//===- Local.cpp - Compute a local data structure graph for a function ----===//
+//
+// 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.
+//
+//===----------------------------------------------------------------------===//
//
// Compute the local version of the data structure graph for a function. The
// external interface to this file is the DSGraph constructor.
//
//===----------------------------------------------------------------------===//
-#include "llvm/Analysis/DataStructure.h"
-#include "llvm/Analysis/DSGraph.h"
+#include "llvm/Analysis/DataStructure/DataStructure.h"
+#include "llvm/Analysis/DataStructure/DSGraph.h"
#include "llvm/Constants.h"
#include "llvm/DerivedTypes.h"
-#include "llvm/Function.h"
-#include "llvm/GlobalVariable.h"
#include "llvm/Instructions.h"
+#include "llvm/Intrinsics.h"
+#include "llvm/Support/GetElementPtrTypeIterator.h"
#include "llvm/Support/InstVisitor.h"
#include "llvm/Target/TargetData.h"
#include "Support/CommandLine.h"
//
#include "llvm/Module.h"
+using namespace llvm;
+
static RegisterAnalysis<LocalDataStructures>
X("datastructure", "Local Data Structure Analysis");
-namespace DS {
- // FIXME: Do something smarter with target data!
- TargetData TD("temp-td");
+static cl::opt<bool>
+TrackIntegersAsPointers("dsa-track-integers", cl::Hidden,
+ cl::desc("If this is set, track integers as potential pointers"));
+namespace llvm {
+namespace DS {
// isPointerType - Return true if this type is big enough to hold a pointer.
bool isPointerType(const Type *Ty) {
if (isa<PointerType>(Ty))
return true;
- else if (Ty->isPrimitiveType() && Ty->isInteger())
+ else if (TrackIntegersAsPointers && Ty->isPrimitiveType() &&Ty->isInteger())
return Ty->getPrimitiveSize() >= PointerSize;
return false;
}
-}
-using namespace DS;
+}}
+using namespace DS;
namespace {
cl::opt<bool>
/// graph by performing a single pass over the function in question.
///
class GraphBuilder : InstVisitor<GraphBuilder> {
- Function &F;
DSGraph &G;
- DSNodeHandle &RetNode; // Node that gets returned...
- DSGraph::ScalarMapTy &ScalarMap;
- std::vector<DSCallSite> &FunctionCalls;
+ DSNodeHandle *RetNode; // Node that gets returned...
+ DSScalarMap &ScalarMap;
+ std::vector<DSCallSite> *FunctionCalls;
public:
GraphBuilder(Function &f, DSGraph &g, DSNodeHandle &retNode,
- DSGraph::ScalarMapTy &SM, std::vector<DSCallSite> &fc)
- : F(f), G(g), RetNode(retNode), ScalarMap(SM),
- FunctionCalls(fc) {
+ std::vector<DSCallSite> &fc)
+ : G(g), RetNode(&retNode), ScalarMap(G.getScalarMap()),
+ FunctionCalls(&fc) {
// Create scalar nodes for all pointer arguments...
- for (Function::aiterator I = F.abegin(), E = F.aend(); I != E; ++I)
+ for (Function::aiterator I = f.abegin(), E = f.aend(); I != E; ++I)
if (isPointerType(I->getType()))
getValueDest(*I);
- visit(F); // Single pass over the function
+ visit(f); // Single pass over the function
}
+ // GraphBuilder ctor for working on the globals graph
+ GraphBuilder(DSGraph &g)
+ : G(g), RetNode(0), ScalarMap(G.getScalarMap()), FunctionCalls(0) {
+ }
+
+ void mergeInGlobalInitializer(GlobalVariable *GV);
+
private:
// Visitor functions, used to handle each instruction type we encounter...
friend class InstVisitor<GraphBuilder>;
void visitInstruction(Instruction &I);
void visitCallSite(CallSite CS);
+ void visitVANextInst(VANextInst &I);
+ void visitVAArgInst(VAArgInst &I);
+
+ void MergeConstantInitIntoNode(DSNodeHandle &NH, Constant *C);
private:
// Helper functions used to implement the visitation functions...
DSNode *createNode(const Type *Ty = 0) {
DSNode *N = new DSNode(Ty, &G); // Create the node
if (DisableFieldSensitivity) {
+ // Create node handle referring to the old node so that it is
+ // immediately removed from the graph when the node handle is destroyed.
+ DSNodeHandle OldNNH = N;
N->foldNodeCompletely();
if (DSNode *FN = N->getForwardNode())
N = FN;
};
}
+using namespace DS;
+
//===----------------------------------------------------------------------===//
// DSGraph constructor - Simply use the GraphBuilder to construct the local
// graph.
