split retracing into a separate file
[oota-llvm.git] / lib / Transforms / Instrumentation / TraceValues.cpp
index 0cd395b404ca555b5752dfacf82169c5074851b8..5abfe272387497ebce6883cc7d039420d7cd8676 100644 (file)
-// $Id$
-//***************************************************************************
-// File:
-//     TraceValues.cpp
-// 
-// Purpose:
-//      Support for inserting LLVM code to print values at basic block
-//      and method exits.  Also exports functions to create a call
-//      "printf" instruction with one of the signatures listed below.
-// 
-// History:
-//     10/11/01         -  Vikram Adve  -  Created
-//**************************************************************************/
-
+//===- TraceValues.cpp - Value Tracing for debugging -------------*- C++ -*--=//
+//
+// Support for inserting LLVM code to print values at basic block and function
+// exits.
+//
+//===----------------------------------------------------------------------===//
 
 #include "llvm/Transforms/Instrumentation/TraceValues.h"
-#include "llvm/GlobalVariable.h"
-#include "llvm/ConstPoolVals.h"
-#include "llvm/Type.h"
+#include "llvm/Constants.h"
 #include "llvm/DerivedTypes.h"
-#include "llvm/Instruction.h"
+#include "llvm/iMemory.h"
 #include "llvm/iTerminators.h"
 #include "llvm/iOther.h"
-#include "llvm/BasicBlock.h"
-#include "llvm/Method.h"
 #include "llvm/Module.h"
-#include "llvm/SymbolTable.h"
-#include "llvm/Support/HashExtras.h"
-#include <hash_map>
-#include <strstream.h>
+#include "llvm/Pass.h"
+#include "llvm/Assembly/Writer.h"
+#include "Support/CommandLine.h"
+#include "Support/StringExtras.h"
+#include <algorithm>
+#include <sstream>
+using std::vector;
+using std::string;
 
+static cl::opt<bool>
+DisablePtrHashing("tracedisablehashdisable", cl::Hidden,
+                  cl::desc("Disable pointer hashing"));
 
-//*********************** Internal Data Structures *************************/
+static cl::list<string>
+TraceFuncName("tracefunc", cl::desc("trace only specific functions"),
+              cl::value_desc("function"), cl::Hidden);
 
-const char* const PRINTF = "printf";
+static void TraceValuesAtBBExit(BasicBlock *BB,
+                                Function *Printf, Function* HashPtrToSeqNum,
+                                vector<Instruction*> *valuesStoredInFunction);
 
-#undef DONT_EMBED_STRINGS_IN_FMT
+// We trace a particular function if no functions to trace were specified
+// or if the function is in the specified list.
+// 
+inline static bool
+TraceThisFunction(Function &func)
+{
+  if (TraceFuncName.size() == 0)
+    return true;
 
+  return std::find(TraceFuncName.begin(), TraceFuncName.end(), func.getName())
+                  != TraceFuncName.end();
+}
 
-//************************** Internal Functions ****************************/
 
-#undef USE_PTRREF
-#ifdef USE_PTRREF
-static inline ConstPoolPointerReference*
-GetStringRef(Module* module, const char* str)
-{
-  static hash_map<string, ConstPoolPointerReference*> stringRefCache;
-  static Module* lastModule = NULL;
+namespace {
+  struct ExternalFuncs {
+    Function *PrintfFunc, *HashPtrFunc, *ReleasePtrFunc;
+    Function *RecordPtrFunc, *PushOnEntryFunc, *ReleaseOnReturnFunc;
+    void doInitialization(Module &M); // Add prototypes for external functions
+  };
   
