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llvm / llvm-archive / refs/heads/SVA / . / poolalloc / lib / DSA / Local.cpp
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//===- 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/ADT/Statistic.h"
#include "dsa/DataStructure.h"
#include "dsa/DSGraph.h"
#include "llvm/Constants.h"
#include "llvm/DerivedTypes.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 "llvm/Support/CommandLine.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/Timer.h"
#include "poolalloc/Config/config.h"
#include <iostream>
#include <queue>
// FIXME: This should eventually be a FunctionPass that is automatically
// aggregated into a Pass.
//
#include "llvm/Module.h"
using namespace llvm;
#ifdef LLVA_KERNEL
static Statistic<> CacheAllocs ("dsa", "Number of kmem_cache_alloc calls");
static Statistic<> KMallocs ("dsa", "Number of kmalloc calls");
static Statistic<> GlobalPools ("dsa", "Number of global pools");
std::map<unsigned int, Function*> syscalls;
#endif
static Statistic<> CastTraceT ("dsa", "Number of int casts traced successfully");
static Statistic<> CastTraceF ("dsa", "Number of int casts not traced");
Statistic<> stat_unknown ("dsa", "Number of markunknowns");
static cl::opt<bool>
Crash("dsa-crash", cl::Hidden,
cl::desc("Crash on unknowns"));
static cl::opt<int>
CrashAt("dsa-crashat", cl::Hidden,
cl::desc("Crash on unknowns"));
static bool DebugUnknown = true;
static int CrashCur = 0;
DSNode *DSNode::setUnknownNodeMarker() {
if (Crash && CrashCur == CrashAt) assert(0);
++CrashCur;
++stat_unknown;
NodeType |= UnknownNode;
return this;
}
static RegisterPass<LocalDataStructures>
X("datastructure", "Local Data Structure Analysis");
static cl::opt<bool>
TrackIntegersAsPointers("dsa-track-integers", cl::Hidden,
cl::desc("If this is set, track integers as potential pointers"));
static cl::list<std::string>
AllocList("dsa-alloc-list",
cl::value_desc("list"),
cl::desc("List of functions that allocate memory from the heap"),
cl::CommaSeparated, cl::Hidden);
static cl::list<std::string>
IOAllocList("dsa-ioalloc-list",
cl::value_desc("list"),
cl::desc("List of functions that allocate memory for I/O"),
cl::CommaSeparated, cl::Hidden);
static cl::list<std::string>
FreeList("dsa-free-list",
cl::value_desc("list"),
cl::desc("List of functions that free memory from the heap"),
cl::CommaSeparated, cl::Hidden);
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;
DSNodeHandle *RetNode; // Node that gets returned...
DSScalarMap &ScalarMap;
std::list<DSCallSite> *FunctionCalls;
Value * KMallocPool;
public:
GraphBuilder(Function &f, DSGraph &g, DSNodeHandle &retNode,
std::list<DSCallSite> &fc)
: G(g), RetNode(&retNode), ScalarMap(G.getScalarMap()),
FunctionCalls(&fc) {
// Find the type unsafe pool in the program
KMallocPool = f.getParent()->getNamedGlobal ("KmallocPool");
#if 1
//
// Determine if the function somehow escapes
//
bool escapes = false;
if (!(f.hasInternalLinkage())) {
escapes = true;
}
Value::use_iterator U;
for (U=f.use_begin(); U != f.use_end(); ++U) {
if (isa<GlobalValue>(U)) {
// std::cerr << "LLVA: isa: " << f.getName() << " " << *U << std::endl;
escapes = true;
break;
}
}
#endif
// Create scalar nodes for all pointer arguments...
for (Function::arg_iterator I = f.arg_begin(), E = f.arg_end();
I != E; ++I) {
if (isPointerType(I->getType())) {
DSNode * Node = getValueDest(*I).getNode();
if (!(f.hasInternalLinkage())) {
Node->setExternalMarker();
}
}
}
visit(f); // Single pass over the function
#if 0
std::cerr << "LLVA: Function " << f.getName() << "\n";
for (DSScalarMap::iterator I = ScalarMap.begin(), E=ScalarMap.end();
I != E;
++I)
{
std::cerr << "LLVA:\t" << I->first->getName() << ": " << (void *)(I->second.getNode()) << "\n";
}
#endif
}
// 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, true); }
void visitAllocaInst(AllocaInst &AI) { handleAlloc(AI, false); }
void handleAlloc(AllocationInst &AI, bool isHeap);
void visitPHINode(PHINode &PN);
void visitSelectInst(SelectInst &SI);
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);
void visitFreeInst(FreeInst &FI);
void visitCastInst(CastInst &CI);
void visitInstruction(Instruction &I);
bool visitIntrinsic(CallSite CS, Function* F);
bool visitExternal(CallSite CS, Function* F);
void visitCallSite(CallSite CS);
void visitVAArgInst(VAArgInst &I);
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(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;
}
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(EquivalenceClasses<GlobalValue*> &ECs, const TargetData &td,
Function &F, DSGraph *GG)
: GlobalsGraph(GG), ScalarMap(ECs), 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], FunctionCalls);
#ifndef NDEBUG
Timer::addPeakMemoryMeasurement();
#endif
// 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);
markUnknownNodes();
// Remove any nodes made dead due to merging...
removeDeadNodes(DSGraph::KeepUnreachableGlobals);
}
//===----------------------------------------------------------------------===//
// Helper method implementations...