-DSGraph::DSGraph(Function &F, DSGraph *GG) : GlobalsGraph(GG) {
+DSGraph::DSGraph(const TargetData &td, Function &F, DSGraph *GG)
+ : GlobalsGraph(GG), TD(td) {
PrintAuxCalls = false;
DEBUG(std::cerr << " [Loc] Calculating graph for: " << F.getName() << "\n");
// Use the graph builder to construct the local version of the graph
- GraphBuilder B(F, *this, ReturnNodes[&F], ScalarMap, FunctionCalls);
+ GraphBuilder B(F, *this, ReturnNodes[&F], FunctionCalls);
#ifndef NDEBUG
Timer::addPeakMemoryMeasurement();
#endif
// Remove all integral constants from the scalarmap!
- for (ScalarMapTy::iterator I = ScalarMap.begin(); I != ScalarMap.end();)
- if (isa<ConstantIntegral>(I->first)) {
- ScalarMapTy::iterator J = I++;
- ScalarMap.erase(J);
- } else
+ for (DSScalarMap::iterator I = ScalarMap.begin(); I != ScalarMap.end();)
+ if (isa<ConstantIntegral>(I->first))
+ ScalarMap.erase(I++);
+ else
++I;
+ // If there are any constant globals referenced in this function, merge their
+ // initializers into the local graph from the globals graph.
+ if (ScalarMap.global_begin() != ScalarMap.global_end()) {
+ ReachabilityCloner RC(*this, *GG, 0);
+
+ for (DSScalarMap::global_iterator I = ScalarMap.global_begin();
+ I != ScalarMap.global_end(); ++I)
+ if (GlobalVariable *GV = dyn_cast<GlobalVariable>(*I))
+ if (!GV->isExternal() && GV->isConstant())
+ RC.merge(ScalarMap[GV], GG->ScalarMap[GV]);
+ }
+
markIncompleteNodes(DSGraph::MarkFormalArgs);
// Remove any nodes made dead due to merging...
// Otherwise we need to create a new node to point to.
// Check first for constant expressions that must be traversed to
// extract the actual value.
- if (Constant *C = dyn_cast<Constant>(V))
- if (ConstantPointerRef *CPR = dyn_cast<ConstantPointerRef>(C)) {
- return NH = getValueDest(*CPR->getValue());
- } else if (ConstantExpr *CE = dyn_cast<ConstantExpr>(C)) {
+ DSNode* N;
+ if (GlobalValue* GV = dyn_cast<GlobalValue>(V)) {
+ // Create a new global node for this global variable...
+ N = createNode(GV->getType()->getElementType());
+ N->addGlobal(GV);
+ } else if (Constant *C = dyn_cast<Constant>(V)) {
+ if (ConstantExpr *CE = dyn_cast<ConstantExpr>(C)) {
if (CE->getOpcode() == Instruction::Cast)
NH = getValueDest(*CE->getOperand(0));
else if (CE->getOpcode() == Instruction::GetElementPtr) {
visitGetElementPtrInst(*CE);
- DSGraph::ScalarMapTy::iterator I = ScalarMap.find(CE);
+ DSScalarMap::iterator I = ScalarMap.find(CE);
assert(I != ScalarMap.end() && "GEP didn't get processed right?");
NH = I->second;
} else {
} else {
assert(0 && "Unknown constant type!");
}
-
- // Otherwise we need to create a new node to point to...
- DSNode *N;
- if (GlobalValue *GV = dyn_cast<GlobalValue>(V)) {
- // Create a new global node for this global variable...
- N = createNode(GV->getType()->getElementType());
- N->addGlobal(GV);
+ N = createNode(); // just create a shadow node
} else {
// Otherwise just create a shadow node
N = createNode();
}
- NH.setNode(N); // Remember that we are pointing to it...
- NH.setOffset(0);
+ NH.setTo(N, 0); // Remember that we are pointing to it...
return NH;
}
/// merge the two destinations together.
///
void GraphBuilder::setDestTo(Value &V, const DSNodeHandle &NH) {
- DSNodeHandle &AINH = ScalarMap[&V];
- if (AINH.getNode() == 0) // Not pointing to anything yet?
- AINH = NH; // Just point directly to NH
- else
- AINH.mergeWith(NH);
+ ScalarMap[&V].mergeWith(NH);
}
DSNodeHandle Value = getValueDest(*GEP.getOperand(0));
if (Value.getNode() == 0) return;
- unsigned Offset = 0;
+ // As a special case, if all of the index operands of GEP are constant zeros,
+ // handle this just like we handle casts (ie, don't do much).
+ bool AllZeros = true;
+ for (unsigned i = 1, e = GEP.getNumOperands(); i != e; ++i)
+ if (GEP.getOperand(i) !=
+ Constant::getNullValue(GEP.getOperand(i)->getType())) {
+ AllZeros = false;
+ break;
+ }
+
+ // If all of the indices are zero, the result points to the operand without
+ // applying the type.
