//===- 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
//
//===----------------------------------------------------------------------===//
-#include "llvm/Analysis/DataStructure.h"
-#include "llvm/Analysis/DSGraph.h"
+#include "llvm/Analysis/DataStructure/DataStructure.h"
+#include "llvm/Analysis/DataStructure/DSGraph.h"
#include "llvm/Constants.h"
#include "llvm/DerivedTypes.h"
#include "llvm/Instructions.h"
#include "llvm/Support/GetElementPtrTypeIterator.h"
#include "llvm/Support/InstVisitor.h"
#include "llvm/Target/TargetData.h"
-#include "Support/CommandLine.h"
-#include "Support/Debug.h"
-#include "Support/Timer.h"
+#include "llvm/Support/CommandLine.h"
+#include "llvm/Support/Debug.h"
+#include "llvm/Support/Timer.h"
// FIXME: This should eventually be a FunctionPass that is automatically
// aggregated into a Pass.
using namespace llvm;
-static RegisterAnalysis<LocalDataStructures>
+static RegisterPass<LocalDataStructures>
X("datastructure", "Local Data Structure Analysis");
static cl::opt<bool>
-TrackIntegersAsPointers("dsa-track-integers",
+TrackIntegersAsPointers("dsa-track-integers", cl::Hidden,
cl::desc("If this is set, track integers as potential pointers"));
-
+
+static cl::opt<bool>
+IgnoreSetCC("dsa-ignore-setcc", cl::Hidden,
+ cl::desc("If this is set, do nothing at pointer comparisons"));
+
+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>
+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 {
DSGraph &G;
DSNodeHandle *RetNode; // Node that gets returned...
DSScalarMap &ScalarMap;
- std::vector<DSCallSite> *FunctionCalls;
+ std::list<DSCallSite> *FunctionCalls;
public:
- GraphBuilder(Function &f, DSGraph &g, DSNodeHandle &retNode,
- std::vector<DSCallSite> &fc)
+ GraphBuilder(Function &f, DSGraph &g, DSNodeHandle &retNode,
+ std::list<DSCallSite> &fc)
: G(g), RetNode(&retNode), ScalarMap(G.getScalarMap()),
FunctionCalls(&fc) {
// Create scalar nodes for all pointer arguments...
- for (Function::aiterator I = f.abegin(), E = f.aend(); I != E; ++I)
+ for (Function::arg_iterator I = f.arg_begin(), E = f.arg_end();
+ I != E; ++I)
if (isPointerType(I->getType()))
getValueDest(*I);
void handleAlloc(AllocationInst &AI, bool isHeap);
void visitPHINode(PHINode &PN);
+ void visitSelectInst(SelectInst &SI);
void visitGetElementPtrInst(User &GEP);
void visitReturnInst(ReturnInst &RI);
void visitStoreInst(StoreInst &SI);
void visitCallInst(CallInst &CI);
void visitInvokeInst(InvokeInst &II);
- void visitSetCondInst(SetCondInst &SCI) {} // SetEQ & friends are ignored
+ 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:
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;
///
void setDestTo(Value &V, const DSNodeHandle &NH);
- /// getValueDest - Return the DSNode that the actual value points to.
+ /// getValueDest - Return the DSNode that the actual value points to.
///
DSNodeHandle getValueDest(Value &V);
//===----------------------------------------------------------------------===//
// DSGraph constructor - Simply use the GraphBuilder to construct the local
// graph.
-DSGraph::DSGraph(const TargetData &td, Function &F, DSGraph *GG)
- : GlobalsGraph(GG), TD(td) {
+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");
+ DOUT << " [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);
Timer::addPeakMemoryMeasurement();
#endif
- // Remove all integral constants from the scalarmap!
- for (DSScalarMap::iterator I = ScalarMap.begin(); I != ScalarMap.end();)
- if (isa<ConstantIntegral>(I->first))
- ScalarMap.erase(I++);
- else
- ++I;
+ // If there are any constant globals referenced in this function, merge their
+ // initializers into the local graph from the globals graph.
