//===- 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/DSGraph.h"
#include "llvm/Analysis/DataStructure.h"
-#include "llvm/iMemory.h"
-#include "llvm/iTerminators.h"
-#include "llvm/iPHINode.h"
-#include "llvm/iOther.h"
+#include "llvm/Analysis/DSGraph.h"
#include "llvm/Constants.h"
#include "llvm/DerivedTypes.h"
-#include "llvm/Function.h"
-#include "llvm/GlobalVariable.h"
+#include "llvm/Instructions.h"
+#include "llvm/Support/GetElementPtrTypeIterator.h"
#include "llvm/Support/InstVisitor.h"
#include "llvm/Target/TargetData.h"
-#include "Support/Statistic.h"
+#include "Support/CommandLine.h"
+#include "Support/Debug.h"
+#include "Support/Timer.h"
// FIXME: This should eventually be a FunctionPass that is automatically
// aggregated into a Pass.
//
#include "llvm/Module.h"
-using std::map;
-using std::vector;
+using namespace llvm;
static RegisterAnalysis<LocalDataStructures>
X("datastructure", "Local Data Structure Analysis");
-using namespace DataStructureAnalysis;
-
-namespace DataStructureAnalysis {
- // FIXME: Do something smarter with target data!
- TargetData TD("temp-td");
- unsigned PointerSize(TD.getPointerSize());
+static cl::opt<bool>
+TrackIntegersAsPointers("dsa-track-integers",
+ 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;
namespace {
+ cl::opt<bool>
+ DisableDirectCallOpt("disable-direct-call-dsopt", cl::Hidden,
+ cl::desc("Disable direct call optimization in "
+ "DSGraph construction"));
+ cl::opt<bool>
+ DisableFieldSensitivity("disable-ds-field-sensitivity", cl::Hidden,
+ cl::desc("Disable field sensitivity in DSGraphs"));
+
//===--------------------------------------------------------------------===//
// GraphBuilder Class
//===--------------------------------------------------------------------===//
///
class GraphBuilder : InstVisitor<GraphBuilder> {
DSGraph &G;
- vector<DSNode*> &Nodes;
- DSNodeHandle &RetNode; // Node that gets returned...
- map<Value*, DSNodeHandle> &ValueMap;
- vector<DSCallSite> &FunctionCalls;
+ DSNodeHandle *RetNode; // Node that gets returned...
+ DSGraph::ScalarMapTy &ScalarMap;
+ std::vector<DSCallSite> *FunctionCalls;
public:
- GraphBuilder(DSGraph &g, vector<DSNode*> &nodes, DSNodeHandle &retNode,
- map<Value*, DSNodeHandle> &vm,
- vector<DSCallSite> &fc)
- : G(g), Nodes(nodes), RetNode(retNode), ValueMap(vm), FunctionCalls(fc) {
+ GraphBuilder(Function &f, DSGraph &g, DSNodeHandle &retNode,
+ std::vector<DSCallSite> &fc)
+ : G(g), RetNode(&retNode), ScalarMap(G.getScalarMap()),
+ FunctionCalls(&fc) {
// Create scalar nodes for all pointer arguments...
- for (Function::aiterator I = G.getFunction().abegin(),
- E = G.getFunction().aend(); I != E; ++I)
+ for (Function::aiterator I = f.abegin(), E = f.aend(); I != E; ++I)
if (isPointerType(I->getType()))
getValueDest(*I);
- visit(G.getFunction()); // Single pass over the function
+ visit(f); // Single pass over the function
+ }
- // Not inlining, only eliminate trivially dead nodes.
- G.removeTriviallyDeadNodes();
+ // 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 visitMallocInst(MallocInst &MI) { handleAlloc(MI, DSNode::NewNode); }
- void visitAllocaInst(AllocaInst &AI) { handleAlloc(AI, DSNode::AllocaNode);}
- void handleAlloc(AllocationInst &AI, DSNode::NodeTy NT);
+ void visitMallocInst(MallocInst &MI) { handleAlloc(MI, true); }
+ void visitAllocaInst(AllocaInst &AI) { handleAlloc(AI, false); }
+ void handleAlloc(AllocationInst &AI, bool isHeap);
void visitPHINode(PHINode &PN);
- void visitGetElementPtrInst(GetElementPtrInst &GEP);
+ void visitGetElementPtrInst(User &GEP);
void visitReturnInst(ReturnInst &RI);
void visitLoadInst(LoadInst &LI);
void visitStoreInst(StoreInst &SI);
void visitCallInst(CallInst &CI);
+ void visitInvokeInst(InvokeInst &II);
void visitSetCondInst(SetCondInst &SCI) {} // SetEQ & friends are ignored
- void visitFreeInst(FreeInst &FI) {} // Ignore free instructions
+ void visitFreeInst(FreeInst &FI);
void visitCastInst(CastInst &CI);
- void visitInstruction(Instruction &I) {}
+ void visitInstruction(Instruction &I);
+
+ void visitCallSite(CallSite CS);
+ void MergeConstantInitIntoNode(DSNodeHandle &NH, Constant *C);
private:
// Helper functions used to implement the visitation functions...
