/// Checks whether any of the arguments to the apply are closures and diagnoses
/// if any of the @inout_aliasable captures passed to those closures have
/// in-progress accesses that would conflict with any access the summary
/// says the closure would perform.
//
/// TODO: We currently fail to statically diagnose non-escaping closures pased
/// via @block_storage convention. To enforce this case, we should statically
/// recognize when the apply takes a block argument that has been initialized to
/// a non-escaping closure.
static void checkForViolationsInNoEscapeClosures(
const StorageMap &Accesses, FullApplySite FAS, AccessSummaryAnalysis *ASA,
llvm::SmallVectorImpl<ConflictingAccess> &ConflictingAccesses) {
SILFunction *Callee = FAS.getCalleeFunction();
if (Callee && !Callee->empty()) {
// Check for violation with directly called closure
checkForViolationWithCall(Accesses, Callee, 0, FAS.getArguments(), ASA,
ConflictingAccesses);
}
// Check for violation with closures passed as arguments
for (SILValue Argument : FAS.getArguments()) {
auto *PAI = lookThroughForPartialApply(Argument);
if (!PAI)
continue;
SILFunction *Closure = PAI->getCalleeFunction();
if (!Closure || Closure->empty())
continue;
// Check the closure's captures, which are a suffix of the closure's
// parameters.
unsigned StartIndex =
Closure->getArguments().size() - PAI->getNumCallArguments();
checkForViolationWithCall(Accesses, Closure, StartIndex,
PAI->getArguments(), ASA, ConflictingAccesses);
}
}
// Analyzing the body of this class destructor is valid because the object is
// dead. This means that the object is never passed to objc_setAssociatedObject,
// so its destructor cannot be extended at runtime.
static SILFunction *getDestructor(AllocRefInst *ARI) {
// We only support classes.
ClassDecl *ClsDecl = ARI->getType().getClassOrBoundGenericClass();
if (!ClsDecl)
return nullptr;
// Look up the destructor of ClsDecl.
DestructorDecl *Destructor = ClsDecl->getDestructor();
assert(Destructor && "getDestructor() should never return a nullptr.");
// Find the destructor name via SILDeclRef.
// FIXME: When destructors get moved into vtables, update this to use the
// vtable for the class.
SILDeclRef Ref(Destructor);
SILFunction *Fn = ARI->getModule().lookUpFunction(Ref);
if (!Fn || Fn->empty()) {
DEBUG(llvm::dbgs() << " Could not find destructor.\n");
return nullptr;
}
DEBUG(llvm::dbgs() << " Found destructor!\n");
// If the destructor has an objc_method calling convention, we cannot
// analyze it since it could be swapped out from under us at runtime.
if (Fn->getRepresentation() == SILFunctionTypeRepresentation::ObjCMethod) {
DEBUG(llvm::dbgs() << " Found objective-c destructor. Can't "
"analyze!\n");
return nullptr;
}
return Fn;
}
void AccessSummaryAnalysis::processPartialApply(FunctionInfo *callerInfo,
unsigned callerArgumentIndex,
PartialApplyInst *apply,
Operand *applyArgumentOperand,
FunctionOrder &order) {
SILFunction *calleeFunction = apply->getCalleeFunction();
assert(calleeFunction && !calleeFunction->empty() &&
"Missing definition of noescape closure?");
// Make sure the partial_apply is not calling the result of another
// partial_apply.
assert(isa<FunctionRefInst>(apply->getCallee()) &&
"Noescape partial apply of non-functionref?");
assert(llvm::all_of(apply->getUses(),
hasExpectedUsesOfNoEscapePartialApply) &&
"noescape partial_apply has unexpected use!");
// The argument index in the called function.
ApplySite site(apply);
unsigned calleeArgumentIndex = site.getCalleeArgIndex(*applyArgumentOperand);
processCall(callerInfo, callerArgumentIndex, calleeFunction,
calleeArgumentIndex, order);
}
/// Could this operand to an apply escape that function by being
/// stored or returned?
static bool applyArgumentEscapes(FullApplySite Apply, Operand *O) {
SILFunction *F = Apply.getReferencedFunction();
// If we cannot examine the function body, assume the worst.
if (!F || F->empty())
return true;
// Check the uses of the operand, but do not recurse down into other
// apply instructions.
auto calleeArg = F->getArgument(Apply.getCalleeArgIndex(*O));
return partialApplyEscapes(calleeArg, /* examineApply = */ false);
}
/// checkPartialApplyBody - Check the body of a partial apply to see
/// if the box pointer argument passed to it has uses that would
/// disqualify it from being promoted to a stack location. Return
/// true if this partial apply will not block our promoting the box.
static bool checkPartialApplyBody(Operand *O) {
SILFunction *F = ApplySite(O->getUser()).getReferencedFunction();
// If we cannot examine the function body, assume the worst.
if (!F || F->empty())
return false;
// We don't actually use these because we're not recursively
// rewriting the partial applies we find.