+ if (ScalarMap.global_begin() != ScalarMap.global_end()) {
+ ReachabilityCloner RC(*this, *GG, 0);
+
+ for (DSScalarMap::global_iterator I = ScalarMap.global_begin();
+ I != ScalarMap.global_end(); ++I)
+ if (GlobalVariable *GV = dyn_cast<GlobalVariable>(*I))
+ if (!GV->isExternal() && GV->isConstant())
+ RC.merge(ScalarMap[GV], GG->ScalarMap[GV]);
+ }
markIncompleteNodes(DSGraph::MarkFormalArgs);
///
DSNodeHandle GraphBuilder::getValueDest(Value &Val) {
Value *V = &Val;
- if (V == Constant::getNullValue(V->getType()))
+ 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.getNode())
+ 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.
- 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) {
+ DSNode* N;
+ if (GlobalValue* GV = dyn_cast<GlobalValue>(V)) {
+ // Create a new global node for this global variable.
+ N = createNode(GV->getType()->getElementType());
+ N->addGlobal(GV);
+ } else if (Constant *C = dyn_cast<Constant>(V)) {
+ if (ConstantExpr *CE = dyn_cast<ConstantExpr>(C)) {
+ if (CE->isCast()) {
+ if (isa<PointerType>(CE->getOperand(0)->getType()))
+ NH = getValueDest(*CE->getOperand(0));
+ else
+ NH = createNode()->setUnknownNodeMarker();
+ } else if (CE->getOpcode() == Instruction::GetElementPtr) {
visitGetElementPtrInst(*CE);
DSScalarMap::iterator I = ScalarMap.find(CE);
assert(I != ScalarMap.end() && "GEP didn't get processed right?");
// This returns a conservative unknown node for any unhandled ConstExpr
return NH = createNode()->setUnknownNodeMarker();
}
- if (NH.getNode() == 0) { // (getelementptr null, X) returns null
+ if (NH.isNull()) { // (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 if (isa<UndefValue>(C)) {
+ ScalarMap.erase(V);
+ return 0;
} else {
assert(0 && "Unknown constant type!");
}
-
- // Otherwise we need to create a new node to point to...
- DSNode *N;
- if (GlobalValue *GV = dyn_cast<GlobalValue>(V)) {
- // Create a new global node for this global variable...
- N = createNode(GV->getType()->getElementType());
- N->addGlobal(GV);
+ N = createNode(); // just create a shadow node
} else {
// Otherwise just create a shadow node
N = createNode();
}
- NH.setNode(N); // Remember that we are pointing to it...
- NH.setOffset(0);
+ NH.setTo(N, 0); // Remember that we are pointing to it...
return NH;
}
DSNodeHandle &GraphBuilder::getLink(const DSNodeHandle &node, unsigned LinkNo) {
DSNodeHandle &Node = const_cast<DSNodeHandle&>(node);
DSNodeHandle &Link = Node.getLink(LinkNo);
- if (!Link.getNode()) {
+ if (Link.isNull()) {
// If the link hasn't been created yet, make and return a new shadow node
Link = createNode();
}
/// merge the two destinations together.
///
void GraphBuilder::setDestTo(Value &V, const DSNodeHandle &NH) {
- DSNodeHandle &AINH = ScalarMap[&V];
- if (AINH.getNode() == 0) // Not pointing to anything yet?
- AINH = NH; // Just point directly to NH
- else
- AINH.mergeWith(NH);
+ ScalarMap[&V].mergeWith(NH);
}
PNDest.mergeWith(getValueDest(*PN.getIncomingValue(i)));
}
+void GraphBuilder::visitSelectInst(SelectInst &SI) {
+ if (!isPointerType(SI.getType())) return; // Only pointer Selects
+
+ DSNodeHandle &Dest = ScalarMap[&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
+ if(!IgnoreSetCC)
+ ScalarMap[SCI.getOperand(0)].mergeWith(getValueDest(*SCI.getOperand(1)));
+}
+
+
void GraphBuilder::visitGetElementPtrInst(User &GEP) {
DSNodeHandle Value = getValueDest(*GEP.getOperand(0));
- if (Value.getNode() == 0) return;
+ 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).