/// createNode - Create a new DSNode, ensuring that it is properly added to
/// the graph.
///
- DSNode *createNode(DSNode::NodeTy NodeType, const Type *Ty);
-
- /// getValueNode - Return a DSNode that corresponds the the specified LLVM
- /// value. This either returns the already existing node, or creates a new
- /// one and adds it to the graph, if none exists.
- ///
- DSNodeHandle getValueNode(Value &V);
+ DSNode *createNode(const Type *Ty = 0) {
+ DSNode *N = new DSNode(Ty, &G); // Create the node
+ if (DisableFieldSensitivity) {
+ N->foldNodeCompletely();
+ if (DSNode *FN = N->getForwardNode())
+ N = FN;
+ }
+ return N;
+ }
- /// getValueDest - Return the DSNode that the actual value points to. This
- /// is basically the same thing as: getLink(getValueNode(V), 0)
+ /// setDestTo - Set the ScalarMap entry for the specified value to point to
+ /// the specified destination. If the Value already points to a node, make
+ /// sure to merge the two destinations together.
///
- DSNodeHandle &getValueDest(Value &V);
+ void setDestTo(Value &V, const DSNodeHandle &NH);
- /// getGlobalNode - Just like getValueNode, except the global node itself is
- /// returned, not a scalar node pointing to a global.
+ /// getValueDest - Return the DSNode that the actual value points to.
///
- DSNodeHandle &getGlobalNode(GlobalValue &V);
+ DSNodeHandle getValueDest(Value &V);
/// getLink - This method is used to return the specified link in the
/// specified node if one exists. If a link does not already exist (it's
- /// null), then we create a new node, link it, then return it. We must
- /// specify the type of the Node field we are accessing so that we know what
- /// type should be linked to if we need to create a new node.
+ /// null), then we create a new node, link it, then return it.
///
- DSNodeHandle &getLink(const DSNodeHandle &Node, unsigned Link,
- const Type *FieldTy);
+ DSNodeHandle &getLink(const DSNodeHandle &Node, unsigned Link = 0);
};
}
+using namespace DS;
+
//===----------------------------------------------------------------------===//
// DSGraph constructor - Simply use the GraphBuilder to construct the local
// graph.
-DSGraph::DSGraph(Function &F) : Func(&F) {
+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(*this, Nodes, RetNode, ValueMap, FunctionCalls);
- markIncompleteNodes();
+ 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
+ ++I;
+
+ markIncompleteNodes(DSGraph::MarkFormalArgs);
+
+ // Remove any nodes made dead due to merging...
+ removeDeadNodes(DSGraph::KeepUnreachableGlobals);
}
// Helper method implementations...
//
+/// getValueDest - Return the DSNode that the actual value points to.
+///
+DSNodeHandle GraphBuilder::getValueDest(Value &Val) {
+ Value *V = &Val;
+ if (V == Constant::getNullValue(V->getType()))
+ return 0; // Null doesn't point to anything, don't add to ScalarMap!
+
+ DSNodeHandle &NH = ScalarMap[V];
+ if (NH.getNode())
+ return NH; // Already have a node? Just return it...
+
+ // 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)) {
+ 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);
+ assert(I != ScalarMap.end() && "GEP didn't get processed right?");
+ NH = I->second;
+ } else {
+ // This returns a conservative unknown node for any unhandled ConstExpr
+ return NH = createNode()->setUnknownNodeMarker();
+ }
+ if (NH.getNode() == 0) { // (getelementptr null, X) returns null
+ ScalarMap.erase(V);
+ return 0;
+ }
+ return NH;
-// createNode - Create a new DSNode, ensuring that it is properly added to the
-// graph.