llvm::SmallVector<Operand *, 1> PromotedOperands;
auto calleeArg = F->getArgument(ApplySite(O->getUser()).getCalleeArgIndex(*O));
return !findUnexpectedBoxUse(calleeArg, /* examinePartialApply = */ false,
/* inAppliedFunction = */ true,
PromotedOperands);
}
void AccessEnforcementDom::run() {
SILFunction *func = getFunction();
if (func->empty())
return;
PostOrderFunctionInfo *PO = getAnalysis<PostOrderAnalysis>()->get(func);
auto DAA = DominatedAccessAnalysis(PO).analyze();
DominanceAnalysis *domAnalysis = getAnalysis<DominanceAnalysis>();
DominanceInfo *domInfo = domAnalysis->get(func);
SILLoopAnalysis *loopAnalysis = PM->getAnalysis<SILLoopAnalysis>();
SILLoopInfo *loopInfo = loopAnalysis->get(func);
DominatedAccessRemoval eliminationPass(*func, domInfo, loopInfo, DAA);
if (eliminationPass.optimize())
invalidateAnalysis(SILAnalysis::InvalidationKind::Instructions);
}
void AccessSummaryAnalysis::processFullApply(FunctionInfo *callerInfo,
unsigned callerArgumentIndex,
FullApplySite apply,
Operand *argumentOperand,
FunctionOrder &order) {
unsigned operandNumber = argumentOperand->getOperandNumber();
assert(operandNumber > 0 && "Summarizing apply for non-argument?");
unsigned calleeArgumentIndex = operandNumber - 1;
SILFunction *callee = apply.getCalleeFunction();
// We can't apply a summary for function whose body we can't see.
// Since user-provided closures are always in the same module as their callee
// This likely indicates a missing begin_access before an open-coded
// call.
if (!callee || callee->empty())
return;
processCall(callerInfo, callerArgumentIndex, callee, calleeArgumentIndex,
order);
}
/// For each argument in the range of the callee arguments being applied at the
/// given apply site, use the summary analysis to determine whether the
/// arguments will be accessed in a way that conflicts with any currently in
/// progress accesses. If so, diagnose.
static void checkCaptureAccess(ApplySite Apply, AccessState &State) {
SILFunction *Callee = Apply.getCalleeFunction();
if (!Callee || Callee->empty())
return;
const AccessSummaryAnalysis::FunctionSummary &FS =
State.ASA->getOrCreateSummary(Callee);
for (unsigned ArgumentIndex : range(Apply.getNumArguments())) {
unsigned CalleeIndex =
Apply.getCalleeArgIndexOfFirstAppliedArg() + ArgumentIndex;
const AccessSummaryAnalysis::ArgumentSummary &AS =
FS.getAccessForArgument(CalleeIndex);
const auto &SubAccesses = AS.getSubAccesses();
// Is the capture accessed in the callee?
if (SubAccesses.empty())
continue;
SILValue Argument = Apply.getArgument(ArgumentIndex);
assert(Argument->getType().isAddress());
// A valid AccessedStorage should alway sbe found because Unsafe accesses
// are not tracked by AccessSummaryAnalysis.
const AccessedStorage &Storage = findValidAccessedStorage(Argument);
auto AccessIt = State.Accesses->find(Storage);
// Are there any accesses in progress at the time of the call?
if (AccessIt == State.Accesses->end())
continue;
const AccessInfo &Info = AccessIt->getSecond();
if (auto Conflict = findConflictingArgumentAccess(AS, Storage, Info))
State.ConflictingAccesses.push_back(*Conflict);
}
}
/// Returns the callee SILFunction called at a call site, in the case
/// that the call is transparent (as in, both that the call is marked
/// with the transparent flag and that callee function is actually transparently
/// determinable from the SIL) or nullptr otherwise. This assumes that the SIL
/// is already in SSA form.
///
/// In the case that a non-null value is returned, FullArgs contains effective
/// argument operands for the callee function.
static SILFunction *getCalleeFunction(
SILFunction *F, FullApplySite AI, bool &IsThick,
SmallVectorImpl<std::pair<SILValue, ParameterConvention>> &CaptureArgs,
SmallVectorImpl<SILValue> &FullArgs, PartialApplyInst *&PartialApply) {
IsThick = false;
PartialApply = nullptr;
CaptureArgs.clear();
FullArgs.clear();
for (const auto &Arg : AI.getArguments())
FullArgs.push_back(Arg);
SILValue CalleeValue = AI.getCallee();
if (auto *LI = dyn_cast<LoadInst>(CalleeValue)) {
// Conservatively only see through alloc_box; we assume this pass is run
// immediately after SILGen
auto *PBI = dyn_cast<ProjectBoxInst>(LI->getOperand());
if (!PBI)
return nullptr;
auto *ABI = dyn_cast<AllocBoxInst>(PBI->getOperand());
if (!ABI)
return nullptr;
// Ensure there are no other uses of alloc_box than the project_box and
// retains, releases.