-  if (lastModule != module)
-    { // Let's make sure we create separate global references in each module
-      stringRefCache.clear();
-      lastModule = module;
+  class InsertTraceCode : public FunctionPass {
+  protected:
+    ExternalFuncs externalFuncs;
+  public:
+    
+    // Add a prototype for runtime functions not already in the program.
+    //
+    bool doInitialization(Module &M);
+    
+    //--------------------------------------------------------------------------
+    // Function InsertCodeToTraceValues
+    // 
+    // Inserts tracing code for all live values at basic block and/or function
+    // exits as specified by `traceBasicBlockExits' and `traceFunctionExits'.
+    //
+    bool doit(Function *M);
+
+    virtual void handleBasicBlock(BasicBlock *BB, vector<Instruction*> &VI) = 0;
+
+    // runOnFunction - This method does the work.
+    //
+    bool runOnFunction(Function &F);
+
+    virtual void getAnalysisUsage(AnalysisUsage &AU) const {
+      AU.preservesCFG();
     }
-  
-  ConstPoolPointerReference* result = stringRefCache[str];
-  if (result == NULL)
-    {
-      ConstPoolArray* charArray = ConstPoolArray::get(str);
-      GlobalVariable* stringVar =
-        new GlobalVariable(charArray->getType(),/*isConst*/true,charArray,str);
-      module->getGlobalList().push_back(stringVar);
-      result = ConstPoolPointerReference::get(stringVar);
-      assert(result && "Failed to create reference to string constant");
-      stringRefCache[str] = result;
+  };
+
+  struct FunctionTracer : public InsertTraceCode {
+    // Ignore basic blocks here...
+    virtual void handleBasicBlock(BasicBlock *BB, vector<Instruction*> &VI) {}
+  };
+
+  struct BasicBlockTracer : public InsertTraceCode {
+    // Trace basic blocks here...
+    virtual void handleBasicBlock(BasicBlock *BB, vector<Instruction*> &VI) {
+      TraceValuesAtBBExit(BB, externalFuncs.PrintfFunc,
+                          externalFuncs.HashPtrFunc, &VI);
     }
-  
-  return result;
+  };
+
+  // Register the passes...
+  RegisterOpt<FunctionTracer>  X("tracem","Insert Function trace code only");
+  RegisterOpt<BasicBlockTracer> Y("trace","Insert BB and Function trace code");
+} // end anonymous namespace
+
+
+Pass *createTraceValuesPassForFunction() {     // Just trace functions
+  return new FunctionTracer();
 }
-#endif USE_PTRREF
 
-static inline GlobalVariable*
-GetStringRef(Module* module, const char* str)
-{
-  static hash_map<string, GlobalVariable*> stringRefCache;
-  static Module* lastModule = NULL;
+Pass *createTraceValuesPassForBasicBlocks() {  // Trace BB's and functions
+  return new BasicBlockTracer();
+}
+
+
+// Add a prototype for external functions used by the tracing code.
+//
+void ExternalFuncs::doInitialization(Module &M) {
+  const Type *SBP = PointerType::get(Type::SByteTy);
+  const FunctionType *MTy =
+    FunctionType::get(Type::IntTy, vector<const Type*>(1, SBP), true);
+  PrintfFunc = M.getOrInsertFunction("printf", MTy);
+
+  // uint (sbyte*)
+  const FunctionType *hashFuncTy =
+    FunctionType::get(Type::UIntTy, vector<const Type*>(1, SBP), false);
+  HashPtrFunc = M.getOrInsertFunction("HashPointerToSeqNum", hashFuncTy);
   
-  if (lastModule != module)
-    { // Let's make sure we create separate global references in each module
-      stringRefCache.clear();
-      lastModule = module;
-    }
+  // void (sbyte*)
+  const FunctionType *voidSBPFuncTy =
+    FunctionType::get(Type::VoidTy, vector<const Type*>(1, SBP), false);
   
-  GlobalVariable* result = stringRefCache[str];
-  if (result == NULL)
-    {
-      ConstPoolArray* charArray = ConstPoolArray::get(str);
-      GlobalVariable* stringVar =
-        new GlobalVariable(charArray->getType(),/*isConst*/true,charArray);
-      module->getGlobalList().push_back(stringVar);
-      result = stringVar;
-      // result = ConstPoolPointerReference::get(stringVar);
-      assert(result && "Failed to create reference to string constant");
-      stringRefCache[str] = result;
-    }
+  ReleasePtrFunc = M.getOrInsertFunction("ReleasePointerSeqNum", voidSBPFuncTy);
+  RecordPtrFunc  = M.getOrInsertFunction("RecordPointer", voidSBPFuncTy);
+  
+  const FunctionType *voidvoidFuncTy =
+    FunctionType::get(Type::VoidTy, vector<const Type*>(), false);
   
-  return result;
+  PushOnEntryFunc = M.getOrInsertFunction("PushPointerSet", voidvoidFuncTy);
+  ReleaseOnReturnFunc = M.getOrInsertFunction("ReleasePointersPopSet",
+                                               voidvoidFuncTy);
 }
 
