-// $Id$
-//***************************************************************************
-// 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 method
+// exits.
+//
+//===----------------------------------------------------------------------===//
#include "llvm/Transforms/Instrumentation/TraceValues.h"
#include "llvm/GlobalVariable.h"
-#include "llvm/ConstPoolVals.h"
-#include "llvm/Type.h"
+#include "llvm/ConstantVals.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 <strstream>
#include "llvm/Assembly/Writer.h"
+#include "Support/StringExtras.h"
+#include <sstream>
+using std::vector;
+using std::string;
+// Add a prototype for printf if it is not already in the program.
+//
+bool InsertTraceCode::doInitialization(Module *M) {
+ SymbolTable *ST = M->getSymbolTable();
+ const Type *SBP = PointerType::get(Type::SByteTy);
+ const MethodType *MTy =
+ MethodType::get(Type::IntTy, vector<const Type*>(1, SBP), true);
-const char* const PRINTF = "printVal";
+ if (Value *Meth = ST->lookup(PointerType::get(MTy), "printf")) {
+ PrintfMeth = cast<Method>(Meth);
+ return false;
+ }
+
+ // Create a new method and add it to the module
+ PrintfMeth = new Method(MTy, false, "printf");
+ M->getMethodList().push_back(PrintfMeth);
+ return true;
+}
-static inline GlobalVariable *
-GetStringRef(Module *M, const string &str)
-{
- ConstPoolArray *Init = ConstPoolArray::get(str);
- GlobalVariable *V = new GlobalVariable(Init->getType(), /*Const*/true, Init);
- M->getGlobalList().push_back(V);
- return V;
+static inline GlobalVariable *getStringRef(Module *M, const string &str) {
+ // Create a constant internal string reference...
+ Constant *Init = ConstantArray::get(str);
+ GlobalVariable *GV = new GlobalVariable(Init->getType(), true, true, Init,
+ "trstr");
+ M->getGlobalList().push_back(GV);
+ return GV;
}
-static inline bool
-TraceThisOpCode(unsigned opCode)
-{
+
+//
+// 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 (VoidTy's are already excluded)
//
}
-static void
-FindValuesToTraceInBB(BasicBlock* bb, vector<Value*>& valuesToTraceInBB)
-{
- for (BasicBlock::iterator II = bb->begin(); II != bb->end(); ++II)
- if ((*II)->getType()->isPrimitiveType() &&
- (*II)->getType() != Type::VoidTy &&
- TraceThisOpCode((*II)->getOpcode()))
- {
- valuesToTraceInBB.push_back(*II);
- }
+static bool ShouldTraceValue(const Instruction *I) {
+ return
+ I->getType() != Type::VoidTy && LiveAtBBExit(I) &&
+ TraceThisOpCode(I->getOpcode());
}
-// The invocation should be:
-// call "printf"(fmt, value).
-//
-static Value *GetPrintMethodForType(Module *Mod, const Type *valueType) {
- vector<const Type*> ArgTys;
- ArgTys.reserve(2);
- ArgTys.push_back(PointerType::get(ArrayType::get(Type::UByteTy)));
- ArgTys.push_back(valueType);
-
- MethodType *printMethodTy = MethodType::get(Type::VoidTy, ArgTys,
- /*isVarArg*/ false);
-
- SymbolTable *ST = Mod->getSymbolTableSure();
- if (Value *V = ST->lookup(PointerType::get(printMethodTy), PRINTF))
- return V;
-
- // Create a new method and add it to the module
- Method *M = new Method(printMethodTy, PRINTF);
- Mod->getMethodList().push_back(M);
- return M;
-}
-
-
-static Instruction*
-CreatePrintInstr(Value* val,
- const BasicBlock* bb,
- Module* module,
- unsigned int indent,
- bool isMethodExit)
-{
- strstream scopeNameString;
- const Type* valueType = val->getType();
-
- assert(valueType->isPrimitiveType() &&
- valueType->getPrimitiveID() != Type::VoidTyID &&
- valueType->getPrimitiveID() != Type::TypeTyID &&
- valueType->getPrimitiveID() != Type::LabelTyID &&
- "Unsupported type for printing");
-
- const Value* scopeToUse = (isMethodExit)? (const Value*) bb->getParent()
- : (const Value*) bb;
- WriteAsOperand(scopeNameString, scopeToUse) << " : ";
- WriteAsOperand(scopeNameString, val) << " = "
- << val->getType()->getDescription()
- << ends;
- string fmtString(indent, ' ');
-
- fmtString += " At exit of " + string(isMethodExit ? "Method " : "BB ") +
- scopeNameString.str();
-
- switch(valueType->getPrimitiveID()) {
+static string getPrintfCodeFor(const Value *V) {
+ if (V == 0) return "";
+ switch (V->getType()->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;
+ return "%d";
- case Type::PointerTyID:
- fmtString += " %p\0A";
- break;
+ case Type::FloatTyID: case Type::DoubleTyID:
+ return "%g";
+
+ case Type::LabelTyID: case Type::PointerTyID:
+ return "%p";
default:
- assert(0 && "Should not get here. Check the IF expression above");
- return NULL;
+ assert(0 && "Illegal value to print out...");
+ return "";
}
-
- GlobalVariable *fmtVal = GetStringRef(module, fmtString);
-
- vector<Value*> paramList;
- paramList.push_back(fmtVal);
- paramList.push_back(val);
+}
- return new CallInst(GetPrintMethodForType(module, valueType), paramList);
+
+static void InsertPrintInst(Value *V, BasicBlock *BB, BasicBlock::iterator &BBI,
+ string Message, Method *Printf) {
+ // Escape Message by replacing all % characters with %% chars.