// If all of the indices are zero, the result points to the operand without
// applying the type.
- if (AllZeros) {
+ if (AllZeros || (!Value.isNull() &&
+ Value.getNode()->isNodeCompletelyFolded())) {
setDestTo(GEP, Value);
return;
}
#if 0
// Handle the pointer index specially...
if (GEP.getNumOperands() > 1 &&
- GEP.getOperand(1) != ConstantSInt::getNullValue(Type::LongTy)) {
+ (!isa<Constant>(GEP.getOperand(1)) ||
+ !cast<Constant>(GEP.getOperand(1))->isNullValue())) {
// If we already know this is an array being accessed, don't do anything...
if (!TopTypeRec.isArray) {
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];
+ 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 (ConstantSInt *CS = dyn_cast<ConstantSInt>(GEP.getOperand(i))) {
- Offset += CS->getValue()*TD.getTypeSize(CurTy);
+ 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";
+ llvm_cerr << "Pointer indexing not handled yet!\n";
else {
const ArrayType *ATy = cast<ArrayType>(STy);
unsigned ElSize = TD.getTypeSize(CurTy);
// Add in the offset calculated...
Value.setOffset(Value.getOffset()+Offset);
- // Value is now the pointer we want to GEP to be...
+ // 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);
}
void GraphBuilder::visitLoadInst(LoadInst &LI) {
DSNodeHandle Ptr = getValueDest(*LI.getOperand(0));
- if (Ptr.getNode() == 0) return;
+ if (Ptr.isNull())
+ Ptr = createNode();
// Make that the node is read from...
Ptr.getNode()->setReadMarker();
void GraphBuilder::visitStoreInst(StoreInst &SI) {
const Type *StoredTy = SI.getOperand(0)->getType();
DSNodeHandle Dest = getValueDest(*SI.getOperand(1));
- if (Dest.getNode() == 0) return;
+ if (Dest.isNull()) return;
// Mark that the node is written to...
Dest.getNode()->setModifiedMarker();
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);
}
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:
+ DOUT << "[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;
+ }
+ return false;
+}
+
void GraphBuilder::visitCallSite(CallSite CS) {
+ Value *Callee = CS.getCalledValue();
+
// Special case handling of certain libc allocation functions here.
- if (Function *F = CS.getCalledFunction())
+ if (Function *F = dyn_cast<Function>(Callee))
if (F->isExternal())
- switch (F->getIntrinsicID()) {
- case Intrinsic::memmove:
- case Intrinsic::memcpy: {
- // Merge the first & second arguments, and mark the memory read and
- // modified.
- DSNodeHandle RetNH = getValueDest(**CS.arg_begin());
- RetNH.mergeWith(getValueDest(**(CS.arg_begin()+1)));
- if (DSNode *N = RetNH.getNode())
- N->setModifiedMarker()->setReadMarker();
+ if (F->isIntrinsic() && visitIntrinsic(CS, F))
return;
- }
- default:
- 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() == "bzero") {
- // Mark the memory modified.
- DSNodeHandle H = getValueDest(**CS.arg_begin());
- if (DSNode *N = H.getNode())
- N->setModifiedMarker();
- return;
+ else {
+ // Determine if the called function is one of the specified heap
+ // allocation functions
+ if (AllocList.end() != std::find(AllocList.begin(), AllocList.end(), F->getName())) {
+ setDestTo(*CS.getInstruction(),
+ createNode()->setHeapNodeMarker()->setModifiedMarker());
+ return;
+ }
+
+ // 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 (visitExternal(CS,F))
+ return;
+ // 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) {
+ DOUT << "WARNING: Call to unknown external function '"
+ << F->getName() << "' will cause pessimistic results!\n";
}
}
-
// Set up the return value...