//
static bool getSourcePointerValues(Value* V, std::set<Value*>& sources) {
std::queue<Value*> tocheck;
std::set<Value*> visited;
tocheck.push(V);
while (!tocheck.empty()) {
V = tocheck.front();
tocheck.pop();
if (visited.find(V) == visited.end()) {
visited.insert(V);
if (isa<PointerType>(V->getType())) {
sources.insert(V);
} else if (ConstantInt* N = dyn_cast<ConstantInt>(V)) {
if (!(-N->getSExtValue() <= 124 && -N->getSExtValue() >= 0)) {
goto fail;
}
} else if (PHINode* N = dyn_cast<PHINode>(V)) {
for (unsigned x = 0; x < N->getNumIncomingValues(); ++x)
tocheck.push(N->getIncomingValue(x));
} else if (CastInst* N = dyn_cast<CastInst>(V)) {
tocheck.push(N->getOperand(0));
} else if (ConstantExpr* N = dyn_cast<ConstantExpr>(V)) {
if (N->getOpcode() == Instruction::Cast) {
tocheck.push(N->getOperand(0));
} else {
goto fail;
}
#ifdef LLVA_KERNEL
} else if (CallInst * CI = dyn_cast<CallInst>(V)) {
Function * F = CI->getCalledFunction();
if (!F) goto fail;
if ((F->hasName()) && (F->getName() == "llva_do_index")) {
tocheck.push(CI->getOperand(1));
} else {
goto fail;
}
#endif
} else {
goto fail;
}
}
}
++CastTraceT;
return true;
fail:
++CastTraceF;
std::cerr << "Int2Ptr: fail ";
V->dump();
return false;
}
/// getValueDest - Return the DSNode that the actual value points to.
///
DSNodeHandle GraphBuilder::getValueDest(Value &Val) {
Value *V = &Val;
if (isa<Constant>(V) && cast<Constant>(V)->isNullValue())
return 0; // Null doesn't point to anything, don't add to ScalarMap!
DSNodeHandle &NH = ScalarMap[V];
if (!NH.isNull())
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.
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)) {
std::set<Value*> sources;
if (getSourcePointerValues(CE, sources)) {
NH = createNode();
for (std::set<Value*>::iterator ii = sources.begin(), ee = sources.end();
ii != ee; ++ii)
NH.mergeWith(getValueDest(**ii));
} else if (CE->getOpcode() == Instruction::GetElementPtr) {
visitGetElementPtrInst(*CE);
DSScalarMap::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.isNull()) { // (getelementptr null, X) returns null
ScalarMap.erase(V);
return 0;
}
return NH;
} else if (isa<UndefValue>(C)) {
ScalarMap.erase(V);
return 0;
} else {
assert(0 && "Unknown constant type!");
}
N = createNode(); // just create a shadow node
} else {
// Otherwise just create a shadow node
N = createNode();
}
NH.setTo(N, 0); // Remember that we are pointing to it...
return NH;
}
/// 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.isNull()) {
// If the link hasn't been created yet, make and return a new shadow node
Link = createNode();
}
return Link;
}
/// 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) {
ScalarMap[&V].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, 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 (!isPointerType(PN.getType())) return; // Only pointer PHIs
DSNodeHandle PNDest = getValueDest(PN);
for (unsigned i = 0, e = PN.getNumIncomingValues(); i != e; ++i)
PNDest.mergeWith(getValueDest(*PN.getIncomingValue(i)));
}
void GraphBuilder::visitSelectInst(SelectInst &SI) {
if (!isPointerType(SI.getType())) return; // Only pointer Selects
DSNodeHandle Dest = getValueDest(SI);
Dest.mergeWith(getValueDest(*SI.getOperand(1)));
Dest.mergeWith(getValueDest(*SI.getOperand(2)));
}
void GraphBuilder::visitSetCondInst(SetCondInst &SCI) {
if (!isPointerType(SCI.getOperand(0)->getType()) ||
isa<ConstantPointerNull>(SCI.getOperand(1))) return; // Only pointers
getValueDest(*SCI.getOperand(0)).mergeWith(getValueDest(*SCI.getOperand(1)));
}
void GraphBuilder::visitGetElementPtrInst(User &GEP) {
#ifdef LLVA_KERNEL
#if 0
int debug = 0;
if (isa<Instruction>(GEP)) {
Instruction * IGEP = (Instruction *)(&GEP);
if (IGEP->getParent()->getParent()->getName() == "alloc_vfsmnt")
{
#if 0
if (G.getPoolDescriptorsMap().count(N) != 0)
if (G.getPoolDescriptorsMap()[N])
std::cerr << "LLVA: GEP[" << count << "]: Pool for " << GEP.getName() << " is " << G.getPoolDescriptorsMap()[N]->getMetaPoolValue()->getName() << "\n";
#else
debug = 1;
#endif
}
}
#endif
#endif
DSNodeHandle Value = getValueDest(*GEP.getOperand(0));
if (Value.isNull())
Value = createNode();
// 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 || (!Value.isNull() &&
Value.getNode()->isNodeCompletelyFolded())) {
setDestTo(GEP, Value);
#if 0
if (debug) std::cerr << "LLVA: GEP: All Zeros\n";
if (G.getPoolDescriptorsMap()[Value.getNode()])
std::cerr << "LLVA: GEP: Pool for " << GEP.getName() << " is " << G.getPoolDescriptorsMap()[Value.getNode()]->getName() << "\n";
#endif
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 &&
(!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) {
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)) {
const ConstantInt* CUI = cast<ConstantInt>(I.getOperand());
unsigned FieldNo =
CUI->getType()->isSigned() ? CUI->getSExtValue() : CUI->getZExtValue();
Offset += (unsigned)TD.getStructLayout(STy)->MemberOffsets[FieldNo];
} else if (isa<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 (ConstantInt *CS = dyn_cast<ConstantInt>(GEP.getOperand(i))) {
Offset +=
(CS->getType()->isSigned() ? CS->getSExtValue() : CS->getZExtValue())
* 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);
// Check the offset
DSNode *N = Value.getNode();
if (N &&
!N->isNodeCompletelyFolded() &&
(N->getSize() != 0 || Offset != 0) &&
!N->isForwarding()) {
if ((Offset >= N->getSize()) || int(Offset) < 0) {
// Accessing offsets out of node size range
// This is seen in the "magic" struct in named (from bind), where the
// fourth field is an array of length 0, presumably used to create struct
// instances of different sizes
// Collapse the node since its size is now variable
N->foldNodeCompletely();
}
}
// Value is now the pointer we want to GEP to be...
