X-Git-Url: http://plrg.eecs.uci.edu/git/?a=blobdiff_plain;f=lib%2FTransforms%2FScalar%2FCorrelatedExprs.cpp;h=8d369f2870e4dee0af458ab898493be3ed57052b;hb=e4d87aa2de6e52952dca73716386db09aad5a8fd;hp=2ff504de6c0c866d05b46f838cc39357ca4c86d7;hpb=a92f696b74a99325026ebbdbffd2a44317e0c10b;p=oota-llvm.git diff --git a/lib/Transforms/Scalar/CorrelatedExprs.cpp b/lib/Transforms/Scalar/CorrelatedExprs.cpp index 2ff504de6c0..8d369f2870e 100644 --- a/lib/Transforms/Scalar/CorrelatedExprs.cpp +++ b/lib/Transforms/Scalar/CorrelatedExprs.cpp @@ -1,12 +1,19 @@ //===- CorrelatedExprs.cpp - Pass to detect and eliminated c.e.'s ---------===// // -// Correlated Expression Elimination propogates information from conditional -// branches to blocks dominated by destinations of the branch. It propogates +// The LLVM Compiler Infrastructure +// +// This file was developed by the LLVM research group and is distributed under +// the University of Illinois Open Source License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// +// +// Correlated Expression Elimination propagates information from conditional +// branches to blocks dominated by destinations of the branch. It propagates // information from the condition check itself into the body of the branch, // allowing transformations like these for example: // // if (i == 7) -// ... 4*i; // constant propogation +// ... 4*i; // constant propagation // // M = i+1; N = j+1; // if (i == j) @@ -19,52 +26,55 @@ // //===----------------------------------------------------------------------===// +#define DEBUG_TYPE "cee" #include "llvm/Transforms/Scalar.h" +#include "llvm/Constants.h" #include "llvm/Pass.h" #include "llvm/Function.h" -#include "llvm/iTerminators.h" -#include "llvm/iPHINode.h" -#include "llvm/iOperators.h" -#include "llvm/ConstantHandling.h" -#include "llvm/Assembly/Writer.h" +#include "llvm/Instructions.h" +#include "llvm/Type.h" #include "llvm/Analysis/Dominators.h" +#include "llvm/Assembly/Writer.h" #include "llvm/Transforms/Utils/Local.h" +#include "llvm/Transforms/Utils/BasicBlockUtils.h" #include "llvm/Support/ConstantRange.h" #include "llvm/Support/CFG.h" -#include "Support/PostOrderIterator.h" -#include "Support/Statistic.h" +#include "llvm/Support/Debug.h" +#include "llvm/ADT/PostOrderIterator.h" +#include "llvm/ADT/Statistic.h" #include +using namespace llvm; -namespace { - Statistic<> NumSetCCRemoved("cee", "Number of setcc instruction eliminated"); - Statistic<> NumOperandsCann("cee", "Number of operands cannonicalized"); - Statistic<> BranchRevectors("cee", "Number of branches revectored"); +STATISTIC(NumCmpRemoved, "Number of cmp instruction eliminated"); +STATISTIC(NumOperandsCann, "Number of operands canonicalized"); +STATISTIC(BranchRevectors, "Number of branches revectored"); +namespace { class ValueInfo; class Relation { - Value *Val; // Relation to what value? - Instruction::BinaryOps Rel; // SetCC relation, or Add if no information + Value *Val; // Relation to what value? + unsigned Rel; // SetCC or ICmp relation, or Add if no information public: Relation(Value *V) : Val(V), Rel(Instruction::Add) {} bool operator<(const Relation &R) const { return Val < R.Val; } Value *getValue() const { return Val; } - Instruction::BinaryOps getRelation() const { return Rel; } + unsigned getRelation() const { return Rel; } // contradicts - Return true if the relationship specified by the operand // contradicts already known information. // - bool contradicts(Instruction::BinaryOps Rel, const ValueInfo &VI) const; + bool contradicts(unsigned Rel, const ValueInfo &VI) const; // incorporate - Incorporate information in the argument into this relation // entry. This assumes that the information doesn't contradict itself. If // any new information is gained, true is returned, otherwise false is // returned to indicate that nothing was updated. // - bool incorporate(Instruction::BinaryOps Rel, ValueInfo &VI); + bool incorporate(unsigned Rel, ValueInfo &VI); // KnownResult - Whether or not this condition determines the result of a - // setcc in the program. False & True are intentionally 0 & 1 so we can - // convert to bool by casting after checking for unknown. + // setcc or icmp in the program. False & True are intentionally 0 & 1 + // so we can convert to bool by casting after checking for unknown. // enum KnownResult { KnownFalse = 0, KnownTrue = 1, Unknown = 2 }; @@ -72,7 +82,7 @@ namespace { // the specified relationship is true or false, return that. If we cannot // determine the result required, return Unknown. // - KnownResult getImpliedResult(Instruction::BinaryOps Rel) const; + KnownResult getImpliedResult(unsigned Rel) const; // print - Output this relation to the specified stream void print(std::ostream &OS) const; @@ -91,7 +101,7 @@ namespace { // kept sorted by the Val field. std::vector Relationships; - // If information about this value is known or propogated from constant + // If information about this value is known or propagated from constant // expressions, this range contains the possible values this value may hold. ConstantRange Bounds; @@ -120,12 +130,13 @@ namespace { void setReplacement(Value *Repl) { Replacement = Repl; } // getRelation - return the relationship entry for the specified value. - // This can invalidate references to other Relation's, so use it carefully. + // This can invalidate references to other Relations, so use it carefully. // Relation &getRelation(Value *V) { // Binary search for V's entry... std::vector::iterator I = - std::lower_bound(Relationships.begin(), Relationships.end(), V); + std::lower_bound(Relationships.begin(), Relationships.end(), + Relation(V)); // If we found the entry, return it... if (I != Relationships.end() && I->getValue() == V) @@ -138,7 +149,8 @@ namespace { const Relation *requestRelation(Value *V) const { // Binary search for V's entry... std::vector::const_iterator I = - std::lower_bound(Relationships.begin(), Relationships.end(), V); + std::lower_bound(Relationships.begin(), Relationships.end(), + Relation(V)); if (I != Relationships.end() && I->getValue() == V) return &*I; return 0; @@ -167,6 +179,9 @@ namespace { // this region. BasicBlock *getEntryBlock() const { return BB; } + // empty - return true if this region has no information known about it. + bool empty() const { return ValueMap.empty(); } + const RegionInfo &operator=(const RegionInfo &RI) { ValueMap = RI.ValueMap; return *this; @@ -174,6 +189,7 @@ namespace { // print - Output information about this region... void print(std::ostream &OS) const; + void dump() const; // Allow external access. typedef ValueMapTy::iterator iterator; @@ -191,20 +207,27 @@ namespace { if (I != ValueMap.end()) return &I->second; return 0; } + + /// removeValueInfo - Remove anything known about V from our records. This + /// works whether or not we know anything about V. + /// + void removeValueInfo(Value *V) { + ValueMap.erase(V); + } }; /// CEE - Correlated Expression Elimination class CEE : public FunctionPass { std::map RankMap; std::map RegionInfoMap; - DominatorSet *DS; + ETForest *EF; DominatorTree *DT; public: virtual bool runOnFunction(Function &F); // We don't modify the program, so we preserve all analyses virtual void getAnalysisUsage(AnalysisUsage &AU) const { - AU.addRequired(); + AU.addRequired(); AU.addRequired(); AU.addRequiredID(BreakCriticalEdgesID); }; @@ -223,7 +246,7 @@ namespace { void