void Preparer::expandCallSite(CallSite CS) {
if (!CS.getCalledFunction()) return;
Function *F = CS.getCalledFunction();
if (!F->isVarArg()) return;
vector<Value *> Args;
for (CallSite::arg_iterator ArgI = CS.arg_begin();
ArgI != CS.arg_end(); ArgI++) {
Args.push_back(*ArgI);
}
Args.push_back(ConstantInt::get(
IntegerType::get(CS.getInstruction()->getContext(), 8), 0));
string InstName = "";
if (CS.getInstruction()->getName() != "")
InstName = CS.getInstruction()->getName().str() + ".padded";
if (CallInst *CI = dyn_cast<CallInst>(CS.getInstruction())) {
CallInst *NewCI = CallInst::Create(F, Args, InstName, CI);
NewCI->setAttributes(CI->getAttributes());
CI->replaceAllUsesWith(NewCI);
CI->eraseFromParent();
} else if (InvokeInst *II = dyn_cast<InvokeInst>(CS.getInstruction())) {
InvokeInst *NewII = InvokeInst::Create(F,
II->getNormalDest(), II->getUnwindDest(), Args, InstName, II);
NewII->setAttributes(II->getAttributes());
II->replaceAllUsesWith(NewII);
II->eraseFromParent();
}
}
CallSite GNUstep::IMPCacher::SplitSend(CallSite msgSend)
{
BasicBlock *lookupBB = msgSend->getParent();
Function *F = lookupBB->getParent();
Module *M = F->getParent();
Function *send = M->getFunction("objc_msgSend");
Function *send_stret = M->getFunction("objc_msgSend_stret");
Function *send_fpret = M->getFunction("objc_msgSend_fpret");
Value *self;
Value *cmd;
int selfIndex = 0;
if ((msgSend.getCalledFunction() == send) ||
(msgSend.getCalledFunction() == send_fpret)) {
self = msgSend.getArgument(0);
cmd = msgSend.getArgument(1);
} else if (msgSend.getCalledFunction() == send_stret) {
selfIndex = 1;
self = msgSend.getArgument(1);
cmd = msgSend.getArgument(2);
} else {
abort();
return CallSite();
}
CGBuilder B(&F->getEntryBlock(), F->getEntryBlock().begin());
Value *selfPtr = B.CreateAlloca(self->getType());
B.SetInsertPoint(msgSend.getInstruction());
B.CreateStore(self, selfPtr, true);
LLVMType *impTy = msgSend.getCalledValue()->getType();
LLVMType *slotTy = PointerType::getUnqual(StructType::get(PtrTy, PtrTy, PtrTy,
IntTy, impTy, PtrTy, NULL));
Value *slot;
Constant *lookupFn = M->getOrInsertFunction("objc_msg_lookup_sender",
slotTy, selfPtr->getType(), cmd->getType(), PtrTy, NULL);
if (msgSend.isCall()) {
slot = B.CreateCall3(lookupFn, selfPtr, cmd, Constant::getNullValue(PtrTy));
} else {
InvokeInst *inv = cast<InvokeInst>(msgSend.getInstruction());
BasicBlock *callBB = SplitBlock(lookupBB, msgSend.getInstruction(), Owner);
removeTerminator(lookupBB);
B.SetInsertPoint(lookupBB);
slot = B.CreateInvoke3(lookupFn, callBB, inv->getUnwindDest(), selfPtr, cmd,
Constant::getNullValue(PtrTy));
addPredecssor(inv->getUnwindDest(), msgSend->getParent(), lookupBB);
B.SetInsertPoint(msgSend.getInstruction());
}
Value *imp = B.CreateLoad(B.CreateStructGEP(slot, 4));
msgSend.setArgument(selfIndex, B.CreateLoad(selfPtr, true));
msgSend.setCalledFunction(imp);
return CallSite(slot);
}
// InlineCallIfPossible - If it is possible to inline the specified call site,
// do so and update the CallGraph for this operation.
static bool InlineCallIfPossible(CallSite CS, CallGraph &CG,
const std::set<Function*> &SCCFunctions,
const TargetData &TD) {
Function *Callee = CS.getCalledFunction();
Function *Caller = CS.getCaller();
if (!InlineFunction(CS, &CG, &TD)) return false;
// If the inlined function had a higher stack protection level than the
// calling function, then bump up the caller's stack protection level.