setDestTo(GEP, Value);
#if 0
if (debug && (isa<Instruction>(GEP))) {
Instruction * IGEP = (Instruction *)(&GEP);
DSNode * N = Value.getNode();
if (IGEP->getParent()->getParent()->getName() == "alloc_vfsmnt")
{
if (G.getPoolDescriptorsMap().count(N) != 0)
if (G.getPoolDescriptorsMap()[N])
std::cerr << "LLVA: GEP[" << 0 << "]: Pool for " << GEP.getName() << " is " << G.getPoolDescriptorsMap()[N]->getName() << "\n";
}
}
#endif
}
void GraphBuilder::visitLoadInst(LoadInst &LI) {
DSNodeHandle Ptr = getValueDest(*LI.getOperand(0));
if (Ptr.isNull())
Ptr = createNode();
// 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));
#if 0
if (G.getPoolDescriptorsMap()[getLink(Ptr).getNode()])
std::cerr << "LLVA: Load: Pool for " << LI.getName() << " is " << G.getPoolDescriptorsMap()[getLink(Ptr).getNode()]->getName() << "\n";
#endif
}
void GraphBuilder::visitStoreInst(StoreInst &SI) {
const Type *StoredTy = SI.getOperand(0)->getType();
DSNodeHandle Dest = getValueDest(*SI.getOperand(1));
if (Dest.isNull()) 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)));
#ifdef LLVA_KERNEL
#if 0
{
if (SI.getParent()->getParent()->getName() == "alloc_vfsmnt") {
DSNode * N = getValueDest(*SI.getOperand(1)).getNode();
if (N->getMP())
std::cerr << "LLVA: Store: Pool for " << SI.getName() << " is " << N->getMP() << "\n";
}
}
#endif
#endif
}
void GraphBuilder::visitReturnInst(ReturnInst &RI) {
if (RI.getNumOperands() && isPointerType(RI.getOperand(0)->getType()))
RetNode->mergeWith(getValueDest(*RI.getOperand(0)));
}
void GraphBuilder::visitVAArgInst(VAArgInst &I) {
//FIXME: also updates the argument
DSNodeHandle Ptr = getValueDest(*I.getOperand(0));
if (Ptr.isNull()) return;
// Make that the node is read from.
Ptr.getNode()->setReadMarker();
// Ensure a type record exists.
DSNode *PtrN = Ptr.getNode();
PtrN->mergeTypeInfo(I.getType(), Ptr.getOffset(), false);
if (isPointerType(I.getType()))
setDestTo(I, getLink(Ptr));
}
void GraphBuilder::visitCallInst(CallInst &CI) {
visitCallSite(&CI);
}
void GraphBuilder::visitInvokeInst(InvokeInst &II) {
visitCallSite(&II);
}
/// returns true if the intrinsic is handled
bool GraphBuilder::visitIntrinsic(CallSite CS, Function *F) {
switch (F->getIntrinsicID()) {
case Intrinsic::vastart:
getValueDest(*CS.getInstruction()).getNode()->setAllocaNodeMarker();
return true;
case Intrinsic::vacopy:
getValueDest(*CS.getInstruction()).
mergeWith(getValueDest(**(CS.arg_begin())));
return true;
case Intrinsic::vaend:
case Intrinsic::dbg_func_start:
case Intrinsic::dbg_region_end:
case Intrinsic::dbg_stoppoint:
return true; // noop
case Intrinsic::memcpy_i32:
case Intrinsic::memcpy_i64:
case Intrinsic::memmove_i32:
case Intrinsic::memmove_i64: {
// 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 true;
}
case Intrinsic::memset_i32:
case Intrinsic::memset_i64:
// Mark the memory modified.
if (DSNode *N = getValueDest(**CS.arg_begin()).getNode())
N->setModifiedMarker();
return true;
default:
DEBUG(std::cerr << "[dsa:local] Unhandled intrinsic: " << F->getName() << "\n");
return false;
}
}
/// returns true if the external is a recognized libc function with a
/// known (and generated) graph
bool GraphBuilder::visitExternal(CallSite CS, Function *F) {
if (F->getName() == "calloc"
|| F->getName() == "posix_memalign"
|| F->getName() == "memalign" || F->getName() == "valloc") {
setDestTo(*CS.getInstruction(),
createNode()->setHeapNodeMarker()->setModifiedMarker());
return true;
} else if (F->getName() == "realloc") {
DSNodeHandle RetNH = getValueDest(*CS.getInstruction());
if (CS.arg_begin() != CS.arg_end())
RetNH.mergeWith(getValueDest(**CS.arg_begin()));
if (DSNode *N = RetNH.getNode())
N->setHeapNodeMarker()->setModifiedMarker()->setReadMarker();
return true;
} 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 true;
} else if (F->getName() == "free") {
// Mark that the node is written to...
if (DSNode *N = getValueDest(**CS.arg_begin()).getNode())
N->setModifiedMarker()->setHeapNodeMarker();
} 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" ||
F->getName() == "strlen") {
// 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 true;
} else if (F->getName() == "memchr") {
DSNodeHandle RetNH = getValueDest(**CS.arg_begin());
DSNodeHandle Result = getValueDest(*CS.getInstruction());
RetNH.mergeWith(Result);
if (DSNode *N = RetNH.getNode())
N->setReadMarker();
return true;
} else if (F->getName() == "read" || F->getName() == "pipe" ||
F->getName() == "wait" || F->getName() == "time" ||
F->getName() == "getrusage") {
// 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 true;
} 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 true;
} 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 true;
} 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") {
// ICC doesn't handle getting the iterator, decrementing and
// dereferencing it in one operation without error. Do it in 2 steps
CallSite::arg_iterator compit = CS.arg_end();
Result.mergeWith(getValueDest(**--compit));
}
return true;
} 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 true;
} 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 true;
} 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.
CallSite::arg_iterator compit = CS.arg_end();
DSNodeHandle H = getValueDest(**--compit);
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 true;
} 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 true;
} 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.