 
-static inline bool
-TraceThisOpCode(unsigned opCode)
-{
+// Add a prototype for external functions used by the tracing code.
+//
+bool InsertTraceCode::doInitialization(Module &M) {
+  externalFuncs.doInitialization(M);
+  return false;
+}
+
+
+static inline GlobalVariable *getStringRef(Module *M, const string &str) {
+  // Create a constant internal string reference...
+  Constant *Init = ConstantArray::get(str);
+
+  // Create the global variable and record it in the module
+  // The GV will be renamed to a unique name if needed.
+  GlobalVariable *GV = new GlobalVariable(Init->getType(), true, true, Init,
+                                          "trstr");
+  M->getGlobalList().push_back(GV);
+  return GV;
+}
+
+
+// 
+// Check if this instruction has any uses outside its basic block,
+// or if it used by either a Call or Return instruction.
+// 
+static inline bool LiveAtBBExit(const Instruction* I) {
+  const BasicBlock *BB = I->getParent();
+  for (Value::use_const_iterator U = I->use_begin(); U != I->use_end(); ++U)
+    if (const Instruction *UI = dyn_cast<Instruction>(*U))
+      if (UI->getParent() != BB || isa<ReturnInst>(UI))
+        return true;
+
+  return false;
+}
+
+
+static inline bool TraceThisOpCode(unsigned opCode) {
   // Explicitly test for opCodes *not* to trace so that any new opcodes will
-  // be traced by default (or will fail in a later assertion on VoidTy)
+  // be traced by default (VoidTy's are already excluded)
   // 
   return (opCode  < Instruction::FirstOtherOp &&
-          opCode != Instruction::Ret &&
-          opCode != Instruction::Br &&
-          opCode != Instruction::Switch &&
-          opCode != Instruction::Free &&
           opCode != Instruction::Alloca &&
-          opCode != Instruction::Store &&
           opCode != Instruction::PHINode &&
           opCode != Instruction::Cast);
 }
 
 
-static void
-FindValuesToTraceInBB(BasicBlock* bb,
-                      vector<Value*>& valuesToTraceInBB)
-{
-  for (BasicBlock::iterator II = bb->begin(); II != bb->end(); ++II)
-    if ((*II)->getType()->isPrimitiveType() &&
-        TraceThisOpCode((*II)->getOpcode()))
-      {
-        valuesToTraceInBB.push_back(*II);
-      }
+static bool ShouldTraceValue(const Instruction *I) {
+  return
+    I->getType() != Type::VoidTy && LiveAtBBExit(I) &&
+    TraceThisOpCode(I->getOpcode());
 }
 
+static string getPrintfCodeFor(const Value *V) {
+  if (V == 0) return "";
+  if (V->getType()->isFloatingPoint())
+    return "%g";
+  else if (V->getType() == Type::LabelTy)
+    return "0x%p";
+  else if (isa<PointerType>(V->getType()))
+    return DisablePtrHashing ? "0x%p" : "%d";
+  else if (V->getType()->isIntegral())
+    return "%d";
+  
+  assert(0 && "Illegal value to print out...");
+  return "";
+}
 
-// 
-// Insert print instructions at the end of the basic block *bb
-// for each value in valueVec[].  *bb must postdominate the block
-// in which the value is computed; this is not checked here.
-// 
-static void
-TraceValuesAtBBExit(const vector<Value*>& valueVec,
-                    BasicBlock* bb,
-                    Module* module,
-                    unsigned int indent,
-                    bool isMethodExit)
-{
-  // Get an iterator to point to the insertion location
-  // 
-  BasicBlock::InstListType& instList = bb->getInstList();
-  TerminatorInst* termInst = bb->getTerminator(); 
-  BasicBlock::InstListType::iterator here = instList.end();
-  while ((*here) != termInst && here != instList.begin())
-    --here;
-  assert((*here) == termInst);
+
+static void InsertPrintInst(Value *V, BasicBlock *BB, Instruction *InsertBefore,
+                            string Message,
+                            Function *Printf, Function* HashPtrToSeqNum) {
+  // Escape Message by replacing all % characters with %% chars.
+  unsigned Offset = 0;
+  while ((Offset = Message.find('%', Offset)) != string::npos) {
+    Message.replace(Offset, 1, "%%");
+    Offset += 2;  // Skip over the new %'s
+  }
+
+  Module *Mod = BB->getParent()->getParent();
+
+  // Turn the marker string into a global variable...
+  GlobalVariable *fmtVal = getStringRef(Mod, Message+getPrintfCodeFor(V)+"\n");
+
+  // Turn the format string into an sbyte *
+  Instruction *GEP = 
+    new GetElementPtrInst(fmtVal,
+                          vector<Value*>(2,ConstantSInt::get(Type::LongTy, 0)),
+                          "trstr", InsertBefore);
   