for (Operand *ABIUse : ABI->getUses())
if (ABIUse->getUser() != PBI &&
!isa<StrongRetainInst>(ABIUse->getUser()) &&
!isa<StrongReleaseInst>(ABIUse->getUser()))
return nullptr;
// Scan forward from the alloc box to find the first store, which
// (conservatively) must be in the same basic block as the alloc box
StoreInst *SI = nullptr;
for (auto I = SILBasicBlock::iterator(ABI), E = I->getParent()->end();
I != E; ++I) {
// If we find the load instruction first, then the load is loading from
// a non-initialized alloc; this shouldn't really happen but I'm not
// making any assumptions
if (&*I == LI)
return nullptr;
if ((SI = dyn_cast<StoreInst>(I)) && SI->getDest() == PBI) {
// We found a store that we know dominates the load; now ensure there
// are no other uses of the project_box except loads.
for (Operand *PBIUse : PBI->getUses())
if (PBIUse->getUser() != SI && !isa<LoadInst>(PBIUse->getUser()))
return nullptr;
// We can conservatively see through the store
break;
}
}
if (!SI)
return nullptr;
CalleeValue = SI->getSrc();
}
// PartialApply/ThinToThick -> ConvertFunction patterns are generated
// by @noescape closures.
//
// FIXME: We don't currently handle mismatched return types, however, this
// would be a good optimization to handle and would be as simple as inserting
// a cast.
auto skipFuncConvert = [](SILValue CalleeValue) {
// We can also allow a thin @escape to noescape conversion as such:
// %1 = function_ref @thin_closure_impl : $@convention(thin) () -> ()
// %2 = convert_function %1 :
// $@convention(thin) () -> () to $@convention(thin) @noescape () -> ()
// %3 = thin_to_thick_function %2 :
// $@convention(thin) @noescape () -> () to
// $@noescape @callee_guaranteed () -> ()
// %4 = apply %3() : $@noescape @callee_guaranteed () -> ()
if (auto *ThinToNoescapeCast = dyn_cast<ConvertFunctionInst>(CalleeValue)) {
auto FromCalleeTy =
ThinToNoescapeCast->getOperand()->getType().castTo<SILFunctionType>();
if (FromCalleeTy->getExtInfo().hasContext())
return CalleeValue;
auto ToCalleeTy = ThinToNoescapeCast->getType().castTo<SILFunctionType>();
auto EscapingCalleeTy = ToCalleeTy->getWithExtInfo(
ToCalleeTy->getExtInfo().withNoEscape(false));
if (FromCalleeTy != EscapingCalleeTy)
return CalleeValue;
return ThinToNoescapeCast->getOperand();
}
auto *CFI = dyn_cast<ConvertEscapeToNoEscapeInst>(CalleeValue);
if (!CFI)
return CalleeValue;
// TODO: Handle argument conversion. All the code in this file needs to be
// cleaned up and generalized. The argument conversion handling in
// optimizeApplyOfConvertFunctionInst should apply to any combine
// involving an apply, not just a specific pattern.
//
// For now, just handle conversion that doesn't affect argument types,
// return types, or throws. We could trivially handle any other
// representation change, but the only one that doesn't affect the ABI and
// matters here is @noescape, so just check for that.
auto FromCalleeTy = CFI->getOperand()->getType().castTo<SILFunctionType>();
auto ToCalleeTy = CFI->getType().castTo<SILFunctionType>();
auto EscapingCalleeTy =
ToCalleeTy->getWithExtInfo(ToCalleeTy->getExtInfo().withNoEscape(false));
if (FromCalleeTy != EscapingCalleeTy)
return CalleeValue;
return CFI->getOperand();
};
// Look through a escape to @noescape conversion.
CalleeValue = skipFuncConvert(CalleeValue);
// We are allowed to see through exactly one "partial apply" instruction or
// one "thin to thick function" instructions, since those are the patterns
// generated when using auto closures.
if (auto *PAI = dyn_cast<PartialApplyInst>(CalleeValue)) {
// Collect the applied arguments and their convention.
collectPartiallyAppliedArguments(PAI, CaptureArgs, FullArgs);
CalleeValue = PAI->getCallee();
IsThick = true;
PartialApply = PAI;
} else if (auto *TTTFI = dyn_cast<ThinToThickFunctionInst>(CalleeValue)) {
CalleeValue = TTTFI->getOperand();
IsThick = true;
}
CalleeValue = skipFuncConvert(CalleeValue);
auto *FRI = dyn_cast<FunctionRefInst>(CalleeValue);
if (!FRI)
return nullptr;
SILFunction *CalleeFunction = FRI->getReferencedFunction();
switch (CalleeFunction->getRepresentation()) {
case SILFunctionTypeRepresentation::Thick:
case SILFunctionTypeRepresentation::Thin:
case SILFunctionTypeRepresentation::Method:
case SILFunctionTypeRepresentation::Closure:
case SILFunctionTypeRepresentation::WitnessMethod:
break;
case SILFunctionTypeRepresentation::CFunctionPointer:
case SILFunctionTypeRepresentation::ObjCMethod:
case SILFunctionTypeRepresentation::Block:
return nullptr;
}
// If the CalleeFunction is a not-transparent definition, we can not process
// it.
