-//===-- ProfilePaths.cpp - interface to insert instrumentation ---*- C++ -*--=//
+//===-- ProfilePaths.cpp - interface to insert instrumentation --*- C++ -*-===//
+//
+// 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.
+//
+//===----------------------------------------------------------------------===//
//
-// This inserts intrumentation for counting
-// execution of paths though a given function
-// Its implemented as a "Function" Pass, and called using opt
+// This inserts instrumentation for counting execution of paths though a given
+// function Its implemented as a "Function" Pass, and called using opt
//
// This pass is implemented by using algorithms similar to
// 1."Efficient Path Profiling": Ball, T. and Larus, J. R.,
-// Proceedings of Micro-29, Dec 1996, Paris, France.
+// Proceedings of Micro-29, Dec 1996, Paris, France.
// 2."Efficiently Counting Program events with support for on-line
// "queries": Ball T., ACM Transactions on Programming Languages
-// and systems, Sep 1994.
+// and systems, Sep 1994.
//
-// The algorithms work on a Graph constructed over the nodes
-// made from Basic Blocks: The transformations then take place on
-// the constucted graph (implementation in Graph.cpp and GraphAuxillary.cpp)
-// and finally, appropriate instrumentation is placed over suitable edges.
-// (code inserted through EdgeCode.cpp).
+// The algorithms work on a Graph constructed over the nodes made from Basic
+// Blocks: The transformations then take place on the constructed graph
+// (implementation in Graph.cpp and GraphAuxiliary.cpp) and finally, appropriate
+// instrumentation is placed over suitable edges. (code inserted through
+// EdgeCode.cpp).
//
-// The algorithm inserts code such that every acyclic path in the CFG
-// of a function is identified through a unique number. the code insertion
-// is optimal in the sense that its inserted over a minimal set of edges. Also,
-// the algorithm makes sure than initialization, path increment and counter
-// update can be collapsed into minmimum number of edges.
+// The algorithm inserts code such that every acyclic path in the CFG of a
+// function is identified through a unique number. the code insertion is optimal
+// in the sense that its inserted over a minimal set of edges. Also, the
+// algorithm makes sure than initialization, path increment and counter update
+// can be collapsed into minimum number of edges.
+//
//===----------------------------------------------------------------------===//
-#include "llvm/Transforms/Instrumentation/ProfilePaths.h"
-#include "llvm/Transforms/UnifyFunctionExitNodes.h"
+#include "llvm/Transforms/Utils/UnifyFunctionExitNodes.h"
#include "llvm/Support/CFG.h"
-#include "llvm/Function.h"
-#include "llvm/BasicBlock.h"
#include "llvm/Constants.h"
#include "llvm/DerivedTypes.h"
-#include "llvm/iMemory.h"
-#include "llvm/Pass.h"
+#include "llvm/Instructions.h"
+#include "llvm/Module.h"
#include "Graph.h"
+#include <fstream>
+#include <cstdio>
-using std::vector;
+namespace llvm {
struct ProfilePaths : public FunctionPass {
- const char *getPassName() const { return "ProfilePaths"; }
-
- bool runOnFunction(Function *F);
+ bool runOnFunction(Function &F);
// Before this pass, make sure that there is only one
// entry and only one exit node for the function in the CFG of the function
//
void ProfilePaths::getAnalysisUsage(AnalysisUsage &AU) const {
- AU.addRequired(UnifyFunctionExitNodes::ID);
+ AU.addRequired<UnifyFunctionExitNodes>();
}
};
-// createProfilePathsPass - Create a new pass to add path profiling
-//
-Pass *createProfilePathsPass() {
- return new ProfilePaths();
-}
-
+static RegisterOpt<ProfilePaths> X("paths", "Profile Paths");
-static Node *findBB(std::set<Node *> &st, BasicBlock *BB){
- for(std::set<Node *>::iterator si=st.begin(); si!=st.end(); ++si){
+static Node *findBB(std::vector<Node *> &st, BasicBlock *BB){
+ for(std::vector<Node *>::iterator si=st.begin(); si!=st.end(); ++si){
if(((*si)->getElement())==BB){