CallSite::arg_iterator compit = CS.arg_end();
DSNodeHandle H = getValueDest(**--compit);
if (DSNode *N = H.getNode()) {
N->setReadMarker()->setModifiedMarker();
FunctionType::param_iterator compit2 = F->getFunctionType()->param_end();
const Type *ArgTy = *--compit2;
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 true;
} 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()) {
FunctionType::param_iterator compit2 = F->getFunctionType()->param_end();
const Type *ArgTy = *--compit2;
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 true;
} 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 true;
} 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 true;
} 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 true;
} 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 true;
} 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 true;
} else if (F->getName() == "__assert_fail") {
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 true;
} else if (F->getName() == "modf" && CS.arg_end()-CS.arg_begin() == 2) {
// This writes its second argument, and forces it to double.
CallSite::arg_iterator compit = CS.arg_end();
DSNodeHandle H = getValueDest(**--compit);
if (DSNode *N = H.getNode()) {
N->setModifiedMarker();
N->mergeTypeInfo(Type::DoubleTy, H.getOffset());
}
return true;
} else if (F->getName() == "strcat" || F->getName() == "strncat") {
//This might be making unsafe assumptions about usage
//Merge return and first arg
DSNodeHandle RetNH = getValueDest(*CS.getInstruction());
RetNH.mergeWith(getValueDest(**CS.arg_begin()));
if (DSNode *N = RetNH.getNode())
N->setHeapNodeMarker()->setModifiedMarker()->setReadMarker();
//and read second pointer
if (DSNode *N = getValueDest(**(CS.arg_begin() + 1)).getNode())
N->setReadMarker();
return true;
} else if (F->getName() == "strcpy" || F->getName() == "strncpy") {
//This might be making unsafe assumptions about usage
//Merge return and first arg
DSNodeHandle RetNH = getValueDest(*CS.getInstruction());
RetNH.mergeWith(getValueDest(**CS.arg_begin()));
if (DSNode *N = RetNH.getNode())
N->setHeapNodeMarker()->setModifiedMarker();
//and read second pointer
if (DSNode *N = getValueDest(**(CS.arg_begin() + 1)).getNode())
N->setReadMarker();
return true;
#ifdef LLVA_KERNEL
} else if (F->getName() == "llva_print_icontext") {
DSNodeHandle RetNH = getValueDest(**(CS.arg_begin()));
RetNH.getNode()->setReadMarker();
return true;
} else if (F->getName() == "llva_ipush_function0" ||
F->getName() == "llva_ipush_function1" ||
F->getName() == "llva_ipush_function3" ||
F->getName() == "llva_push_function1") {
DSNodeHandle RetNH = getValueDest(**(CS.arg_begin()));
DSNodeHandle FP = getValueDest(**(CS.arg_begin() + 1));
RetNH.getNode()->setModifiedMarker()->setReadMarker()->foldNodeCompletely();
RetNH.addEdgeTo(FP);
return true;
} else if (F->getName() == "llva_push_syscall" ) {
DSNodeHandle RetNH = getValueDest(**(CS.arg_begin() + 1));
DSNodeHandle FP = getValueDest(**(CS.arg_begin() + 2));
RetNH.getNode()->setModifiedMarker()->setReadMarker()->foldNodeCompletely();
RetNH.addEdgeTo(FP);
return true;
} else if (F->getName() == "llva_config_ldt" ||
F->getName() == "llva_mm_flush_tlb" ||
F->getName() == "llva_register_syscall_cleaner") {
return true;
} else if (F->getName() == "llva_iset_privileged") {
DSNodeHandle RetNH = getValueDest(**(CS.arg_begin()));
RetNH.getNode()->setModifiedMarker();
return true;
} else if (F->getName() == "llva_load_invoke") {
Value* GV = F->getParent()->getNamedGlobal("llva.invoke");
DSNodeHandle Dest = getValueDest(*GV);
Dest.getNode()->setModifiedMarker();
Dest.getNode()->mergeTypeInfo((*CS.arg_begin())->getType(), Dest.getOffset());
Dest.addEdgeTo(getValueDest(**CS.arg_begin()));
return true;
} else if (F->getName() == "llva_save_invoke") {
Value* GV = F->getParent()->getNamedGlobal("llva.invoke");
DSNodeHandle Ptr = getValueDest(*GV);
if (Ptr.isNull())
Ptr = createNode();
Ptr.getNode()->setReadMarker();
Ptr.getNode()->mergeTypeInfo(CS.getInstruction()->getType(), Ptr.getOffset(), false);
setDestTo(*CS.getInstruction(), getLink(Ptr));
return true;
} else if (F->getName() == "llva_mm_load_pgtable") {
Value* GV = F->getParent()->getNamedGlobal("llva.pgtable");
DSNodeHandle Dest = getValueDest(*GV);
Dest.getNode()->setModifiedMarker();
Dest.getNode()->mergeTypeInfo((*CS.arg_begin())->getType(), Dest.getOffset());
Dest.addEdgeTo(getValueDest(**CS.arg_begin()));
return true;
} else if (F->getName() == "llva_mm_save_pgtable") {
Value* GV = F->getParent()->getNamedGlobal("llva.pgtable");
DSNodeHandle Ptr = getValueDest(*GV);
if (Ptr.isNull())
Ptr = createNode();
Ptr.getNode()->setReadMarker();
Ptr.getNode()->mergeTypeInfo(CS.getInstruction()->getType(), Ptr.getOffset(), false);
setDestTo(*CS.getInstruction(), getLink(Ptr));
return true;
} else if (F->getName() == "llva_load_kstackp") {
Value* GV = F->getParent()->getNamedGlobal("llva.kstackp");
DSNodeHandle Dest = getValueDest(*GV);
Dest.getNode()->setModifiedMarker();
Dest.getNode()->mergeTypeInfo((*CS.arg_begin())->getType(), Dest.getOffset());
Dest.addEdgeTo(getValueDest(**CS.arg_begin()));
return true;
} else if (F->getName() == "llva_save_kstackp") {