-  // Insert a print instruction for each value.
-  // 
-  for (unsigned i=0, N=valueVec.size(); i < N; i++)
-    {
-      Instruction* traceInstr =
-        CreatePrintInstr(valueVec[i], bb, module, indent, isMethodExit);
-      here = instList.insert(here, traceInstr);
-    }
+  // Insert a call to the hash function if this is a pointer value
+  if (V && isa<PointerType>(V->getType()) && !DisablePtrHashing) {
+    const Type *SBP = PointerType::get(Type::SByteTy);
+    if (V->getType() != SBP)     // Cast pointer to be sbyte*
+      V = new CastInst(V, SBP, "Hash_cast", InsertBefore);
+
+    vector<Value*> HashArgs(1, V);
+    V = new CallInst(HashPtrToSeqNum, HashArgs, "ptrSeqNum", InsertBefore);
+  }
+  
+  // Insert the first print instruction to print the string flag:
+  vector<Value*> PrintArgs;
+  PrintArgs.push_back(GEP);
+  if (V) PrintArgs.push_back(V);
+  new CallInst(Printf, PrintArgs, "trace", InsertBefore);
 }
+                            
 
-static void
-InsertCodeToShowMethodEntry(BasicBlock* entryBB)
-{
+static void InsertVerbosePrintInst(Value *V, BasicBlock *BB,
+                                   Instruction *InsertBefore,
+                                   const string &Message, Function *Printf,
+                                   Function* HashPtrToSeqNum) {
+  std::ostringstream OutStr;
+  if (V) WriteAsOperand(OutStr, V);
+  InsertPrintInst(V, BB, InsertBefore, Message+OutStr.str()+" = ",
+                  Printf, HashPtrToSeqNum);
 }
 
-static void
-InsertCodeToShowMethodExit(BasicBlock* exitBB)
-{
+static void 
+InsertReleaseInst(Value *V, BasicBlock *BB,
+                  Instruction *InsertBefore,
+                  Function* ReleasePtrFunc) {
+  
+  const Type *SBP = PointerType::get(Type::SByteTy);
+  if (V->getType() != SBP)    // Cast pointer to be sbyte*
+    V = new CastInst(V, SBP, "RPSN_cast", InsertBefore);
+
+  vector<Value*> releaseArgs(1, V);
+  new CallInst(ReleasePtrFunc, releaseArgs, "", InsertBefore);
 }
 
+static void 
+InsertRecordInst(Value *V, BasicBlock *BB,
+                 Instruction *InsertBefore,
+                 Function* RecordPtrFunc) {
+    const Type *SBP = PointerType::get(Type::SByteTy);
+  if (V->getType() != SBP)     // Cast pointer to be sbyte*
+    V = new CastInst(V, SBP, "RP_cast", InsertBefore);
 
-//************************** External Functions ****************************/
+  vector<Value*> releaseArgs(1, V);
+  new CallInst(RecordPtrFunc, releaseArgs, "", InsertBefore);
+}
 