BuildRankMap(Function &F); unsigned getRank(Value *V) const { - if (isa(V) || isa(V)) return 0; + if (isa(V)) return 0; std::map::const_iterator I = RankMap.find(V); if (I != RankMap.end()) return I->second; return 0; // Must be some other global thing @@ -231,30 +254,41 @@ namespace { bool TransformRegion(BasicBlock *BB, std::set &VisitedBlocks); - BasicBlock *isCorrelatedBranchBlock(BasicBlock *BB, RegionInfo &RI); - void PropogateBranchInfo(BranchInst *BI); - void PropogateEquality(Value *Op0, Value *Op1, RegionInfo &RI); - void PropogateRelation(Instruction::BinaryOps Opcode, Value *Op0, + bool ForwardCorrelatedEdgeDestination(TerminatorInst *TI, unsigned SuccNo, + RegionInfo &RI); + + void ForwardSuccessorTo(TerminatorInst *TI, unsigned Succ, BasicBlock *D, + RegionInfo &RI); + void ReplaceUsesOfValueInRegion(Value *Orig, Value *New, + BasicBlock *RegionDominator); + void CalculateRegionExitBlocks(BasicBlock *BB, BasicBlock *OldSucc, + std::vector &RegionExitBlocks); + void InsertRegionExitMerges(PHINode *NewPHI, Instruction *OldVal, + const std::vector &RegionExitBlocks); + + void PropagateBranchInfo(BranchInst *BI); + void PropagateSwitchInfo(SwitchInst *SI); + void PropagateEquality(Value *Op0, Value *Op1, RegionInfo &RI); + void PropagateRelation(unsigned Opcode, Value *Op0, Value *Op1, RegionInfo &RI); void UpdateUsersOfValue(Value *V, RegionInfo &RI); void IncorporateInstruction(Instruction *Inst, RegionInfo &RI); void ComputeReplacements(RegionInfo &RI); - - // getSetCCResult - Given a setcc instruction, determine if the result is + // getCmpResult - Given a icmp instruction, determine if the result is // determined by facts we already know about the region under analysis. - // Return KnownTrue, KnownFalse, or Unknown based on what we can determine. - // - Relation::KnownResult getSetCCResult(SetCondInst *SC, const RegionInfo &RI); - + // Return KnownTrue, KnownFalse, or UnKnown based on what we can determine. + Relation::KnownResult getCmpResult(CmpInst *ICI, const RegionInfo &RI); bool SimplifyBasicBlock(BasicBlock &BB, const RegionInfo &RI); bool SimplifyInstruction(Instruction *Inst, const RegionInfo &RI); - }; - RegisterOpt X("cee", "Correlated Expression Elimination"); + }; + RegisterPass X("cee", "Correlated Expression Elimination"); } -Pass *createCorrelatedExpressionEliminationPass() { return new CEE(); } +FunctionPass *llvm::createCorrelatedExpressionEliminationPass() { + return new CEE(); +} bool CEE::runOnFunction(Function &F) { @@ -264,11 +298,11 @@ bool CEE::runOnFunction(Function &F) { // Traverse the dominator tree, computing information for each node in the // tree. Note that our traversal will not even touch unreachable basic // blocks. - DS = &getAnalysis(); + EF = &getAnalysis(); DT = &getAnalysis(); - + std::set VisitedBlocks; - bool Changed = TransformRegion(&F.getEntryNode(), VisitedBlocks); + bool Changed = TransformRegion(&F.getEntryBlock(), VisitedBlocks); RegionInfoMap.clear(); RankMap.clear(); @@ -278,7 +312,7 @@ bool CEE::runOnFunction(Function &F) { // TransformRegion - Transform the region starting with BB according to the // calculated region information for the block. Transforming the region // involves analyzing any information this block provides to successors, -// propogating the information to successors, and finally transforming +// propagating the information to successors, and finally transforming // successors. // // This method processes the function in depth first order, which guarantees @@ -299,7 +333,7 @@ bool CEE::TransformRegion(BasicBlock *BB, std::set &VisitedBlocks){ ComputeReplacements(RI); // If debugging, print computed region information... - DEBUG(RI.print(std::cerr)); + DEBUG(RI.print(*cerr.stream())); // Simplify the contents of this block... bool Changed = SimplifyBasicBlock(*BB, RI); @@ -309,90 +343,410 @@ bool CEE::TransformRegion(BasicBlock *BB, std::set &VisitedBlocks){ // Loop over all of the blocks that this block is the immediate dominator for. // Because all information known in this region is also known in all of the - // blocks that are dominated by this one, we can safely propogate the + // blocks that are dominated by this one, we can safely propagate the // information down now. // DominatorTree::Node *BBN = (*DT)[BB]; - for (unsigned i = 0, e = BBN->getChildren().size(); i != e; ++i) { - BasicBlock *Dominated = BBN->getChildren()[i]->getNode(); - assert(RegionInfoMap.find(Dominated) == RegionInfoMap.end() && - "RegionInfo should be calculated in dominanace order!"); - getRegionInfo(Dominated) = RI; - } + if (!RI.empty()) // Time opt: only propagate if we can change something + for (unsigned i = 0, e = BBN->getChildren().size(); i != e; ++i) { + BasicBlock *Dominated = BBN->getChildren()[i]->getBlock(); + assert(RegionInfoMap.find(Dominated) == RegionInfoMap.end() && + "RegionInfo should be calculated in dominanace order!"); + getRegionInfo(Dominated) = RI; + } // Now that all of our successors have information if they deserve it, - // propogate any information our terminator instruction finds to our + // propagate any information our terminator instruction finds to our // successors. - if (BranchInst *BI = dyn_cast(TI)) + if (BranchInst *BI = dyn_cast(TI)) { if (BI->isConditional()) - PropogateBranchInfo(BI); + PropagateBranchInfo(BI); + } else if (SwitchInst *SI = dyn_cast(TI)) { + PropagateSwitchInfo(SI); + } // If this is a branch to a block outside our region that simply performs // another conditional branch, one whose outcome is known inside of this // region, then vector this outgoing edge directly to the known destination. // for (unsigned i = 0, e = TI->getNumSuccessors(); i != e; ++i) - while (BasicBlock *Dest = isCorrelatedBranchBlock(TI->getSuccessor(i), RI)){ - // If there are any PHI nodes in the Dest BB, we must duplicate the entry - // in the PHI node for the old successor to now include an entry from the - // current basic block. - // - BasicBlock *OldSucc = TI->getSuccessor(i); - - // Loop over all of the PHI nodes... - for (BasicBlock::iterator I = Dest->begin(); - PHINode *PN = dyn_cast(&*I); ++I) { - // Find the entry in the PHI node for OldSucc, create a duplicate entry - // for BB now. - int BlockIndex = PN->getBasicBlockIndex(OldSucc); - assert(BlockIndex != -1 && "Block should have entry in PHI!"); - PN->addIncoming(PN->getIncomingValue(BlockIndex), BB); - } - - // Actually revector the branch now... - TI->setSuccessor(i, Dest); + while (ForwardCorrelatedEdgeDestination(TI, i, RI)) { ++BranchRevectors; Changed = true; } // Now that all of our successors have information, recursively process them. for (unsigned i = 0, e = BBN->getChildren().size(); i != e; ++i) - Changed |= TransformRegion(BBN->getChildren()[i]->getNode(), VisitedBlocks); + Changed |= TransformRegion(BBN->getChildren()[i]->getBlock(),VisitedBlocks); return Changed; } -// If this block is a simple block not in the current region, which contains -// only a conditional branch, we determine if the outcome of the branch can be -// determined from information inside of the region. Instead of going to this -// block, we can instead go to the destination we know is the right target. +// isBlockSimpleEnoughForCheck to see if the block is simple enough for us to +// revector the conditional branch in the bottom of the block, do so now. // -BasicBlock *CEE::isCorrelatedBranchBlock(BasicBlock *BB, RegionInfo &RI) { +static bool isBlockSimpleEnough(BasicBlock *BB) { + assert(isa(BB->getTerminator())); + BranchInst *BI = cast(BB->getTerminator()); + assert(BI->isConditional()); + + // Check the common case first: empty block, or block with just a setcc. + if (BB->size() == 1 || + (BB->size() == 2 && &BB->front() == BI->getCondition() && + BI->getCondition()->hasOneUse())) + return true; + + // Check the more complex case now... + BasicBlock::iterator I = BB->begin(); + + // FIXME: This should be reenabled once the regression with SIM is fixed! +#if 0 + // PHI Nodes are ok, just skip over them... + while (isa(*I)) ++I; +#endif + + // Accept the setcc instruction... + if (&*I == BI->getCondition()) + ++I; + + // Nothing else is acceptable here yet. We must not revector... unless we are + // at the terminator instruction. + if (&*I == BI) + return true; + + return false; +} + + +bool CEE::ForwardCorrelatedEdgeDestination(TerminatorInst *TI, unsigned SuccNo, + RegionInfo &RI) { + // If this successor is a simple block not in the current region, which + // contains only a conditional branch, we decide if the outcome of the branch + // can be determined from information inside of the region. Instead of going + // to this block, we can instead go to the destination we know is the right + // target. + // + // Check to see if we dominate the block. If so, this block will get the // condition turned to a constant anyway. // - //if (DS->dominates(RI.getEntryBlock(), BB)) + //if (EF->dominates(RI.getEntryBlock(), BB)) // return 0; - // Check to see if this is a conditional branch... - if (BranchInst *BI = dyn_cast(BB->getTerminator())) - if (BI->isConditional()) { - // Make sure that the block is either empty, or only contains a setcc. - if (BB->size() == 1 || - (BB->size() == 2 && &BB->front() == BI->getCondition() && - BI->getCondition()->use_size() == 1)) - if (SetCondInst *SCI = dyn_cast(BI->getCondition())) { - Relation::KnownResult Result = getSetCCResult(SCI, RI); - - if (Result == Relation::KnownTrue) - return BI->getSuccessor(0); - else if (Result == Relation::KnownFalse) - return BI->getSuccessor(1); - } + BasicBlock *BB = TI->getParent(); + + // Get the destination block of this edge... + BasicBlock *OldSucc = TI->getSuccessor(SuccNo); + + // Make sure that the block ends with a conditional branch and is simple + // enough for use to be able to revector over. + BranchInst *BI = dyn_cast(OldSucc->getTerminator()); + if (BI == 0 || !BI->isConditional() || !isBlockSimpleEnough(OldSucc)) + return false; + + // We can only forward the branch over the block if the block ends with a + // cmp we can determine the outcome for. + // + // FIXME: we can make this more generic. Code below already handles more + // generic case. + if (!isa(BI->getCondition())) + return false; + + // Make a new RegionInfo structure so that we can simulate the effect of the + // PHI nodes in the block we are skipping over... + // + RegionInfo NewRI(RI); + + // Remove value information for all of the values we are simulating... to make + // sure we don't have any stale information. + for (BasicBlock::iterator I = OldSucc->begin(), E = OldSucc->end(); I!=E; ++I) + if (I->getType() != Type::VoidTy) + NewRI.removeValueInfo(I); + + // Put the newly discovered information into the RegionInfo... + for (BasicBlock::iterator I = OldSucc->begin(), E = OldSucc->end(); I!=E; ++I) + if (PHINode *PN = dyn_cast(I)) { + int OpNum = PN->getBasicBlockIndex(BB); + assert(OpNum != -1 && "PHI doesn't have incoming edge for predecessor!?"); + PropagateEquality(PN, PN->getIncomingValue(OpNum), NewRI); + } else if (CmpInst *CI = dyn_cast(I)) { + Relation::KnownResult Res = getCmpResult(CI, NewRI); + if (Res == Relation::Unknown) return false; + PropagateEquality(CI, ConstantBool::get(Res), NewRI); + } else { + assert(isa(*I) && "Unexpected instruction type!"); + } + + // Compute the facts implied by what we have discovered... + ComputeReplacements(NewRI); + + ValueInfo &PredicateVI = NewRI.getValueInfo(BI->getCondition()); + if (PredicateVI.getReplacement() && + isa(PredicateVI.getReplacement()) && + !isa(PredicateVI.getReplacement())) { + ConstantBool *CB = cast(PredicateVI.getReplacement()); + + // Forward to the successor that corresponds to the branch we will take. + ForwardSuccessorTo(TI, SuccNo, BI->getSuccessor(!CB->getValue()), NewRI); + return true; + } + + return false; +} + +static Value *getReplacementOrValue(Value *V, RegionInfo &RI) { + if (const ValueInfo *VI = RI.requestValueInfo(V)) + if (Value *Repl = VI->getReplacement()) + return Repl; + return V; +} + +/// ForwardSuccessorTo - We have found that we can forward successor # 'SuccNo' +/// of Terminator 'TI' to the 'Dest' BasicBlock. This method performs the +/// mechanics of updating SSA information and revectoring the branch. +/// +void CEE::ForwardSuccessorTo(TerminatorInst *TI, unsigned SuccNo, + BasicBlock *Dest, RegionInfo &RI) { + // If there are any PHI nodes in the Dest BB, we must duplicate the entry + // in the PHI node for the old successor to now include an entry from the + // current basic block. + // + BasicBlock *OldSucc = TI->getSuccessor(SuccNo); + BasicBlock *BB = TI->getParent(); + + DOUT << "Forwarding branch in basic block %" << BB->getName() + << " from block %" << OldSucc->getName() << " to block %" + << Dest->getName() << "\n" + << "Before forwarding: " << *BB->getParent(); + + // Because we know that there cannot be critical edges in the flow graph, and + // that OldSucc has multiple outgoing edges, this means that Dest cannot have + // multiple incoming edges. + // +#ifndef NDEBUG + pred_iterator DPI = pred_begin(Dest); ++DPI; + assert(DPI == pred_end(Dest) && "Critical edge found!!"); +#endif + + // Loop over any PHI nodes in the destination, eliminating them, because they + // may only have one input. + // + while (PHINode *PN = dyn_cast(&Dest->front())) { + assert(PN->getNumIncomingValues() == 1 && "Crit edge found!"); + // Eliminate the PHI node + PN->replaceAllUsesWith(PN->getIncomingValue(0)); + Dest->getInstList().erase(PN); + } + + // If there are values defined in the "OldSucc" basic block, we need to insert + // PHI nodes in the regions we are dealing with to emulate them. This can + // insert dead phi nodes, but it is more trouble to see if they are used than + // to just blindly insert them. + // + if (EF->dominates(OldSucc, Dest)) { + // RegionExitBlocks - Find all of the blocks that are not dominated by Dest, + // but have predecessors that are. Additionally, prune down the set to only + // include blocks that are dominated by OldSucc as well. + // + std::vector RegionExitBlocks; + CalculateRegionExitBlocks(Dest, OldSucc, RegionExitBlocks); + + for (BasicBlock::iterator I = OldSucc->begin(), E = OldSucc->end(); + I != E; ++I) + if (I->getType() != Type::VoidTy) { + // Create and insert the PHI node into the top of Dest. + PHINode *NewPN = new PHINode(I->getType(), I->getName()+".fw_merge", + Dest->begin()); + // There is definitely an edge from OldSucc... add the edge now + NewPN->addIncoming(I, OldSucc); + + // There is also an edge from BB now, add the edge with the calculated + // value from the RI. + NewPN->addIncoming(getReplacementOrValue(I, RI), BB); + + // Make everything in the Dest region use the new PHI node now... + ReplaceUsesOfValueInRegion(I, NewPN, Dest); + + // Make sure that exits out of the region dominated by