+ if (AllZeros) {
+ setDestTo(GEP, Value);
+ return;
+ }
+
+
const PointerType *PTy = cast<PointerType>(GEP.getOperand(0)->getType());
const Type *CurTy = PTy->getElementType();
return;
}
+ const TargetData &TD = Value.getNode()->getTargetData();
+
#if 0
// Handle the pointer index specially...
if (GEP.getNumOperands() > 1 &&
- GEP.getOperand(1) != ConstantSInt::getNullValue(Type::LongTy)) {
+ (!isa<Constant>(GEP.getOperand(1)) ||
+ !cast<Constant>(GEP.getOperand(1))->isNullValue())) {
// If we already know this is an array being accessed, don't do anything...
if (!TopTypeRec.isArray) {
#endif
// All of these subscripts are indexing INTO the elements we have...
- for (unsigned i = 2, e = GEP.getNumOperands(); i < e; ++i)
- if (GEP.getOperand(i)->getType() == Type::LongTy) {
- // Get the type indexing into...
- const SequentialType *STy = cast<SequentialType>(CurTy);
- CurTy = STy->getElementType();
+ unsigned Offset = 0;
+ for (gep_type_iterator I = gep_type_begin(GEP), E = gep_type_end(GEP);
+ I != E; ++I)
+ if (const StructType *STy = dyn_cast<StructType>(*I)) {
+ unsigned FieldNo = cast<ConstantUInt>(I.getOperand())->getValue();
+ Offset += TD.getStructLayout(STy)->MemberOffsets[FieldNo];
+ } else if (const PointerType *PTy = dyn_cast<PointerType>(*I)) {
+ if (!isa<Constant>(I.getOperand()) ||
+ !cast<Constant>(I.getOperand())->isNullValue())
+ Value.getNode()->setArrayMarker();
+ }
+
+
#if 0
+ if (const SequentialType *STy = cast<SequentialType>(*I)) {
+ CurTy = STy->getElementType();
if (ConstantSInt *CS = dyn_cast<ConstantSInt>(GEP.getOperand(i))) {
Offset += CS->getValue()*TD.getTypeSize(CurTy);
} else {
N->mergeIndexes(RawOffset+j, RawOffset+i*ElSize+j);
}
}
-#endif
- } else if (GEP.getOperand(i)->getType() == Type::UByteTy) {
- unsigned FieldNo = cast<ConstantUInt>(GEP.getOperand(i))->getValue();
- const StructType *STy = cast<StructType>(CurTy);
- Offset += TD.getStructLayout(STy)->MemberOffsets[FieldNo];
- CurTy = STy->getContainedType(FieldNo);
}
+#endif
// Add in the offset calculated...
Value.setOffset(Value.getOffset()+Offset);
void GraphBuilder::visitStoreInst(StoreInst &SI) {
const Type *StoredTy = SI.getOperand(0)->getType();
DSNodeHandle Dest = getValueDest(*SI.getOperand(1));
- if (Dest.getNode() == 0) return;
+ if (Dest.isNull()) return;
// Mark that the node is written to...
Dest.getNode()->setModifiedMarker();
- // Ensure a typerecord exists...
+ // Ensure a type-record exists...
Dest.getNode()->mergeTypeInfo(StoredTy, Dest.getOffset());
// Avoid adding edges from null, or processing non-"pointer" stores
void GraphBuilder::visitReturnInst(ReturnInst &RI) {
if (RI.getNumOperands() && isPointerType(RI.getOperand(0)->getType()))
- RetNode.mergeWith(getValueDest(*RI.getOperand(0)));
+ RetNode->mergeWith(getValueDest(*RI.getOperand(0)));
+}
+
+void GraphBuilder::visitVANextInst(VANextInst &I) {
+ getValueDest(*I.getOperand(0)).mergeWith(getValueDest(I));
+}
+
+void GraphBuilder::visitVAArgInst(VAArgInst &I) {
+ DSNodeHandle Ptr = getValueDest(*I.getOperand(0));
+ if (Ptr.isNull()) return;
+
+ // Make that the node is read from.
+ Ptr.getNode()->setReadMarker();
+
+ // Ensure a typerecord exists...
+ Ptr.getNode()->mergeTypeInfo(I.getType(), Ptr.getOffset(), false);
+
+ if (isPointerType(I.getType()))
+ setDestTo(I, getLink(Ptr));
}
+
void GraphBuilder::visitCallInst(CallInst &CI) {
visitCallSite(&CI);
}
}
void GraphBuilder::visitCallSite(CallSite CS) {
+ Value *Callee = CS.getCalledValue();
+
+ // Special case handling of certain libc allocation functions here.
+ if (Function *F = dyn_cast<Function>(Callee))
+ if (F->isExternal())
+ switch (F->getIntrinsicID()) {
+ case Intrinsic::vastart:
+ getValueDest(*CS.getInstruction()).getNode()->setAllocaNodeMarker();
+ return;
+ case Intrinsic::vacopy:
+ getValueDest(*CS.getInstruction()).
+ mergeWith(getValueDest(**(CS.arg_begin())));
+ return;
+ case Intrinsic::vaend:
+ return; // noop
+ case Intrinsic::memmove:
+ case Intrinsic::memcpy: {
+ // Merge the first & second arguments, and mark the memory read and
+ // modified.