Value* GV = F->getParent()->getNamedGlobal("llva.kstackp");
DSNodeHandle Ptr = getValueDest(*GV);
if (Ptr.isNull())
Ptr = createNode();
Ptr.getNode()->setReadMarker();
Ptr.getNode()->mergeTypeInfo(CS.getInstruction()->getType(), Ptr.getOffset(), false);
setDestTo(*CS.getInstruction(), getLink(Ptr));
return true;
} else if (F->getName() == "llva_icontext_save_retvalue") {
DSNodeHandle RetNH = getValueDest(**(CS.arg_begin()));
RetNH.getNode()->setModifiedMarker();
return true;
} else if (F->getName() == "llva_icontext_load_retvalue" ||
F->getName() == "llva_icontext_lif") {
DSNodeHandle RetNH = getValueDest(**(CS.arg_begin()));
RetNH.getNode()->setReadMarker();
return true;
} else if (F->getName() == "llva_invokestrnlen") {
DSNodeHandle RetNH = getValueDest(**(CS.arg_begin()));
RetNH.getNode()->setReadMarker();
return true;
} else if (F->getName() == "llva_unwind") {
DSNodeHandle RetNH = getValueDest(**(CS.arg_begin()));
RetNH.getNode()->setModifiedMarker();
return true;
} else if (F->getName() == "llva_set_integer_stackp") {
DSNodeHandle RetNH = getValueDest(**(CS.arg_begin()));
RetNH.getNode()->setModifiedMarker();
return true;
} else if (F->getName() == "llva_strcpy" ||
F->getName() == "llva_strncpy" ||
F->getName() == "llva_invokestrncpy") {
//This might be making unsafe assumptions about usage
//Merge return and first arg
DSNodeHandle RetNH = getValueDest(*CS.getInstruction());
RetNH.mergeWith(getValueDest(**CS.arg_begin()));
if (DSNode *N = RetNH.getNode())
N->setHeapNodeMarker()->setModifiedMarker();
//and read second pointer
if (DSNode *N = getValueDest(**(CS.arg_begin() + 1)).getNode())
N->setReadMarker();
return true;
} else if (F->getName() == "pchk_drop_slab" ||
F->getName() == "pchk_drop_obj" ||
F->getName() == "pchk_drop_pool" ||
F->getName() == "pchk_reg_obj" ||
F->getName() == "pchk_reg_slab" ||
F->getName() == "llva_assert_match_sig") {
return true;
} else if (F->getName() == "llva_save_fp" ||
F->getName() == "llva_save_integer") {
DSNodeHandle Ptr = getValueDest(**CS.arg_begin());
Ptr.getNode()->setModifiedMarker();
return true;
} else if (F->getName() == "llva_load_fp" ||
F->getName() == "llva_load_integer" ||
F->getName() == "llva_get_eip") {
DSNodeHandle Ptr = getValueDest(**CS.arg_begin());
Ptr.getNode()->setReadMarker();
return true;
} else if (F->getName() == "llva_save_icontext") {
DSNodeHandle Ptr = getValueDest(**CS.arg_begin());
Ptr.getNode()->setReadMarker();
Ptr = getValueDest(**(CS.arg_begin() + 1));
Ptr.getNode()->setModifiedMarker();
return true;
} else if (F->getName() == "llva_load_icontext") {
DSNodeHandle Ptr = getValueDest(**CS.arg_begin());
Ptr.getNode()->setModifiedMarker();
Ptr = getValueDest(**(CS.arg_begin() + 1));
Ptr.getNode()->setReadMarker();
return true;
} else if (F->getName() == "llva_register_syscall" ||
F->getName() == "llva_register_interrupt" ||
F->getName() == "llva_register_general_exception" ||
F->getName() == "llva_register_memory_exception") {
//FIXME: track functions and clear Incomplete flags on them
// or set userspace flag on pointers
return true;
} else if (F->getName() == "llva_readiob" ||
F->getName() == "llva_readioh" ||
F->getName() == "llva_readiow") {
DSNodeHandle Ptr = getValueDest(**CS.arg_begin());
if (Ptr.isNull()) Ptr = createNode();
Ptr.getNode()->setReadMarker();
Type* T = 0;
if (F->getName() == "llva_readiob") T = Type::SByteTy;
if (F->getName() == "llva_readioh") T = Type::ShortTy;
if (F->getName() == "llva_readiow") T = Type::IntTy;
Ptr.getNode()->mergeTypeInfo(T, Ptr.getOffset(), false);
return true;
} else if (F->getName() == "llva_writeiob" ||
F->getName() == "llva_writeioh" ||
F->getName() == "llva_writeiow") {
DSNodeHandle Ptr = getValueDest(**CS.arg_begin());
if (Ptr.isNull()) Ptr = createNode();
Ptr.getNode()->setModifiedMarker();
Type* T = 0;
if (F->getName() == "llva_writeiob") T = Type::SByteTy;
if (F->getName() == "llva_writeioh") T = Type::ShortTy;
if (F->getName() == "llva_writeiow") T = Type::IntTy;
Ptr.getNode()->mergeTypeInfo(T, Ptr.getOffset(), false);
return true;
} else if (F->getName() == "llva_atomic_compare_and_swap" ||
F->getName() == "llva_atomic_compare_and_swap_p" ||
F->getName() == "llva_atomic_cas_lw" ||
F->getName() == "llva_atomic_cas_h" ||
F->getName() == "llva_atomic_cas_b" ||
F->getName() == "llva_atomic_fetch_add_store" ||
F->getName() == "llva_atomic_and" ||
F->getName() == "llva_atomic_or") {
DSNodeHandle Ptr = getValueDest(**CS.arg_begin());
if (Ptr.isNull()) Ptr = createNode();
Ptr.getNode()->setReadMarker();
Type* T = Type::IntTy;
if (F->getName() == "llva_atomic_cas_b") T = Type::SByteTy;
if (F->getName() == "llva_atomic_cas_h") T = Type::ShortTy;
Ptr.getNode()->mergeTypeInfo(T, Ptr.getOffset(), false);
return true;
} else if (F->getName() == "llva_save_tsc" || F->getName() == "llva_load_tsc") {
return true;
} else if (F->getName() == "llva_ialloca") {
DSNodeHandle RetNH = getValueDest(*CS.getInstruction());
RetNH.mergeWith(getValueDest(**CS.arg_begin()));
RetNH.getNode()->setModifiedMarker()->setReadMarker()->foldNodeCompletely();
return true;
} else if (F->getName() == "llva_ipop_function0") {
// Mark the memory modified.
