-// $Id$
-//***************************************************************************
-// 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/Function.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/StringExtras.h"
+#include <sstream>
+using std::vector;
+using std::string;
+namespace {
+ class InsertTraceCode : public FunctionPass {
+ bool TraceBasicBlockExits, TraceFunctionExits;
+ Function *PrintfFunc;
+ public:
+ InsertTraceCode(bool traceBasicBlockExits, bool traceFunctionExits)
+ : TraceBasicBlockExits(traceBasicBlockExits),
+ TraceFunctionExits(traceFunctionExits) {}
+
+ // Add a prototype for printf if it is 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'.
+ //
+ static bool doit(Function *M, bool traceBasicBlockExits,
+ bool traceFunctionExits, Function *Printf);
+
+ // runOnFunction - This method does the work.
+ //
+ bool runOnFunction(Function *F) {
+ return doit(F, TraceBasicBlockExits, TraceFunctionExits, PrintfFunc);
+ }
+ };
+} // end anonymous namespace
-//*********************** Internal Data Structures *************************/
-const char* const PRINTF = "printf";
+Pass *createTraceValuesPassForFunction() { // Just trace functions
+ return new InsertTraceCode(false, true);
+}
-#undef DONT_EMBED_STRINGS_IN_FMT
+Pass *createTraceValuesPassForBasicBlocks() { // Trace BB's and functions
+ return new InsertTraceCode(true, true);
+}
-//************************** 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;
-
- if (lastModule != module)
- { // Let's make sure we create separate global references in each module
- stringRefCache.clear();
- lastModule = module;
- }
-
- 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;
- }
-
- return result;
+
+// Add a prototype for printf if it is not already in the program.
+//
+bool InsertTraceCode::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);
+ return false;
}
-#endif USE_PTRREF
-static inline GlobalVariable*
-GetStringRef(Module* module, const char* str)
-{
- static hash_map<string, GlobalVariable*> stringRefCache;
- static Module* lastModule = NULL;
-
- if (lastModule != module)
- { // Let's make sure we create separate global references in each module
- stringRefCache.clear();
- lastModule = module;
- }
-
- 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;
- }
-
- return result;
+
+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)
-{
+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 || isa<PointerType>(V->getType()))
+ return "0x%p";
+ else if (V->getType()->isIntegral() || V->getType() == Type::BoolTy)
+ return "%d";
+
+ assert(0 && "Illegal value to print out...");
+ return "";
+}
+
+
+static void InsertPrintInst(Value *V, BasicBlock *BB, BasicBlock::iterator &BBI,
+ string Message, Function *Printf) {
+ // 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,ConstantUInt::get(Type::UIntTy, 0)),
+ "trstr");
+ BBI = BB->getInstList().insert(BBI, GEP)+1;
+
+ // Insert the first print instruction to print the string flag:
+ vector<Value*> PrintArgs;
+ PrintArgs.push_back(GEP);
+ if (V) PrintArgs.push_back(V);
+ Instruction *I = new CallInst(Printf, PrintArgs, "trace");
+ BBI = BB->getInstList().insert(BBI, I)+1;
+}
+
+
+static void InsertVerbosePrintInst(Value *V, BasicBlock *BB,
+ BasicBlock::iterator &BBI,
+ const string &Message, Function *Printf) {
+ std::ostringstream OutStr;
+ if (V) WriteAsOperand(OutStr, V);
+ InsertPrintInst(V, BB, BBI, Message+OutStr.str()+" = ", Printf);
}
-//
// 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.
+// for each value in valueVec[] that is live at the end of that basic block,
+// or that is stored to memory in this basic block.
+// If the value is stored to memory, we load it back before printing
+// 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).
+// *bb must be 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
+static void TraceValuesAtBBExit(BasicBlock *BB, Function *Printf,
+ vector<Instruction*> *valuesStoredInFunction) {
+ // Get an iterator to point to the insertion location, which is
+ // just before the terminator instruction.
//
- 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);
+ BasicBlock::iterator InsertPos = BB->end()-1;
+ assert((*InsertPos)->isTerminator());
+ // If the terminator is a conditional branch, insert the trace code just
+ // before the instruction that computes the branch condition (just to
+ // avoid putting a call between the CC-setting instruction and the branch).
+ // Use laterInstrSet to mark instructions that come after the setCC instr
+ // because those cannot be traced at the location we choose.