if (Callee->hasFnAttr(Attribute::StackProtectReq))
Caller->addFnAttr(Attribute::StackProtectReq);
else if (Callee->hasFnAttr(Attribute::StackProtect) &&
!Caller->hasFnAttr(Attribute::StackProtectReq))
Caller->addFnAttr(Attribute::StackProtect);
// If we inlined the last possible call site to the function, delete the
// function body now.
if (Callee->use_empty() && Callee->hasLocalLinkage() &&
!SCCFunctions.count(Callee)) {
DOUT << " -> Deleting dead function: " << Callee->getName() << "\n";
CallGraphNode *CalleeNode = CG[Callee];
// Remove any call graph edges from the callee to its callees.
CalleeNode->removeAllCalledFunctions();
// Removing the node for callee from the call graph and delete it.
delete CG.removeFunctionFromModule(CalleeNode);
++NumDeleted;
}
return true;
}
unsigned Inliner::getInlineThreshold(CallSite CS) const {
int thres = InlineThreshold; // -inline-threshold or else selected by
// overall opt level
// If -inline-threshold is not given, listen to the optsize attribute when it
// would decrease the threshold.
Function *Caller = CS.getCaller();
bool OptSize = Caller && !Caller->isDeclaration() &&
Caller->getAttributes().hasAttribute(AttributeSet::FunctionIndex,
Attribute::OptimizeForSize);
if (!(InlineLimit.getNumOccurrences() > 0) && OptSize &&
OptSizeThreshold < thres)
thres = OptSizeThreshold;
// Listen to the inlinehint attribute when it would increase the threshold
// and the caller does not need to minimize its size.
Function *Callee = CS.getCalledFunction();
bool InlineHint = Callee && !Callee->isDeclaration() &&
Callee->getAttributes().hasAttribute(AttributeSet::FunctionIndex,
Attribute::InlineHint);
if (InlineHint && HintThreshold > thres
&& !Caller->getAttributes().hasAttribute(AttributeSet::FunctionIndex,
Attribute::MinSize))
thres = HintThreshold;
// Listen to the cold attribute when it would decrease the threshold.
bool ColdCallee = Callee && !Callee->isDeclaration() &&
Callee->getAttributes().hasAttribute(AttributeSet::FunctionIndex,
Attribute::Cold);
if (ColdCallee && ColdThreshold < thres)
thres = ColdThreshold;
return thres;
}
unsigned Inliner::getInlineThreshold(CallSite CS) const {
int Threshold = InlineThreshold; // -inline-threshold or else selected by
// overall opt level
// If -inline-threshold is not given, listen to the optsize attribute when it
// would decrease the threshold.
Function *Caller = CS.getCaller();
bool OptSize = Caller && !Caller->isDeclaration() &&
// FIXME: Use Function::optForSize().
Caller->hasFnAttribute(Attribute::OptimizeForSize);
if (!(InlineLimit.getNumOccurrences() > 0) && OptSize &&
OptSizeThreshold < Threshold)
Threshold = OptSizeThreshold;
Function *Callee = CS.getCalledFunction();
if (!Callee || Callee->isDeclaration())
return Threshold;
// If profile information is available, use that to adjust threshold of hot
// and cold functions.
// FIXME: The heuristic used below for determining hotness and coldness are
// based on preliminary SPEC tuning and may not be optimal. Replace this with
// a well-tuned heuristic based on *callsite* hotness and not callee hotness.
uint64_t FunctionCount = 0, MaxFunctionCount = 0;
bool HasPGOCounts = false;
if (Callee->getEntryCount() &&
Callee->getParent()->getMaximumFunctionCount()) {
HasPGOCounts = true;
FunctionCount = Callee->getEntryCount().getValue();
MaxFunctionCount =
Callee->getParent()->getMaximumFunctionCount().getValue();
}
// Listen to the inlinehint attribute or profile based hotness information
// when it would increase the threshold and the caller does not need to
// minimize its size.