DSNodeHandle RetVal;
Instruction *I = CS.getInstruction();
if (isPointerType(I->getType()))
RetVal = getValueDest(*I);
- DSNode *Callee = 0;
- if (DisableDirectCallOpt || !isa<Function>(CS.getCalledValue())) {
- Callee = getValueDest(*CS.getCalledValue()).getNode();
- if (Callee == 0) {
- std::cerr << "WARNING: Program is calling through a null pointer?\n"
- << *I;
+ DSNode *CalleeNode = 0;
+ if (DisableDirectCallOpt || !isa<Function>(Callee)) {
+ CalleeNode = getValueDest(*Callee).getNode();
+ if (CalleeNode == 0) {
+ llvm_cerr << "WARNING: Program is calling through a null pointer?\n"<< *I;
return; // Calling a null pointer?
}
}
Args.push_back(getValueDest(**I));
// Add a new function call entry...
- if (Callee)
- FunctionCalls->push_back(DSCallSite(CS, RetVal, Callee, Args));
+ if (CalleeNode)
+ FunctionCalls->push_back(DSCallSite(CS, RetVal, CalleeNode, Args));
else
- FunctionCalls->push_back(DSCallSite(CS, RetVal, CS.getCalledFunction(),
+ FunctionCalls->push_back(DSCallSite(CS, RetVal, cast<Function>(Callee),
Args));
}
void GraphBuilder::visitFreeInst(FreeInst &FI) {
// Mark that the node is written to...
- DSNode *N = getValueDest(*FI.getOperand(0)).getNode();
- N->setModifiedMarker();
- N->setHeapNodeMarker();
+ if (DSNode *N = getValueDest(*FI.getOperand(0)).getNode())
+ N->setModifiedMarker()->setHeapNodeMarker();
}
/// Handle casts...
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());
- }
+ // Pointers can only be cast with BitCast so check that the instruction
+ // is a BitConvert. If not, its guaranteed not to involve any pointers so
+ // we don't do anything.
+ switch (CI.getOpcode()) {
+ default: break;
+ case Instruction::BitCast:
+ case Instruction::IntToPtr:
+ 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.
+ setDestTo(CI, createNode()->setUnknownNodeMarker());
+ }
+ break;
+ }
}
if (isPointerType((*I)->getType()))
CurNode.mergeWith(getValueDest(**I));
- if (CurNode.getNode())
- CurNode.getNode()->setUnknownNodeMarker();
+ if (DSNode *N = CurNode.getNode())
+ N->setUnknownNodeMarker();
}
// pointed to by NH.
void GraphBuilder::MergeConstantInitIntoNode(DSNodeHandle &NH, Constant *C) {
// Ensure a type-record exists...
- NH.getNode()->mergeTypeInfo(C->getType(), NH.getOffset());
+ DSNode *NHN = NH.getNode();
+ NHN->mergeTypeInfo(C->getType(), NH.getOffset());
if (C->getType()->isFirstClassType()) {
if (isPointerType(C->getType()))
} 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)));
+ 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) {
+ DOUT << "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!");
}
}
-bool LocalDataStructures::run(Module &M) {
- GlobalsGraph = new DSGraph(getAnalysis<TargetData>());
+/// 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) {
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)));
+ // First step, build the globals graph.
+ GlobalsGraph = new DSGraph(GlobalECs, TD);
+ {
+ GraphBuilder GGB(*GlobalsGraph);
- 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())
+ GGB.mergeInGlobalInitializer(I);
+ }
- // Add initializers for all of the globals to the globals graph...
- for (Module::giterator I = M.gbegin(), E = M.gend(); I != E; ++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);
+ DOUT << "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())
- GGB.mergeInGlobalInitializer(I);
+ 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()) {
+ DOUT << "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 false;
}
projects / oota-llvm.git / blobdiff