return *si;
}
}
//Per function pass for inserting counters and trigger code
-bool ProfilePaths::runOnFunction(Function *M){
- // Transform the cfg s.t. we have just one exit node
- BasicBlock *ExitNode = getAnalysis<UnifyFunctionExitNodes>().getExitNode();
+bool ProfilePaths::runOnFunction(Function &F){
+
+ static int mn = -1;
+ static int CountCounter = 1;
+ if(F.isExternal()) {
+ return false;
+ }
+
+ //increment counter for instrumented functions. mn is now function#
+ mn++;
- // iterating over BBs and making graph
- std::set<Node *> nodes;
- std::set<Edge> edges;
+ // Transform the cfg s.t. we have just one exit node
+ BasicBlock *ExitNode =
+ getAnalysis<UnifyFunctionExitNodes>().getReturnBlock();
+
+ //iterating over BBs and making graph
+ std::vector<Node *> nodes;
+ std::vector<Edge> edges;
+
Node *tmp;
- Node *exitNode, *startNode;
+ Node *exitNode = 0, *startNode = 0;
- // The nodes must be uniquesly identified:
+ // The nodes must be uniquely identified:
// That is, no two nodes must hav same BB*
- // First enter just nodes: later enter edges
- for (Function::iterator BB = M->begin(), BE=M->end(); BB != BE; ++BB){
- Node *nd=new Node(*BB);
- nodes.insert(nd);
- if(*BB==ExitNode)
+ for (Function::iterator BB = F.begin(), BE = F.end(); BB != BE; ++BB) {
+ Node *nd=new Node(BB);
+ nodes.push_back(nd);
+ if(&*BB == ExitNode)
exitNode=nd;
- if(*BB==M->front())
+ if(BB==F.begin())
startNode=nd;
}
- // now do it againto insert edges
- for (Function::iterator BB = M->begin(), BE=M->end(); BB != BE; ++BB){
- Node *nd=findBB(nodes, *BB);
+ // now do it again to insert edges
+ for (Function::iterator BB = F.begin(), BE = F.end(); BB != BE; ++BB){
+ Node *nd=findBB(nodes, BB);
assert(nd && "No node for this edge!");
- for(BasicBlock::succ_iterator s=succ_begin(*BB), se=succ_end(*BB);
- s!=se; ++s){
+
+ for(succ_iterator s=succ_begin(BB), se=succ_end(BB); s!=se; ++s){
Node *nd2=findBB(nodes,*s);
assert(nd2 && "No node for this edge!");
Edge ed(nd,nd2,0);
- edges.insert(ed);
+ edges.push_back(ed);
}
}
Graph g(nodes,edges, startNode, exitNode);
#ifdef DEBUG_PATH_PROFILES
+ std::cerr<<"Original graph\n";
printGraph(g);
#endif
- BasicBlock *fr=M->front();
+ BasicBlock *fr = &F.front();
+
+ // The graph is made acyclic: this is done
+ // by removing back edges for now, and adding them later on
+ std::vector<Edge> be;
+ std::map<Node *, int> nodePriority; //it ranks nodes in depth first order traversal
+ g.getBackEdges(be, nodePriority);
- // If only one BB, don't instrument
- if (M->getBasicBlocks().size() == 1) {
- // The graph is made acyclic: this is done
- // by removing back edges for now, and adding them later on
- vector<Edge> be;
- g.getBackEdges(be);
#ifdef DEBUG_PATH_PROFILES
- cerr<<"Backedges:"<<be.size()<<endl;
+ std::cerr<<"BackEdges-------------\n";
+ for (std::vector<Edge>::iterator VI=be.begin(); VI!=be.end(); ++VI){
+ printEdge(*VI);
+ cerr<<"\n";
+ }
+ std::cerr<<"------\n";
#endif
- // Now we need to reflect the effect of back edges
- // This is done by adding dummy edges
- // If a->b is a back edge
- // Then we add 2 back edges for it:
- // 1. from root->b (in vector stDummy)
- // and 2. from a->exit (in vector exDummy)
- vector<Edge> stDummy;
- vector<Edge> exDummy;
- addDummyEdges(stDummy, exDummy, g, be);
-
- // Now, every edge in the graph is assigned a weight
- // This weight later adds on to assign path
- // numbers to different paths in the graph
- // All paths for now are acyclic,
- // since no back edges in the graph now
- // numPaths is the number of acyclic paths in the graph
- int numPaths=valueAssignmentToEdges(g);
-
- // create instruction allocation r and count
- // r is the variable that'll act like an accumulator
- // all along the path, we just add edge values to r
- // and at the end, r reflects the path number
- // count is an array: count[x] would store
- // the number of executions of path numbered x
- Instruction *rVar=new
- AllocaInst(PointerType::get(Type::IntTy),