-//
-DSNode *GraphBuilder::createNode(DSNode::NodeTy NodeType, const Type *Ty) {
- DSNode *N = new DSNode(NodeType, Ty);
- Nodes.push_back(N);
- return N;
-}
-
-
-// getGlobalNode - Just like getValueNode, except the global node itself is
-// returned, not a scalar node pointing to a global.
-//
-DSNodeHandle &GraphBuilder::getGlobalNode(GlobalValue &V) {
- DSNodeHandle &NH = ValueMap[&V];
- if (NH.getNode()) return NH; // Already have a node? Just return it...
-
- // Create a new global node for this global variable...
- DSNode *G = createNode(DSNode::GlobalNode, V.getType()->getElementType());
- G->addGlobal(&V);
-
- // If this node has outgoing edges, make sure to recycle the same node for
- // each use. For functions and other global variables, this is unneccesary,
- // so avoid excessive merging by cloning these nodes on demand.
- //
- NH.setNode(G);
- return NH;
-}
-
+ } else if (ConstantIntegral *CI = dyn_cast<ConstantIntegral>(C)) {
+ // Random constants are unknown mem
+ return NH = createNode()->setUnknownNodeMarker();
+ } else {
+ assert(0 && "Unknown constant type!");
+ }
-// getValueNode - Return a DSNode that corresponds the the specified LLVM value.
-// This either returns the already existing node, or creates a new one and adds
-// it to the graph, if none exists.
-//
-DSNodeHandle GraphBuilder::getValueNode(Value &V) {
- assert(isPointerType(V.getType()) && "Should only use pointer scalars!");
-
- DSNodeHandle &NH = ValueMap[&V];
- if (NH.getNode()) return NH; // Already have a node? Just return it...
-
- // Otherwise we need to create a new scalar node...
- DSNode *N = createNode(DSNode::ScalarNode, V.getType());
-
- // If this is a global value, create the global pointed to.
- if (GlobalValue *GV = dyn_cast<GlobalValue>(&V)) {
- N->addEdgeTo(0, getGlobalNode(*GV));
- return DSNodeHandle(N, 0);
+ // 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);
} else {
- NH.setOffset(0);
- NH.setNode(N);
+ // Otherwise just create a shadow node
+ N = createNode();
}
+ NH.setNode(N); // Remember that we are pointing to it...
+ NH.setOffset(0);
return NH;
}
-/// getValueDest - Return the DSNode that the actual value points to. This
-/// is basically the same thing as: getLink(getValueNode(V), 0)
-///
-DSNodeHandle &GraphBuilder::getValueDest(Value &V) {
- return getLink(getValueNode(V), 0, V.getType());
-}
-
/// getLink - This method is used to return the specified link in the
/// specified node if one exists. If a link does not already exist (it's
/// specify the type of the Node field we are accessing so that we know what
/// type should be linked to if we need to create a new node.
///
-DSNodeHandle &GraphBuilder::getLink(const DSNodeHandle &node,
- unsigned LinkNo, const Type *FieldTy) {
+DSNodeHandle &GraphBuilder::getLink(const DSNodeHandle &node, unsigned LinkNo) {
DSNodeHandle &Node = const_cast<DSNodeHandle&>(node);
+ DSNodeHandle &Link = Node.getLink(LinkNo);
+ if (!Link.getNode()) {
+ // If the link hasn't been created yet, make and return a new shadow node
+ Link = createNode();
+ }
+ return Link;
+}
- DSNodeHandle *Link = Node.getLink(LinkNo);
- if (Link) return *Link;
-
- // If the link hasn't been created yet, make and return a new shadow node of
- // the appropriate type for FieldTy...
- //
- // If we are indexing with a typed pointer, then the thing we are pointing
- // to is of the pointed type. If we are pointing to it with an integer
- // (because of cast to an integer), we represent it with a void type.
- //
- const Type *ReqTy;
- if (const PointerType *Ptr = dyn_cast<PointerType>(FieldTy))
- ReqTy = Ptr->getElementType();
+/// setDestTo - Set the ScalarMap entry for the specified value to point to the
+/// specified destination. If the Value already points to a node, make sure to
+/// 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
- ReqTy = Type::VoidTy;
-
- DSNode *N = createNode(DSNode::ShadowNode, ReqTy);
- Node.setLink(LinkNo, N);
- return *Node.getLink(LinkNo);
+ AINH.mergeWith(NH);
}
/// Alloca & Malloc instruction implementation - Simply create a new memory
/// object, pointing the scalar to it.
