Anand Shukla | 320febb | 2002-11-03 01:45:20 +0000 | [diff] [blame] | 1 | //===-- InstLoops.cpp ---------------------------------------- ---*- C++ -*--=// |
| 2 | // Pass to instrument loops |
| 3 | // |
| 4 | // At every backedge, insert a counter for that backedge and a call function |
| 5 | //===----------------------------------------------------------------------===// |
| 6 | |
| 7 | #include "llvm/Reoptimizer/InstLoops.h" |
Anand Shukla | b3d794a | 2003-07-10 21:55:57 +0000 | [diff] [blame^] | 8 | #include "llvm/Analysis/Dominators.h" |
Anand Shukla | 320febb | 2002-11-03 01:45:20 +0000 | [diff] [blame] | 9 | #include "llvm/Support/CFG.h" |
| 10 | #include "llvm/Constants.h" |
| 11 | #include "llvm/iMemory.h" |
| 12 | #include "llvm/GlobalVariable.h" |
| 13 | #include "llvm/DerivedTypes.h" |
| 14 | #include "llvm/iOther.h" |
| 15 | #include "llvm/iOperators.h" |
| 16 | #include "llvm/iTerminators.h" |
| 17 | #include "llvm/iPHINode.h" |
| 18 | #include "llvm/Module.h" |
| 19 | #include "llvm/Function.h" |
| 20 | #include "llvm/Pass.h" |
| 21 | |
| 22 | //this is used to color vertices |
| 23 | //during DFS |
| 24 | |
| 25 | enum Color{ |
| 26 | WHITE, |
| 27 | GREY, |
| 28 | BLACK |
| 29 | }; |
| 30 | |
Anand Shukla | b3d794a | 2003-07-10 21:55:57 +0000 | [diff] [blame^] | 31 | namespace{ |
| 32 | struct InstLoops : public FunctionPass { |
| 33 | virtual void getAnalysisUsage(AnalysisUsage &AU) const { |
| 34 | AU.addRequired<DominatorSet>(); |
| 35 | } |
| 36 | private: |
| 37 | DominatorSet *DS; |
| 38 | void getBackEdgesVisit(BasicBlock *u, |
| 39 | std::map<BasicBlock *, Color > &color, |
| 40 | std::map<BasicBlock *, int > &d, |
| 41 | int &time, Value *threshold, |
| 42 | std::map<BasicBlock *, BasicBlock *> &be); |
| 43 | void removeRedundant(std::map<BasicBlock *, BasicBlock *> &be); |
| 44 | void getBackEdges(Function &F, Value *threshold); |
| 45 | public: |
| 46 | bool runOnFunction(Function &F); |
| 47 | }; |
| 48 | |
| 49 | RegisterOpt<InstLoops> X("instloops", "Instrument backedges for profiling"); |
| 50 | } |
Anand Shukla | 320febb | 2002-11-03 01:45:20 +0000 | [diff] [blame] | 51 | |
Chris Lattner | e885b1f | 2003-01-14 22:34:36 +0000 | [diff] [blame] | 52 | // createInstLoopsPass - Create a new pass to add path profiling |
Anand Shukla | 320febb | 2002-11-03 01:45:20 +0000 | [diff] [blame] | 53 | // |
| 54 | Pass *createInstLoopsPass() { |
| 55 | return new InstLoops(); |
| 56 | } |
| 57 | |
| 58 | |
| 59 | //helper function to get back edges: it is called by |
| 60 | //the "getBackEdges" function below |
Anand Shukla | b3d794a | 2003-07-10 21:55:57 +0000 | [diff] [blame^] | 61 | void InstLoops::getBackEdgesVisit(BasicBlock *u, |
Anand Shukla | 320febb | 2002-11-03 01:45:20 +0000 | [diff] [blame] | 62 | std::map<BasicBlock *, Color > &color, |
| 63 | std::map<BasicBlock *, int > &d, |
Anand Shukla | b3d794a | 2003-07-10 21:55:57 +0000 | [diff] [blame^] | 64 | int &time, Value *threshold, |
| 65 | std::map<BasicBlock *, BasicBlock *> &be) { |
Anand Shukla | 320febb | 2002-11-03 01:45:20 +0000 | [diff] [blame] | 66 | |
| 67 | color[u]=GREY; |
| 68 | time++; |
| 69 | d[u]=time; |
| 70 | |
| 71 | for(BasicBlock::succ_iterator vl = succ_begin(u), |
| 72 | ve = succ_end(u); vl != ve; ++vl){ |
| 73 | |
| 74 | BasicBlock *BB = *vl; |
| 75 | |
| 76 | if(color[BB]!=GREY && color[BB]!=BLACK){ |
Anand Shukla | b3d794a | 2003-07-10 21:55:57 +0000 | [diff] [blame^] | 77 | getBackEdgesVisit(BB, color, d, time, threshold, be); |