bool InlineHint =
Callee->hasFnAttribute(Attribute::InlineHint) ||
(HasPGOCounts &&
FunctionCount >= (uint64_t)(0.3 * (double)MaxFunctionCount));
if (InlineHint && HintThreshold > Threshold &&
!Caller->hasFnAttribute(Attribute::MinSize))
Threshold = HintThreshold;
// Listen to the cold attribute or profile based coldness information
// when it would decrease the threshold.
bool ColdCallee =
Callee->hasFnAttribute(Attribute::Cold) ||
(HasPGOCounts &&
FunctionCount <= (uint64_t)(0.01 * (double)MaxFunctionCount));
// Command line argument for InlineLimit will override the default
// ColdThreshold. If we have -inline-threshold but no -inlinecold-threshold,
// do not use the default cold threshold even if it is smaller.
if ((InlineLimit.getNumOccurrences() == 0 ||
ColdThreshold.getNumOccurrences() > 0) && ColdCallee &&
ColdThreshold < Threshold)
Threshold = ColdThreshold;
return Threshold;
}
/// If it is possible to inline the specified call site,
/// do so and update the CallGraph for this operation.
///
/// This function also does some basic book-keeping to update the IR. The
/// InlinedArrayAllocas map keeps track of any allocas that are already
/// available from other functions inlined into the caller. If we are able to
/// inline this call site we attempt to reuse already available allocas or add
/// any new allocas to the set if not possible.
static bool InlineCallIfPossible(
CallSite CS, InlineFunctionInfo &IFI,
InlinedArrayAllocasTy &InlinedArrayAllocas, int InlineHistory,
bool InsertLifetime, function_ref<AAResults &(Function &)> &AARGetter,
ImportedFunctionsInliningStatistics &ImportedFunctionsStats) {
Function *Callee = CS.getCalledFunction();
Function *Caller = CS.getCaller();
AAResults &AAR = AARGetter(*Callee);
// Try to inline the function. Get the list of static allocas that were
// inlined.
if (!InlineFunction(CS, IFI, &AAR, InsertLifetime))
return false;
if (InlinerFunctionImportStats != InlinerFunctionImportStatsOpts::No)
ImportedFunctionsStats.recordInline(*Caller, *Callee);
AttributeFuncs::mergeAttributesForInlining(*Caller, *Callee);
if (!DisableInlinedAllocaMerging)
mergeInlinedArrayAllocas(Caller, IFI, InlinedArrayAllocas, InlineHistory);
return true;
}
bool InlineMalloc::runOnFunction(Function& F) {
Function* Malloc = F.getParent()->getFunction("gcmalloc");
if (!Malloc || Malloc->isDeclaration()) return false;
bool Changed = false;
for (Function::iterator BI = F.begin(), BE = F.end(); BI != BE; BI++) {
BasicBlock *Cur = BI;
for (BasicBlock::iterator II = Cur->begin(), IE = Cur->end(); II != IE;) {
Instruction *I = II;
II++;
CallSite Call = CallSite::get(I);
Instruction* CI = Call.getInstruction();
if (CI) {
Function* Temp = Call.getCalledFunction();
if (Temp == Malloc) {
if (dyn_cast<Constant>(Call.getArgument(0))) {
InlineFunctionInfo IFI(NULL, mvm::MvmModule::TheTargetData);
Changed |= InlineFunction(Call, IFI);
break;
}
}
}
}
}
return Changed;
}
bool StructuredModuleEditor::replaceEdge(Function *Caller,
uint64_t CallSiteIndex, Function *Destination) {
// If either the caller or the callee is not present in the CFG,
// we cannot replace the edge
if (Caller == NULL || Destination == NULL)
return false;
// If we cannot locate the specified callsite to redirect,
// we cannot replace the edge
CallSite CS;
if (!getCallSite(Caller, CallSiteIndex, CS))
return false;
Function *OldDestination = CS.getCalledFunction();
// If the old callee and the new callee do not have the same
// signature, we cannot replace the edge
if (!signaturesMatch(OldDestination, Destination))
return false;
// Sets the callsite's callee to the specified callee
CS.setCalledFunction(Destination);
CallGraphNode *DestinationNode = CG->getOrInsertFunction(Destination);
CG->getOrInsertFunction(Caller)->replaceCallEdge(CS, CS, DestinationNode);
return true;
}
// deleteValue method - This method is used to remove a pointer value from the
// AliasSetTracker entirely. It should be used when an instruction is deleted
// from the program to update the AST. If you don't use this, you would have
// dangling pointers to deleted instructions.