NewPN get PHI + // nodes that merge the values as appropriate. + InsertRegionExitMerges(NewPN, I, RegionExitBlocks); + } + } + + // If there were PHI nodes in OldSucc, we need to remove the entry for this + // edge from the PHI node, and we need to replace any references to the PHI + // node with a new value. + // + for (BasicBlock::iterator I = OldSucc->begin(); isa(I); ) { + PHINode *PN = cast(I); + + // Get the value flowing across the old edge and remove the PHI node entry + // for this edge: we are about to remove the edge! Don't remove the PHI + // node yet though if this is the last edge into it. + Value *EdgeValue = PN->removeIncomingValue(BB, false); + + // Make sure that anything that used to use PN now refers to EdgeValue + ReplaceUsesOfValueInRegion(PN, EdgeValue, Dest); + + // If there is only one value left coming into the PHI node, replace the PHI + // node itself with the one incoming value left. + // + if (PN->getNumIncomingValues() == 1) { + assert(PN->getNumIncomingValues() == 1); + PN->replaceAllUsesWith(PN->getIncomingValue(0)); + PN->getParent()->getInstList().erase(PN); + I = OldSucc->begin(); + } else if (PN->getNumIncomingValues() == 0) { // Nuke the PHI + // If we removed the last incoming value to this PHI, nuke the PHI node + // now. + PN->replaceAllUsesWith(Constant::getNullValue(PN->getType())); + PN->getParent()->getInstList().erase(PN); + I = OldSucc->begin(); + } else { + ++I; // Otherwise, move on to the next PHI node + } + } + + // Actually revector the branch now... + TI->setSuccessor(SuccNo, Dest); + + // If we just introduced a critical edge in the flow graph, make sure to break + // it right away... + SplitCriticalEdge(TI, SuccNo, this); + + // Make sure that we don't introduce critical edges from oldsucc now! + for (unsigned i = 0, e = OldSucc->getTerminator()->getNumSuccessors(); + i != e; ++i) + SplitCriticalEdge(OldSucc->getTerminator(), i, this); + + // Since we invalidated the CFG, recalculate the dominator set so that it is + // useful for later processing! + // FIXME: This is much worse than it really should be! + //EF->recalculate(); + + DOUT << "After forwarding: " << *BB->getParent(); +} + +/// ReplaceUsesOfValueInRegion - This method replaces all uses of Orig with uses +/// of New. It only affects instructions that are defined in basic blocks that +/// are dominated by Head. +/// +void CEE::ReplaceUsesOfValueInRegion(Value *Orig, Value *New, + BasicBlock *RegionDominator) { + assert(Orig != New && "Cannot replace value with itself"); + std::vector InstsToChange; + std::vector PHIsToChange; + InstsToChange.reserve(Orig->getNumUses()); + + // Loop over instructions adding them to InstsToChange vector, this allows us + // an easy way to avoid invalidating the use_iterator at a bad time. + for (Value::use_iterator I = Orig->use_begin(), E = Orig->use_end(); + I != E; ++I) + if (Instruction *User = dyn_cast(*I)) + if (EF->dominates(RegionDominator, User->getParent())) + InstsToChange.push_back(User); + else if (PHINode *PN = dyn_cast(User)) { + PHIsToChange.push_back(PN); + } + + // PHIsToChange contains PHI nodes that use Orig that do not live in blocks + // dominated by orig. If the block the value flows in from is dominated by + // RegionDominator, then we rewrite the PHI + for (unsigned i = 0, e = PHIsToChange.size(); i != e; ++i) { + PHINode *PN = PHIsToChange[i]; + for (unsigned j = 0, e = PN->getNumIncomingValues(); j != e; ++j) + if (PN->getIncomingValue(j) == Orig && + EF->dominates(RegionDominator, PN->getIncomingBlock(j))) + PN->setIncomingValue(j, New); + } + + // Loop over the InstsToChange list, replacing all uses of Orig with uses of + // New. This list contains all of the instructions in our region that use + // Orig. + for (unsigned i = 0, e = InstsToChange.size(); i != e; ++i) + if (PHINode *PN = dyn_cast(InstsToChange[i])) { + // PHINodes must be handled carefully. If the PHI node itself is in the + // region, we have to make sure to only do the replacement for incoming + // values that correspond to basic blocks in the region. + for (unsigned j = 0, e = PN->getNumIncomingValues(); j != e; ++j) + if (PN->getIncomingValue(j) == Orig && + EF->dominates(RegionDominator, PN->getIncomingBlock(j))) + PN->setIncomingValue(j, New); + + } else { + InstsToChange[i]->replaceUsesOfWith(Orig, New); + } +} + +static void CalcRegionExitBlocks(BasicBlock *Header, BasicBlock *BB, + std::set &Visited, + ETForest &EF, + std::vector &RegionExitBlocks) { + if (Visited.count(BB)) return; + Visited.insert(BB); + + if (EF.dominates(Header, BB)) { // Block in the region, recursively traverse + for (succ_iterator I = succ_begin(BB), E = succ_end(BB); I != E; ++I) + CalcRegionExitBlocks(Header, *I, Visited, EF, RegionExitBlocks); + } else { + // Header does not dominate this block, but we have a predecessor that does + // dominate us. Add ourself to the list. + RegionExitBlocks.push_back(BB); + } +} + +/// CalculateRegionExitBlocks - Find all of the blocks that are not dominated by +/// BB, but have predecessors that are. Additionally, prune down the set to +/// only include blocks that are dominated by OldSucc as well. +/// +void CEE::CalculateRegionExitBlocks(BasicBlock *BB, BasicBlock *OldSucc, + std::vector &RegionExitBlocks){ + std::set Visited; // Don't infinite loop + + // Recursively calculate blocks we are interested in... + CalcRegionExitBlocks(BB, BB, Visited, *EF, RegionExitBlocks); + + // Filter out blocks that are not dominated by OldSucc... + for (unsigned i = 0; i != RegionExitBlocks.size(); ) { + if (EF->dominates(OldSucc, RegionExitBlocks[i])) + ++i; // Block is ok, keep it. + else { + // Move to end of list... + std::swap(RegionExitBlocks[i], RegionExitBlocks.back()); + RegionExitBlocks.pop_back(); // Nuke the end } - return 0; + } } +void CEE::InsertRegionExitMerges(PHINode *BBVal, Instruction *OldVal, + const std::vector &RegionExitBlocks) { + assert(BBVal->getType() == OldVal->getType() && "Should be derived values!"); + BasicBlock *BB = BBVal->getParent(); + + // Loop over all of the blocks we have to place PHIs in, doing it. + for (unsigned i = 0, e = RegionExitBlocks.size(); i != e; ++i) { + BasicBlock *FBlock = RegionExitBlocks[i]; // Block on the frontier + + // Create the new PHI node + PHINode *NewPN = new PHINode(BBVal->getType(), + OldVal->getName()+".fw_frontier", + FBlock->begin()); + + // Add an incoming value for every predecessor of the block... + for (pred_iterator PI = pred_begin(FBlock), PE = pred_end(FBlock); + PI != PE; ++PI) { + // If the incoming edge is from the region dominated by BB, use BBVal, + // otherwise use OldVal. + NewPN->addIncoming(EF->dominates(BB, *PI) ? BBVal : OldVal, *PI); + } + + // Now make everyone dominated by this block use this new value! + ReplaceUsesOfValueInRegion(OldVal, NewPN, FBlock); + } +} + + + // BuildRankMap - This method builds the rank map data structure which gives // each instruction/value in the function a value based on how early it appears // in the function. We give constants and globals rank 0, arguments are @@ -404,7 +758,7 @@ void CEE::BuildRankMap(Function &F) { unsigned Rank = 1; // Skip rank zero. // Number the arguments... - for (Function::aiterator I = F.abegin(), E = F.aend(); I != E; ++I) + for (Function::arg_iterator I = F.arg_begin(), E = F.arg_end(); I != E; ++I) RankMap[I] = Rank++; // Number the instructions in reverse post