if (CalleeFunction->isTransparent() == IsNotTransparent)
return nullptr;
// If CalleeFunction is a declaration, see if we can load it.
if (CalleeFunction->empty())
AI.getModule().loadFunction(CalleeFunction);
// If we fail to load it, bail.
if (CalleeFunction->empty())
return nullptr;
if (F->isSerialized() &&
!CalleeFunction->hasValidLinkageForFragileInline()) {
if (!CalleeFunction->hasValidLinkageForFragileRef()) {
llvm::errs() << "caller: " << F->getName() << "\n";
llvm::errs() << "callee: " << CalleeFunction->getName() << "\n";
llvm_unreachable("Should never be inlining a resilient function into "
"a fragile function");
}
return nullptr;
}
return CalleeFunction;
}
/// \brief Returns the callee SILFunction called at a call site, in the case
/// that the call is transparent (as in, both that the call is marked
/// with the transparent flag and that callee function is actually transparently
/// determinable from the SIL) or nullptr otherwise. This assumes that the SIL
/// is already in SSA form.
///
/// In the case that a non-null value is returned, FullArgs contains effective
/// argument operands for the callee function.
static SILFunction *
getCalleeFunction(FullApplySite AI, bool &IsThick,
SmallVectorImpl<SILValue>& CaptureArgs,
SmallVectorImpl<SILValue>& FullArgs,
PartialApplyInst *&PartialApply,
SILModule::LinkingMode Mode) {
IsThick = false;
PartialApply = nullptr;
CaptureArgs.clear();
FullArgs.clear();
for (const auto &Arg : AI.getArguments())
FullArgs.push_back(Arg);
SILValue CalleeValue = AI.getCallee();
if (LoadInst *LI = dyn_cast<LoadInst>(CalleeValue)) {
assert(CalleeValue.getResultNumber() == 0);
// Conservatively only see through alloc_box; we assume this pass is run
// immediately after SILGen
SILInstruction *ABI = dyn_cast<AllocBoxInst>(LI->getOperand());
if (!ABI)
return nullptr;
assert(LI->getOperand().getResultNumber() == 1);
// Scan forward from the alloc box to find the first store, which
// (conservatively) must be in the same basic block as the alloc box
StoreInst *SI = nullptr;
for (auto I = SILBasicBlock::iterator(ABI), E = I->getParent()->end();
I != E; ++I) {
// If we find the load instruction first, then the load is loading from
// a non-initialized alloc; this shouldn't really happen but I'm not
// making any assumptions
if (static_cast<SILInstruction*>(I) == LI)
return nullptr;
if ((SI = dyn_cast<StoreInst>(I)) && SI->getDest().getDef() == ABI) {
// We found a store that we know dominates the load; now ensure there
// are no other uses of the alloc other than loads, retains, releases
// and dealloc stacks
for (auto UI = ABI->use_begin(), UE = ABI->use_end(); UI != UE;
++UI)
if (UI.getUser() != SI && !isa<LoadInst>(UI.getUser()) &&
!isa<StrongRetainInst>(UI.getUser()) &&
!isa<StrongReleaseInst>(UI.getUser()))
return nullptr;
// We can conservatively see through the store
break;
}
}
if (!SI)
return nullptr;
CalleeValue = SI->getSrc();
}
// We are allowed to see through exactly one "partial apply" instruction or
// one "thin to thick function" instructions, since those are the patterns
// generated when using auto closures.
if (PartialApplyInst *PAI =
dyn_cast<PartialApplyInst>(CalleeValue)) {
assert(CalleeValue.getResultNumber() == 0);
for (const auto &Arg : PAI->getArguments()) {
CaptureArgs.push_back(Arg);
FullArgs.push_back(Arg);
}
CalleeValue = PAI->getCallee();
IsThick = true;
PartialApply = PAI;
} else if (ThinToThickFunctionInst *TTTFI =
dyn_cast<ThinToThickFunctionInst>(CalleeValue)) {
assert(CalleeValue.getResultNumber() == 0);
CalleeValue = TTTFI->getOperand();
IsThick = true;
}
FunctionRefInst *FRI = dyn_cast<FunctionRefInst>(CalleeValue);
if (!FRI)
return nullptr;
SILFunction *CalleeFunction = FRI->getReferencedFunction();
switch (CalleeFunction->getRepresentation()) {
case SILFunctionTypeRepresentation::Thick:
case SILFunctionTypeRepresentation::Thin:
case SILFunctionTypeRepresentation::Method:
case SILFunctionTypeRepresentation::WitnessMethod:
break;
case SILFunctionTypeRepresentation::CFunctionPointer:
case SILFunctionTypeRepresentation::ObjCMethod:
case SILFunctionTypeRepresentation::Block:
return nullptr;
}
// If CalleeFunction is a declaration, see if we can load it. If we fail to
// load it, bail.