+ //
+ Instruction *SetCC = 0;
+ if (BranchInst *Branch = dyn_cast<BranchInst>(BB->getTerminator()))
+ if (!Branch->isUnconditional())
+ if (Instruction *I = dyn_cast<Instruction>(Branch->getCondition()))
+ if (I->getParent() == BB) {
+ SetCC = I;
+ while (*InsertPos != SetCC)
+ --InsertPos; // Back up until we can insert before the setcc
+ }
+
+ // Copy all of the instructions into a vector to avoid problems with Setcc
+ const vector<Instruction*> Insts(BB->begin(), InsertPos);
+
+ std::ostringstream OutStr;
+ WriteAsOperand(OutStr, BB, false);
+ InsertPrintInst(0, BB, InsertPos, "LEAVING BB:" + OutStr.str(), Printf);
+
// 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);
+ for (vector<Instruction*>::const_iterator II = Insts.begin(),
+ IE = Insts.end(); II != IE; ++II) {
+ Instruction *I = *II;
+ if (StoreInst *SI = dyn_cast<StoreInst>(I)) {
+ assert(valuesStoredInFunction &&
+ "Should not be printing a store instruction at function exit");
+ LoadInst *LI = new LoadInst(SI->getPointerOperand(), SI->copyIndices(),
+ "reload");
+ InsertPos = BB->getInstList().insert(InsertPos, LI) + 1;
+ valuesStoredInFunction->push_back(LI);
}
+ if (ShouldTraceValue(I))
+ InsertVerbosePrintInst(I, BB, InsertPos, " ", Printf);
+ }
}
-static void
-InsertCodeToShowMethodEntry(BasicBlock* entryBB)
-{
-}
+static inline void InsertCodeToShowFunctionEntry(Function *M, Function *Printf){
+ // Get an iterator to point to the insertion location
+ BasicBlock *BB = M->getEntryNode();
+ BasicBlock::iterator BBI = BB->begin();
-static void
-InsertCodeToShowMethodExit(BasicBlock* exitBB)
-{
-}
+ std::ostringstream OutStr;
+ WriteAsOperand(OutStr, M, true);
+ InsertPrintInst(0, BB, BBI, "ENTERING FUNCTION: " + OutStr.str(), Printf);
+ // Now print all the incoming arguments
+ const Function::ArgumentListType &argList = M->getArgumentList();
+ unsigned ArgNo = 0;
+ for (Function::ArgumentListType::const_iterator
+ I = argList.begin(), E = argList.end(); I != E; ++I, ++ArgNo) {
+ InsertVerbosePrintInst((Value*)*I, BB, BBI,
+ " Arg #" + utostr(ArgNo), Printf);
+ }
+}
-//************************** External Functions ****************************/
-//
-// 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
- }
-
- SymbolTable* symtab = module->getSymbolTable();
- argTypesVec[LASTARGINDEX] = valueType;
- MethodType* printMethodTy = MethodType::get(Type::IntTy, argTypesVec,
- /*isVarArg*/ false);
+static inline void InsertCodeToShowFunctionExit(BasicBlock *BB,
+ Function *Printf) {
+ // Get an iterator to point to the insertion location
+ BasicBlock::iterator BBI = BB->end()-1;
+ ReturnInst *Ret = cast<ReturnInst>(*BBI);
- 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->getParent(), true);
+ InsertPrintInst(0, BB, BBI, "LEAVING FUNCTION: " + OutStr.str(), Printf);
- return printMethod;
+ // print the return value, if any
+ if (BB->getParent()->getReturnType() != Type::VoidTy)
+ InsertPrintInst(Ret->getReturnValue(), BB, BBI, " Returning: ", Printf);
}
-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
-
- free(fmtString.str());
- free(scopeNameString.str());
- free(valNameString.str());
-
- return new CallInst(printMethod, paramList);
-}
+bool InsertTraceCode::doit(Function *M, bool traceBasicBlockExits,
+ bool traceFunctionEvents, Function *Printf) {
+ if (!traceBasicBlockExits && !traceFunctionEvents)
+ return false;
+ vector<Instruction*> valuesStoredInFunction;
+ vector<BasicBlock*> exitBlocks;
-void
-InsertCodeToTraceValues(Method* method,
- bool traceBasicBlockExits,
- bool traceMethodExits)
-{
- vector<Value*> valuesToTraceInMethod;
- Module* module = method->getParent();
- BasicBlock* exitBB = NULL;
-
- if (method->isExternal() ||
- (! traceBasicBlockExits && ! traceMethodExits))
- return;
+ if (traceFunctionEvents)
+ InsertCodeToShowFunctionEntry(M, Printf);
- if (traceMethodExits)
- {
- InsertCodeToShowMethodEntry(method->getEntryNode());
-#ifdef TODO_LATER
- exitBB = method->getExitNode();
+ for (Function::iterator BI = M->begin(); BI != M->end(); ++BI) {
+ BasicBlock *BB = *BI;
+ if (isa<ReturnInst>(BB->getTerminator()))
+ exitBlocks.push_back(BB); // record this as an exit block
+
+ if (traceBasicBlockExits)
+ TraceValuesAtBBExit(BB, Printf, &valuesStoredInFunction);
+ }
+
+ if (traceFunctionEvents)
+ for (unsigned i=0; i < exitBlocks.size(); ++i) {
+#if 0
+ TraceValuesAtBBExit(valuesStoredInFunction, exitBlocks[i], module,
+ /*indent*/ 0, /*isFunctionExit*/ true,
+ /*valuesStoredInFunction*/ NULL);
#endif
+ InsertCodeToShowFunctionExit(exitBlocks[i], Printf);
}
-
- for (Method::iterator BI = method->begin(); BI != method->end(); ++BI)
- {
- BasicBlock* bb = *BI;
- vector<Value*> valuesToTraceInBB;
- FindValuesToTraceInBB(bb, valuesToTraceInBB);
-
- if (traceBasicBlockExits && bb != exitBB)
- TraceValuesAtBBExit(valuesToTraceInBB, bb, module,
- /*indent*/ 4, /*isMethodExit*/ false);
-
- if (traceMethodExits)
- valuesToTraceInMethod.insert(valuesToTraceInMethod.end(),
- valuesToTraceInBB.begin(),
- valuesToTraceInBB.end());
- }
-
- if (traceMethodExits)
- {
- TraceValuesAtBBExit(valuesToTraceInMethod, exitBB, module,
- /*indent*/ 0, /*isMethodExit*/ true);
- InsertCodeToShowMethodExit(exitBB);
- }
+
+ return true;
}