order... @@ -418,33 +772,46 @@ void CEE::BuildRankMap(Function &F) { } -// PropogateBranchInfo - When this method is invoked, we need to propogate +// PropagateBranchInfo - When this method is invoked, we need to propagate // information derived from the branch condition into the true and false // branches of BI. Since we know that there aren't any critical edges in the // flow graph, this can proceed unconditionally. // -void CEE::PropogateBranchInfo(BranchInst *BI) { +void CEE::PropagateBranchInfo(BranchInst *BI) { assert(BI->isConditional() && "Must be a conditional branch!"); - BasicBlock *BB = BI->getParent(); - BasicBlock *TrueBB = BI->getSuccessor(0); - BasicBlock *FalseBB = BI->getSuccessor(1); - // Propogate information into the true block... + // Propagate information into the true block... + // + PropagateEquality(BI->getCondition(), ConstantBool::getTrue(), + getRegionInfo(BI->getSuccessor(0))); + + // Propagate information into the false block... // - PropogateEquality(BI->getCondition(), ConstantBool::True, - getRegionInfo(TrueBB)); - - // Propogate information into the false block... + PropagateEquality(BI->getCondition(), ConstantBool::getFalse(), + getRegionInfo(BI->getSuccessor(1))); +} + + +// PropagateSwitchInfo - We need to propagate the value tested by the +// switch statement through each case block. +// +void CEE::PropagateSwitchInfo(SwitchInst *SI) { + // Propagate information down each of our non-default case labels. We + // don't yet propagate information down the default label, because a + // potentially large number of inequality constraints provide less + // benefit per unit work than a single equality constraint. // - PropogateEquality(BI->getCondition(), ConstantBool::False, - getRegionInfo(FalseBB)); + Value *cond = SI->getCondition(); + for (unsigned i = 1; i < SI->getNumSuccessors(); ++i) + PropagateEquality(cond, SI->getSuccessorValue(i), + getRegionInfo(SI->getSuccessor(i))); } -// PropogateEquality - If we discover that two values are equal to each other in -// a specified region, propogate this knowledge recursively. +// PropagateEquality - If we discover that two values are equal to each other in +// a specified region, propagate this knowledge recursively. // -void CEE::PropogateEquality(Value *Op0, Value *Op1, RegionInfo &RI) { +void CEE::PropagateEquality(Value *Op0, Value *Op1, RegionInfo &RI) { if (Op0 == Op1) return; // Gee whiz. Are these really equal each other? if (isa(Op0)) // Make sure the constant is always Op1 @@ -457,7 +824,8 @@ void CEE::PropogateEquality(Value *Op0, Value *Op1, RegionInfo &RI) { Relation &KnownRelation = VI.getRelation(Op1); // If we already know they're equal, don't reprocess... - if (KnownRelation.getRelation() == Instruction::SetEQ) + if (KnownRelation.getRelation() == FCmpInst::FCMP_OEQ || + KnownRelation.getRelation() == ICmpInst::ICMP_EQ) return; // If this is boolean, check to see if one of the operands is a constant. If @@ -472,66 +840,89 @@ void CEE::PropogateEquality(Value *Op0, Value *Op1, RegionInfo &RI) { // as well. // if (CB->getValue() && Inst->getOpcode() == Instruction::And) { - PropogateEquality(Inst->getOperand(0), CB, RI); - PropogateEquality(Inst->getOperand(1), CB, RI); + PropagateEquality(Inst->getOperand(0), CB, RI); + PropagateEquality(Inst->getOperand(1), CB, RI); } - + // If we know that this instruction is an OR instruction, and the result // is false, this means that both operands to the OR are know to be false // as well. // if (!CB->getValue() && Inst->getOpcode() == Instruction::Or) { - PropogateEquality(Inst->getOperand(0), CB, RI); - PropogateEquality(Inst->getOperand(1), CB, RI); + PropagateEquality(Inst->getOperand(0), CB, RI); + PropagateEquality(Inst->getOperand(1), CB, RI); } - + // If we know that this instruction is a NOT instruction, we know that the // operand is known to be the inverse of whatever the current value is. // if (BinaryOperator *BOp = dyn_cast(Inst)) if (BinaryOperator::isNot(BOp)) - PropogateEquality(BinaryOperator::getNotArgument(BOp), + PropagateEquality(BinaryOperator::getNotArgument(BOp), ConstantBool::get(!CB->getValue()), RI); - // If we know the value of a SetCC instruction, propogate the information + // If we know the value of a FCmp instruction, propagate the information // about the relation into this region as well. // - if (SetCondInst *SCI = dyn_cast(Inst)) { + if (FCmpInst *FCI = dyn_cast(Inst)) { if (CB->getValue()) { // If we know the condition is true... - // Propogate info about the LHS to the RHS & RHS to LHS - PropogateRelation(SCI->getOpcode(), SCI->getOperand(0), - SCI->getOperand(1), RI); - PropogateRelation(SCI->getSwappedCondition(), - SCI->getOperand(1), SCI->getOperand(0), RI); + // Propagate info about the LHS to the RHS & RHS to LHS + PropagateRelation(FCI->getPredicate(), FCI->getOperand(0), + FCI->getOperand(1), RI); + PropagateRelation(FCI->getSwappedPredicate(), + FCI->getOperand(1), FCI->getOperand(0), RI); } else { // If we know the condition is false... // We know the opposite of the condition is true... - Instruction::BinaryOps C = SCI->getInverseCondition(); - - PropogateRelation(C, SCI->getOperand(0), SCI->getOperand(1), RI); - PropogateRelation(SetCondInst::getSwappedCondition(C), - SCI->getOperand(1), SCI->getOperand(0), RI); + FCmpInst::Predicate C = FCI->getInversePredicate(); + + PropagateRelation(C, FCI->getOperand(0), FCI->getOperand(1), RI); + PropagateRelation(FCmpInst::getSwappedPredicate(C), + FCI->getOperand(1), FCI->getOperand(0), RI); + } + } + + // If we know the value of a ICmp instruction, propagate the information + // about the relation into this region as well. + // + if (ICmpInst *ICI = dyn_cast(Inst)) { + if (CB->getValue()) { // If we know the condition is true... + // Propagate info about the LHS to the RHS & RHS to LHS + PropagateRelation(ICI->getPredicate(), ICI->getOperand(0), + ICI->getOperand(1), RI); + PropagateRelation(ICI->getSwappedPredicate(), ICI->getOperand(1), + ICI->getOperand(1), RI); + + } else { // If we know the condition is false ... + // We know the opposite of the condition is true... + ICmpInst::Predicate C = ICI->getInversePredicate(); + + PropagateRelation(C, ICI->getOperand(0), ICI->getOperand(1), RI); + PropagateRelation(ICmpInst::getSwappedPredicate(C), + ICI->getOperand(1), ICI->getOperand(0), RI); } } } } - // Propogate information about Op0 to Op1 & visa versa - PropogateRelation(Instruction::SetEQ, Op0, Op1, RI); - PropogateRelation(Instruction::SetEQ, Op1, Op0, RI); + // Propagate information about Op0 to Op1 & visa versa + PropagateRelation(ICmpInst::ICMP_EQ, Op0, Op1, RI); + PropagateRelation(ICmpInst::ICMP_EQ, Op1, Op0, RI); + PropagateRelation(FCmpInst::FCMP_OEQ, Op0, Op1, RI); + PropagateRelation(FCmpInst::FCMP_OEQ, Op1, Op0, RI); } -// PropogateRelation - We know that the specified relation is true in all of the -// blocks in the specified region. Propogate the information about Op0 and +// PropagateRelation - We know that the specified relation is true in all of the +// blocks in the specified region. Propagate the information about Op0 and // anything derived from it into this region. // -void CEE::PropogateRelation(Instruction::BinaryOps Opcode, Value *Op0, +void CEE::PropagateRelation(unsigned Opcode, Value *Op0, Value *Op1, RegionInfo &RI) { assert(Op0->getType() == Op1->getType() && "Equal types expected!"); // Constants are already