+// Look for alloca and free instructions. These are the ptrs to release.
+// Release the free'd pointers immediately.  Record the alloca'd pointers
+// to be released on return from the current function.
 // 
-// The signatures of the print methods supported are:
-//   int printf(ubyte*,  ubyte*,  ubyte*,  ubyte*,  int      intValue)
-//   int printf(ubyte*,  ubyte*,  ubyte*,  ubyte*,  unsigned uintValue)
-//   int printf(ubyte*,  ubyte*,  ubyte*,  ubyte*,  float    floatValue)
-//   int printf(ubyte*,  ubyte*,  ubyte*,  ubyte*,  double   doubleValue)
-//   int printf(ubyte*,  ubyte*,  ubyte*,  ubyte*,  char*    stringValue)
-//   int printf(ubyte*,  ubyte*,  ubyte*,  ubyte*,  void*    ptrValue)
-// 
-// The invocation should be:
-//       call "printf"(fmt, bbName, valueName, valueTypeName, value).
-// 
-Method*
-GetPrintMethodForType(Module* module, const Type* valueType)
-{
-#ifdef DONT_EMBED_STRINGS_IN_FMT
-  static const int LASTARGINDEX = 4;
-#else
-  static const int LASTARGINDEX = 1;
-#endif
-  static PointerType* ubytePtrTy = NULL;
-  static vector<const Type*> argTypesVec(LASTARGINDEX + 1);
-  
-  if (ubytePtrTy == NULL)
-    { // create these once since they are invariant
-      ubytePtrTy = PointerType::get(ArrayType::get(Type::UByteTy));
-      argTypesVec[0] = ubytePtrTy;
-#ifdef DONT_EMBED_STRINGS_IN_FMT
-      argTypesVec[1] = ubytePtrTy;
-      argTypesVec[2] = ubytePtrTy;
-      argTypesVec[3] = ubytePtrTy;
-#endif DONT_EMBED_STRINGS_IN_FMT
-    }
+static void
+ReleasePtrSeqNumbers(BasicBlock *BB,
+                     ExternalFuncs& externalFuncs) {
   
-  SymbolTable* symtab = module->getSymbolTable();
-  argTypesVec[LASTARGINDEX] = valueType;
-  MethodType* printMethodTy = MethodType::get(Type::IntTy, argTypesVec,
-                                              /*isVarArg*/ false);
+  for (BasicBlock::iterator II=BB->begin(), IE = BB->end(); II != IE; ++II)
+    if (FreeInst *FI = dyn_cast<FreeInst>(&*II))
+      InsertReleaseInst(FI->getOperand(0), BB, FI,externalFuncs.ReleasePtrFunc);
+    else if (AllocaInst *AI = dyn_cast<AllocaInst>(&*II))
+      InsertRecordInst(AI, BB, AI->getNext(), externalFuncs.RecordPtrFunc);
+}  
+
+
+// Insert print instructions at the end of basic block BB for each value
+// computed in BB that is live at the end of BB,
+// or that is stored to memory in BB.
+// If the value is stored to memory, we load it back before printing it
+// We also return all such loaded values in the vector valuesStoredInFunction
+// for printing at the exit from the function.  (Note that in each invocation
+// of the function, this will only get the last value stored for each static
+// store instruction).
+// 
+static void TraceValuesAtBBExit(BasicBlock *BB,
+                                Function *Printf, Function* HashPtrToSeqNum,
+                                vector<Instruction*> *valuesStoredInFunction) {
+  // Get an iterator to point to the insertion location, which is
+  // just before the terminator instruction.
+  // 
+  TerminatorInst *InsertPos = BB->getTerminator();
   
-  Method* printMethod =
-    cast<Method>(symtab->lookup(PointerType::get(printMethodTy), PRINTF));
-  if (printMethod == NULL)
-    { // Create a new method and add it to the module
-      printMethod = new Method(printMethodTy, PRINTF);
-      module->getMethodList().push_back(printMethod);
-      
-      // Create the argument list for the method so that the full signature
-      // can be declared.  The args can be anonymous.
-      Method::ArgumentListType &argList = printMethod->getArgumentList();
-      for (unsigned i=0; i < argTypesVec.size(); ++i)
-        argList.push_back(new MethodArgument(argTypesVec[i]));
+  std::ostringstream OutStr;
+  WriteAsOperand(OutStr, BB, false);
+  InsertPrintInst(0, BB, InsertPos, "LEAVING BB:" + OutStr.str(),
+                  Printf, HashPtrToSeqNum);
+
+  // Insert a print instruction for each instruction preceding InsertPos.
+  // The print instructions must go before InsertPos, so we use the
+  // instruction *preceding* InsertPos to check when to terminate the loop.
+  // 
+  for (BasicBlock::iterator II = BB->begin(); &*II != InsertPos; ++II) {
+    if (StoreInst *SI = dyn_cast<StoreInst>(&*II)) {
+      assert(valuesStoredInFunction &&
+             "Should not be printing a store instruction at function exit");
+      LoadInst *LI = new LoadInst(SI->getPointerOperand(), "reload." +
+                                  SI->getPointerOperand()->getName(),
+                                  InsertPos);
+      valuesStoredInFunction->push_back(LI);
     }
-  
-  return printMethod;
+    if (ShouldTraceValue(II))
+      InsertVerbosePrintInst(II, BB, InsertPos, "  ", Printf, HashPtrToSeqNum);
+  }
 }
 
