From 412df08b596d1b31dcee7943d5a9424f7b9751b9 Mon Sep 17 00:00:00 2001 From: Owen Anderson Date: Sun, 4 Oct 2009 18:49:55 +0000 Subject: [PATCH] Do away with the strange use of BitVectors in SSI, and just use normal sets. This makes the code much more C++/LLVM-ish. llvm-svn: 83286 --- include/llvm/Transforms/Utils/SSI.h | 30 ++--- lib/Transforms/Utils/SSI.cpp | 192 ++++++++++++---------------- 2 files changed, 94 insertions(+), 128 deletions(-) diff --git a/include/llvm/Transforms/Utils/SSI.h b/include/llvm/Transforms/Utils/SSI.h index 8b49aac080f..ff5bb7b8614 100644 --- a/include/llvm/Transforms/Utils/SSI.h +++ b/include/llvm/Transforms/Utils/SSI.h @@ -23,7 +23,6 @@ #define LLVM_TRANSFORMS_UTILS_SSI_H #include "llvm/Pass.h" -#include "llvm/ADT/BitVector.h" #include "llvm/ADT/DenseMap.h" #include "llvm/ADT/SmallPtrSet.h" #include "llvm/ADT/SmallVector.h" @@ -55,43 +54,36 @@ namespace llvm { // Stores variables created by SSI SmallPtrSet created; - // These variables are only live for each creation - unsigned num_values; - - // Has a bit for each variable, true if it needs to be created - // and false otherwise - BitVector needConstruction; - // Phis created by SSI - DenseMap phis; + DenseMap phis; // Sigmas created by SSI - DenseMap sigmas; + DenseMap sigmas; // Phi nodes that have a phi as operand and has to be fixed SmallPtrSet phisToFix; // List of definition points for every variable - SmallVector, 0> defsites; + DenseMap > defsites; // Basic Block of the original definition of each variable - SmallVector value_original; + DenseMap value_original; // Stack of last seen definition of a variable - SmallVector, 0> value_stack; + DenseMap > value_stack; - void insertSigmaFunctions(SmallVectorImpl &value); - void insertSigma(TerminatorInst *TI, Instruction *I, unsigned pos); - void insertPhiFunctions(SmallVectorImpl &value); - void renameInit(SmallVectorImpl &value); + void insertSigmaFunctions(SmallPtrSet &value); + void insertSigma(TerminatorInst *TI, Instruction *I); + void insertPhiFunctions(SmallPtrSet &value); + void renameInit(SmallPtrSet &value); void rename(BasicBlock *BB); void substituteUse(Instruction *I); bool dominateAny(BasicBlock *BB, Instruction *value); void fixPhis(); - unsigned getPositionPhi(PHINode *PN); - unsigned getPositionSigma(PHINode *PN); + Instruction* getPositionPhi(PHINode *PN); + Instruction* getPositionSigma(PHINode *PN); void init(SmallVectorImpl &value); void clean(); diff --git a/lib/Transforms/Utils/SSI.cpp b/lib/Transforms/Utils/SSI.cpp index ef49d9624b0..3bb2e8ee691 100644 --- a/lib/Transforms/Utils/SSI.cpp +++ b/lib/Transforms/Utils/SSI.cpp @@ -31,8 +31,6 @@ using namespace llvm; static const std::string SSI_PHI = "SSI_phi"; static const std::string SSI_SIG = "SSI_sigma"; -static const unsigned UNSIGNED_INFINITE = ~0U; - STATISTIC(NumSigmaInserted, "Number of sigma functions inserted"); STATISTIC(NumPhiInserted, "Number of phi functions inserted"); @@ -54,17 +52,18 @@ bool SSI::runOnFunction(Function &F) { void SSI::createSSI(SmallVectorImpl &value) { init(value); - for (unsigned i = 0; i < num_values; ++i) { - if (created.insert(value[i])) { - needConstruction[i] = true; - } - } - insertSigmaFunctions(value); + SmallPtrSet needConstruction; + for (SmallVectorImpl::iterator I = value.begin(), + E = value.end(); I != E; ++I) + if (created.insert(*I)) + needConstruction.insert(*I); + + insertSigmaFunctions(needConstruction); // Test if there is a need to transform to SSI - if (needConstruction.any()) { - insertPhiFunctions(value); - renameInit(value); + if (!needConstruction.empty()) { + insertPhiFunctions(needConstruction); + renameInit(needConstruction); rename(DT_->getRoot()); fixPhis(); } @@ -75,21 +74,19 @@ void SSI::createSSI(SmallVectorImpl &value) { /// Insert sigma functions (a sigma function is a phi function with one /// operator) /// -void SSI::insertSigmaFunctions(SmallVectorImpl &value) { - for (unsigned i = 0; i < num_values; ++i) { - if (!needConstruction[i]) - continue; - - for (Value::use_iterator begin = value[i]->use_begin(), end = - value[i]->use_end(); begin != end; ++begin) { +void SSI::insertSigmaFunctions(SmallPtrSet &value) { + for (SmallPtrSet::iterator I = value.begin(), + E = value.end(); I != E; ++I) { + for (Value::use_iterator begin = (*I)->use_begin(), + end = (*I)->use_end(); begin != end; ++begin) { // Test if the Use of the Value is in a comparator if (CmpInst *CI = dyn_cast(begin)) { // Iterates through all uses of CmpInst - for (Value::use_iterator begin_ci = CI->use_begin(), end_ci = - CI->use_end(); begin_ci != end_ci; ++begin_ci) { + for (Value::use_iterator begin_ci = CI->use_begin(), + end_ci = CI->use_end(); begin_ci != end_ci; ++begin_ci) { // Test if any use of CmpInst is in a Terminator if (TerminatorInst *TI = dyn_cast(begin_ci)) { - insertSigma(TI, value[i], i); + insertSigma(TI, *I); } } } @@ -100,7 +97,7 @@ void SSI::insertSigmaFunctions(SmallVectorImpl &value) { /// Inserts Sigma Functions in every BasicBlock successor to Terminator /// Instruction TI. All inserted Sigma Function are related to Instruction I. /// -void SSI::insertSigma(TerminatorInst *TI, Instruction *I, unsigned pos) { +void SSI::insertSigma(TerminatorInst *TI, Instruction *I) { // Basic Block of the Terminator Instruction BasicBlock *BB = TI->getParent(); for (unsigned i = 0, e = TI->getNumSuccessors(); i < e; ++i) { @@ -111,10 +108,9 @@ void SSI::insertSigma(TerminatorInst *TI, Instruction *I, unsigned pos) { dominateAny(BB_next, I)) { PHINode *PN = PHINode::Create(I->getType(), SSI_SIG, BB_next->begin()); PN->addIncoming(I, BB); - sigmas.insert(std::make_pair(PN, pos)); + sigmas[PN] = I; created.insert(PN); - needConstruction[pos] = true; - defsites[pos].push_back(BB_next); + defsites[I].push_back(BB_next); ++NumSigmaInserted; } } @@ -122,66 +118,63 @@ void SSI::insertSigma(TerminatorInst *TI, Instruction *I, unsigned pos) { /// Insert phi functions when necessary /// -void SSI::insertPhiFunctions(SmallVectorImpl &value) { +void SSI::insertPhiFunctions(SmallPtrSet &value) { DominanceFrontier *DF = &getAnalysis(); - for (unsigned i = 0; i < num_values; ++i) { + for (SmallPtrSet::iterator I = value.begin(), + E = value.end(); I != E; ++I) { // Test if there were any sigmas for this variable - if (needConstruction[i]) { + SmallPtrSet BB_visited; - SmallPtrSet BB_visited; + // Insert phi functions if there is any sigma function + while (!defsites[*I].empty()) { - // Insert phi functions if there is any sigma function - while (!defsites[i].empty()) { + BasicBlock *BB = defsites[*I].back(); - BasicBlock *BB = defsites[i].back(); + defsites[*I].pop_back(); + DominanceFrontier::iterator DF_BB = DF->find(BB); - defsites[i].pop_back(); - DominanceFrontier::iterator DF_BB = DF->find(BB); + // The BB is unreachable. Skip it. + if (DF_BB == DF->end()) + continue; - // The BB is unreachable. Skip it. - if (DF_BB == DF->end()) - continue; + // Iterates through all the dominance