if (CalleeFunction->empty()
&& !AI.getModule().linkFunction(CalleeFunction, Mode))
return nullptr;
return CalleeFunction;
}
static bool removeUnreachableBlocks(SILFunction &F, SILModule &M,
UnreachableUserCodeReportingState *State) {
if (F.empty())
return false;
SILBasicBlockSet Reachable;
SmallVector<SILBasicBlock*, 128> Worklist;
Worklist.push_back(&F.front());
Reachable.insert(&F.front());
// Collect all reachable blocks by walking the successors.
do {
SILBasicBlock *BB = Worklist.pop_back_val();
for (auto SI = BB->succ_begin(), SE = BB->succ_end(); SI != SE; ++SI) {
if (Reachable.insert(*SI).second)
Worklist.push_back(*SI);
}
} while (!Worklist.empty());
assert(Reachable.size() <= F.size());
// If everything is reachable, we are done.
if (Reachable.size() == F.size())
return false;
// Diagnose user written unreachable code.
if (State) {
for (auto BI = State->PossiblyUnreachableBlocks.begin(),
BE = State->PossiblyUnreachableBlocks.end(); BI != BE; ++BI) {
const SILBasicBlock *BB = *BI;
if (!Reachable.count(BB)) {
llvm::SmallPtrSet<const SILBasicBlock *, 1> visited;
diagnoseUnreachableBlock(**BI, M, Reachable, State, BB, visited);
}
}
}
// Remove references from the dead blocks.
for (auto I = F.begin(), E = F.end(); I != E; ++I) {
SILBasicBlock *BB = &*I;
if (Reachable.count(BB))
continue;
// Drop references to other blocks.
recursivelyDeleteTriviallyDeadInstructions(BB->getTerminator(), true);
NumInstructionsRemoved++;
}
// Delete dead instructions and everything that could become dead after
// their deletion.
llvm::SmallVector<SILInstruction*, 32> ToBeDeleted;
for (auto BI = F.begin(), BE = F.end(); BI != BE; ++BI)
if (!Reachable.count(&*BI))
for (auto I = BI->begin(), E = BI->end(); I != E; ++I)
ToBeDeleted.push_back(&*I);
recursivelyDeleteTriviallyDeadInstructions(ToBeDeleted, true);
NumInstructionsRemoved += ToBeDeleted.size();
// Delete the dead blocks.
for (auto I = F.begin(), E = F.end(); I != E;)
if (!Reachable.count(&*I)) {
I = F.getBlocks().erase(I);
NumBlocksRemoved++;
} else
++I;
return true;
}
static void checkStaticExclusivity(SILFunction &Fn, PostOrderFunctionInfo *PO,
AccessSummaryAnalysis *ASA) {
// The implementation relies on the following SIL invariants:
// - All incoming edges to a block must have the same in-progress
// accesses. This enables the analysis to not perform a data flow merge
// on incoming edges.
// - Further, for a given address each of the in-progress
// accesses must have begun in the same order on all edges. This ensures
// consistent diagnostics across changes to the exploration of the CFG.
// - On return from a function there are no in-progress accesses. This
// enables a sanity check for lean analysis state at function exit.
// - Each end_access instruction corresponds to exactly one begin access
// instruction. (This is encoded in the EndAccessInst itself)
// - begin_access arguments cannot be basic block arguments.
// This enables the analysis to look back to find the *single* storage
// storage location accessed.
if (Fn.empty())
return;
AccessState State(ASA);
// For each basic block, track the stack of current accesses on
// exit from that block.
llvm::SmallDenseMap<SILBasicBlock *, Optional<StorageMap>, 32>
BlockOutAccesses;
BlockOutAccesses[Fn.getEntryBlock()] = StorageMap();
for (auto *BB : PO->getReversePostOrder()) {
Optional<StorageMap> &BBState = BlockOutAccesses[BB];
// Because we use a reverse post-order traversal, unless this is the entry
// at least one of its predecessors must have been reached. Use the out
// state for that predecessor as our in state. The SIL verifier guarantees
// that all incoming edges must have the same current accesses.
for (auto *Pred : BB->getPredecessorBlocks()) {
auto it = BlockOutAccesses.find(Pred);
if (it == BlockOutAccesses.end())
continue;
const Optional<StorageMap> &PredAccesses = it->getSecond();
if (PredAccesses) {
BBState = PredAccesses;
break;
}
}
// The in-progress accesses for the current program point, represented
// as map from storage locations to the accesses in progress for the
// location.
State.Accesses = BBState.getPointer();
for (auto &I : *BB)
checkForViolationsAtInstruction(I, State);
}
// Now that we've collected violations and suppressed calls, emit
// diagnostics.
for (auto &Violation : State.ConflictingAccesses) {
diagnoseExclusivityViolation(Violation, State.CallsToSwap,
Fn.getASTContext());
}
}
// Returns the callee of an apply_inst if it is basically inlinable.