//
void AliasSetTracker::deleteValue(Value *PtrVal) {
// Notify the alias analysis implementation that this value is gone.
AA.deleteValue(PtrVal);
// If this is a call instruction, remove the callsite from the appropriate
// AliasSet.
CallSite CS = CallSite::get(PtrVal);
if (CS.getInstruction()) {
Function *F = CS.getCalledFunction();
if (!F || !AA.doesNotAccessMemory(F)) {
if (AliasSet *AS = findAliasSetForCallSite(CS))
AS->removeCallSite(CS);
}
}
// First, look up the PointerRec for this pointer.
hash_map<Value*, AliasSet::PointerRec>::iterator I = PointerMap.find(PtrVal);
if (I == PointerMap.end()) return; // Noop
// If we found one, remove the pointer from the alias set it is in.
AliasSet::HashNodePair &PtrValEnt = *I;
AliasSet *AS = PtrValEnt.second.getAliasSet(*this);
// Unlink from the list of values...
PtrValEnt.second.removeFromList();
// Stop using the alias set
AS->dropRef(*this);
PointerMap.erase(I);
}
unsigned Inliner::getInlineThreshold(CallSite CS) const {
int thres = InlineThreshold; // -inline-threshold or else selected by
// overall opt level
// If -inline-threshold is not given, listen to the optsize attribute when it
// would decrease the threshold.
Function *Caller = CS.getCaller();
bool OptSize = Caller && !Caller->isDeclaration() &&
Caller->hasFnAttribute(Attribute::OptimizeForSize);
if (!(InlineLimit.getNumOccurrences() > 0) && OptSize &&
OptSizeThreshold < thres)
thres = OptSizeThreshold;
// Listen to the inlinehint attribute when it would increase the threshold
// and the caller does not need to minimize its size.
Function *Callee = CS.getCalledFunction();
bool InlineHint = Callee && !Callee->isDeclaration() &&
Callee->hasFnAttribute(Attribute::InlineHint);
if (InlineHint && HintThreshold > thres &&
!Caller->hasFnAttribute(Attribute::MinSize))
thres = HintThreshold;
// Listen to the cold attribute when it would decrease the threshold.
bool ColdCallee = Callee && !Callee->isDeclaration() &&
Callee->hasFnAttribute(Attribute::Cold);
// Command line argument for InlineLimit will override the default
// ColdThreshold. If we have -inline-threshold but no -inlinecold-threshold,
// do not use the default cold threshold even if it is smaller.
if ((InlineLimit.getNumOccurrences() == 0 ||
ColdThreshold.getNumOccurrences() > 0) && ColdCallee &&
ColdThreshold < thres)
thres = ColdThreshold;
return thres;
}
/// UpdateCallGraphAfterInlining - Once we have cloned code over from a callee
/// into the caller, update the specified callgraph to reflect the changes we
/// made. Note that it's possible that not all code was copied over, so only
/// some edges of the callgraph may remain.
static void UpdateCallGraphAfterInlining(CallSite CS,
Function::iterator FirstNewBlock,
ValueToValueMapTy &VMap,
InlineFunctionInfo &IFI) {
CallGraph &CG = *IFI.CG;
const Function *Caller = CS.getInstruction()->getParent()->getParent();
const Function *Callee = CS.getCalledFunction();
CallGraphNode *CalleeNode = CG[Callee];
CallGraphNode *CallerNode = CG[Caller];
// Since we inlined some uninlined call sites in the callee into the caller,
// add edges from the caller to all of the callees of the callee.
CallGraphNode::iterator I = CalleeNode->begin(), E = CalleeNode->end();
// Consider the case where CalleeNode == CallerNode.
CallGraphNode::CalledFunctionsVector CallCache;
if (CalleeNode == CallerNode) {
CallCache.assign(I, E);
I = CallCache.begin();
E = CallCache.end();
}
for (; I != E; ++I) {
const Value *OrigCall = I->first;
ValueToValueMapTy::iterator VMI = VMap.find(OrigCall);
// Only copy the edge if the call was inlined!
if (VMI == VMap.end() || VMI->second == 0)
continue;
// If the call was inlined, but then constant folded, there is no edge to
// add. Check for this case.