+ DSNodeHandle RetNH = getValueDest(**CS.arg_begin());
+ RetNH.mergeWith(getValueDest(**(CS.arg_begin()+1)));
+ if (DSNode *N = RetNH.getNode())
+ N->setModifiedMarker()->setReadMarker();
+ return;
+ }
+ case Intrinsic::memset:
+ // Mark the memory modified.
+ if (DSNode *N = getValueDest(**CS.arg_begin()).getNode())
+ N->setModifiedMarker();
+ return;
+ default:
+ if (F->getName() == "calloc" || F->getName() == "posix_memalign" ||
+ F->getName() == "memalign" || F->getName() == "valloc") {
+ setDestTo(*CS.getInstruction(),
+ createNode()->setHeapNodeMarker()->setModifiedMarker());
+ return;
+ } else if (F->getName() == "realloc") {
+ DSNodeHandle RetNH = getValueDest(*CS.getInstruction());
+ RetNH.mergeWith(getValueDest(**CS.arg_begin()));
+ if (DSNode *N = RetNH.getNode())
+ N->setHeapNodeMarker()->setModifiedMarker()->setReadMarker();
+ return;
+ } else if (F->getName() == "memmove") {
+ // Merge the first & second arguments, and mark the memory read and
+ // modified.
+ DSNodeHandle RetNH = getValueDest(**CS.arg_begin());
+ RetNH.mergeWith(getValueDest(**(CS.arg_begin()+1)));
+ if (DSNode *N = RetNH.getNode())
+ N->setModifiedMarker()->setReadMarker();
+ return;
+
+ } else if (F->getName() == "atoi" || F->getName() == "atof" ||
+ F->getName() == "atol" || F->getName() == "atoll" ||
+ F->getName() == "remove" || F->getName() == "unlink" ||
+ F->getName() == "rename" || F->getName() == "memcmp" ||
+ F->getName() == "strcmp" || F->getName() == "strncmp" ||
+ F->getName() == "execl" || F->getName() == "execlp" ||
+ F->getName() == "execle" || F->getName() == "execv" ||
+ F->getName() == "execvp" || F->getName() == "chmod" ||
+ F->getName() == "puts" || F->getName() == "write" ||
+ F->getName() == "open" || F->getName() == "create" ||
+ F->getName() == "truncate" || F->getName() == "chdir" ||
+ F->getName() == "mkdir" || F->getName() == "rmdir") {
+ // These functions read all of their pointer operands.
+ for (CallSite::arg_iterator AI = CS.arg_begin(), E = CS.arg_end();
+ AI != E; ++AI) {
+ if (isPointerType((*AI)->getType()))
+ if (DSNode *N = getValueDest(**AI).getNode())
+ N->setReadMarker();
+ }
+ return;
+ } else if (F->getName() == "read" || F->getName() == "pipe" ||
+ F->getName() == "wait" || F->getName() == "time") {
+ // These functions write all of their pointer operands.
+ for (CallSite::arg_iterator AI = CS.arg_begin(), E = CS.arg_end();
+ AI != E; ++AI) {
+ if (isPointerType((*AI)->getType()))
+ if (DSNode *N = getValueDest(**AI).getNode())
+ N->setModifiedMarker();
+ }
+ return;
+ } else if (F->getName() == "stat" || F->getName() == "fstat" ||
+ F->getName() == "lstat") {
+ // These functions read their first operand if its a pointer.
+ CallSite::arg_iterator AI = CS.arg_begin();
+ if (isPointerType((*AI)->getType())) {
+ DSNodeHandle Path = getValueDest(**AI);
+ if (DSNode *N = Path.getNode()) N->setReadMarker();
+ }
+
+ // Then they write into the stat buffer.
+ DSNodeHandle StatBuf = getValueDest(**++AI);
+ if (DSNode *N = StatBuf.getNode()) {
+ N->setModifiedMarker();
+ const Type *StatTy = F->getFunctionType()->getParamType(1);
+ if (const PointerType *PTy = dyn_cast<PointerType>(StatTy))
+ N->mergeTypeInfo(PTy->getElementType(), StatBuf.getOffset());
+ }
+ return;
+ } else if (F->getName() == "strtod" || F->getName() == "strtof" ||
+ F->getName() == "strtold") {
+ // These functions read the first pointer
+ if (DSNode *Str = getValueDest(**CS.arg_begin()).getNode()) {
+ Str->setReadMarker();
+ // If the second parameter is passed, it will point to the first
+ // argument node.
+ const DSNodeHandle &EndPtrNH = getValueDest(**(CS.arg_begin()+1));
+ if (DSNode *End = EndPtrNH.getNode()) {
+ End->mergeTypeInfo(PointerType::get(Type::SByteTy),
+ EndPtrNH.getOffset(), false);
+ End->setModifiedMarker();
+ DSNodeHandle &Link = getLink(EndPtrNH);
+ Link.mergeWith(getValueDest(**CS.arg_begin()));
+ }
+ }
+
+ return;
+ } else if (F->getName() == "fopen" || F->getName() == "fdopen" ||
+ F->getName() == "freopen") {
+ // These functions read all of their pointer operands.