SILFunction *swift::getEligibleFunction(FullApplySite AI,
InlineSelection WhatToInline) {
SILFunction *Callee = AI.getReferencedFunction();
if (!Callee) {
return nullptr;
}
// Not all apply sites can be inlined, even if they're direct.
if (!SILInliner::canInline(AI))
return nullptr;
ModuleDecl *SwiftModule = Callee->getModule().getSwiftModule();
bool IsInStdlib = (SwiftModule->isStdlibModule() ||
SwiftModule->isOnoneSupportModule());
// Don't inline functions that are marked with the @_semantics or @_effects
// attribute if the inliner is asked not to inline them.
if (Callee->hasSemanticsAttrs() || Callee->hasEffectsKind()) {
if (WhatToInline == InlineSelection::NoSemanticsAndGlobalInit) {
if (shouldSkipApplyDuringEarlyInlining(AI))
return nullptr;
if (Callee->hasSemanticsAttr("inline_late"))
return nullptr;
}
// The "availability" semantics attribute is treated like global-init.
if (Callee->hasSemanticsAttrs() &&
WhatToInline != InlineSelection::Everything &&
(Callee->hasSemanticsAttrThatStartsWith("availability") ||
(Callee->hasSemanticsAttrThatStartsWith("inline_late")))) {
return nullptr;
}
if (Callee->hasSemanticsAttrs() &&
WhatToInline == InlineSelection::Everything) {
if (Callee->hasSemanticsAttrThatStartsWith("inline_late") && IsInStdlib) {
return nullptr;
}
}
} else if (Callee->isGlobalInit()) {
if (WhatToInline != InlineSelection::Everything) {
return nullptr;
}
}
// We can't inline external declarations.
if (Callee->empty() || Callee->isExternalDeclaration()) {
return nullptr;
}
// Explicitly disabled inlining.
if (Callee->getInlineStrategy() == NoInline) {
return nullptr;
}
if (!Callee->shouldOptimize()) {
return nullptr;
}
SILFunction *Caller = AI.getFunction();
// We don't support inlining a function that binds dynamic self because we
// have no mechanism to preserve the original function's local self metadata.
if (mayBindDynamicSelf(Callee)) {
// Check if passed Self is the same as the Self of the caller.
// In this case, it is safe to inline because both functions
// use the same Self.
if (AI.hasSelfArgument() && Caller->hasSelfParam()) {
auto CalleeSelf = stripCasts(AI.getSelfArgument());
auto CallerSelf = Caller->getSelfArgument();
if (CalleeSelf != SILValue(CallerSelf))
return nullptr;
} else
return nullptr;
}
// Detect self-recursive calls.
if (Caller == Callee) {
return nullptr;
}
// A non-fragile function may not be inlined into a fragile function.
if (Caller->isSerialized() &&
!Callee->hasValidLinkageForFragileInline()) {
if (!Callee->hasValidLinkageForFragileRef()) {
llvm::errs() << "caller: " << Caller->getName() << "\n";
llvm::errs() << "callee: " << Callee->getName() << "\n";
llvm_unreachable("Should never be inlining a resilient function into "
"a fragile function");
}
return nullptr;
}
// Inlining self-recursive functions into other functions can result
// in excessive code duplication since we run the inliner multiple
// times in our pipeline
if (calleeIsSelfRecursive(Callee)) {
return nullptr;
}
if (!EnableSILInliningOfGenerics && AI.hasSubstitutions()) {
// Inlining of generics is not allowed unless it is an @inline(__always)
// or transparent function.
if (Callee->getInlineStrategy() != AlwaysInline && !Callee->isTransparent())
return nullptr;
}
// We cannot inline function with layout constraints on its generic types
// if the corresponding substitution type does not have the same constraints.
// The reason for this restriction is that we'd need to be able to express
// in SIL something like casting a value of generic type T into a value of
// generic type T: _LayoutConstraint, which is impossible currently.
if (EnableSILInliningOfGenerics && AI.hasSubstitutions()) {
if (!isCallerAndCalleeLayoutConstraintsCompatible(AI))
return nullptr;
}
// IRGen cannot handle partial_applies containing opened_existentials
// in its substitutions list.
if (calleeHasPartialApplyWithOpenedExistentials(AI)) {
return nullptr;
}
return Callee;
}
// Returns the callee of an apply_inst if it is basically inlineable.