///
-void GraphBuilder::handleAlloc(AllocationInst &AI, DSNode::NodeTy NodeType) {
- //DSNode *New = createNode(NodeType, Type::VoidTy);
- DSNode *New = createNode(NodeType, AI.getAllocatedType());
-
- // Make the scalar point to the new node...
- getValueNode(AI).addEdgeTo(New);
+void GraphBuilder::handleAlloc(AllocationInst &AI, bool isHeap) {
+ DSNode *N = createNode();
+ if (isHeap)
+ N->setHeapNodeMarker();
+ else
+ N->setAllocaNodeMarker();
+ setDestTo(AI, N);
}
// PHINode - Make the scalar for the PHI node point to all of the things the
void GraphBuilder::visitPHINode(PHINode &PN) {
if (!isPointerType(PN.getType())) return; // Only pointer PHIs
- DSNodeHandle &ScalarDest = getValueDest(PN);
+ DSNodeHandle &PNDest = ScalarMap[&PN];
for (unsigned i = 0, e = PN.getNumIncomingValues(); i != e; ++i)
- if (!isa<ConstantPointerNull>(PN.getIncomingValue(i)))
- ScalarDest.mergeWith(getValueDest(*PN.getIncomingValue(i)));
+ PNDest.mergeWith(getValueDest(*PN.getIncomingValue(i)));
}
-void GraphBuilder::visitGetElementPtrInst(GetElementPtrInst &GEP) {
+void GraphBuilder::visitGetElementPtrInst(User &GEP) {
DSNodeHandle Value = getValueDest(*GEP.getOperand(0));
+ if (Value.getNode() == 0) return;
+ // 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();
+
+ if (Value.getNode()->mergeTypeInfo(CurTy, Value.getOffset())) {
+ // If the node had to be folded... exit quickly
+ setDestTo(GEP, Value); // GEP result points to folded node
+ 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)) {
+
+ // If we already know this is an array being accessed, don't do anything...
+ if (!TopTypeRec.isArray) {
+ TopTypeRec.isArray = true;
+
+ // If we are treating some inner field pointer as an array, fold the node
+ // up because we cannot handle it right. This can come because of
+ // something like this: &((&Pt->X)[1]) == &Pt->Y
+ //
+ if (Value.getOffset()) {
+ // Value is now the pointer we want to GEP to be...
+ Value.getNode()->foldNodeCompletely();
+ setDestTo(GEP, Value); // GEP result points to folded node
+ return;
+ } else {
+ // This is a pointer to the first byte of the node. Make sure that we
+ // are pointing to the outter most type in the node.
+ // FIXME: We need to check one more case here...
+ }
+ }
+ }
+#endif
+
+ // All of these subscripts are indexing INTO the elements we have...
unsigned Offset = 0;
- const Type *CurTy = GEP.getOperand(0)->getType();
+ 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];
+ }
- for (unsigned i = 1, e = GEP.getNumOperands(); i != e; ++i)
- if (GEP.getOperand(i)->getType() == Type::LongTy) {
- // Get the type indexing into...
- const SequentialType *STy = cast<SequentialType>(CurTy);
+
+#if 0
+ if (const SequentialType *STy = cast<SequentialType>(*I)) {
CurTy = STy->getElementType();
if (ConstantSInt *CS = dyn_cast<ConstantSInt>(GEP.getOperand(i))) {
- if (isa<PointerType>(STy))
- std::cerr << "Pointer indexing not handled yet!\n";
- else
- Offset += CS->getValue()*TD.getTypeSize(CurTy);
+ Offset += CS->getValue()*TD.getTypeSize(CurTy);
} else {
// Variable index into a node. We must merge all of the elements of the
// sequential type here.
unsigned RawOffset = Offset+Value.getOffset();
// Loop over all of the elements of the array, merging them into the
- // zero'th element.
+ // zeroth element.
for (unsigned i = 1, e = ATy->getNumElements(); i != e; ++i)
// Merge all of the byte components of this array element
for (unsigned j = 0; j != ElSize; ++j)
N->mergeIndexes(RawOffset+j, RawOffset+i*ElSize+j);
}
}
- } 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);
// Value is now the pointer we want to GEP to be...