+ for (CallSite::arg_iterator AI = CS.arg_begin(), E = CS.arg_end();
+ AI != E; ++AI)
+ if (isPointerType((*AI)->getType()))
+ if (DSNode *N = getValueDest(**AI).getNode())
+ N->setReadMarker();
+
+ // fopen allocates in an unknown way and writes to the file
+ // descriptor. Also, merge the allocated type into the node.
+ DSNodeHandle Result = getValueDest(*CS.getInstruction());
+ if (DSNode *N = Result.getNode()) {
+ N->setModifiedMarker()->setUnknownNodeMarker();
+ const Type *RetTy = F->getFunctionType()->getReturnType();
+ if (const PointerType *PTy = dyn_cast<PointerType>(RetTy))
+ N->mergeTypeInfo(PTy->getElementType(), Result.getOffset());
+ }
+
+ // If this is freopen, merge the file descriptor passed in with the
+ // result.
+ if (F->getName() == "freopen")
+ Result.mergeWith(getValueDest(**--CS.arg_end()));
+
+ return;
+ } else if (F->getName() == "fclose" && CS.arg_end()-CS.arg_begin() ==1){
+ // fclose reads and deallocates the memory in an unknown way for the
+ // file descriptor. It merges the FILE type into the descriptor.
+ DSNodeHandle H = getValueDest(**CS.arg_begin());
+ if (DSNode *N = H.getNode()) {
+ N->setReadMarker()->setUnknownNodeMarker();
+ const Type *ArgTy = F->getFunctionType()->getParamType(0);
+ if (const PointerType *PTy = dyn_cast<PointerType>(ArgTy))
+ N->mergeTypeInfo(PTy->getElementType(), H.getOffset());
+ }
+ return;
+ } else if (CS.arg_end()-CS.arg_begin() == 1 &&
+ (F->getName() == "fflush" || F->getName() == "feof" ||
+ F->getName() == "fileno" || F->getName() == "clearerr" ||
+ F->getName() == "rewind" || F->getName() == "ftell" ||
+ F->getName() == "ferror" || F->getName() == "fgetc" ||
+ F->getName() == "fgetc" || F->getName() == "_IO_getc")) {
+ // fflush reads and writes the memory for the file descriptor. It
+ // merges the FILE type into the descriptor.
+ DSNodeHandle H = getValueDest(**CS.arg_begin());
+ if (DSNode *N = H.getNode()) {
+ N->setReadMarker()->setModifiedMarker();
+
+ const Type *ArgTy = F->getFunctionType()->getParamType(0);
+ if (const PointerType *PTy = dyn_cast<PointerType>(ArgTy))
+ N->mergeTypeInfo(PTy->getElementType(), H.getOffset());
+ }
+ return;
+ } else if (CS.arg_end()-CS.arg_begin() == 4 &&
+ (F->getName() == "fwrite" || F->getName() == "fread")) {
+ // fread writes the first operand, fwrite reads it. They both
+ // read/write the FILE descriptor, and merges the FILE type.
+ DSNodeHandle H = getValueDest(**--CS.arg_end());
+ if (DSNode *N = H.getNode()) {
+ N->setReadMarker()->setModifiedMarker();
+ const Type *ArgTy = F->getFunctionType()->getParamType(3);
+ if (const PointerType *PTy = dyn_cast<PointerType>(ArgTy))
+ N->mergeTypeInfo(PTy->getElementType(), H.getOffset());
+ }
+
+ H = getValueDest(**CS.arg_begin());
+ if (DSNode *N = H.getNode())
+ if (F->getName() == "fwrite")
+ N->setReadMarker();
+ else
+ N->setModifiedMarker();
+ return;
+ } else if (F->getName() == "fgets" && CS.arg_end()-CS.arg_begin() == 3){
+ // fgets reads and writes the memory for the file descriptor. It
+ // merges the FILE type into the descriptor, and writes to the
+ // argument. It returns the argument as well.
+ CallSite::arg_iterator AI = CS.arg_begin();
+ DSNodeHandle H = getValueDest(**AI);
+ if (DSNode *N = H.getNode())
+ N->setModifiedMarker(); // Writes buffer
+ H.mergeWith(getValueDest(*CS.getInstruction())); // Returns buffer
+ ++AI; ++AI;
+
+ // Reads and writes file descriptor, merge in FILE type.
+ H = getValueDest(**AI);
+ if (DSNode *N = H.getNode()) {
+ N->setReadMarker()->setModifiedMarker();
+ const Type *ArgTy = F->getFunctionType()->getParamType(2);
+ if (const PointerType *PTy = dyn_cast<PointerType>(ArgTy))
+ N->mergeTypeInfo(PTy->getElementType(), H.getOffset());
+ }
+ return;
+ } else if (F->getName() == "ungetc" || F->getName() == "fputc" ||
+ F->getName() == "fputs" || F->getName() == "putc" ||
+ F->getName() == "ftell" || F->getName() == "rewind" ||
+ F->getName() == "_IO_putc") {
+ // These functions read and write the memory for the file descriptor,
+ // which is passes as the last argument.