SILFunction *SILPerformanceInliner::getEligibleFunction(FullApplySite AI) {
SILFunction *Callee = AI.getCalleeFunction();
if (!Callee) {
DEBUG(llvm::dbgs() << " FAIL: Cannot find inlineable callee.\n");
return nullptr;
}
// Don't inline functions that are marked with the @_semantics or @effects
// attribute if the inliner is asked not to inline them.
if (Callee->hasSemanticsAttrs() || Callee->hasEffectsKind()) {
if (WhatToInline == InlineSelection::NoSemanticsAndGlobalInit) {
DEBUG(llvm::dbgs() << " FAIL: Function " << Callee->getName()
<< " has special semantics or effects attribute.\n");
return nullptr;
}
// The "availability" semantics attribute is treated like global-init.
if (Callee->hasSemanticsAttrs() &&
WhatToInline != InlineSelection::Everything &&
Callee->hasSemanticsAttrThatStartsWith("availability")) {
return nullptr;
}
} else if (Callee->isGlobalInit()) {
if (WhatToInline != InlineSelection::Everything) {
DEBUG(llvm::dbgs() << " FAIL: Function " << Callee->getName()
<< " has the global-init attribute.\n");
return nullptr;
}
}
// We can't inline external declarations.
if (Callee->empty() || Callee->isExternalDeclaration()) {
DEBUG(llvm::dbgs() << " FAIL: Cannot inline external " <<
Callee->getName() << ".\n");
return nullptr;
}
// Explicitly disabled inlining.
if (Callee->getInlineStrategy() == NoInline) {
DEBUG(llvm::dbgs() << " FAIL: noinline attribute on " <<
Callee->getName() << ".\n");
return nullptr;
}
if (!Callee->shouldOptimize()) {
DEBUG(llvm::dbgs() << " FAIL: optimizations disabled on " <<
Callee->getName() << ".\n");
return nullptr;
}
// We don't support this yet.
if (AI.hasSubstitutions()) {
DEBUG(llvm::dbgs() << " FAIL: Generic substitutions on " <<
Callee->getName() << ".\n");
return nullptr;
}
// We don't support inlining a function that binds dynamic self because we
// have no mechanism to preserve the original function's local self metadata.
if (computeMayBindDynamicSelf(Callee)) {
DEBUG(llvm::dbgs() << " FAIL: Binding dynamic Self in " <<
Callee->getName() << ".\n");
return nullptr;
}
SILFunction *Caller = AI.getFunction();
// Detect inlining cycles.
if (hasInliningCycle(Caller, Callee)) {
DEBUG(llvm::dbgs() << " FAIL: Detected a recursion inlining " <<
Callee->getName() << ".\n");
return nullptr;
}
// A non-fragile function may not be inlined into a fragile function.
if (Caller->isFragile() && !Callee->isFragile()) {
DEBUG(llvm::dbgs() << " FAIL: Can't inline fragile " <<
Callee->getName() << ".\n");
return nullptr;
}
// Inlining self-recursive functions into other functions can result
// in excessive code duplication since we run the inliner multiple
// times in our pipeline
if (calleeIsSelfRecursive(Callee)) {
DEBUG(llvm::dbgs() << " FAIL: Callee is self-recursive in "
<< Callee->getName() << ".\n");
return nullptr;
}
DEBUG(llvm::dbgs() << " Eligible callee: " <<
Callee->getName() << "\n");
return Callee;
}
static void checkStaticExclusivity(SILFunction &Fn, PostOrderFunctionInfo *PO,
AccessSummaryAnalysis *ASA) {
// The implementation relies on the following SIL invariants:
// - All incoming edges to a block must have the same in-progress
// accesses. This enables the analysis to not perform a data flow merge
// on incoming edges.
// - Further, for a given address each of the in-progress
// accesses must have begun in the same order on all edges. This ensures
// consistent diagnostics across changes to the exploration of the CFG.
// - On return from a function there are no in-progress accesses. This
// enables a sanity check for lean analysis state at function exit.
// - Each end_access instruction corresponds to exactly one begin access
// instruction. (This is encoded in the EndAccessInst itself)
// - begin_access arguments cannot be basic block arguments.
// This enables the analysis to look back to find the *single* storage
// storage location accessed.
if (Fn.empty())
return;
// Collects calls the Standard Library swap() for Fix-Its.
llvm::SmallVector<ApplyInst *, 8> CallsToSwap;
// Stores the accesses that have been found to conflict. Used to defer
// emitting diagnostics until we can determine whether they should
// be suppressed.
llvm::SmallVector<ConflictingAccess, 4> ConflictingAccesses;
// For each basic block, track the stack of current accesses on
// exit from that block.
llvm::SmallDenseMap<SILBasicBlock *, Optional<StorageMap>, 32>
BlockOutAccesses;
BlockOutAccesses[Fn.getEntryBlock()] = StorageMap();
for (auto *BB : PO->getReversePostOrder()) {
Optional<StorageMap> &BBState = BlockOutAccesses[BB];
// Because we use a reverse post-order traversal, unless this is the entry
// at least one of its predecessors must have been reached. Use the out
// state for that predecessor as our in state. The SIL verifier guarantees
// that all incoming edges must have the same current accesses.
for (auto *Pred : BB->getPredecessorBlocks()) {
auto it = BlockOutAccesses.find(Pred);
if (it == BlockOutAccesses.end())
continue;
const Optional<StorageMap> &PredAccesses = it->getSecond();
if (PredAccesses) {
BBState = PredAccesses;
break;
}
}
// The in-progress accesses for the current program point, represented
// as map from storage locations to the accesses in progress for the
// location.