Instruction *NewCall = dyn_cast<Instruction>(VMI->second);
if (NewCall == 0) continue;
// Remember that this call site got inlined for the client of
// InlineFunction.
IFI.InlinedCalls.push_back(NewCall);
// It's possible that inlining the callsite will cause it to go from an
// indirect to a direct call by resolving a function pointer. If this
// happens, set the callee of the new call site to a more precise
// destination. This can also happen if the call graph node of the caller
// was just unnecessarily imprecise.
if (I->second->getFunction() == 0)
if (Function *F = CallSite(NewCall).getCalledFunction()) {
// Indirect call site resolved to direct call.
CallerNode->addCalledFunction(CallSite(NewCall), CG[F]);
continue;
}
CallerNode->addCalledFunction(CallSite(NewCall), I->second);
}
// Update the call graph by deleting the edge from Callee to Caller. We must
// do this after the loop above in case Caller and Callee are the same.
CallerNode->removeCallEdgeFor(CS);
}
void EmitMemSet(IRBuilder<>& B, Value* Dst, Value* Val, Value* Len,
const Analysis& A) {
Dst = B.CreateBitCast(Dst, PointerType::getUnqual(B.getInt8Ty()));
CallSite CS = B.CreateMemSet(Dst, Val, Len, 1 /*Align*/, false /*isVolatile*/);
if (A.CGNode)
A.CGNode->addCalledFunction(CS, A.CG->getOrInsertFunction(CS.getCalledFunction()));
}
bool AliasSetTracker::remove(CallSite CS) {
if (Function *F = CS.getCalledFunction())
if (AA.doesNotAccessMemory(F))
return false; // doesn't alias anything
AliasSet *AS = findAliasSetForCallSite(CS);
if (!AS) return false;
remove(*AS);
return true;
}
void InstrumentFreeCalls::visitCallSite(CallSite CS) {
Function *F = CS.getCalledFunction();
if (!F || !F->hasName() || F->getName() != "free")
return;
// Insert the check right before the free call.
Instruction *I = CS.getInstruction();
IRBuilder<> Builder(I);
Builder.CreateCall(FreeCheckFunction, I->getOperand(0));
++FreeChecksInserted;
}
AliasAnalysis::ModRefBehavior
AliasAnalysis::getModRefBehavior(CallSite CS,
std::vector<PointerAccessInfo> *Info) {
if (CS.doesNotAccessMemory())
// Can't do better than this.
return DoesNotAccessMemory;
ModRefBehavior MRB = getModRefBehavior(CS.getCalledFunction(), Info);
if (MRB != DoesNotAccessMemory && CS.onlyReadsMemory())
return OnlyReadsMemory;
return MRB;
}
static bool getPossibleTargets(CallSite CS,
SmallVectorImpl<Function *> &Output) {
if (auto *Fn = CS.getCalledFunction()) {
Output.push_back(Fn);
return true;
}
// TODO: If the call is indirect, we might be able to enumerate all potential
// targets of the call and return them, rather than just failing.
return false;
}
/// \brief Get the inline cost for the always-inliner.
///
/// The always inliner *only* handles functions which are marked with the
/// attribute to force inlining. As such, it is dramatically simpler and avoids
/// using the powerful (but expensive) inline cost analysis. Instead it uses
/// a very simple and boring direct walk of the instructions looking for
/// impossible-to-inline constructs.
///
/// Note, it would be possible to go to some lengths to cache the information
/// computed here, but as we only expect to do this for relatively few and
/// small functions which have the explicit attribute to force inlining, it is
/// likely not worth it in practice.
InlineCost AlwaysInlinerLegacyPass::getInlineCost(CallSite CS) {
Function *Callee = CS.getCalledFunction();
// Only inline direct calls to functions with always-inline attributes
// that are viable for inlining. FIXME: We shouldn't even get here for
// declarations.