+ unsigned Offset = 0;
+ while ((Offset = Message.find('%', Offset)) != string::npos) {
+ Message.replace(Offset, 2, "%%");
+ 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, Method *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 valuesStoredInMethod
+// for printing at the exit from the method. (Note that in each invocation
+// of the method, 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, Method *Printf,
+ vector<Instruction*> *valuesStoredInMethod) {
+ // 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()-1;
- assert((*here)->isTerminator());
+ 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(valuesStoredInMethod &&
+ "Should not be printing a store instruction at method exit");
+ LoadInst *LI = new LoadInst(SI->getPointerOperand(), SI->copyIndices(),
+ "reload");
+ InsertPos = BB->getInstList().insert(InsertPos, LI) + 1;
+ valuesStoredInMethod->push_back(LI);
}
+ if (ShouldTraceValue(I))
+ InsertVerbosePrintInst(I, BB, InsertPos, " ", Printf);
+ }
}
-static void
-InsertCodeToShowMethodEntry(BasicBlock* entryBB)
-{
-}
+static inline void InsertCodeToShowMethodEntry(Method *M, Method *Printf) {
+ // Get an iterator to point to the insertion location
+ BasicBlock *BB = M->getEntryNode();
+ BasicBlock::iterator BBI = BB->begin();
+
+ std::ostringstream OutStr;
+ WriteAsOperand(OutStr, M, true);
+ InsertPrintInst(0, BB, BBI, "ENTERING METHOD: " + OutStr.str(), Printf);
-static void
-InsertCodeToShowMethodExit(BasicBlock* exitBB)
-{
+ // Now print all the incoming arguments
+ const Method::ArgumentListType &argList = M->getArgumentList();
+ unsigned ArgNo = 0;
+ for (Method::ArgumentListType::const_iterator
+ I = argList.begin(), E = argList.end(); I != E; ++I, ++ArgNo) {
+ InsertVerbosePrintInst(*I, BB, BBI,
+ " Arg #" + utostr(ArgNo), Printf);
+ }
}
-bool InsertTraceCode::doInsertTraceCode(Method *M, bool traceBasicBlockExits,
- bool traceMethodExits) {
- vector<Value*> valuesToTraceInMethod;
- Module* module = M->getParent();
- BasicBlock* exitBB = NULL;
+static inline void InsertCodeToShowMethodExit(BasicBlock *BB, Method *Printf) {
+ // Get an iterator to point to the insertion location
+ BasicBlock::iterator BBI = BB->end()-1;
+ ReturnInst *Ret = cast<ReturnInst>(*BBI);
- if (M->isExternal() ||
- (! traceBasicBlockExits && ! traceMethodExits))
- return false;
-
- if (traceMethodExits) {
- InsertCodeToShowMethodEntry(M->getEntryNode());
- exitBB = M->getBasicBlocks().front(); //getExitNode();
- }
+ std::ostringstream OutStr;
+ WriteAsOperand(OutStr, BB->getParent(), true);
+ InsertPrintInst(0, BB, BBI, "LEAVING METHOD: " + OutStr.str(), Printf);
+
+ // print the return value, if any
+ if (BB->getParent()->getReturnType() != Type::VoidTy)
+ InsertPrintInst(Ret->getReturnValue(), BB, BBI, " Returning: ", Printf);
+}
- for (Method::iterator BI = M->begin(); BI != M->end(); ++BI) {
- BasicBlock* bb = *BI;
- vector<Value*> valuesToTraceInBB;
- FindValuesToTraceInBB(bb, valuesToTraceInBB);
+bool InsertTraceCode::doit(Method *M, bool traceBasicBlockExits,
+ bool traceMethodEvents, Method *Printf) {
+ if (!traceBasicBlockExits && !traceMethodEvents)
+ return false;
- if (traceBasicBlockExits && bb != exitBB)
- TraceValuesAtBBExit(valuesToTraceInBB, bb, module,
- /*indent*/ 4, /*isMethodExit*/ false);
+ vector<Instruction*> valuesStoredInMethod;
+ vector<BasicBlock*> exitBlocks;
- if (traceMethodExits) {
- valuesToTraceInMethod.insert(valuesToTraceInMethod.end(),
- valuesToTraceInBB.begin(),
- valuesToTraceInBB.end());
- }
- }
+ if (traceMethodEvents)
+ InsertCodeToShowMethodEntry(M, Printf);
- if (traceMethodExits) {
- TraceValuesAtBBExit(valuesToTraceInMethod, exitBB, module,
- /*indent*/ 0, /*isMethodExit*/ true);
- InsertCodeToShowMethodExit(exitBB);
+ for (Method::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, &valuesStoredInMethod);
}
+
+ if (traceMethodEvents)
+ for (unsigned i=0; i < exitBlocks.size(); ++i) {
+#if 0
+ TraceValuesAtBBExit(valuesStoredInMethod, exitBlocks[i], module,
+ /*indent*/ 0, /*isMethodExit*/ true,
+ /*valuesStoredInMethod*/ NULL);
+#endif
+ InsertCodeToShowMethodExit(exitBlocks[i], Printf);
+ }
+
return true;
}