+ DSNodeHandle H = getValueDest(**--CS.arg_end());
+ if (DSNode *N = H.getNode()) {
+ N->setReadMarker()->setModifiedMarker();
+ const Type *ArgTy = *--F->getFunctionType()->param_end();
+ if (const PointerType *PTy = dyn_cast<PointerType>(ArgTy))
+ N->mergeTypeInfo(PTy->getElementType(), H.getOffset());
+ }
+
+ // Any pointer arguments are read.
+ for (CallSite::arg_iterator AI = CS.arg_begin(), E = CS.arg_end();
+ AI != E; ++AI)
+ if (isPointerType((*AI)->getType()))
+ if (DSNode *N = getValueDest(**AI).getNode())
+ N->setReadMarker();
+ return;
+ } else if (F->getName() == "fseek" || F->getName() == "fgetpos" ||
+ F->getName() == "fsetpos") {
+ // These functions read and write the memory for the file descriptor,
+ // and read/write all other arguments.
+ DSNodeHandle H = getValueDest(**CS.arg_begin());
+ if (DSNode *N = H.getNode()) {
+ const Type *ArgTy = *--F->getFunctionType()->param_end();
+ if (const PointerType *PTy = dyn_cast<PointerType>(ArgTy))
+ N->mergeTypeInfo(PTy->getElementType(), H.getOffset());
+ }
+
+ // Any pointer arguments are read.
+ for (CallSite::arg_iterator AI = CS.arg_begin(), E = CS.arg_end();
+ AI != E; ++AI)
+ if (isPointerType((*AI)->getType()))
+ if (DSNode *N = getValueDest(**AI).getNode())
+ N->setReadMarker()->setModifiedMarker();
+ return;
+ } else if (F->getName() == "printf" || F->getName() == "fprintf" ||
+ F->getName() == "sprintf") {
+ CallSite::arg_iterator AI = CS.arg_begin(), E = CS.arg_end();
+
+ if (F->getName() == "fprintf") {
+ // fprintf reads and writes the FILE argument, and applies the type
+ // to it.
+ DSNodeHandle H = getValueDest(**AI);
+ if (DSNode *N = H.getNode()) {
+ N->setModifiedMarker();
+ const Type *ArgTy = (*AI)->getType();
+ if (const PointerType *PTy = dyn_cast<PointerType>(ArgTy))
+ N->mergeTypeInfo(PTy->getElementType(), H.getOffset());
+ }
+ } else if (F->getName() == "sprintf") {
+ // sprintf writes the first string argument.
+ DSNodeHandle H = getValueDest(**AI++);
+ if (DSNode *N = H.getNode()) {
+ N->setModifiedMarker();
+ const Type *ArgTy = (*AI)->getType();
+ if (const PointerType *PTy = dyn_cast<PointerType>(ArgTy))
+ N->mergeTypeInfo(PTy->getElementType(), H.getOffset());
+ }
+ }
+
+ for (; AI != E; ++AI) {
+ // printf reads all pointer arguments.
+ if (isPointerType((*AI)->getType()))
+ if (DSNode *N = getValueDest(**AI).getNode())
+ N->setReadMarker();
+ }
+ return;
+ } else if (F->getName() == "vprintf" || F->getName() == "vfprintf" ||
+ F->getName() == "vsprintf") {
+ CallSite::arg_iterator AI = CS.arg_begin(), E = CS.arg_end();
+
+ if (F->getName() == "vfprintf") {
+ // ffprintf reads and writes the FILE argument, and applies the type
+ // to it.
+ DSNodeHandle H = getValueDest(**AI);
+ if (DSNode *N = H.getNode()) {
+ N->setModifiedMarker()->setReadMarker();
+ const Type *ArgTy = (*AI)->getType();
+ if (const PointerType *PTy = dyn_cast<PointerType>(ArgTy))
+ N->mergeTypeInfo(PTy->getElementType(), H.getOffset());
+ }
+ ++AI;
+ } else if (F->getName() == "vsprintf") {
+ // vsprintf writes the first string argument.
+ DSNodeHandle H = getValueDest(**AI++);
+ if (DSNode *N = H.getNode()) {
+ N->setModifiedMarker();
+ const Type *ArgTy = (*AI)->getType();
+ if (const PointerType *PTy = dyn_cast<PointerType>(ArgTy))
+ N->mergeTypeInfo(PTy->getElementType(), H.getOffset());
+ }
+ }
+
+ // Read the format
+ if (AI != E) {
+ if (isPointerType((*AI)->getType()))
+ if (DSNode *N = getValueDest(**AI).getNode())
+ N->setReadMarker();
+ ++AI;
+ }
+
+ // Read the valist, and the pointed-to objects.