+static inline void InsertCodeToShowFunctionEntry(Function &F, Function *Printf,
+                                                 Function* HashPtrToSeqNum){
+  // Get an iterator to point to the insertion location
+  BasicBlock &BB = F.getEntryNode();
+  Instruction *InsertPos = BB.begin();
 
-Instruction*
-CreatePrintInstr(Value* val,
-                 const BasicBlock* bb,
-                 Module* module,
-                 unsigned int indent,
-                 bool isMethodExit)
-{
-  strstream fmtString, scopeNameString, valNameString;
-  vector<Value*> paramList;
-  const Type* valueType = val->getType();
-  Method* printMethod = GetPrintMethodForType(module, valueType);
-  
-  if (! valueType->isPrimitiveType() ||
-      valueType->getPrimitiveID() == Type::VoidTyID ||
-      valueType->getPrimitiveID() == Type::TypeTyID ||
-      valueType->getPrimitiveID() == Type::LabelTyID)
-    {
-      assert(0 && "Unsupported type for printing");
-      return NULL;
-    }
-  
-  const Value* scopeToUse = (isMethodExit)? (const Value*) bb->getParent()
-                                          : (const Value*) bb;
-  if (scopeToUse->hasName())
-    scopeNameString << scopeToUse->getName() << ends;
-  else
-    scopeNameString << scopeToUse << ends;
-  
-  if (val->hasName())
-    valNameString << val->getName() << ends;
-  else
-    valNameString << val << ends;
-    
-  for (unsigned i=0; i < indent; i++)
-    fmtString << " ";
-  
-#undef DONT_EMBED_STRINGS_IN_FMT
-#ifdef DONT_EMBED_STRINGS_IN_FMT
-  fmtString << " At exit of "
-            << ((isMethodExit)? "Method " : "BB ")
-            << "%s : val %s = %s ";
-  
-  GlobalVariable* scopeNameVal = GetStringRef(module, scopeNameString.str());
-  GlobalVariable* valNameVal   = GetStringRef(module,valNameString.str());
-  GlobalVariable* typeNameVal  = GetStringRef(module,
-                                     val->getType()->getDescription().c_str());
-#else
-  fmtString << " At exit of "
-            << ((isMethodExit)? "Method " : "BB ")
-            << scopeNameString.str() << " : "
-            << valNameString.str()   << " = "
-            << val->getType()->getDescription().c_str();
-#endif DONT_EMBED_STRINGS_IN_FMT
-  
-  switch(valueType->getPrimitiveID())
-    {
-    case Type::BoolTyID:
-    case Type::UByteTyID: case Type::UShortTyID:
-    case Type::UIntTyID:  case Type::ULongTyID:
-    case Type::SByteTyID: case Type::ShortTyID:
-    case Type::IntTyID:   case Type::LongTyID:
-      fmtString << " %d\0A";
-      break;
-      
-    case Type::FloatTyID:     case Type::DoubleTyID:
-      fmtString << " %g\0A";
-      break;
-      
-    case Type::PointerTyID:
-      fmtString << " %p\0A";
-      break;
-      
-    default:
-      assert(0 && "Should not get here.  Check the IF expression above");
-      return NULL;
-    }
-  
-  fmtString << ends;
-  GlobalVariable* fmtVal = GetStringRef(module, fmtString.str());
-  
-#ifdef DONT_EMBED_STRINGS_IN_FMT
-  paramList.push_back(fmtVal);
-  paramList.push_back(scopeNameVal);
-  paramList.push_back(valNameVal);
-  paramList.push_back(typeNameVal);
-  paramList.push_back(val);
-#else
-  paramList.push_back(fmtVal);
-  paramList.push_back(val);
-#endif DONT_EMBED_STRINGS_IN_FMT
+  std::ostringstream OutStr;
+  WriteAsOperand(OutStr, &F, true);
+  InsertPrintInst(0, &BB, InsertPos, "ENTERING FUNCTION: " + OutStr.str(),
+                  Printf, HashPtrToSeqNum);
+
+  // Now print all the incoming arguments
+  unsigned ArgNo = 0;
+  for (Function::aiterator I = F.abegin(), E = F.aend(); I != E; ++I, ++ArgNo){
+    InsertVerbosePrintInst(I, &BB, InsertPos,
+                           "  Arg #" + utostr(ArgNo) + ": ", Printf,
+                           HashPtrToSeqNum);
+  }
+}
+
+
+static inline void InsertCodeToShowFunctionExit(BasicBlock *BB,
+                                                Function *Printf,
+                                                Function* HashPtrToSeqNum) {
+  // Get an iterator to point to the insertion location
+  ReturnInst *Ret = cast<ReturnInst>(BB->getTerminator());
   