StorageMap &Accesses = *BBState;
for (auto &I : *BB) {
// Apply transfer functions. Beginning an access
// increments the read or write count for the storage location;
// Ending onr decrements the count.
if (auto *BAI = dyn_cast<BeginAccessInst>(&I)) {
SILAccessKind Kind = BAI->getAccessKind();
const AccessedStorage &Storage = findAccessedStorage(BAI->getSource());
AccessInfo &Info = Accesses[Storage];
const IndexTrieNode *SubPath = ASA->findSubPathAccessed(BAI);
if (auto Conflict = shouldReportAccess(Info, Kind, SubPath)) {
ConflictingAccesses.emplace_back(Storage, *Conflict,
RecordedAccess(BAI, SubPath));
}
Info.beginAccess(BAI, SubPath);
continue;
}
if (auto *EAI = dyn_cast<EndAccessInst>(&I)) {
auto It = Accesses.find(findAccessedStorage(EAI->getSource()));
AccessInfo &Info = It->getSecond();
BeginAccessInst *BAI = EAI->getBeginAccess();
const IndexTrieNode *SubPath = ASA->findSubPathAccessed(BAI);
Info.endAccess(EAI, SubPath);
// If the storage location has no more in-progress accesses, remove
// it to keep the StorageMap lean.
if (!Info.hasAccessesInProgress())
Accesses.erase(It);
continue;
}
if (auto *AI = dyn_cast<ApplyInst>(&I)) {
// Record calls to swap() for potential Fix-Its.
if (isCallToStandardLibrarySwap(AI, Fn.getASTContext()))
CallsToSwap.push_back(AI);
else
checkForViolationsInNoEscapeClosures(Accesses, AI, ASA,
ConflictingAccesses);
continue;
}
if (auto *TAI = dyn_cast<TryApplyInst>(&I)) {
checkForViolationsInNoEscapeClosures(Accesses, TAI, ASA,
ConflictingAccesses);
continue;
}
// Sanity check to make sure entries are properly removed.
assert((!isa<ReturnInst>(&I) || Accesses.size() == 0) &&
"Entries were not properly removed?!");
}
}
// Now that we've collected violations and suppressed calls, emit
// diagnostics.
for (auto &Violation : ConflictingAccesses) {
diagnoseExclusivityViolation(Violation, CallsToSwap, Fn.getASTContext());
}
}
// Returns the callee of an apply_inst if it is basically inlineable.
SILFunction *SILPerformanceInliner::getEligibleFunction(FullApplySite AI) {
SILFunction *Callee = AI.getReferencedFunction();
if (!Callee) {
return nullptr;
}
// Don't inline functions that are marked with the @_semantics or @effects
// attribute if the inliner is asked not to inline them.
if (Callee->hasSemanticsAttrs() || Callee->hasEffectsKind()) {
if (WhatToInline == InlineSelection::NoSemanticsAndGlobalInit) {
return nullptr;
}
// The "availability" semantics attribute is treated like global-init.
if (Callee->hasSemanticsAttrs() &&
WhatToInline != InlineSelection::Everything &&
Callee->hasSemanticsAttrThatStartsWith("availability")) {
return nullptr;
}
} else if (Callee->isGlobalInit()) {
if (WhatToInline != InlineSelection::Everything) {
return nullptr;
}
}
// We can't inline external declarations.
if (Callee->empty() || Callee->isExternalDeclaration()) {
return nullptr;
}
// Explicitly disabled inlining.
if (Callee->getInlineStrategy() == NoInline) {
return nullptr;
}
if (!Callee->shouldOptimize()) {
return nullptr;
}
// We don't support this yet.
if (AI.hasSubstitutions())
return nullptr;
SILFunction *Caller = AI.getFunction();
// We don't support inlining a function that binds dynamic self because we
// have no mechanism to preserve the original function's local self metadata.
if (mayBindDynamicSelf(Callee)) {
// Check if passed Self is the same as the Self of the caller.
// In this case, it is safe to inline because both functions
// use the same Self.
if (AI.hasSelfArgument() && Caller->hasSelfParam()) {
auto CalleeSelf = stripCasts(AI.getSelfArgument());
auto CallerSelf = Caller->getSelfArgument();
if (CalleeSelf != SILValue(CallerSelf))
return nullptr;
} else
return nullptr;
}
// Detect self-recursive calls.
if (Caller == Callee) {
return nullptr;
}
// A non-fragile function may not be inlined into a fragile function.
if (Caller->isFragile() &&
!Callee->hasValidLinkageForFragileInline()) {
if (!Callee->hasValidLinkageForFragileRef()) {
llvm::errs() << "caller: " << Caller->getName() << "\n";
llvm::errs() << "callee: " << Callee->getName() << "\n";
llvm_unreachable("Should never be inlining a resilient function into "
"a fragile function");
}
return nullptr;
}
// Inlining self-recursive functions into other functions can result
// in excessive code duplication since we run the inliner multiple
// times in our pipeline
if (calleeIsSelfRecursive(Callee)) {
return nullptr;
}
return Callee;
}