if (DSNode *N = getValueDest(**CS.arg_begin()).getNode())
N->setModifiedMarker()->setReadMarker();
return true;
} else if (F->getName() == "llva_init_icontext") {
DSNodeHandle RetNH = getValueDest(*CS.getInstruction());
RetNH.mergeWith(getValueDest(**(CS.arg_begin() + 1)));
RetNH.getNode()->setModifiedMarker()->foldNodeCompletely();
if (DSNode *N = getValueDest(**CS.arg_begin()).getNode())
N->setReadMarker();
return true;
} else if (F->getName() == "llva_was_privileged") {
if (DSNode *N = getValueDest(**CS.arg_begin()).getNode())
N->setReadMarker();
return true;
} else if (F->getName() == "llva_clear_icontext") {
// Mark the memory modified.
if (DSNode *N = getValueDest(**CS.arg_begin()).getNode())
N->setModifiedMarker();
return true;
} else if (F->getName() == "llva_memset" ||
F->getName() == "llva_invokememset") {
// Mark the memory modified.
if (DSNode *N = getValueDest(**CS.arg_begin()).getNode())
N->setModifiedMarker();
return true;
} else if (F->getName() == "llva_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 true;
} else if (F->getName() == "llva_invokememcpy") {
//Find types
const Type* T1 = CS.getInstruction()->getOperand(1)->getType();
const Type* T2 = CS.getInstruction()->getOperand(2)->getType();
if (CastInst* CI1 = dyn_cast<CastInst>(CS.getInstruction()->getOperand(1)))
T1 = CI1->getOperand(0)->getType();
if (CastInst* CI2 = dyn_cast<CastInst>(CS.getInstruction()->getOperand(2)))
T2 = CI2->getOperand(0)->getType();
if (const PointerType* P1 = dyn_cast<PointerType>(T1))
T1 = P1->getElementType();
if (const PointerType* P2 = dyn_cast<PointerType>(T2))
T2 = P2->getElementType();
uint64_t len = 0;
if (ConstantInt* CI = dyn_cast<ConstantInt>(CS.getInstruction()->getOperand(3)))
len = CI->getZExtValue();
DSNodeHandle NH1 = getValueDest(**CS.arg_begin());
DSNodeHandle NH2 = getValueDest(**(CS.arg_begin()+1));
const TargetData &TD = NH1.getNode()->getTargetData();
const Type* TTU = T1;
bool isArray = false;
if (isa<StructType>(T1) && TD.getTypeSize(T1) >= TD.getTypeSize(T2))
TTU = T1;
else if (isa<StructType>(T2))
TTU = T2;
else
isArray = true;
if (TD.getTypeSize(TTU) < len)
isArray = true;
if (NH1.getNode()->getType() == Type::VoidTy)
NH1.getNode()->mergeTypeInfo(TTU, NH1.getOffset(), false);
if (NH2.getNode()->getType() == Type::VoidTy)
NH2.getNode()->mergeTypeInfo(TTU, NH2.getOffset(), false);
if (isArray) {
NH1.getNode()->setArrayMarker();
NH2.getNode()->setArrayMarker();
}
NH1.getNode()->mergeTypeInfo(TTU, NH1.getOffset(), false);
NH2.getNode()->mergeTypeInfo(TTU, NH2.getOffset(), false);
NH1.getNode()->setModifiedMarker();
NH2.getNode()->setReadMarker();
for (unsigned i = 0; i < len / 4; ++i) {
int x = NH1.getNode()->isArray() ? 0 : (NH1.getOffset() / 4 + i);
int y = NH2.getNode()->isArray() ? 0 : (NH2.getOffset() / 4 + i);
NH1.getNode()->getLink(x*4).mergeWith(NH2.getNode()->getLink(y*4));
}
#if 0
// 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();
#endif
return true;
} else if (F->getName() == "llva_save_stackp" ||
F->getName() == "llvm.returnaddress") {
// Create a new DSNode for the memory returned by llva_save_stackp()
DSNodeHandle RetNH = getValueDest(*CS.getInstruction());
RetNH.getNode()->setAllocaNodeMarker();
RetNH.getNode()->setUnknownNodeMarker();
RetNH.getNode()->foldNodeCompletely();
return true;
} else if (F->getName() == "llva_get_icontext_stackp") {
// Create a new DSNode for the memory returned by llva_save_stackp()
DSNodeHandle RetNH = getValueDest(*CS.getInstruction());
// RetNH.getNode()->setAllocaNodeMarker();
// RetNH.getNode()->setUnknownNodeMarker();
// RetNH.getNode()->foldNodeCompletely();
if (DSNode *N = getValueDest(**CS.arg_begin()).getNode())
N->setReadMarker();
return true;
} else if (F->getName() == "llva_set_icontext_stackp") {
DSNodeHandle Dest = getValueDest(**CS.arg_begin());
// Mark that the node is written to...
Dest.getNode()->setModifiedMarker();
Dest.getNode()->foldNodeCompletely();
getLink(Dest).mergeWith(getValueDest(**(CS.arg_begin() + 1)));
return true;
#if 0
} else if (F->getName() == "__generic_copy_from_user") {
if (CS.getCaller()->getName() == "kmem_cache_alloc")
return false;
// 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 true;
#endif
#endif
}
return false;
}
void GraphBuilder::visitCallSite(CallSite CS) {
Value *Callee = CS.getCalledValue();
bool isSyscall6 = false;
if (Function *F = dyn_cast<Function>(Callee)) {
// Determine if the called function is one of the specified heap
// allocation functions
if (AllocList.end() != std::find(AllocList.begin(), AllocList.end(), F->getName())) {
DSNodeHandle RetNH;
RetNH = getValueDest(*CS.getInstruction());
RetNH.getNode()->setHeapNodeMarker()->setModifiedMarker();
RetNH.getNode()->getMP()->addCallSite(CS);
//
// Anything that is not a pool allocator must mark objects as
// type-unknown.