if (Callee && !Callee->isDeclaration() &&
CS.hasFnAttr(Attribute::AlwaysInline) && isInlineViable(*Callee))
return InlineCost::getAlways();
return InlineCost::getNever();
}
void MemoryInstrumenter::instrumentFork(const CallSite &CS) {
Instruction *Ins = CS.getInstruction();
assert(!Ins->isTerminator());
Function *Callee = CS.getCalledFunction();
StringRef CalleeName = Callee->getName();
assert(CalleeName == "fork" || CalleeName == "vfork");
BasicBlock::iterator Loc = Ins;
CallInst::Create(BeforeForkHook, "", Loc);
++Loc;
CallInst::Create(AfterForkHook, Ins, "", Loc);
}
FunctionList DSNodeEquivs::getCallees(CallSite &CS) {
const Function *CalledFunc = CS.getCalledFunction();
// If the called function is casted from one function type to another, peer
// into the cast instruction and pull out the actual function being called.
if (ConstantExpr *CExpr = dyn_cast<ConstantExpr>(CS.getCalledValue())) {
if (CExpr->getOpcode() == Instruction::BitCast &&
isa<Function>(CExpr->getOperand(0)))
CalledFunc = cast<Function>(CExpr->getOperand(0));
}
FunctionList Callees;
// Direct calls are simple.
if (CalledFunc) {
Callees.push_back(CalledFunc);
return Callees;
}
// Okay, indirect call.
// Ask the DSCallGraph what this calls...
TDDataStructures &TDDS = getAnalysis<TDDataStructures>();
const DSCallGraph &DSCG = TDDS.getCallGraph();
DSCallGraph::callee_iterator CalleeIt = DSCG.callee_begin(CS);
DSCallGraph::callee_iterator CalleeItEnd = DSCG.callee_end(CS);
for (; CalleeIt != CalleeItEnd; ++CalleeIt)
Callees.push_back(*CalleeIt);
// If the callgraph doesn't give us what we want, query the DSGraph
// ourselves.
if (Callees.empty()) {
Instruction *Inst = CS.getInstruction();
Function *Parent = Inst->getParent()->getParent();
Value *CalledValue = CS.getCalledValue();
DSNodeHandle &NH = TDDS.getDSGraph(*Parent)->getNodeForValue(CalledValue);
if (!NH.isNull()) {
DSNode *Node = NH.getNode();
Node->addFullFunctionList(Callees);
}
}
// For debugging, dump out the callsites we are unable to get callees for.
DEBUG(
if (Callees.empty()) {
errs() << "Failed to get callees for callsite:\n";
CS.getInstruction()->dump();
});
void Preparer::expandMalloc(CallSite CS) {
Function *Callee = CS.getCalledFunction();
assert(Callee);
StringRef CalleeName = Callee->getName();
if (CalleeName == "malloc" || CalleeName == "valloc") {
Value *Size = CS.getArgument(0);
Value *ExpandedSize = BinaryOperator::Create(
Instruction::Add,
Size,
ConstantInt::get(cast<IntegerType>(Size->getType()), 1),
"expanded.size",
CS.getInstruction());
CS.setArgument(0, ExpandedSize);
}
}
// Checks to see if a given CallSite is making an indirect call, including
// cases where the indirect call is made through a bitcast.
static bool isIndirectCall(CallSite &CS) {
if (CS.getCalledFunction())
return false;
// Check the value to see if it is merely a bitcast of a function. In
// this case, it will translate to a direct function call in the resulting
// assembly, so we won't treat it as an indirect call here.
const Value *V = CS.getCalledValue();
if (const ConstantExpr *CE = dyn_cast<ConstantExpr>(V)) {
return !(CE->isCast() && isa<Function>(CE->getOperand(0)));
}
// Otherwise, since we know it's a call, it must be an indirect call
return true;
}
bool AliasSetTracker::add(CallSite CS) {
if (Function *F = CS.getCalledFunction())
if (AA.doesNotAccessMemory(F))
return true; // doesn't alias anything
AliasSet *AS = findAliasSetForCallSite(CS);
if (!AS) {
AliasSets.push_back(new AliasSet());
AS = &AliasSets.back();
AS->addCallSite(CS, AA);
return true;
} else {
AS->addCallSite(CS, AA);
return false;
}
}
AliasAnalysis::ModRefResult
GlobalsModRef::getModRefInfo(CallSite CS, Value *P, unsigned Size) {
unsigned Known = ModRef;
// If we are asking for mod/ref info of a direct call with a pointer to a
// global we are tracking, return information if we have it.
if (GlobalValue *GV = dyn_cast<GlobalValue>(P->getUnderlyingObject()))
if (GV->hasLocalLinkage())
if (Function *F = CS.getCalledFunction())
if (NonAddressTakenGlobals.count(GV))
if (FunctionRecord *FR = getFunctionInfo(F))
Known = FR->getInfoForGlobal(GV);
if (Known == NoModRef)
return NoModRef; // No need to query other mod/ref analyses
return ModRefResult(Known & AliasAnalysis::getModRefInfo(CS, P, Size));
}
int InlineCostAnalyzer::getInlineBonuses(CallSite CS, Function *Callee) {
// Get information about the callee.