- getValueNode(GEP).addEdgeTo(Value);
+ setDestTo(GEP, Value);
}
void GraphBuilder::visitLoadInst(LoadInst &LI) {
- DSNodeHandle &Ptr = getValueDest(*LI.getOperand(0));
- Ptr.getNode()->NodeType |= DSNode::Read;
-
+ DSNodeHandle Ptr = getValueDest(*LI.getOperand(0));
+ if (Ptr.getNode() == 0) return;
+
+ // Make that the node is read from...
+ Ptr.getNode()->setReadMarker();
+
+ // Ensure a typerecord exists...
+ Ptr.getNode()->mergeTypeInfo(LI.getType(), Ptr.getOffset(), false);
+
if (isPointerType(LI.getType()))
- getValueNode(LI).addEdgeTo(getLink(Ptr, 0, LI.getType()));
+ setDestTo(LI, getLink(Ptr));
}
void GraphBuilder::visitStoreInst(StoreInst &SI) {
- DSNodeHandle &Dest = getValueDest(*SI.getOperand(1));
- Dest.getNode()->NodeType |= DSNode::Modified;
+ const Type *StoredTy = SI.getOperand(0)->getType();
+ DSNodeHandle Dest = getValueDest(*SI.getOperand(1));
+ if (Dest.getNode() == 0) return;
+
+ // Mark that the node is written to...
+ Dest.getNode()->setModifiedMarker();
+
+ // Ensure a type-record exists...
+ Dest.getNode()->mergeTypeInfo(StoredTy, Dest.getOffset());
// Avoid adding edges from null, or processing non-"pointer" stores
- if (isPointerType(SI.getOperand(0)->getType()) &&
- !isa<ConstantPointerNull>(SI.getOperand(0))) {
+ if (isPointerType(StoredTy))
Dest.addEdgeTo(getValueDest(*SI.getOperand(0)));
- }
}
void GraphBuilder::visitReturnInst(ReturnInst &RI) {
- if (RI.getNumOperands() && isPointerType(RI.getOperand(0)->getType()) &&
- !isa<ConstantPointerNull>(RI.getOperand(0))) {
- DSNodeHandle &Value = getValueDest(*RI.getOperand(0));
- Value.mergeWith(RetNode);
- RetNode = Value;
- }
+ if (RI.getNumOperands() && isPointerType(RI.getOperand(0)->getType()))
+ RetNode->mergeWith(getValueDest(*RI.getOperand(0)));
}
void GraphBuilder::visitCallInst(CallInst &CI) {
+ visitCallSite(&CI);
+}
+
+void GraphBuilder::visitInvokeInst(InvokeInst &II) {
+ visitCallSite(&II);
+}
+
+void GraphBuilder::visitCallSite(CallSite CS) {
+ // Special case handling of certain libc allocation functions here.
+ if (Function *F = CS.getCalledFunction())
+ if (F->isExternal())
+ if (F->getName() == "calloc") {
+ 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() == "memset") {
+ // Merge the first argument with the return value, and mark the memory
+ // modified.
+ DSNodeHandle RetNH = getValueDest(*CS.getInstruction());
+ RetNH.mergeWith(getValueDest(**CS.arg_begin()));
+ if (DSNode *N = RetNH.getNode())
+ N->setModifiedMarker();
+ return;
+ } else if (F->getName() == "memmove") {
+ // Merge the first & second arguments with the result, and mark the
+ // memory read and modified.
+ DSNodeHandle RetNH = getValueDest(*CS.getInstruction());
+ RetNH.mergeWith(getValueDest(**CS.arg_begin()));
+ RetNH.mergeWith(getValueDest(**(CS.arg_begin()+1)));
+ if (DSNode *N = RetNH.getNode())
+ N->setModifiedMarker()->setReadMarker();
+ return;
+ } else if (F->getName() == "bzero") {
+ // Mark the memory modified.
+ DSNodeHandle H = getValueDest(**CS.arg_begin());
+ if (DSNode *N = H.getNode())
+ N->setModifiedMarker();
+ return;
+ }
+
+
// Set up the return value...
DSNodeHandle RetVal;
- if (isPointerType(CI.getType()))
- RetVal = getLink(getValueNode(CI), 0, CI.getType());
-
- DSNodeHandle Callee;
- // Special case for a direct call, avoid creating spurious scalar node...
- if (GlobalValue *GV = dyn_cast<GlobalValue>(CI.getOperand(0)))
- Callee = getGlobalNode(*GV);
- else
- Callee = getLink(getValueNode(*CI.getOperand(0)), 0,
- CI.getOperand(0)->getType());
+ 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();
+ if (Callee == 0) {
+ std::cerr << "WARNING: Program is calling through a null pointer?\n"
+ << *I;
+ return; // Calling a null pointer?
