Transforms/Utils/BasicBlockUtils.cpp +++ b/llvm/lib/Transforms/Utils/BasicBlockUtils.cpp @@ -31,8 +31,6 @@ #include <algorithm> using namespace llvm; -/// DeleteDeadBlock - Delete the specified block, which must have no -/// predecessors. void llvm::DeleteDeadBlock(BasicBlock *BB) { assert((pred_begin(BB) == pred_end(BB) || // Can delete self loop. @@ -61,10 +59,6 @@ void llvm::DeleteDeadBlock(BasicBlock *BB) { BB->eraseFromParent(); } -/// FoldSingleEntryPHINodes - We know that BB has one predecessor. If there are -/// any single-entry PHI nodes in it, fold them away. This handles the case -/// when all entries to the PHI nodes in a block are guaranteed equal, such as -/// when the block has exactly one predecessor. void llvm::FoldSingleEntryPHINodes(BasicBlock *BB, MemoryDependenceResults *MemDep) { if (!isa<PHINode>(BB->begin())) return; @@ -82,11 +76,6 @@ void llvm::FoldSingleEntryPHINodes(BasicBlock *BB, } } - -/// DeleteDeadPHIs - Examine each PHI in the given block and delete it if it -/// is dead. Also recursively delete any operands that become dead as -/// a result. This includes tracing the def-use list from the PHI to see if -/// it is ultimately unused or if it reaches an unused cycle. bool llvm::DeleteDeadPHIs(BasicBlock *BB, const TargetLibraryInfo *TLI) { // Recursively deleting a PHI may cause multiple PHIs to be deleted // or RAUW'd undef, so use an array of WeakVH for the PHIs to delete. @@ -103,8 +92,6 @@ bool llvm::DeleteDeadPHIs(BasicBlock *BB, const TargetLibraryInfo *TLI) { return Changed; } -/// MergeBlockIntoPredecessor - Attempts to merge a block into its predecessor, -/// if possible. The return value indicates success or failure. bool llvm::MergeBlockIntoPredecessor(BasicBlock *BB, DominatorTree *DT, LoopInfo *LI, MemoryDependenceResults *MemDep) { @@ -183,9 +170,6 @@ bool llvm::MergeBlockIntoPredecessor(BasicBlock *BB, DominatorTree *DT, return true; } -/// ReplaceInstWithValue - Replace all uses of an instruction (specified by BI) -/// with a value, then remove and delete the original instruction. -/// void llvm::ReplaceInstWithValue(BasicBlock::InstListType &BIL, BasicBlock::iterator &BI, Value *V) { Instruction &I = *BI; @@ -200,11 +184,6 @@ void llvm::ReplaceInstWithValue(BasicBlock::InstListType &BIL, BI = BIL.erase(BI); } - -/// ReplaceInstWithInst - Replace the instruction specified by BI with the -/// instruction specified by I. The original instruction is deleted and BI is -/// updated to point to the new instruction. -/// void llvm::ReplaceInstWithInst(BasicBlock::InstListType &BIL, BasicBlock::iterator &BI, Instruction *I) { assert(I->getParent() == nullptr && @@ -225,16 +204,11 @@ void llvm::ReplaceInstWithInst(BasicBlock::InstListType &BIL, BI = New; } -/// ReplaceInstWithInst - Replace the instruction specified by From with the -/// instruction specified by To. -/// void llvm::ReplaceInstWithInst(Instruction *From, Instruction *To) { BasicBlock::iterator BI(From); ReplaceInstWithInst(From->getParent()->getInstList(), BI, To); } -/// SplitEdge - Split the edge connecting specified block. Pass P must -/// not be NULL. BasicBlock *llvm::SplitEdge(BasicBlock *BB, BasicBlock *Succ, DominatorTree *DT, LoopInfo *LI) { unsigned SuccNum = GetSuccessorNumber(BB, Succ); @@ -276,11 +250,6 @@ llvm::SplitAllCriticalEdges(Function &F, return NumBroken; } -/// SplitBlock - Split the specified block at the specified instruction - every -/// thing before SplitPt stays in Old and everything starting with SplitPt moves -/// to a new block. The two blocks are joined by an unconditional branch and -/// the loop info is updated. -/// BasicBlock *llvm::SplitBlock(BasicBlock *Old, Instruction *SplitPt, DominatorTree *DT, LoopInfo *LI) { BasicBlock::iterator SplitIt = SplitPt->getIterator(); @@ -311,8 +280,7 @@ BasicBlock *llvm::SplitBlock(BasicBlock *Old, Instruction *SplitPt, return New; } -/// UpdateAnalysisInformation - Update DominatorTree, LoopInfo, and LCCSA -/// analysis information. +/// Update DominatorTree, LoopInfo, and LCCSA analysis information. static void UpdateAnalysisInformation(BasicBlock *OldBB, BasicBlock *NewBB, ArrayRef<BasicBlock *> Preds, DominatorTree *DT, LoopInfo *LI, @@ -388,8 +356,8 @@ static void UpdateAnalysisInformation(BasicBlock *OldBB, BasicBlock *NewBB, } } -/// UpdatePHINodes - Update the PHI nodes in OrigBB to include the values coming -/// from NewBB. This also updates AliasAnalysis, if available. +/// Update the PHI nodes in OrigBB to include the values coming from NewBB. +/// This also updates AliasAnalysis, if available. static void UpdatePHINodes(BasicBlock *OrigBB, BasicBlock *NewBB, ArrayRef<BasicBlock *> Preds, BranchInst *BI, bool HasLoopExit) { @@ -456,21 +424,6 @@ static void UpdatePHINodes(BasicBlock *OrigBB, BasicBlock *NewBB, } } -/// SplitBlockPredecessors - This method introduces at least one new basic block -/// into the function and moves some of the predecessors of BB to be -/// predecessors of the new block. The new predecessors are indicated by the -/// Preds array. The new block is given a suffix of 'Suffix'. Returns new basic -/// block to which predecessors from Preds are now pointing. -/// -/// If BB is a landingpad block then additional basicblock might be introduced. -/// It will have suffix of 'Suffix'+".split_lp". -/// See SplitLandingPadPredecessors for more details on this case. -/// -/// This currently updates the LLVM IR, AliasAnalysis, DominatorTree, -/// LoopInfo, and LCCSA but no other analyses. In particular, it does not -/// preserve LoopSimplify (because it's complicated to handle the case where one -/// of the edges being split is an exit of a loop with other exits). -/// BasicBlock *llvm::SplitBlockPredecessors(BasicBlock *BB, ArrayRef<BasicBlock *> Preds, const char *Suffix, DominatorTree *DT, @@ -529,19 +482,6 @@ BasicBlock *llvm::SplitBlockPredecessors(BasicBlock *BB, return NewBB; } -/// SplitLandingPadPredecessors - This method transforms the landing pad, -/// OrigBB, by introducing two new basic blocks into the function. One of those -/// new basic blocks gets the predecessors listed in Preds. The other basic -/// block gets the remaining predecessors of OrigBB. The landingpad instruction -/// OrigBB is clone into both of the new basic blocks. The new blocks are given -/// the suffixes 'Suffix1' and 'Suffix2', and are returned in the NewBBs vector. -/// -/// This currently updates the LLVM IR, AliasAnalysis, DominatorTree, -/// DominanceFrontier, LoopInfo, and LCCSA but no other analyses. In particular, -/// it does not preserve LoopSimplify (because it's complicated to handle the -/// case where one of the edges being split is an exit of a loop with other -/// exits). -/// void llvm::SplitLandingPadPredecessors(BasicBlock *OrigBB, ArrayRef<BasicBlock *> Preds, const char *Suffix1, const char *Suffix2, @@ -646,11 +586,6 @@ void llvm::SplitLandingPadPredecessors(BasicBlock *OrigBB, } } -/// FoldReturnIntoUncondBranch - This method duplicates the specified return -/// instruction into a predecessor which ends in an unconditional branch. If -/// the return instruction returns a value defined by a PHI, propagate the -/// right value into the return. It returns the new return instruction in the -/// predecessor. ReturnInst *llvm::FoldReturnIntoUncondBranch(ReturnInst *RI, BasicBlock *BB, BasicBlock *Pred) { Instruction *UncondBranch = Pred->getTerminator(); @@ -689,26 +624,6 @@ ReturnInst *llvm::FoldReturnIntoUncondBranch(ReturnInst *RI, BasicBlock *BB, return cast<ReturnInst>(NewRet); } -/// SplitBlockAndInsertIfThen - Split the containing block at the -/// specified instruction - everything before and including SplitBefore stays -/// in the old basic block, and everything after SplitBefore is moved to a -/// new block. The two blocks are connected by a conditional branch -/// (with value of Cmp being the condition). -/// Before: -/// Head -/// SplitBefore -/// Tail -/// After: -/// Head -/// if (Cond) -/// ThenBlock -/// SplitBefore -/// Tail -/// -/// If Unreachable is true, then ThenBlock ends with -/// UnreachableInst, otherwise it branches to Tail. -/// Returns the NewBasicBlock's terminator. - TerminatorInst * llvm::SplitBlockAndInsertIfThen(Value *Cond, Instruction *SplitBefore, bool Unreachable, MDNode *BranchWeights, @@ -751,20 +666,6 @@ llvm::SplitBlockAndInsertIfThen(Value *Cond, Instruction *SplitBefore, return CheckTerm; } -/// SplitBlockAndInsertIfThenElse is similar to SplitBlockAndInsertIfThen, -/// but also creates the ElseBlock. -/// Before: -/// Head -/// SplitBefore -/// Tail -/// After: -/// Head -/// if (Cond) -/// ThenBlock -/// else -/// ElseBlock -/// SplitBefore -/// Tail void llvm::SplitBlockAndInsertIfThenElse(Value *Cond, Instruction *SplitBefore, TerminatorInst **ThenTerm, TerminatorInst **ElseTerm, @@ -786,15 +687,6 @@ void llvm::SplitBlockAndInsertIfThenElse(Value *Cond, Instruction *SplitBefore, } -/// GetIfCondition - Given a basic block (BB) with two predecessors, -/// check to see if the merge at this block is due -/// to an "if condition". If so, return the boolean condition that determines -/// which entry into BB will be taken. Also, return by references the block -/// that will be entered from if the condition is true, and the block that will -/// be entered if the condition is false. -/// -/// This does no checking to see if the true/false blocks have large or unsavory -/// instructions in them. Value *llvm::GetIfCondition(BasicBlock *BB, BasicBlock *&IfTrue, BasicBlock *&IfFalse) { PHINode *SomePHI = dyn_cast<PHINode>(BB->begin()); |