FunctionInfo *CalleeFI = &CachedFunctionInfo[Callee];
// If we haven't calculated this information yet, do so now.
if (CalleeFI->Metrics.NumBlocks == 0)
CalleeFI->analyzeFunction(Callee, TD);
bool isDirectCall = CS.getCalledFunction() == Callee;
Instruction *TheCall = CS.getInstruction();
int Bonus = 0;
// If there is only one call of the function, and it has internal linkage,
// make it almost guaranteed to be inlined.
//
if (Callee->hasLocalLinkage() && Callee->hasOneUse() && isDirectCall)
Bonus += InlineConstants::LastCallToStaticBonus;
// If the instruction after the call, or if the normal destination of the
// invoke is an unreachable instruction, the function is noreturn. As such,
// there is little point in inlining this.
if (InvokeInst *II = dyn_cast<InvokeInst>(TheCall)) {
if (isa<UnreachableInst>(II->getNormalDest()->begin()))
Bonus += InlineConstants::NoreturnPenalty;
} else if (isa<UnreachableInst>(++BasicBlock::iterator(TheCall)))
Bonus += InlineConstants::NoreturnPenalty;
// If this function uses the coldcc calling convention, prefer not to inline
// it.
if (Callee->getCallingConv() == CallingConv::Cold)
Bonus += InlineConstants::ColdccPenalty;
// Add to the inline quality for properties that make the call valuable to
// inline. This includes factors that indicate that the result of inlining
// the function will be optimizable. Currently this just looks at arguments
// passed into the function.
//
CallSite::arg_iterator I = CS.arg_begin();
for (Function::arg_iterator FI = Callee->arg_begin(), FE = Callee->arg_end();
FI != FE; ++I, ++FI)
// Compute any constant bonus due to inlining we want to give here.
if (isa<Constant>(I))
Bonus += CountBonusForConstant(FI, cast<Constant>(I));
return Bonus;
}
// getModRefInfo - Check to see if the specified callsite can clobber the
// specified memory object.
//
AliasAnalysis::ModRefResult
LibCallAliasAnalysis::getModRefInfo(CallSite CS, Value *P, unsigned Size) {
ModRefResult MRInfo = ModRef;
// If this is a direct call to a function that LCI knows about, get the
// information about the runtime function.
if (LCI) {
if (Function *F = CS.getCalledFunction()) {
if (const LibCallFunctionInfo *FI = LCI->getFunctionInfo(F)) {
MRInfo = ModRefResult(MRInfo & AnalyzeLibCallDetails(FI, CS, P, Size));
if (MRInfo == NoModRef) return NoModRef;
}
}
}
// The AliasAnalysis base class has some smarts, lets use them.
return (ModRefResult)(MRInfo | AliasAnalysis::getModRefInfo(CS, P, Size));
}
void AliasSet::addCallSite(CallSite CS, AliasAnalysis &AA) {
CallSites.push_back(CS);
if (Function *F = CS.getCalledFunction()) {
AliasAnalysis::ModRefBehavior Behavior = AA.getModRefBehavior(F, CS);
if (Behavior == AliasAnalysis::DoesNotAccessMemory)
return;
else if (Behavior == AliasAnalysis::OnlyReadsMemory) {
AliasTy = MayAlias;
AccessTy |= Refs;
return;
}
}
// FIXME: This should use mod/ref information to make this not suck so bad
AliasTy = MayAlias;
AccessTy = ModRef;
}
unsigned Inliner::getInlineThreshold(CallSite CS) const {
int thres = InlineThreshold;
// Listen to optsize when -inline-limit is not given.