+ if (AI != E && isPointerType((*AI)->getType())) {
+ const DSNodeHandle &VAList = getValueDest(**AI);
+ if (DSNode *N = VAList.getNode()) {
+ N->setReadMarker();
+ N->mergeTypeInfo(PointerType::get(Type::SByteTy),
+ VAList.getOffset(), false);
+
+ DSNodeHandle &VAListObjs = getLink(VAList);
+ VAListObjs.getNode()->setReadMarker();
+ }
+ }
+
+ return;
+ } else if (F->getName() == "scanf" || F->getName() == "fscanf" ||
+ F->getName() == "sscanf") {
+ CallSite::arg_iterator AI = CS.arg_begin(), E = CS.arg_end();
+
+ if (F->getName() == "fscanf") {
+ // fscanf reads and writes the FILE argument, and applies the type
+ // to it.
+ DSNodeHandle H = getValueDest(**AI);
+ if (DSNode *N = H.getNode()) {
+ N->setReadMarker();
+ const Type *ArgTy = (*AI)->getType();
+ if (const PointerType *PTy = dyn_cast<PointerType>(ArgTy))
+ N->mergeTypeInfo(PTy->getElementType(), H.getOffset());
+ }
+ } else if (F->getName() == "sscanf") {
+ // sscanf reads the first string argument.
+ DSNodeHandle H = getValueDest(**AI++);
+ if (DSNode *N = H.getNode()) {
+ N->setReadMarker();
+ const Type *ArgTy = (*AI)->getType();
+ if (const PointerType *PTy = dyn_cast<PointerType>(ArgTy))
+ N->mergeTypeInfo(PTy->getElementType(), H.getOffset());
+ }
+ }
+
+ for (; AI != E; ++AI) {
+ // scanf writes all pointer arguments.
+ if (isPointerType((*AI)->getType()))
+ if (DSNode *N = getValueDest(**AI).getNode())
+ N->setModifiedMarker();
+ }
+ return;
+ } else if (F->getName() == "strtok") {
+ // strtok reads and writes the first argument, returning it. It reads
+ // its second arg. FIXME: strtok also modifies some hidden static
+ // data. Someday this might matter.
+ CallSite::arg_iterator AI = CS.arg_begin();
+ DSNodeHandle H = getValueDest(**AI++);
+ if (DSNode *N = H.getNode()) {
+ N->setReadMarker()->setModifiedMarker(); // Reads/Writes buffer
+ const Type *ArgTy = F->getFunctionType()->getParamType(0);
+ if (const PointerType *PTy = dyn_cast<PointerType>(ArgTy))
+ N->mergeTypeInfo(PTy->getElementType(), H.getOffset());
+ }
+ H.mergeWith(getValueDest(*CS.getInstruction())); // Returns buffer
+
+ H = getValueDest(**AI); // Reads delimiter
+ if (DSNode *N = H.getNode()) {
+ N->setReadMarker();
+ const Type *ArgTy = F->getFunctionType()->getParamType(1);
+ if (const PointerType *PTy = dyn_cast<PointerType>(ArgTy))
+ N->mergeTypeInfo(PTy->getElementType(), H.getOffset());
+ }
+ return;
+ } else if (F->getName() == "strchr" || F->getName() == "strrchr" ||
+ F->getName() == "strstr") {
+ // These read their arguments, and return the first one
+ DSNodeHandle H = getValueDest(**CS.arg_begin());
+ H.mergeWith(getValueDest(*CS.getInstruction())); // Returns buffer
+
+ for (CallSite::arg_iterator AI = CS.arg_begin(), E = CS.arg_end();
+ AI != E; ++AI)
+ if (isPointerType((*AI)->getType()))
+ if (DSNode *N = getValueDest(**AI).getNode())
+ N->setReadMarker();
+
+ if (DSNode *N = H.getNode())
+ N->setReadMarker();
+ return;
+ } else if (F->getName() == "modf" && CS.arg_end()-CS.arg_begin() == 2) {
+ // This writes its second argument, and forces it to double.
+ DSNodeHandle H = getValueDest(**--CS.arg_end());
+ if (DSNode *N = H.getNode()) {
+ N->setModifiedMarker();
+ N->mergeTypeInfo(Type::DoubleTy, H.getOffset());
+ }
+ return;
+ } else {
+ // Unknown function, warn if it returns a pointer type or takes a
+ // pointer argument.
+ bool Warn = isPointerType(CS.getInstruction()->getType());
+ if (!Warn)
+ for (CallSite::arg_iterator I = CS.arg_begin(), E = CS.arg_end();
+ I != E; ++I)
+ if (isPointerType((*I)->getType())) {
+ Warn = true;
+ break;
+ }
+ if (Warn)
+ std::cerr << "WARNING: Call to unknown external function '"
+ << F->getName() << "' will cause pessimistic results!\n";
+ }
+ }
+
+
// Set up the return value...