//
if (F->getName() != "kmem_cache_alloc")
RetNH.getNode()->foldNodeCompletely();
return;
}
#ifdef SVA_IO
//
// Determine whether this is a call to a function that allocates an I/O
// object. If so, then make it with the I/O flags and make it
// type-unknown (as the I/O device may treat the memory as a type different
// than what we infer).
//
if (IOAllocList.end() != std::find(IOAllocList.begin(), IOAllocList.end(), F->getName())) {
DSNodeHandle RetNH;
if (F->getName() == "pseudo_alloc")
RetNH = getValueDest(**CS.arg_begin());
else
RetNH = getValueDest(*CS.getInstruction());
RetNH.getNode()->setIONodeMarker()->setModifiedMarker();
RetNH.getNode()->getMP()->addCallSite(CS);
RetNH.getNode()->foldNodeCompletely();
return;
}
#endif
// Determine if the called function is one of the specified heap
// free functions
if (FreeList.end() != std::find(FreeList.begin(), FreeList.end(),
F->getName())) {
// Mark that the node is written to...
if (DSNode *N = getValueDest(*(CS.getArgument(0))).getNode())
N->setModifiedMarker()->setHeapNodeMarker();
return;
}
if (F->getName() == "llva_syscall6")
isSyscall6 = true;
if (F->isExternal()) {
if (F->isIntrinsic() && visitIntrinsic(CS, F))
return;
if (visitExternal(CS,F))
return;
if (!isSyscall6) {
// 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";
}
}
}
}
#ifdef LLVA_KERNEL
if (isSyscall6) {
assert (isa<ConstantInt>(CS.getArgument(0)) && "llva_syscall6 called with non-const argument");
ConstantInt * C = dyn_cast<ConstantInt>(CS.getArgument(0));
Callee = syscalls[C->getSExtValue()];
assert (Callee && "llva_syscall: No target for system call vector");
}
#endif
// Set up the return value...
DSNodeHandle RetVal;
Instruction *I = CS.getInstruction();
if (isPointerType(I->getType()))
RetVal = getValueDest(*I);
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());
// 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 (CalleeNode)
FunctionCalls->push_back(DSCallSite(CS, RetVal, CalleeNode, Args));
else
FunctionCalls->push_back(DSCallSite(CS, RetVal, cast<Function>(Callee),
Args));
}
void GraphBuilder::visitFreeInst(FreeInst &FI) {
// Mark that the node is written to...
if (DSNode *N = getValueDest(*FI.getOperand(0)).getNode())
N->setModifiedMarker()->setHeapNodeMarker();
}
/// Handle casts...
void GraphBuilder::visitCastInst(CastInst &CI) {
if (isPointerType(CI.getType()))
if (isPointerType(CI.getOperand(0)->getType())) {
DSNodeHandle Ptr = getValueDest(*CI.getOperand(0));
if (Ptr.getNode() == 0) return;
// Cast one pointer to the other, just act like a copy instruction
setDestTo(CI, Ptr);
} 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.
//
//Try to track all values of ints back to constants or valid pointers
std::set<Value*> sources;
if (getSourcePointerValues(CI.getOperand(0), sources)) {
setDestTo(CI, createNode());
for (std::set<Value*>::iterator ii = sources.begin(), ee = sources.end();
ii != ee; ++ii)
getValueDest(CI).mergeWith(getValueDest(**ii));
} else {
if (DebugUnknown) {
std::cerr << "In " << CI.getParent()->getParent()->getName() << " ";
CI.dump();
}
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 (DSNode *N = CurNode.getNode()) {
if (DebugUnknown) {
std::cerr << "In " << Inst.getParent()->getParent()->getName() << " ";
Inst.dump();
}
N->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...
DSNode *NHN = NH.getNode();
NHN->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) {
DSNode *NHN = NH.getNode();
//Some programmers think ending a structure with a [0 x sbyte] is cute
if (SL->MemberOffsets[i] < SL->StructSize) {
DSNodeHandle NewNH(NHN, NH.getOffset()+(unsigned)SL->MemberOffsets[i]);
MergeConstantInitIntoNode(NewNH, cast<Constant>(CS->getOperand(i)));
} else if (SL->MemberOffsets[i] == SL->StructSize) {
DEBUG(std::cerr << "Zero size element at end of struct\n");
NHN->foldNodeCompletely();
} else {
assert(0 && "type was smaller than offsets of of struct layout indicate");
}
}
} else if (isa<ConstantAggregateZero>(C) || isa<UndefValue>(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());
NH.getNode()->getMP()->addGlobal(GV);
}
/// BuildGlobalECs - Look at all of the nodes in the globals graph. If any node
/// contains multiple globals, DSA will never, ever, be able to tell the globals
/// apart. Instead of maintaining this information in all of the graphs
/// throughout the entire program, store only a single global (the "leader") in
/// the graphs, and build equivalence classes for the rest of the globals.
static void BuildGlobalECs(DSGraph &GG, std::set<GlobalValue*> &ECGlobals) {
DSScalarMap &SM = GG.getScalarMap();
EquivalenceClasses<GlobalValue*> &GlobalECs = SM.getGlobalECs();
for (DSGraph::node_iterator I = GG.node_begin(), E = GG.node_end();
I != E; ++I) {
if (I->getGlobalsList().size() <= 1) continue;
// First, build up the equivalence set for this block of globals.
const std::vector<GlobalValue*> &GVs = I->getGlobalsList();
GlobalValue *First = GVs[0];
for (unsigned i = 1, e = GVs.size(); i != e; ++i)
GlobalECs.unionSets(First, GVs[i]);
// Next, get the leader element.
assert(First == GlobalECs.getLeaderValue(First) &&
"First did not end up being the leader?");
// Next, remove all globals from the scalar map that are not the leader.
assert(GVs[0] == First && "First had to be at the front!");
for (unsigned i = 1, e = GVs.size(); i != e; ++i) {
ECGlobals.insert(GVs[i]);
SM.erase(SM.find(GVs[i]));
}
// Finally, change the global node to only contain the leader.