Function *Caller = CS.getCaller();
if (Caller && !Caller->isDeclaration() &&
Caller->hasFnAttr(Attribute::OptimizeForSize) &&
InlineLimit.getNumOccurrences() == 0)
thres = OptSizeThreshold;
// Listen to inlinehint when it would increase the threshold.
Function *Callee = CS.getCalledFunction();
if (HintThreshold > thres && Callee && !Callee->isDeclaration() &&
Callee->hasFnAttr(Attribute::InlineHint))
thres = HintThreshold;
return thres;
}
// addToCallGraph - Add a function to the call graph, and link the node to all
// of the functions that it calls.
//
void addToCallGraph(Function *F) {
CallGraphNode *Node = getOrInsertFunction(F);
// If this function has external linkage, anything could call it.
if (!F->hasLocalLinkage()) {
ExternalCallingNode->addCalledFunction(CallSite(), Node);
// Found the entry point?
if (F->getName() == "main") {
if (Root) // Found multiple external mains? Don't pick one.
Root = ExternalCallingNode;
else
Root = Node; // Found a main, keep track of it!
}
}
// Loop over all of the users of the function, looking for non-call uses.
for (Value::use_iterator I = F->use_begin(), E = F->use_end(); I != E; ++I)
if ((!isa<CallInst>(I) && !isa<InvokeInst>(I))
|| !CallSite(cast<Instruction>(I)).isCallee(I)) {
// Not a call, or being used as a parameter rather than as the callee.
ExternalCallingNode->addCalledFunction(CallSite(), Node);
break;
}
// If this function is not defined in this translation unit, it could call
// anything.
if (F->isDeclaration() && !F->isIntrinsic())
Node->addCalledFunction(CallSite(), CallsExternalNode);
// Look for calls by this function.
for (Function::iterator BB = F->begin(), BBE = F->end(); BB != BBE; ++BB)
for (BasicBlock::iterator II = BB->begin(), IE = BB->end();
II != IE; ++II) {
CallSite CS = CallSite::get(II);
if (CS.getInstruction() && !isa<DbgInfoIntrinsic>(II)) {
const Function *Callee = CS.getCalledFunction();
if (Callee)
Node->addCalledFunction(CS, getOrInsertFunction(Callee));
else
Node->addCalledFunction(CS, CallsExternalNode);
}
}
}
bool AliasSet::aliasesCallSite(CallSite CS, AliasAnalysis &AA) const {
if (Function *F = CS.getCalledFunction())
if (AA.doesNotAccessMemory(F))
return false;
if (AA.hasNoModRefInfoForCalls())
return true;
for (unsigned i = 0, e = CallSites.size(); i != e; ++i)
if (AA.getModRefInfo(CallSites[i], CS) != AliasAnalysis::NoModRef ||
AA.getModRefInfo(CS, CallSites[i]) != AliasAnalysis::NoModRef)
return true;
for (iterator I = begin(), E = end(); I != E; ++I)
if (AA.getModRefInfo(CS, I.getPointer(), I.getSize()) !=
AliasAnalysis::NoModRef)
return true;
return false;
}
/// \brief Get the inline cost for the always-inliner.
///
/// The always inliner *only* handles functions which are marked with the
/// attribute to force inlining. As such, it is dramatically simpler and avoids
/// using the powerful (but expensive) inline cost analysis. Instead it uses
/// a very simple and boring direct walk of the instructions looking for
/// impossible-to-inline constructs.
///
/// Note, it would be possible to go to some lengths to cache the information
/// computed here, but as we only expect to do this for relatively few and
/// small functions which have the explicit attribute to force inlining, it is
/// likely not worth it in practice.
InlineCost AlwaysInliner::getInlineCost(CallSite CS) {
Function *Callee = CS.getCalledFunction();
// We assume indirect calls aren't calling an always-inline function.
if (!Callee) return InlineCost::getNever();
// We can't inline calls to external functions.
// FIXME: We shouldn't even get here.
if (Callee->isDeclaration()) return InlineCost::getNever();
// Return never for anything not marked as always inline.
if (!Callee->getFnAttributes().hasAttribute(Attributes::AlwaysInline))
return InlineCost::getNever();
// Do some minimal analysis to preclude non-viable functions.
if (!isInlineViable(*Callee))
return InlineCost::getNever();
// Otherwise, force inlining.
return InlineCost::getAlways();
}