DSNodeHandle RetVal;
Instruction *I = CS.getInstruction();
if (isPointerType(I->getType()))
RetVal = getValueDest(*I);
- DSNode *Callee = 0;
- if (DisableDirectCallOpt || !isa<Function>(CS.getCalledValue()))
- Callee = getValueDest(*CS.getCalledValue()).getNode();
+ DSNode *CalleeNode = 0;
+ if (DisableDirectCallOpt || !isa<Function>(Callee)) {
+ CalleeNode = getValueDest(*Callee).getNode();
+ if (CalleeNode == 0) {
+ std::cerr << "WARNING: Program is calling through a null pointer?\n"<< *I;
+ return; // Calling a null pointer?
+ }
+ }
std::vector<DSNodeHandle> Args;
Args.reserve(CS.arg_end()-CS.arg_begin());
Args.push_back(getValueDest(**I));
// Add a new function call entry...
- if (Callee)
- FunctionCalls.push_back(DSCallSite(CS, RetVal, Callee, Args));
+ if (CalleeNode)
+ FunctionCalls->push_back(DSCallSite(CS, RetVal, CalleeNode, Args));
else
- FunctionCalls.push_back(DSCallSite(CS, RetVal, CS.getCalledFunction(),
- Args));
+ FunctionCalls->push_back(DSCallSite(CS, RetVal, cast<Function>(Callee),
+ Args));
}
void GraphBuilder::visitFreeInst(FreeInst &FI) {
// Mark that the node is written to...
- DSNode *N = getValueDest(*FI.getOperand(0)).getNode();
- N->setModifiedMarker();
- N->setHeapNodeMarker();
+ if (DSNode *N = getValueDest(*FI.getOperand(0)).getNode())
+ N->setModifiedMarker()->setHeapNodeMarker();
}
/// Handle casts...
// LocalDataStructures Implementation
//===----------------------------------------------------------------------===//
+// MergeConstantInitIntoNode - Merge the specified constant into the node
+// pointed to by NH.
+void GraphBuilder::MergeConstantInitIntoNode(DSNodeHandle &NH, Constant *C) {
+ // Ensure a type-record exists...
+ NH.getNode()->mergeTypeInfo(C->getType(), NH.getOffset());
+
+ if (C->getType()->isFirstClassType()) {
+ if (isPointerType(C->getType()))
+ // Avoid adding edges from null, or processing non-"pointer" stores
+ NH.addEdgeTo(getValueDest(*C));
+ return;
+ }
+
+ const TargetData &TD = NH.getNode()->getTargetData();
+
+ if (ConstantArray *CA = dyn_cast<ConstantArray>(C)) {
+ for (unsigned i = 0, e = CA->getNumOperands(); i != e; ++i)
+ // We don't currently do any indexing for arrays...
+ MergeConstantInitIntoNode(NH, cast<Constant>(CA->getOperand(i)));
+ } else if (ConstantStruct *CS = dyn_cast<ConstantStruct>(C)) {
+ const StructLayout *SL = TD.getStructLayout(CS->getType());
+ for (unsigned i = 0, e = CS->getNumOperands(); i != e; ++i) {
+ DSNodeHandle NewNH(NH.getNode(), NH.getOffset()+SL->MemberOffsets[i]);
+ MergeConstantInitIntoNode(NewNH, cast<Constant>(CS->getOperand(i)));
+ }
+ } else if (ConstantAggregateZero *CAZ = dyn_cast<ConstantAggregateZero>(C)) {
+ // Noop
+ } else {
+ assert(0 && "Unknown constant type!");
+ }
+}
+
+void GraphBuilder::mergeInGlobalInitializer(GlobalVariable *GV) {
+ assert(!GV->isExternal() && "Cannot merge in external global!");
+ // Get a node handle to the global node and merge the initializer into it.
+ DSNodeHandle NH = getValueDest(*GV);
+ MergeConstantInitIntoNode(NH, GV->getInitializer());
+}
+
+
bool LocalDataStructures::run(Module &M) {
- GlobalsGraph = new DSGraph();
+ GlobalsGraph = new DSGraph(getAnalysis<TargetData>());
+
+ const TargetData &TD = getAnalysis<TargetData>();
+
+ {
+ GraphBuilder GGB(*GlobalsGraph);
+
+ // Add initializers for all of the globals to the globals graph...
+ for (Module::giterator I = M.gbegin(), E = M.gend(); I != E; ++I)
+ if (!I->isExternal())
+ GGB.mergeInGlobalInitializer(I);
+ }
// Calculate all of the graphs...
for (Module::iterator I = M.begin(), E = M.end(); I != E; ++I)
if (!I->isExternal())
- DSInfo.insert(std::make_pair(I, new DSGraph(*I, GlobalsGraph)));
+ DSInfo.insert(std::make_pair(I, new DSGraph(TD, *I, GlobalsGraph)));
+
+ GlobalsGraph->removeTriviallyDeadNodes();
+ GlobalsGraph->markIncompleteNodes(DSGraph::MarkFormalArgs);
return false;
}
delete GlobalsGraph;
GlobalsGraph = 0;
}
+
projects / oota-llvm.git / blobdiff