-//===- ComputeLocal.cpp - Compute a local data structure graph for a fn ---===//
+//===- 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/Function.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/GlobalVariable.h"
#include "llvm/DerivedTypes.h"
+#include "llvm/Instructions.h"
+#include "llvm/Support/GetElementPtrTypeIterator.h"
#include "llvm/Support/InstVisitor.h"
-using std::map;
-using std::vector;
+#include "llvm/Target/TargetData.h"
+#include "Support/CommandLine.h"
+#include "Support/Debug.h"
+#include "Support/Timer.h"
-//===----------------------------------------------------------------------===//
-// GraphBuilder Class
-//===----------------------------------------------------------------------===//
-//
-// This class is the builder class that constructs the local data structure
-// graph by performing a single pass over the function in question.
+// FIXME: This should eventually be a FunctionPass that is automatically
+// aggregated into a Pass.
//
+#include "llvm/Module.h"
+
+using namespace llvm;
+
+static RegisterAnalysis<LocalDataStructures>
+X("datastructure", "Local Data Structure Analysis");
+
+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 (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
+ //===--------------------------------------------------------------------===//
+ //
+ /// This class is the builder class that constructs the local data structure
+ /// graph by performing a single pass over the function in question.
+ ///
class GraphBuilder : InstVisitor<GraphBuilder> {
DSGraph &G;
- vector<DSNode*> &Nodes;
- DSNodeHandle &RetNode; // Node that gets returned...
- map<Value*, DSNodeHandle> &ValueMap;
- vector<vector<DSNodeHandle> > &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<vector<DSNodeHandle> > &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)
- if (isa<PointerType>(I->getType()))
- getValueNode(*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 visitInstruction(Instruction &I); // Visit unsafe ptr instruction
+ void visitFreeInst(FreeInst &FI);
+ void visitCastInst(CastInst &CI);
+ 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.
- //
- DSNode *getValueNode(Value &V);
-
- // getGlobalNode - Just like getValueNode, except the global node itself is
- // returned, not a scalar node pointing to a global.
- //
- DSNode *getGlobalNode(GlobalValue &V);
-
- // getLink - This method is used to either 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.
- //
- DSNode *getLink(DSNode *Node, unsigned Link);
-
- // getSubscriptedNode - Perform the basic getelementptr functionality that
- // must be factored out of gep, load and store while they are all MAI's.
- //
- DSNode *getSubscriptedNode(MemAccessInst &MAI, DSNode *Ptr);
+ /// createNode - Create a new DSNode, ensuring that it is properly added to
+ /// the graph.
+ ///
+ 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;
+ }
+
+ /// 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 setDestTo(Value &V, const DSNodeHandle &NH);
+
+ /// getValueDest - Return the DSNode that the actual value points to.
+ ///
+ 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.
+ ///
+ 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), RetNode(0) {
+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))
+ ScalarMap.erase(I++);
+ 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;
+
+ } else if (ConstantIntegral *CI = dyn_cast<ConstantIntegral>(C)) {
+ // Random constants are unknown mem
+ return NH = createNode()->setUnknownNodeMarker();
+ } else {
+ assert(0 && "Unknown constant type!");
+ }
-// 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.
-//
-DSNode *GraphBuilder::getGlobalNode(GlobalValue &V) {
- DSNodeHandle &NH = ValueMap[&V];
- if (NH) 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 = G;
- return G;
-}
-
-
-// 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.
-//
-DSNode *GraphBuilder::getValueNode(Value &V) {
- assert(isa<PointerType>(V.getType()) && "Should only use pointer scalars!");
- if (!isa<GlobalValue>(V)) {
- DSNodeHandle &NH = ValueMap[&V];
- if (NH) 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)) {
- DSNode *G = getGlobalNode(*GV);
- N->addEdgeTo(G);
+ // 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 {
- ValueMap[&V] = N;
+ // Otherwise just create a shadow node
+ N = createNode();
}
- return N;
+ NH.setNode(N); // Remember that we are pointing to it...