pretty well understood. We will apply information - // about the constant to Op1 in another call to PropogateRelation. + // about the constant to Op1 in another call to PropagateRelation. // if (isa(Op0)) return; @@ -546,18 +937,21 @@ void CEE::PropogateRelation(Instruction::BinaryOps Opcode, Value *Op0, return; // If we already have information that contradicts the current information we - // are propogating, ignore this info. Something bad must have happened! + // are propagating, ignore this info. Something bad must have happened! // if (Op1R.contradicts(Opcode, VI)) { Op1R.contradicts(Opcode, VI); - std::cerr << "Contradiction found for opcode: " - << Instruction::getOpcodeName(Opcode) << "\n"; - Op1R.print(std::cerr); + cerr << "Contradiction found for opcode: " + << ((isa(Op0)||isa(Op1)) ? + Instruction::getOpcodeName(Instruction::ICmp) : + Instruction::getOpcodeName(Opcode)) + << "\n"; + Op1R.print(*cerr.stream()); return; } - // If the information propogted is new, then we want process the uses of this - // instruction to propogate the information down to them. + // If the information propagated is new, then we want process the uses of this + // instruction to propagate the information down to them. // if (Op1R.incorporate(Opcode, VI)) UpdateUsersOfValue(Op0, RI); @@ -565,16 +959,16 @@ void CEE::PropogateRelation(Instruction::BinaryOps Opcode, Value *Op0, // UpdateUsersOfValue - The information about V in this region has been updated. -// Propogate this to all consumers of the value. +// Propagate this to all consumers of the value. // void CEE::UpdateUsersOfValue(Value *V, RegionInfo &RI) { for (Value::use_iterator I = V->use_begin(), E = V->use_end(); I != E; ++I) if (Instruction *Inst = dyn_cast(*I)) { // If this is an instruction using a value that we know something about, - // try to propogate information to the value produced by the + // try to propagate information to the value produced by the // instruction. We can only do this if it is an instruction we can - // propogate information for (a setcc for example), and we only WANT to + // propagate information for (a setcc for example), and we only WANT to // do this if the instruction dominates this region. // // If the instruction doesn't dominate this region, then it cannot be @@ -584,7 +978,7 @@ void CEE::UpdateUsersOfValue(Value *V, RegionInfo &RI) { // here. This check is also effectively checking to make sure that Inst // is in the same function as our region (in case V is a global f.e.). // - if (DS->properlyDominates(Inst->getParent(), RI.getEntryBlock())) + if (EF->properlyDominates(Inst->getParent(), RI.getEntryBlock())) IncorporateInstruction(Inst, RI); } } @@ -594,12 +988,11 @@ void CEE::UpdateUsersOfValue(Value *V, RegionInfo &RI) { // value produced by this instruction // void CEE::IncorporateInstruction(Instruction *Inst, RegionInfo &RI) { - if (SetCondInst *SCI = dyn_cast(Inst)) { + if (CmpInst *CI = dyn_cast(Inst)) { // See if we can figure out a result for this instruction... - Relation::KnownResult Result = getSetCCResult(SCI, RI); + Relation::KnownResult Result = getCmpResult(CI, RI); if (Result != Relation::Unknown) { - PropogateEquality(SCI, Result ? ConstantBool::True : ConstantBool::False, - RI); + PropagateEquality(CI, ConstantBool::get(Result != 0), RI); } } } @@ -610,7 +1003,7 @@ void CEE::IncorporateInstruction(Instruction *Inst, RegionInfo &RI) { // X and a constant C, we can replace all uses of X with C in the region we are // interested in. We generalize this replacement to replace variables with // other variables if they are equal and there is a variable with lower rank -// than the current one. This offers a cannonicalizing property that exposes +// than the current one. This offers a canonicalizing property that exposes // more redundancies for later transformations to take advantage of. // void CEE::ComputeReplacements(RegionInfo &RI) { @@ -633,7 +1026,14 @@ void CEE::ComputeReplacements(RegionInfo &RI) { // Loop over the relationships known about Op0. const std::vector &Relationships = VI.getRelationships(); for (unsigned i = 0, e = Relationships.size(); i != e; ++i) - if (Relationships[i].getRelation() == Instruction::SetEQ) { + if (Relationships[i].getRelation() == FCmpInst::FCMP_OEQ) { + unsigned R = getRank(Relationships[i].getValue()); + if (R < MinRank) { + MinRank = R; + Replacement = Relationships[i].getValue(); + } + } + else if (Relationships[i].getRelation() == ICmpInst::ICMP_EQ) { unsigned R = getRank(Relationships[i].getValue()); if (R < MinRank) { MinRank = R; @@ -654,22 +1054,22 @@ void CEE::ComputeReplacements(RegionInfo &RI) { bool CEE::SimplifyBasicBlock(BasicBlock &BB, const RegionInfo &RI) { bool Changed = false; for (BasicBlock::iterator I = BB.begin(), E = BB.end(); I != E; ) { - Instruction *Inst = &*I++; + Instruction *Inst = I++; // Convert instruction arguments to canonical forms... Changed |= SimplifyInstruction(Inst, RI); - if (SetCondInst *SCI = dyn_cast(Inst)) { + if (CmpInst *CI = dyn_cast(Inst)) { // Try to simplify a setcc instruction based on inherited information - Relation::KnownResult Result = getSetCCResult(SCI, RI); + Relation::KnownResult Result = getCmpResult(CI, RI); if (Result != Relation::Unknown) { - DEBUG(std::cerr << "Replacing setcc with " << Result - << " constant: " << SCI); + DEBUG(cerr << "Replacing icmp with " << Result + << " constant: " << *CI); - SCI->replaceAllUsesWith(ConstantBool::get((bool)Result)); + CI->replaceAllUsesWith(ConstantBool::get((bool)Result)); // The instruction is now dead, remove it from the program. - SCI->getParent()->getInstList().erase(SCI); - ++NumSetCCRemoved; + CI->getParent()->getInstList().erase(CI); + ++NumCmpRemoved; Changed = true; } } @@ -679,7 +1079,7 @@ bool CEE::SimplifyBasicBlock(BasicBlock &BB, const RegionInfo &RI) { } // SimplifyInstruction - Inspect the operands of the instruction, converting -// them to their cannonical form if possible. This takes care of, for example, +// them to their canonical form if possible. This takes care of, for example, // replacing a value 'X' with a constant 'C' if the instruction in question is // dominated by a true seteq 'X', 'C'. // @@ -691,8 +1091,8 @@ bool CEE::SimplifyInstruction(Instruction *I, const RegionInfo &RI) { if (Value *Repl = VI->getReplacement()) { // If we know if a replacement with lower rank than Op0, make the // replacement now. - DEBUG(std::cerr << "In Inst: " << I << " Replacing operand #" << i - << " with " << Repl << "\n"); + DOUT << "In Inst: " << *I << " Replacing operand #" << i + << " with " << *Repl << "\n"; I->setOperand(i, Repl); Changed = true; ++NumOperandsCann; @@ -701,33 +1101,35 @@ bool CEE::SimplifyInstruction(Instruction *I, const RegionInfo &RI) { return Changed; } - -// SimplifySetCC - Try to simplify a setcc instruction based on information -// inherited from a dominating setcc instruction. V is one of the operands to -// the setcc instruction, and VI is the set of information known about it. We +// getCmpResult - Try to simplify a cmp instruction based on information +// inherited from a dominating icmp instruction. V is one of the operands to +// the icmp instruction, and VI is the set of information known about it. We // take two cases into consideration here. If the comparison is against a // constant value, we can use the constant range to see if the comparison is // possible to succeed. If it