I->clearGlobals();
I->addGlobal(First);
}
DEBUG(GG.AssertGraphOK());
}
/// EliminateUsesOfECGlobals - Once we have determined that some globals are in
/// really just equivalent to some other globals, remove the globals from the
/// specified DSGraph (if present), and merge any nodes with their leader nodes.
static void EliminateUsesOfECGlobals(DSGraph &G,
const std::set<GlobalValue*> &ECGlobals) {
DSScalarMap &SM = G.getScalarMap();
EquivalenceClasses<GlobalValue*> &GlobalECs = SM.getGlobalECs();
bool MadeChange = false;
for (DSScalarMap::global_iterator GI = SM.global_begin(), E = SM.global_end();
GI != E; ) {
GlobalValue *GV = *GI++;
if (!ECGlobals.count(GV)) continue;
const DSNodeHandle &GVNH = SM[GV];
assert(!GVNH.isNull() && "Global has null NH!?");
// Okay, this global is in some equivalence class. Start by finding the
// leader of the class.
GlobalValue *Leader = GlobalECs.getLeaderValue(GV);
// If the leader isn't already in the graph, insert it into the node
// corresponding to GV.
if (!SM.global_count(Leader)) {
GVNH.getNode()->addGlobal(Leader);
SM[Leader] = GVNH;
} else {
// Otherwise, the leader is in the graph, make sure the nodes are the
// merged in the specified graph.
const DSNodeHandle &LNH = SM[Leader];
if (LNH.getNode() != GVNH.getNode())
LNH.mergeWith(GVNH);
}
// Next step, remove the global from the DSNode.
GVNH.getNode()->removeGlobal(GV);
// Finally, remove the global from the ScalarMap.
SM.erase(GV);
MadeChange = true;
}
DEBUG(if(MadeChange) G.AssertGraphOK());
}
bool LocalDataStructures::runOnModule(Module &M) {
#ifdef LLVA_KERNEL
#if 0
AllocList.push_back("kmalloc");
#endif
AllocList.push_back("__vmalloc");
AllocList.push_back("kmem_cache_alloc");
AllocList.push_back("__alloc_bootmem");
AllocList.push_back("__get_free_pages");
AllocList.push_back("pseudo_alloc");
AllocList.push_back("malloc");
#ifdef SVA_IO
IOAllocList.push_back("__ioremap");
IOAllocList.push_back("ioremap_nocache");
#endif
#if 0
FreeList.push_back("kfree");
#endif
FreeList.push_back("vfree");
FreeList.push_back("free_pages");
FreeList.push_back("kmem_cache_free");
FreeList.push_back("pseudo_free");
FreeList.push_back("free");
//figure out all system call numbers
Function* lrs = M.getNamedFunction("llva_register_syscall");
if (lrs)
for (Value::use_iterator ii = lrs->use_begin(), ee = lrs->use_end(); ii != ee; ++ii)
if (CallInst* CI = dyn_cast<CallInst>(*ii))
if ((CI->getCalledFunction() == lrs) && (isa<ConstantInt>(CI->getOperand(1)))) {
ConstantInt * CNum = dyn_cast<ConstantInt>(CI->getOperand(1));
unsigned int num = CNum->getSExtValue();
Value* fun = CI->getOperand(2);
if (ConstantExpr* CE = dyn_cast<ConstantExpr>(fun))
if (CE->getOpcode() == Instruction::Cast)
fun = CE->getOperand(0);
if (Function* F = dyn_cast<Function>(fun))
syscalls[num] = F;
}
//Add shadow globals for processor state
new GlobalVariable(PointerType::get(Type::SByteTy), false, GlobalValue::InternalLinkage, Constant::getNullValue(PointerType::get(Type::SByteTy)), "llva.pgtable", &M);
new GlobalVariable(PointerType::get(Type::SByteTy), false, GlobalValue::InternalLinkage, Constant::getNullValue(PointerType::get(Type::SByteTy)), "llva.invoke", &M);
new GlobalVariable(PointerType::get(Type::SByteTy), false, GlobalValue::InternalLinkage, Constant::getNullValue(PointerType::get(Type::SByteTy)), "llva.kstackp", &M);
#endif
const TargetData &TD = getAnalysis<TargetData>();
// First step, build the globals graph.
GlobalsGraph = new DSGraph(GlobalECs, TD);
{
GraphBuilder GGB(*GlobalsGraph);
// Add initializers for all of the globals to the globals graph.
for (Module::global_iterator I = M.global_begin(), E = M.global_end();
I != E; ++I)
if (!I->isExternal() && I->getName() != "llvm.used")
GGB.mergeInGlobalInitializer(I);
}
// Next step, iterate through the nodes in the globals graph, unioning
// together the globals into equivalence classes.
std::set<GlobalValue*> ECGlobals;
BuildGlobalECs(*GlobalsGraph, ECGlobals);
DEBUG(std::cerr << "Eliminating " << ECGlobals.size() << " EC Globals!\n");
ECGlobals.clear();
// 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(GlobalECs, TD, *I,
GlobalsGraph)));
GlobalsGraph->removeTriviallyDeadNodes();
GlobalsGraph->markIncompleteNodes(DSGraph::MarkFormalArgs);
// Now that we've computed all of the graphs, and merged all of the info into
// the globals graph, see if we have further constrained the globals in the
// program if so, update GlobalECs and remove the extraneous globals from the
// program.
BuildGlobalECs(*GlobalsGraph, ECGlobals);
if (!ECGlobals.empty()) {
DEBUG(std::cerr << "Eliminating " << ECGlobals.size() << " EC Globals!\n");
for (hash_map<Function*, DSGraph*>::iterator I = DSInfo.begin(),
E = DSInfo.end(); I != E; ++I)
EliminateUsesOfECGlobals(*I->second, ECGlobals);
}
return true;
}
// releaseMemory - If the pass pipeline is done with this pass, we can release
// our memory... here...
//
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;
}