-  free(fmtString.str());
-  free(scopeNameString.str());
-  free(valNameString.str());
+  std::ostringstream OutStr;
+  WriteAsOperand(OutStr, BB->getParent(), true);
+  InsertPrintInst(0, BB, Ret, "LEAVING  FUNCTION: " + OutStr.str(),
+                  Printf, HashPtrToSeqNum);
   
-  return new CallInst(printMethod, paramList);
+  // print the return value, if any
+  if (BB->getParent()->getReturnType() != Type::VoidTy)
+    InsertPrintInst(Ret->getReturnValue(), BB, Ret, "  Returning: ",
+                    Printf, HashPtrToSeqNum);
 }
 
 
-void
-InsertCodeToTraceValues(Method* method,
-                        bool traceBasicBlockExits,
-                        bool traceMethodExits)
-{
-  vector<Value*> valuesToTraceInMethod;
-  Module* module = method->getParent();
-  BasicBlock* exitBB = NULL;
+bool InsertTraceCode::runOnFunction(Function &F) {
+  if (!TraceThisFunction(F))
+    return false;
   
-  if (method->isExternal() ||
-      (! traceBasicBlockExits && ! traceMethodExits))
-    return;
+  vector<Instruction*> valuesStoredInFunction;
+  vector<BasicBlock*>  exitBlocks;
+
+  // Insert code to trace values at function entry
+  InsertCodeToShowFunctionEntry(F, externalFuncs.PrintfFunc,
+                                externalFuncs.HashPtrFunc);
   
-  if (traceMethodExits)
-    {
-      InsertCodeToShowMethodEntry(method->getEntryNode());
-#ifdef TODO_LATER
-      exitBB = method->getExitNode();
-#endif
-    }
+  // Push a pointer set for recording alloca'd pointers at entry.
+  if (!DisablePtrHashing)
+    new CallInst(externalFuncs.PushOnEntryFunc, vector<Value*>(), "",
+                 F.getEntryNode().begin());
+
+  for (Function::iterator BB = F.begin(); BB != F.end(); ++BB) {
+    if (isa<ReturnInst>(BB->getTerminator()))
+      exitBlocks.push_back(BB); // record this as an exit block
+
+    // Insert trace code if this basic block is interesting...
+    handleBasicBlock(BB, valuesStoredInFunction);
+
+    if (!DisablePtrHashing)          // release seq. numbers on free/ret
+      ReleasePtrSeqNumbers(BB, externalFuncs);
+  }
   
-  for (Method::iterator BI = method->begin(); BI != method->end(); ++BI)
+  for (unsigned i=0; i != exitBlocks.size(); ++i)
     {
-      BasicBlock* bb = *BI;
-      vector<Value*> valuesToTraceInBB;
-      FindValuesToTraceInBB(bb, valuesToTraceInBB);
+      // Insert code to trace values at function exit
+      InsertCodeToShowFunctionExit(exitBlocks[i], externalFuncs.PrintfFunc,
+                                   externalFuncs.HashPtrFunc);
       
-      if (traceBasicBlockExits && bb != exitBB)
-        TraceValuesAtBBExit(valuesToTraceInBB, bb, module,
-                            /*indent*/ 4, /*isMethodExit*/ false);
-      
-      if (traceMethodExits)
-        valuesToTraceInMethod.insert(valuesToTraceInMethod.end(),
-                                     valuesToTraceInBB.begin(),
-                                     valuesToTraceInBB.end());
+      // Release all recorded pointers before RETURN.  Do this LAST!
+      if (!DisablePtrHashing)
+        new CallInst(externalFuncs.ReleaseOnReturnFunc, vector<Value*>(), "",
+                     exitBlocks[i]->getTerminator());
     }
   
-  if (traceMethodExits)
-    {
-      TraceValuesAtBBExit(valuesToTraceInMethod, exitBB, module,
-                          /*indent*/ 0, /*isMethodExit*/ true);
-      InsertCodeToShowMethodExit(exitBB);
-    }
+  return true;
 }