+ }
+ }
std::vector<DSNodeHandle> Args;
- Args.reserve(CI.getNumOperands()-1);
+ Args.reserve(CS.arg_end()-CS.arg_begin());
// Calculate the arguments vector...
- for (unsigned i = 1, e = CI.getNumOperands(); i != e; ++i)
- if (isPointerType(CI.getOperand(i)->getType()))
- Args.push_back(getLink(getValueNode(*CI.getOperand(i)), 0,
- CI.getOperand(i)->getType()));
+ for (CallSite::arg_iterator I = CS.arg_begin(), E = CS.arg_end(); I != E; ++I)
+ if (isPointerType((*I)->getType()))
+ Args.push_back(getValueDest(**I));
// Add a new function call entry...
- FunctionCalls.push_back(DSCallSite(CI, RetVal, Callee, Args));
+ if (Callee)
+ FunctionCalls->push_back(DSCallSite(CS, RetVal, Callee, Args));
+ else
+ FunctionCalls->push_back(DSCallSite(CS, RetVal, CS.getCalledFunction(),
+ Args));
+}
+
+void GraphBuilder::visitFreeInst(FreeInst &FI) {
+ // Mark that the node is written to...
+ DSNode *N = getValueDest(*FI.getOperand(0)).getNode();
+ N->setModifiedMarker();
+ N->setHeapNodeMarker();
}
/// Handle casts...
void GraphBuilder::visitCastInst(CastInst &CI) {
- if (isPointerType(CI.getType()) && isPointerType(CI.getOperand(0)->getType()))
- getValueNode(CI).addEdgeTo(getLink(getValueNode(*CI.getOperand(0)), 0,
- CI.getOperand(0)->getType()));
+ if (isPointerType(CI.getType()))
+ if (isPointerType(CI.getOperand(0)->getType())) {
+ // Cast one pointer to the other, just act like a copy instruction
+ setDestTo(CI, getValueDest(*CI.getOperand(0)));
+ } else {
+ // Cast something (floating point, small integer) to a pointer. We need
+ // to track the fact that the node points to SOMETHING, just something we
+ // don't know about. Make an "Unknown" node.
+ //
+ setDestTo(CI, createNode()->setUnknownNodeMarker());
+ }
}
+// visitInstruction - For all other instruction types, if we have any arguments
+// that are of pointer type, make them have unknown composition bits, and merge
+// the nodes together.
+void GraphBuilder::visitInstruction(Instruction &Inst) {
+ DSNodeHandle CurNode;
+ if (isPointerType(Inst.getType()))
+ CurNode = getValueDest(Inst);
+ for (User::op_iterator I = Inst.op_begin(), E = Inst.op_end(); I != E; ++I)
+ if (isPointerType((*I)->getType()))
+ CurNode.mergeWith(getValueDest(**I));
+
+ if (CurNode.getNode())
+ CurNode.getNode()->setUnknownNodeMarker();
+}
+
//===----------------------------------------------------------------------===//
// 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 {
+ 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(getAnalysis<TargetData>());
+
+ const TargetData &TD = getAnalysis<TargetData>();
+
+ // 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(TD, *I, GlobalsGraph)));
+
+ 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);
+
+ GlobalsGraph->markIncompleteNodes(DSGraph::MarkFormalArgs);
+ GlobalsGraph->removeTriviallyDeadNodes();
+ return false;
+}
+
// releaseMemory - If the pass pipeline is done with this pass, we can release
// our memory... here...
//
void LocalDataStructures::releaseMemory() {
- for (std::map<const Function*, DSGraph*>::iterator I = DSInfo.begin(),
- E = DSInfo.end(); I != E; ++I)
- delete I->second;
+ for (hash_map<Function*, DSGraph*>::iterator I = DSInfo.begin(),
+ E = DSInfo.end(); I != E; ++I) {
+ I->second->getReturnNodes().erase(I->first);
+ if (I->second->getReturnNodes().empty())
+ delete I->second;
+ }
// Empty map so next time memory is released, data structures are not
// re-deleted.
DSInfo.clear();
+ delete GlobalsGraph;
+ GlobalsGraph = 0;
}
-bool LocalDataStructures::run(Module &M) {
- // 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)));
- return false;
-}