+ NH.setOffset(0);
+ return NH;
}
-// getLink - This method is used to either 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.
-//
-DSNode *GraphBuilder::getLink(DSNode *Node, unsigned Link) {
- assert(Link < Node->getNumLinks() && "Link accessed out of range!");
- if (Node->getLink(Link) == 0) {
- DSNode::NodeTy NT;
- const Type *Ty;
-
- switch (Node->getType()->getPrimitiveID()) {
- case Type::PointerTyID:
- Ty = cast<PointerType>(Node->getType())->getElementType();
- NT = DSNode::ShadowNode;
- break;
- case Type::ArrayTyID:
- Ty = cast<ArrayType>(Node->getType())->getElementType();
- NT = DSNode::SubElement;
- break;
- case Type::StructTyID:
- Ty = cast<StructType>(Node->getType())->getContainedType(Link);
- NT = DSNode::SubElement;
- break;
- default:
- assert(0 && "Unexpected type to dereference!");
- abort();
- }
-
- DSNode *New = createNode(NT, Ty);
- Node->addEdgeTo(Link, New);
+/// 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.
+///
+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 Node->getLink(Link);
+ return Link;
}
-// getSubscriptedNode - Perform the basic getelementptr functionality that must
-// be factored out of gep, load and store while they are all MAI's.
-//
-DSNode *GraphBuilder::getSubscriptedNode(MemAccessInst &MAI, DSNode *Ptr) {
- for (unsigned i = MAI.getFirstIndexOperandNumber(), e = MAI.getNumOperands();
- i != e; ++i)
- if (MAI.getOperand(i)->getType() == Type::UIntTy)
- Ptr = getLink(Ptr, 0);
- else if (MAI.getOperand(i)->getType() == Type::UByteTy)
- Ptr = getLink(Ptr, cast<ConstantUInt>(MAI.getOperand(i))->getValue());
-
- if (MAI.getFirstIndexOperandNumber() == MAI.getNumOperands())
- Ptr = getLink(Ptr, 0); // All MAI's have an implicit 0 if nothing else.
-
- return Ptr;
+
+/// 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
+ AINH.mergeWith(NH);
}
+
//===----------------------------------------------------------------------===//
// Specific instruction type handler implementations...
//
-// Alloca & Malloc instruction implementation - Simply create a new memory
-// object, pointing the scalar to it.
-//
-void GraphBuilder::handleAlloc(AllocationInst &AI, DSNode::NodeTy NodeType) {
- DSNode *Scalar = getValueNode(AI);
- DSNode *New = createNode(NodeType, AI.getAllocatedType());
- Scalar->addEdgeTo(New); // Make the scalar point to the new node...
+/// Alloca & Malloc instruction implementation - Simply create a new memory
+/// object, pointing the scalar to it.
+///
+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
// incoming values point to... which effectively causes them to be merged.
//
void GraphBuilder::visitPHINode(PHINode &PN) {
- if (!isa<PointerType>(PN.getType())) return; // Only pointer PHIs
+ if (!isPointerType(PN.getType())) return; // Only pointer PHIs
- DSNode *Scalar = getValueNode(PN);
- DSNode *ScalarDest = getLink(Scalar, 0);
+ DSNodeHandle &PNDest = ScalarMap[&PN];
for (unsigned i = 0, e = PN.getNumIncomingValues(); i != e; ++i)
- ScalarDest->mergeWith(getLink(getValueNode(*PN.getIncomingValue(i)), 0));
+ PNDest.mergeWith(getValueDest(*PN.getIncomingValue(i)));
}
-void GraphBuilder::visitGetElementPtrInst(GetElementPtrInst &GEP) {
- DSNode *Ptr = getSubscriptedNode(GEP, getValueNode(*GEP.getOperand(0)));
- getValueNode(GEP)->addEdgeTo(Ptr);
+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;
+ 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];
+ }
+
+
+#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 {
+ // Variable index into a node. We must merge all of the elements of the
+ // sequential type here.