Anand Shukla | 320febb | 2002-11-03 01:45:20 +0000 | [diff] [blame] | 78 | } |
| 79 | |
| 80 | //now checking for d and f vals |
Anand Shukla | b3d794a | 2003-07-10 21:55:57 +0000 | [diff] [blame^] | 81 | else if(color[BB]==GREY){ |
Anand Shukla | 320febb | 2002-11-03 01:45:20 +0000 | [diff] [blame] | 82 | //so v is ancestor of u if time of u > time of v |
| 83 | if(d[u] >= d[BB]){ |
Anand Shukla | b3d794a | 2003-07-10 21:55:57 +0000 | [diff] [blame^] | 84 | //u->BB is a backedge |
| 85 | be[u] = BB; |
Anand Shukla | 320febb | 2002-11-03 01:45:20 +0000 | [diff] [blame] | 86 | } |
| 87 | } |
| 88 | } |
| 89 | color[u]=BLACK;//done with visiting the node and its neighbors |
| 90 | } |
| 91 | |
Anand Shukla | b3d794a | 2003-07-10 21:55:57 +0000 | [diff] [blame^] | 92 | //look at all BEs, and remove all BEs that are dominated by other BE's in the |
| 93 | //set |
| 94 | void InstLoops::removeRedundant(std::map<BasicBlock *, BasicBlock *> &be){ |
| 95 | std::vector<BasicBlock *> toDelete; |
| 96 | for(std::map<BasicBlock *, BasicBlock *>::iterator MI = be.begin(), |
| 97 | ME = be.end(); MI != ME; ++MI){ |
| 98 | //std::cerr<<MI->first->getName()<<"\t->\t"<<MI->second->getName()<<"\n"; |
| 99 | //std::cerr<<MI->first; |
| 100 | //std::cerr<<MI->second; |
| 101 | for(std::map<BasicBlock *, BasicBlock *>::iterator MMI = be.begin(), |
| 102 | MME = be.end(); MMI != MME; ++MMI){ |
| 103 | if(DS->properlyDominates(MI->first, MMI->first)){ |
| 104 | toDelete.push_back(MMI->first); |
| 105 | //std::cerr<<MI->first->getName()<<"\t Dominates\t"<<MMI->first->getName(); |
| 106 | } |
| 107 | } |
| 108 | } |
| 109 | |
| 110 | for(std::vector<BasicBlock *>::iterator VI = toDelete.begin(), |
| 111 | VE = toDelete.end(); VI != VE; ++VI){ |
| 112 | be.erase(*VI); |
| 113 | } |
| 114 | } |
Anand Shukla | 320febb | 2002-11-03 01:45:20 +0000 | [diff] [blame] | 115 | |
| 116 | //getting the backedges in a graph |
| 117 | //Its a variation of DFS to get the backedges in the graph |
| 118 | //We get back edges by associating a time |
| 119 | //and a color with each vertex. |
| 120 | //The time of a vertex is the time when it was first visited |
| 121 | //The color of a vertex is initially WHITE, |
| 122 | //Changes to GREY when it is first visited, |
| 123 | //and changes to BLACK when ALL its neighbors |
| 124 | //have been visited |
| 125 | //So we have a back edge when we meet a successor of |
| 126 | //a node with smaller time, and GREY color |
Anand Shukla | b3d794a | 2003-07-10 21:55:57 +0000 | [diff] [blame^] | 127 | void InstLoops::getBackEdges(Function &F, Value *threshold){ |
Anand Shukla | 320febb | 2002-11-03 01:45:20 +0000 | [diff] [blame] | 128 | std::map<BasicBlock *, Color > color; |
| 129 | std::map<BasicBlock *, int> d; |
Anand Shukla | b3d794a | 2003-07-10 21:55:57 +0000 | [diff] [blame^] | 130 | std::map<BasicBlock *, BasicBlock *> be; |
Anand Shukla | 320febb | 2002-11-03 01:45:20 +0000 | [diff] [blame] | 131 | int time=0; |
Anand Shukla | b3d794a | 2003-07-10 21:55:57 +0000 | [diff] [blame^] | 132 | getBackEdgesVisit(F.begin(), color, d, time, threshold, be); |
| 133 | |
| 134 | removeRedundant(be); |
| 135 | |
| 136 | for(std::map<BasicBlock *, BasicBlock *>::iterator MI = be.begin(), |
| 137 | ME = be.end(); MI != ME; ++MI){ |
| 138 | BasicBlock *u = MI->first; |
| 139 | BasicBlock *BB = MI->second; |