- ConstantUInt::get(Type::UIntTy,1),"R");
-
- Instruction *countVar=new
- AllocaInst(PointerType::get(Type::IntTy),
- ConstantUInt::get(Type::UIntTy, numPaths), "Count");
-
- // insert initialization code in first (entry) BB
- // this includes initializing r and count
- insertInTopBB(M->getEntryNode(),numPaths, rVar, countVar);
+
+#ifdef DEBUG_PATH_PROFILES
+ cerr<<"Backedges:"<<be.size()<<endl;
+#endif
+ //Now we need to reflect the effect of back edges
+ //This is done by adding dummy edges
+ //If a->b is a back edge
+ //Then we add 2 back edges for it:
+ //1. from root->b (in vector stDummy)
+ //and 2. from a->exit (in vector exDummy)
+ std::vector<Edge> stDummy;
+ std::vector<Edge> exDummy;
+ addDummyEdges(stDummy, exDummy, g, be);
+
+#ifdef DEBUG_PATH_PROFILES
+ std::cerr<<"After adding dummy edges\n";
+ printGraph(g);
+#endif
+
+ // Now, every edge in the graph is assigned a weight
+ // This weight later adds on to assign path
+ // numbers to different paths in the graph
+ // All paths for now are acyclic,
+ // since no back edges in the graph now
+ // numPaths is the number of acyclic paths in the graph
+ int numPaths=valueAssignmentToEdges(g, nodePriority, be);
+
+ //if(numPaths<=1) return false;
+
+ static GlobalVariable *threshold = NULL;
+ static bool insertedThreshold = false;
+
+ if(!insertedThreshold){
+ threshold = new GlobalVariable(Type::IntTy, false,
+ GlobalValue::ExternalLinkage, 0,
+ "reopt_threshold");
+
+ F.getParent()->getGlobalList().push_back(threshold);
+ insertedThreshold = true;
+ }
+
+ assert(threshold && "GlobalVariable threshold not defined!");
+
+
+ if(fr->getParent()->getName() == "main"){
+ //initialize threshold
+
+ // FIXME: THIS IS HORRIBLY BROKEN. FUNCTION PASSES CANNOT DO THIS, EXCEPT
+ // IN THEIR INITIALIZE METHOD!!
+ Function *initialize =
+ F.getParent()->getOrInsertFunction("reoptimizerInitialize", Type::VoidTy,
+ PointerType::get(Type::IntTy), 0);
- // now process the graph: get path numbers,
- // get increments along different paths,
- // and assign "increments" and "updates" (to r and count)
- // "optimally". Finally, insert llvm code along various edges
- processGraph(g, rVar, countVar, be, stDummy, exDummy);
+ std::vector<Value *> trargs;
+ trargs.push_back(threshold);
+ new CallInst(initialize, trargs, "", fr->begin());
}
+
+ if(numPaths<=1 || numPaths >5000) return false;
+
+#ifdef DEBUG_PATH_PROFILES
+ printGraph(g);
+#endif
+
+ //create instruction allocation r and count
+ //r is the variable that'll act like an accumulator
+ //all along the path, we just add edge values to r
+ //and at the end, r reflects the path number
+ //count is an array: count[x] would store
+ //the number of executions of path numbered x
+
+ Instruction *rVar=new
+ AllocaInst(Type::IntTy,
+ ConstantUInt::get(Type::UIntTy,1),"R");
+
+ //Instruction *countVar=new
+ //AllocaInst(Type::IntTy,
+ // ConstantUInt::get(Type::UIntTy, numPaths), "Count");
+
+ //initialize counter array!
+ std::vector<Constant*> arrayInitialize;
+ for(int xi=0; xi<numPaths; xi++)
+ arrayInitialize.push_back(ConstantSInt::get(Type::IntTy, 0));
+
+ const ArrayType *ATy = ArrayType::get(Type::IntTy, numPaths);
+ Constant *initializer = ConstantArray::get(ATy, arrayInitialize);
+ char tempChar[20];
+ sprintf(tempChar, "Count%d", CountCounter);
+ CountCounter++;
+ std::string countStr = tempChar;
+ GlobalVariable *countVar = new GlobalVariable(ATy, false,
+ GlobalValue::InternalLinkage,
+ initializer, countStr,
+ F.getParent());
+
+ // insert initialization code in first (entry) BB
+ // this includes initializing r and count
+ insertInTopBB(&F.getEntryBlock(), numPaths, rVar, threshold);
+
+ //now process the graph: get path numbers,
+ //get increments along different paths,
+ //and assign "increments" and "updates" (to r and count)
+ //"optimally". Finally, insert llvm code along various edges
+ processGraph(g, rVar, countVar, be, stDummy, exDummy, numPaths, mn,
+ threshold);
+
return true; // Always modifies function
}
+
+} // End llvm namespace