frontier of BB + for (std::set::iterator DF_BB_begin = + DF_BB->second.begin(), DF_BB_end = DF_BB->second.end(); + DF_BB_begin != DF_BB_end; ++DF_BB_begin) { + BasicBlock *BB_dominated = *DF_BB_begin; - // Iterates through all the dominance frontier of BB - for (std::set::iterator DF_BB_begin = - DF_BB->second.begin(), DF_BB_end = DF_BB->second.end(); - DF_BB_begin != DF_BB_end; ++DF_BB_begin) { - BasicBlock *BB_dominated = *DF_BB_begin; + // Test if has not yet visited this node and if the + // original definition dominates this node + if (BB_visited.insert(BB_dominated) && + DT_->properlyDominates(value_original[*I], BB_dominated) && + dominateAny(BB_dominated, *I)) { + PHINode *PN = PHINode::Create( + (*I)->getType(), SSI_PHI, BB_dominated->begin()); + phis.insert(std::make_pair(PN, *I)); + created.insert(PN); - // Test if has not yet visited this node and if the - // original definition dominates this node - if (BB_visited.insert(BB_dominated) && - DT_->properlyDominates(value_original[i], BB_dominated) && - dominateAny(BB_dominated, value[i])) { - PHINode *PN = PHINode::Create( - value[i]->getType(), SSI_PHI, BB_dominated->begin()); - phis.insert(std::make_pair(PN, i)); - created.insert(PN); - - defsites[i].push_back(BB_dominated); - ++NumPhiInserted; - } + defsites[*I].push_back(BB_dominated); + ++NumPhiInserted; } } - BB_visited.clear(); } + BB_visited.clear(); } } /// Some initialization for the rename part /// -void SSI::renameInit(SmallVectorImpl &value) { - value_stack.resize(num_values); - for (unsigned i = 0; i < num_values; ++i) { - value_stack[i].push_back(value[i]); - } +void SSI::renameInit(SmallPtrSet &value) { + for (SmallPtrSet::iterator I = value.begin(), + E = value.end(); I != E; ++I) + value_stack[*I].push_back(*I); } /// Renames all variables in the specified BasicBlock. /// Only variables that need to be rename will be. /// void SSI::rename(BasicBlock *BB) { - BitVector *defined = new BitVector(num_values, false); + SmallPtrSet defined; // Iterate through instructions and make appropriate renaming. // For SSI_PHI (b = PHI()), store b at value_stack as a new @@ -195,19 +188,17 @@ void SSI::rename(BasicBlock *BB) { begin != end; ++begin) { Instruction *I = begin; if (PHINode *PN = dyn_cast(I)) { // Treat PHI functions - int position; + Instruction* position; // Treat SSI_PHI - if ((position = getPositionPhi(PN)) != -1) { + if ((position = getPositionPhi(PN))) { value_stack[position].push_back(PN); - (*defined)[position] = true; - } - + defined.insert(position); // Treat SSI_SIG - else if ((position = getPositionSigma(PN)) != -1) { + } else if ((position = getPositionSigma(PN))) { substituteUse(I); value_stack[position].push_back(PN); - (*defined)[position] = true; + defined.insert(position); } // Treat all other PHI functions @@ -234,8 +225,8 @@ void SSI::rename(BasicBlock *BB) { notPhi = BB_succ->getFirstNonPHI(); begin != *notPhi; ++begin) { Instruction *I = begin; PHINode *PN = dyn_cast(I); - int position; - if (PN && ((position = getPositionPhi(PN)) != -1)) { + Instruction* position; + if (PN && ((position = getPositionPhi(PN)))) { PN->addIncoming(value_stack[position].back(), BB); } } @@ -253,15 +244,9 @@ void SSI::rename(BasicBlock *BB) { // Now we remove all inserted definitions of a variable from the top of // the stack leaving the previous one as the top. - if (defined->any()) { - for (unsigned i = 0; i < num_values; ++i) { - if ((*defined)[i]) { - value_stack[i].pop_back(); - } - } - } - - delete