is not a comparison against a constant, we check // to see if there is a known relationship between the two values. If so, we // may be able to eliminate the check. // -Relation::KnownResult CEE::getSetCCResult(SetCondInst *SCI, - const RegionInfo &RI) { - Value *Op0 = SCI->getOperand(0), *Op1 = SCI->getOperand(1); - Instruction::BinaryOps Opcode = SCI->getOpcode(); - +Relation::KnownResult CEE::getCmpResult(CmpInst *CI, + const RegionInfo &RI) { + Value *Op0 = CI->getOperand(0), *Op1 = CI->getOperand(1); + unsigned short predicate = CI->getPredicate(); + if (isa(Op0)) { if (isa(Op1)) { - if (Constant *Result = ConstantFoldInstruction(SCI)) { - // Wow, this is easy, directly eliminate the SetCondInst. - DEBUG(std::cerr << "Replacing setcc with constant fold: " << SCI); + if (Constant *Result = ConstantFoldInstruction(CI)) { + // Wow, this is easy, directly eliminate the ICmpInst. + DEBUG(cerr << "Replacing cmp with constant fold: " << *CI); return cast(Result)->getValue() ? Relation::KnownTrue : Relation::KnownFalse; } } else { // We want to swap this instruction so that operand #0 is the constant. std::swap(Op0, Op1); - Opcode = SCI->getSwappedCondition(); + if (isa(CI)) + predicate = cast(CI)->getSwappedPredicate(); + else + predicate = cast(CI)->getSwappedPredicate(); } } @@ -739,16 +1141,17 @@ Relation::KnownResult CEE::getSetCCResult(SetCondInst *SCI, // At this point, we know that if we have a constant argument that it is in // Op1. Check to see if we know anything about comparing value with a - // constant, and if we can use this info to fold the setcc. + // constant, and if we can use this info to fold the icmp. // if (ConstantIntegral *C = dyn_cast(Op1)) { // Check to see if we already know the result of this comparison... - ConstantRange R = ConstantRange(Opcode, C); - ConstantRange Int = R.intersectWith(Op0VI->getBounds()); + ConstantRange R = ConstantRange(predicate, C); + ConstantRange Int = R.intersectWith(Op0VI->getBounds(), + ICmpInst::isSignedPredicate(ICmpInst::Predicate(predicate))); // If the intersection of the two ranges is empty, then the condition // could never be true! - // + // if (Int.isEmptySet()) { Result = Relation::KnownFalse; @@ -766,7 +1169,7 @@ Relation::KnownResult CEE::getSetCCResult(SetCondInst *SCI, // // Do we have value information about Op0 and a relation to Op1? if (const Relation *Op2R = Op0VI->requestRelation(Op1)) - Result = Op2R->getImpliedResult(Opcode); + Result = Op2R->getImpliedResult(predicate); } } return Result; @@ -776,33 +1179,10 @@ Relation::KnownResult CEE::getSetCCResult(SetCondInst *SCI, // Relation Implementation //===----------------------------------------------------------------------===// -// CheckCondition - Return true if the specified condition is false. Bound may -// be null. -static bool CheckCondition(Constant *Bound, Constant *C, - Instruction::BinaryOps BO) { - assert(C != 0 && "C is not specified!"); - if (Bound == 0) return false; - - ConstantBool *Val; - switch (BO) { - default: assert(0 && "Unknown Condition code!"); - case Instruction::SetEQ: Val = *Bound == *C; break; - case Instruction::SetNE: Val = *Bound != *C; break; - case Instruction::SetLT: Val = *Bound < *C; break; - case Instruction::SetGT: Val = *Bound > *C; break; - case Instruction::SetLE: Val = *Bound <= *C; break; - case Instruction::SetGE: Val = *Bound >= *C; break; - } - - // ConstantHandling code may not succeed in the comparison... - if (Val == 0) return false; - return !Val->getValue(); // Return true if the condition is false... -} - // contradicts - Return true if the relationship specified by the operand // contradicts already known information. // -bool Relation::contradicts(Instruction::BinaryOps Op, +bool Relation::contradicts(unsigned Op, const ValueInfo &VI) const { assert (Op != Instruction::Add && "Invalid relation argument!"); @@ -810,24 +1190,48 @@ bool Relation::contradicts(Instruction::BinaryOps Op, // does not contradict properties known about the bounds of the constant. // if (ConstantIntegral *C = dyn_cast(Val)) - if (ConstantRange(Op, C).intersectWith(VI.getBounds()).isEmptySet()) - return true; + if (Op >= ICmpInst::FIRST_ICMP_PREDICATE && + Op <= ICmpInst::LAST_ICMP_PREDICATE) + if (ConstantRange(Op, C).intersectWith(VI.getBounds(), + ICmpInst::isSignedPredicate(ICmpInst::Predicate(Op))).isEmptySet()) + return true; switch (Rel) { default: assert(0 && "Unknown Relationship code!"); case Instruction::Add: return false; // Nothing known, nothing contradicts - case Instruction::SetEQ: - return Op == Instruction::SetLT || Op == Instruction::SetGT || - Op == Instruction::SetNE; - case Instruction::SetNE: return Op == Instruction::SetEQ; - case Instruction::SetLE: return Op == Instruction::SetGT; - case Instruction::SetGE: return Op == Instruction::SetLT; - case Instruction::SetLT: - return Op == Instruction::SetEQ || Op == Instruction::SetGT || - Op == Instruction::SetGE; - case Instruction::SetGT: - return Op == Instruction::SetEQ || Op == Instruction::SetLT || - Op == Instruction::SetLE; + case ICmpInst::ICMP_EQ: + return Op == ICmpInst::ICMP_ULT || Op == ICmpInst::ICMP_SLT || + Op == ICmpInst::ICMP_UGT || Op == ICmpInst::ICMP_SGT || + Op == ICmpInst::ICMP_NE; + case ICmpInst::ICMP_NE: return Op == ICmpInst::ICMP_EQ; + case ICmpInst::ICMP_ULE: + case ICmpInst::ICMP_SLE: return Op == ICmpInst::ICMP_UGT || + Op == ICmpInst::ICMP_SGT; + case ICmpInst::ICMP_UGE: + case ICmpInst::ICMP_SGE: return Op == ICmpInst::ICMP_ULT || + Op == ICmpInst::ICMP_SLT; + case ICmpInst::ICMP_ULT: + case ICmpInst::ICMP_SLT: + return Op == ICmpInst::ICMP_EQ || Op == ICmpInst::ICMP_UGT || + Op == ICmpInst::ICMP_SGT || Op == ICmpInst::ICMP_UGE || + Op == ICmpInst::ICMP_SGE; + case ICmpInst::ICMP_UGT: + case ICmpInst::ICMP_SGT: + return Op == ICmpInst::ICMP_EQ || Op == ICmpInst::ICMP_ULT || + Op == ICmpInst::ICMP_SLT || Op == ICmpInst::ICMP_ULE || + Op == ICmpInst::ICMP_SLE; + case FCmpInst::FCMP_OEQ: + return Op == FCmpInst::FCMP_OLT || Op == FCmpInst::FCMP_OGT || + Op == FCmpInst::FCMP_ONE; + case FCmpInst::FCMP_ONE: return Op == FCmpInst::FCMP_OEQ; + case FCmpInst::FCMP_OLE: return Op == FCmpInst::FCMP_OGT; + case FCmpInst::FCMP_OGE: return Op == FCmpInst::FCMP_OLT; + case FCmpInst::FCMP_OLT: + return Op == FCmpInst::FCMP_OEQ || Op == FCmpInst::FCMP_OGT || + Op == FCmpInst::FCMP_OGE; + case FCmpInst::FCMP_OGT: + return Op == FCmpInst::FCMP_OEQ || Op == FCmpInst::FCMP_OLT || + Op == FCmpInst::FCMP_OLE; } } @@ -836,7 +1240,7 @@ bool Relation::contradicts(Instruction::BinaryOps Op, // new information is gained, true is returned, otherwise false is returned to // indicate that nothing was updated. // -bool Relation::incorporate(Instruction::BinaryOps Op, ValueInfo &VI) { +bool Relation::incorporate(unsigned Op, ValueInfo &VI) { assert(!contradicts(Op, VI) && "Cannot incorporate contradictory information!"); @@ -844,30 +1248,64 @@ bool Relation::incorporate(Instruction::BinaryOps Op, ValueInfo &VI) { // range that is possible for the value to have... // if (ConstantIntegral *C = dyn_cast(Val)) - VI.getBounds() = ConstantRange(Op, C).intersectWith(VI.getBounds()); + if (Op >= ICmpInst::FIRST_ICMP_PREDICATE && + Op <= ICmpInst::LAST_ICMP_PREDICATE) + VI.getBounds() = ConstantRange(Op, C).intersectWith(VI.getBounds(), + ICmpInst::isSignedPredicate(ICmpInst::Predicate(Op))); switch (Rel) { default: assert(0 && "Unknown prior value!"); case