+ if (isa<PointerType>(STy))
+ std::cerr << "Pointer indexing not handled yet!\n";
+ else {
+ const ArrayType *ATy = cast<ArrayType>(STy);
+ unsigned ElSize = TD.getTypeSize(CurTy);
+ DSNode *N = Value.getNode();
+ assert(N && "Value must have a node!");
+ unsigned RawOffset = Offset+Value.getOffset();
+
+ // Loop over all of the elements of the array, merging them into the
+ // 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);
+ }
+ }
+ }
+#endif
+
+ // Add in the offset calculated...
+ Value.setOffset(Value.getOffset()+Offset);
+
+ // Value is now the pointer we want to GEP to be...
+ setDestTo(GEP, Value);
}
void GraphBuilder::visitLoadInst(LoadInst &LI) {
- DSNode *Ptr = getSubscriptedNode(LI, getValueNode(*LI.getOperand(0)));
- if (!isa<PointerType>(LI.getType())) return; // Only pointer PHIs
- getValueNode(LI)->addEdgeTo(getLink(Ptr, 0));
+ 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()))
+ setDestTo(LI, getLink(Ptr));
}
void GraphBuilder::visitStoreInst(StoreInst &SI) {
- DSNode *DestPtr = getSubscriptedNode(SI, getValueNode(*SI.getOperand(1)));
- if (!isa<PointerType>(SI.getOperand(0)->getType())) return;
- DSNode *Value = getValueNode(*SI.getOperand(0));
- DestPtr->addEdgeTo(getLink(Value, 0));
+ 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(StoredTy))
+ Dest.addEdgeTo(getValueDest(*SI.getOperand(0)));
}
void GraphBuilder::visitReturnInst(ReturnInst &RI) {
- if (RI.getNumOperands() && isa<PointerType>(RI.getOperand(0)->getType())) {
- DSNode *Value = getLink(getValueNode(*RI.getOperand(0)), 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) {
- // Add a new function call entry...
- FunctionCalls.push_back(vector<DSNodeHandle>());
- vector<DSNodeHandle> &Args = FunctionCalls.back();
+ 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...
- if (isa<PointerType>(CI.getType()))
- Args.push_back(getLink(getValueNode(CI), 0));
+ 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();
+ 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(CS.arg_end()-CS.arg_begin());
+
+ // Calculate the arguments vector...
+ 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...
+ if (Callee)
+ FunctionCalls->push_back(DSCallSite(CS, RetVal, Callee, Args));
else
- Args.push_back(0);
+ 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();
+}
- unsigned Start = 0;
- // Special case for direct call, avoid creating spurious scalar node...
- if (GlobalValue *GV = dyn_cast<GlobalValue>(CI.getOperand(0))) {
- Args.push_back(getGlobalNode(*GV));
- Start = 1;
+/// Handle casts...
+void GraphBuilder::visitCastInst(CastInst &CI) {
+ 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;
}
- // Pass the arguments in...
- for (unsigned i = Start, e = CI.getNumOperands(); i != e; ++i)
- if (isa<PointerType>(CI.getOperand(i)->getType()))
- Args.push_back(getLink(getValueNode(*CI.getOperand(i)), 0));
+ 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());
}
-// visitInstruction - All safe instructions have been processed above, this case
-// is where unsafe ptr instructions land.
+
+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 GraphBuilder::visitInstruction(Instruction &I) {
- // If the return type is a pointer, mark the pointed node as being a cast node
- if (isa<PointerType>(I.getType()))
- getLink(getValueNode(I), 0)->NodeType |= DSNode::CastNode;
-
- // If any operands are pointers, mark the pointed nodes as being a cast node
- for (Instruction::op_iterator i = I.op_begin(), E = I.op_end(); i!=E; ++i)
- if (isa<PointerType>(i->get()->getType()))
- getLink(getValueNode(*i->get()), 0)->NodeType |= DSNode::CastNode;
+void LocalDataStructures::releaseMemory() {
+ 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;
}
projects / oota-llvm.git / blobdiff