defined; + for (SmallPtrSet::iterator DI = defined.begin(), + DE = defined.end(); DI != DE; ++DI) + value_stack[*DI].pop_back(); } /// Substitute any use in this instruction for the last definition of @@ -270,23 +255,24 @@ void SSI::rename(BasicBlock *BB) { void SSI::substituteUse(Instruction *I) { for (unsigned i = 0, e = I->getNumOperands(); i < e; ++i) { Value *operand = I->getOperand(i); - for (unsigned j = 0; j < num_values; ++j) { - if (operand == value_stack[j].front() && - I != value_stack[j].back()) { + for (DenseMap >::iterator + VI = value_stack.begin(), VE = value_stack.end(); VI != VE; ++VI) { + if (operand == VI->second.front() && + I != VI->second.back()) { PHINode *PN_I = dyn_cast(I); - PHINode *PN_vs = dyn_cast(value_stack[j].back()); + PHINode *PN_vs = dyn_cast(VI->second.back()); // If a phi created in a BasicBlock is used as an operand of another // created in the same BasicBlock, this step marks this second phi, // to fix this issue later. It cannot be fixed now, because the // operands of the first phi are not final yet. if (PN_I && PN_vs && - value_stack[j].back()->getParent() == I->getParent()) { + VI->second.back()->getParent() == I->getParent()) { phisToFix.insert(PN_I); } - I->setOperand(i, value_stack[j].back()); + I->setOperand(i, VI->second.back()); break; } } @@ -333,7 +319,7 @@ void SSI::fixPhis() { } } - for (DenseMapIterator begin = phis.begin(), + for (DenseMapIterator begin = phis.begin(), end = phis.end(); begin != end; ++begin) { PHINode *PN = begin->first; BasicBlock *BB = PN->getParent(); @@ -359,10 +345,10 @@ void SSI::fixPhis() { /// Return which variable (position on the vector of variables) this phi /// represents on the phis list. /// -unsigned SSI::getPositionPhi(PHINode *PN) { - DenseMap::iterator val = phis.find(PN); +Instruction* SSI::getPositionPhi(PHINode *PN) { + DenseMap::iterator val = phis.find(PN); if (val == phis.end()) - return UNSIGNED_INFINITE; + return 0; else return val->second; } @@ -370,10 +356,10 @@ unsigned SSI::getPositionPhi(PHINode *PN) { /// Return which variable (position on the vector of variables) this phi /// represents on the sigmas list. /// -unsigned SSI::getPositionSigma(PHINode *PN) { - DenseMap::iterator val = sigmas.find(PN); +Instruction* SSI::getPositionSigma(PHINode *PN) { + DenseMap::iterator val = sigmas.find(PN); if (val == sigmas.end()) - return UNSIGNED_INFINITE; + return 0; else return val->second; } @@ -381,27 +367,16 @@ unsigned SSI::getPositionSigma(PHINode *PN) { /// Initializes /// void SSI::init(SmallVectorImpl &value) { - num_values = value.size(); - needConstruction.resize(num_values, false); - - value_original.resize(num_values); - defsites.resize(num_values); - - for (unsigned i = 0; i < num_values; ++i) { - value_original[i] = value[i]->getParent(); - defsites[i].push_back(value_original[i]); + for (SmallVectorImpl::iterator I = value.begin(), + E = value.end(); I != E; ++I) { + value_original[*I] = (*I)->getParent(); + defsites[*I].push_back((*I)->getParent()); } } /// Clean all used resources in this creation of SSI /// void SSI::clean() { - for (unsigned i = 0; i < num_values; ++i) { - defsites[i].clear(); - if (i < value_stack.size()) - value_stack[i].clear(); - } - phis.clear(); sigmas.clear(); phisToFix.clear(); @@ -409,7 +384,6 @@ void SSI::clean() { defsites.clear(); value_stack.clear(); value_original.clear(); - needConstruction.clear(); } /// createSSIPass - The public interface to this file...