Instruction::Add: Rel = Op; return true; - case Instruction::SetEQ: return false; // Nothing is more precise - case Instruction::SetNE: return false; // Nothing is more precise - case Instruction::SetLT: return false; // Nothing is more precise - case Instruction::SetGT: return false; // Nothing is more precise - case Instruction::SetLE: - if (Op == Instruction::SetEQ || Op == Instruction::SetLT) { + case ICmpInst::ICMP_EQ: + case ICmpInst::ICMP_NE: + case ICmpInst::ICMP_ULT: + case ICmpInst::ICMP_SLT: + case ICmpInst::ICMP_UGT: + case ICmpInst::ICMP_SGT: return false; // Nothing is more precise + case ICmpInst::ICMP_ULE: + case ICmpInst::ICMP_SLE: + if (Op == ICmpInst::ICMP_EQ || Op == ICmpInst::ICMP_ULT || + Op == ICmpInst::ICMP_SLT) { + Rel = Op; + return true; + } else if (Op == ICmpInst::ICMP_NE) { + Rel = Rel == ICmpInst::ICMP_ULE ? ICmpInst::ICMP_ULT : + ICmpInst::ICMP_SLT; + return true; + } + return false; + case ICmpInst::ICMP_UGE: + case ICmpInst::ICMP_SGE: + if (Op == ICmpInst::ICMP_EQ || ICmpInst::ICMP_UGT || + Op == ICmpInst::ICMP_SGT) { Rel = Op; return true; - } else if (Op == Instruction::SetNE) { - Rel = Instruction::SetLT; + } else if (Op == ICmpInst::ICMP_NE) { + Rel = Rel == ICmpInst::ICMP_UGE ? ICmpInst::ICMP_UGT : + ICmpInst::ICMP_SGT; return true; } return false; - case Instruction::SetGE: return Op == Instruction::SetLT; - if (Op == Instruction::SetEQ || Op == Instruction::SetGT) { + case FCmpInst::FCMP_OEQ: return false; // Nothing is more precise + case FCmpInst::FCMP_ONE: return false; // Nothing is more precise + case FCmpInst::FCMP_OLT: return false; // Nothing is more precise + case FCmpInst::FCMP_OGT: return false; // Nothing is more precise + case FCmpInst::FCMP_OLE: + if (Op == FCmpInst::FCMP_OEQ || Op == FCmpInst::FCMP_OLT) { Rel = Op; return true; - } else if (Op == Instruction::SetNE) { - Rel = Instruction::SetGT; + } else if (Op == FCmpInst::FCMP_ONE) { + Rel = FCmpInst::FCMP_OLT; + return true; + } + return false; + case FCmpInst::FCMP_OGE: + return Op == FCmpInst::FCMP_OLT; + if (Op == FCmpInst::FCMP_OEQ || Op == FCmpInst::FCMP_OGT) { + Rel = Op; + return true; + } else if (Op == FCmpInst::FCMP_ONE) { + Rel = FCmpInst::FCMP_OGT; return true; } return false; @@ -879,28 +1317,67 @@ bool Relation::incorporate(Instruction::BinaryOps Op, ValueInfo &VI) { // determine the result required, return Unknown. // Relation::KnownResult -Relation::getImpliedResult(Instruction::BinaryOps Op) const { +Relation::getImpliedResult(unsigned Op) const { if (Rel == Op) return KnownTrue; - if (Rel == SetCondInst::getInverseCondition(Op)) return KnownFalse; + if (Op >= ICmpInst::FIRST_ICMP_PREDICATE && + Op <= ICmpInst::LAST_ICMP_PREDICATE) { + if (Rel == unsigned(ICmpInst::getInversePredicate(ICmpInst::Predicate(Op)))) + return KnownFalse; + } else if (Op <= FCmpInst::LAST_FCMP_PREDICATE) { + if (Rel == unsigned(FCmpInst::getInversePredicate(FCmpInst::Predicate(Op)))) + return KnownFalse; + } switch (Rel) { default: assert(0 && "Unknown prior value!"); - case Instruction::SetEQ: - if (Op == Instruction::SetLE || Op == Instruction::SetGE) return KnownTrue; - if (Op == Instruction::SetLT || Op == Instruction::SetGT) return KnownFalse; + case ICmpInst::ICMP_EQ: + if (Op == ICmpInst::ICMP_ULE || Op == ICmpInst::ICMP_SLE || + Op == ICmpInst::ICMP_UGE || Op == ICmpInst::ICMP_SGE) return KnownTrue; + if (Op == ICmpInst::ICMP_ULT || Op == ICmpInst::ICMP_SLT || + Op == ICmpInst::ICMP_UGT || Op == ICmpInst::ICMP_SGT) return KnownFalse; + break; + case ICmpInst::ICMP_ULT: + case ICmpInst::ICMP_SLT: + if (Op == ICmpInst::ICMP_ULE || Op == ICmpInst::ICMP_SLE || + Op == ICmpInst::ICMP_NE) return KnownTrue; + if (Op == ICmpInst::ICMP_EQ) return KnownFalse; + break; + case ICmpInst::ICMP_UGT: + case ICmpInst::ICMP_SGT: + if (Op == ICmpInst::ICMP_UGE || Op == ICmpInst::ICMP_SGE || + Op == ICmpInst::ICMP_NE) return KnownTrue; + if (Op == ICmpInst::ICMP_EQ) return KnownFalse; + break; + case FCmpInst::FCMP_OEQ: + if (Op == FCmpInst::FCMP_OLE || Op == FCmpInst::FCMP_OGE) return KnownTrue; + if (Op == FCmpInst::FCMP_OLT || Op == FCmpInst::FCMP_OGT) return KnownFalse; break; - case Instruction::SetLT: - if (Op == Instruction::SetNE || Op == Instruction::SetLE) return KnownTrue; - if (Op == Instruction::SetEQ) return KnownFalse; + case FCmpInst::FCMP_OLT: + if (Op == FCmpInst::FCMP_ONE || Op == FCmpInst::FCMP_OLE) return KnownTrue; + if (Op == FCmpInst::FCMP_OEQ) return KnownFalse; break; - case Instruction::SetGT: - if (Op == Instruction::SetNE || Op == Instruction::SetGE) return KnownTrue; - if (Op == Instruction::SetEQ) return KnownFalse; + case FCmpInst::FCMP_OGT: + if (Op == FCmpInst::FCMP_ONE || Op == FCmpInst::FCMP_OGE) return KnownTrue; + if (Op == FCmpInst::FCMP_OEQ) return KnownFalse; break; - case Instruction::SetNE: - case Instruction::SetLE: - case Instruction::SetGE: - case Instruction::Add: + case ICmpInst::ICMP_NE: + case ICmpInst::ICMP_SLE: + case ICmpInst::ICMP_ULE: + case ICmpInst::ICMP_UGE: + case ICmpInst::ICMP_SGE: + case FCmpInst::FCMP_ONE: + case FCmpInst::FCMP_OLE: + case FCmpInst::FCMP_OGE: + case FCmpInst::FCMP_FALSE: + case FCmpInst::FCMP_ORD: + case FCmpInst::FCMP_UNO: + case FCmpInst::FCMP_UEQ: + case FCmpInst::FCMP_UGT: + case FCmpInst::FCMP_UGE: + case FCmpInst::FCMP_ULT: + case FCmpInst::FCMP_ULE: + case FCmpInst::FCMP_UNE: + case FCmpInst::FCMP_TRUE: break; } return Unknown; @@ -914,7 +1391,7 @@ Relation::getImpliedResult(Instruction::BinaryOps Op) const { // print - Implement the standard print form to print out analysis information. void CEE::print(std::ostream &O, const Module *M) const { O << "\nPrinting Correlated Expression Info:\n"; - for (std::map::const_iterator I = + for (std::map::const_iterator I = RegionInfoMap.begin(), E = RegionInfoMap.end(); I != E; ++I) I->second.print(O); } @@ -953,17 +1430,37 @@ void Relation::print(std::ostream &OS) const { OS << " is "; switch (Rel) { default: OS << "*UNKNOWN*"; break; - case Instruction::SetEQ: OS << "== "; break; - case Instruction::SetNE: OS << "!= "; break; - case Instruction::SetLT: OS << "< "; break; - case Instruction::SetGT: OS << "> "; break; - case Instruction::SetLE: OS << "<= "; break; - case Instruction::SetGE: OS << ">= "; break; + case ICmpInst::ICMP_EQ: + case FCmpInst::FCMP_ORD: + case FCmpInst::FCMP_UEQ: + case FCmpInst::FCMP_OEQ: OS << "== "; break; + case ICmpInst::ICMP_NE: + case FCmpInst::FCMP_UNO: + case FCmpInst::FCMP_UNE: + case FCmpInst::FCMP_ONE: OS << "!= "; break; + case ICmpInst::ICMP_ULT: + case ICmpInst::ICMP_SLT: + case FCmpInst::FCMP_ULT: + case FCmpInst::FCMP_OLT: OS << "< "; break; + case ICmpInst::ICMP_UGT: + case ICmpInst::ICMP_SGT: + case FCmpInst::FCMP_UGT: + case FCmpInst::FCMP_OGT: OS << "> "; break; + case ICmpInst::ICMP_ULE: + case ICmpInst::ICMP_SLE: + case FCmpInst::FCMP_ULE: + case FCmpInst::FCMP_OLE: OS << "<= "; break; + case ICmpInst::ICMP_UGE: + case ICmpInst::ICMP_SGE: + case FCmpInst::FCMP_UGE: + case FCmpInst::FCMP_OGE: OS << ">= "; break; } WriteAsOperand(OS, Val); OS << "\n"; } -void Relation::dump() const { print(std::cerr); } -void ValueInfo::dump() const { print(std::cerr, 0); } +// Don't inline these methods or else we won't be able to call them from GDB! +void Relation::dump() const { print(*cerr.stream()); } +void ValueInfo::dump() const { print(*cerr.stream(), 0); } +void RegionInfo::dump() const { print(*cerr.stream()); }