| 140 | //std::cerr<<"Edge from: "<<BB->getName()<<"->"<<u->getName()<<"\n"; |
| 141 | //insert a new basic block: modify terminator accordingly! |
| 142 | BasicBlock *newBB = new BasicBlock("", u->getParent()); |
| 143 | BranchInst *ti = cast<BranchInst>(u->getTerminator()); |
| 144 | unsigned char index = 1; |
| 145 | if(ti->getSuccessor(0) == BB){ |
| 146 | index = 0; |
| 147 | } |
| 148 | assert(ti->getNumSuccessors() > index && "Not enough successors!"); |
| 149 | ti->setSuccessor(index, newBB); |
| 150 | |
| 151 | BasicBlock::InstListType < = newBB->getInstList(); |
| 152 | |
| 153 | std::vector<const Type*> inCountArgs; |
| 154 | const FunctionType *cFty = FunctionType::get(Type::VoidTy, inCountArgs, |
| 155 | false); |
| 156 | Function *inCountMth = |
| 157 | u->getParent()->getParent()->getOrInsertFunction("llvm_first_trigger", |
| 158 | cFty); |
| 159 | |
| 160 | assert(inCountMth && "Initial method could not be inserted!"); |
| 161 | |
| 162 | Instruction *call = new CallInst(inCountMth, ""); |
| 163 | lt.push_back(call); |
| 164 | lt.push_back(new BranchInst(BB)); |
| 165 | |
| 166 | //now iterate over *vl, and set its Phi nodes right |
| 167 | for(BasicBlock::iterator BB2Inst = BB->begin(), BBend = BB->end(); |
| 168 | BB2Inst != BBend; ++BB2Inst){ |
| 169 | |
| 170 | if (PHINode *phiInst = dyn_cast<PHINode>(BB2Inst)){ |
| 171 | int bbIndex = phiInst->getBasicBlockIndex(u); |
| 172 | if(bbIndex>=0){ |
| 173 | phiInst->setIncomingBlock(bbIndex, newBB); |
| 174 | } |
| 175 | } |
| 176 | } |
| 177 | } |
Anand Shukla | 320febb | 2002-11-03 01:45:20 +0000 | [diff] [blame] | 178 | } |
| 179 | |
| 180 | //Per function pass for inserting counters and call function |
| 181 | bool InstLoops::runOnFunction(Function &F){ |
| 182 | |
| 183 | static GlobalVariable *threshold = NULL; |
| 184 | static bool insertedThreshold = false; |
Anand Shukla | 320febb | 2002-11-03 01:45:20 +0000 | [diff] [blame] | 185 | |
Anand Shukla | b3d794a | 2003-07-10 21:55:57 +0000 | [diff] [blame^] | 186 | DS = &getAnalysis<DominatorSet>(); |
| 187 | |
| 188 | if(F.isExternal()) { |
| 189 | return false; |
| 190 | } |
| 191 | |
| 192 | if(!insertedThreshold){ |
| 193 | threshold = new GlobalVariable(Type::IntTy, false, |
| 194 | GlobalValue::ExternalLinkage, 0, |
| 195 | "reopt_threshold"); |
| 196 | |
Anand Shukla | 320febb | 2002-11-03 01:45:20 +0000 | [diff] [blame] | 197 | F.getParent()->getGlobalList().push_back(threshold); |
| 198 | insertedThreshold = true; |
| 199 | } |
| 200 | |
| 201 | if(F.getName() == "main"){ |
| 202 | //intialize threshold |
| 203 | std::vector<const Type*> initialize_args; |
| 204 | initialize_args.push_back(PointerType::get(Type::IntTy)); |
| 205 | |
| 206 | const FunctionType *Fty = FunctionType::get(Type::VoidTy, initialize_args, |
| 207 | false); |
| 208 | Function *initialMeth = F.getParent()->getOrInsertFunction("reoptimizerInitialize", Fty); |
| 209 | assert(initialMeth && "Initialize method could not be inserted!"); |
| 210 | |
| 211 | std::vector<Value *> trargs; |
| 212 | trargs.push_back(threshold); |
| 213 | |
| 214 | new CallInst(initialMeth, trargs, "", F.begin()->begin()); |
| 215 | } |
| 216 | |
| 217 | assert(threshold && "GlobalVariable threshold not defined!"); |
Anand Shukla | b3d794a | 2003-07-10 21:55:57 +0000 | [diff] [blame^] | 218 | |
Anand Shukla | 320febb | 2002-11-03 01:45:20 +0000 | [diff] [blame] | 219 | getBackEdges(F, threshold); |
| 220 | |
| 221 | return true; |
| 222 | } |