bool FunctionSignatureTransform::OwnedToGuaranteedAnalyzeResults() {
auto fnConv = F->getConventions();
// For now, only do anything if there's a single direct result.
if (fnConv.getNumDirectSILResults() != 1)
return false;
bool SignatureOptimize = false;
if (ResultDescList[0].hasConvention(ResultConvention::Owned)) {
auto RV = findReturnValue(F);
if (!RV)
return false;
auto &RI = ResultDescList[0];
// We have an @owned return value, find the epilogue retains now.
auto Retains = EA->get(F)->computeEpilogueARCInstructions(EpilogueARCContext::EpilogueARCKind::Retain, RV);
// We do not need to worry about the throw block, as the return value is only
// going to be used in the return block/normal block of the try_apply
// instruction.
if (!Retains.empty()) {
RI.CalleeRetain = Retains;
SignatureOptimize = true;
RI.OwnedToGuaranteed = true;
}
}
return SignatureOptimize;
}
SILFunctionArgument *SILBasicBlock::createFunctionArgument(SILType Ty,
const ValueDecl *D) {
assert(isEntry() && "Function Arguments can only be in the entry block");
SILFunction *Parent = getParent();
auto OwnershipKind = ValueOwnershipKind(
Parent->getModule(), Ty,
Parent->getConventions().getSILArgumentConvention(getNumArguments()));
return new (getModule()) SILFunctionArgument(this, Ty, OwnershipKind, D);
}
ManagedValue
SILGenFunction::emitGlobalVariableRef(SILLocation loc, VarDecl *var) {
assert(!VarLocs.count(var));
if (isGlobalLazilyInitialized(var)) {
// Call the global accessor to get the variable's address.
SILFunction *accessorFn = SGM.getFunction(
SILDeclRef(var, SILDeclRef::Kind::GlobalAccessor),
NotForDefinition);
SILValue accessor = B.createFunctionRef(loc, accessorFn);
auto accessorTy = accessor->getType().castTo<SILFunctionType>();
(void)accessorTy;
assert(!accessorTy->isPolymorphic()
&& "generic global variable accessors not yet implemented");
SILValue addr = B.createApply(
loc, accessor, accessor->getType(),
accessorFn->getConventions().getSingleSILResultType(), {}, {});
// FIXME: It'd be nice if the result of the accessor was natively an
// address.
addr = B.createPointerToAddress(
loc, addr, getLoweredType(var->getInterfaceType()).getAddressType(),
/*isStrict*/ true, /*isInvariant*/ false);
return ManagedValue::forLValue(addr);
}
// Global variables can be accessed directly with global_addr. Emit this
// instruction into the prolog of the function so we can memoize/CSE it in
// VarLocs.
auto entryBB = getFunction().begin();
SILGenBuilder prologueB(*this, entryBB, entryBB->begin());
prologueB.setTrackingList(B.getTrackingList());
auto *silG = SGM.getSILGlobalVariable(var, NotForDefinition);
SILValue addr = prologueB.createGlobalAddr(var, silG);
VarLocs[var] = SILGenFunction::VarLoc::get(addr);
return ManagedValue::forLValue(addr);
}
/// \brief Populate the body of the cloned closure, modifying instructions as
/// necessary. This is where we create the actual specialized BB Arguments.
void ClosureSpecCloner::populateCloned() {
SILFunction *Cloned = getCloned();
SILFunction *ClosureUser = CallSiteDesc.getApplyCallee();
// Create arguments for the entry block.
SILBasicBlock *ClosureUserEntryBB = &*ClosureUser->begin();
SILBasicBlock *ClonedEntryBB = Cloned->createBasicBlock();
SmallVector<SILValue, 4> entryArgs;
entryArgs.reserve(ClosureUserEntryBB->getArguments().size());
// Remove the closure argument.
SILArgument *ClosureArg = nullptr;
for (size_t i = 0, e = ClosureUserEntryBB->args_size(); i != e; ++i) {
SILArgument *Arg = ClosureUserEntryBB->getArgument(i);
if (i == CallSiteDesc.getClosureIndex()) {
ClosureArg = Arg;
entryArgs.push_back(SILValue());
continue;
}
// Otherwise, create a new argument which copies the original argument
SILValue MappedValue =
ClonedEntryBB->createFunctionArgument(Arg->getType(), Arg->getDecl());
entryArgs.push_back(MappedValue);
}
// Next we need to add in any arguments that are not captured as arguments to
// the cloned function.
//
// We do not insert the new mapped arguments into the value map since there by
// definition is nothing in the partial apply user function that references
// such arguments. After this pass is done the only thing that will reference
// the arguments is the partial apply that we will create.
SILFunction *ClosedOverFun = CallSiteDesc.getClosureCallee();
auto ClosedOverFunConv = ClosedOverFun->getConventions();
unsigned NumTotalParams = ClosedOverFunConv.getNumParameters();
unsigned NumNotCaptured = NumTotalParams - CallSiteDesc.getNumArguments();
llvm::SmallVector<SILValue, 4> NewPAIArgs;
for (auto &PInfo : ClosedOverFunConv.getParameters().slice(NumNotCaptured)) {
auto paramTy = ClosedOverFunConv.getSILType(PInfo);
SILValue MappedValue = ClonedEntryBB->createFunctionArgument(paramTy);
NewPAIArgs.push_back(MappedValue);
}
SILBuilder &Builder = getBuilder();
Builder.setInsertionPoint(ClonedEntryBB);
// Clone FRI and PAI, and replace usage of the removed closure argument
// with result of cloned PAI.
SILValue FnVal =
Builder.createFunctionRef(CallSiteDesc.getLoc(), ClosedOverFun);
auto *NewClosure = CallSiteDesc.createNewClosure(Builder, FnVal, NewPAIArgs);
// Clone a chain of ConvertFunctionInsts. This can create further
// reabstraction partial_apply instructions.
SmallVector<PartialApplyInst*, 4> NeedsRelease;
SILValue ConvertedCallee = cloneCalleeConversion(
CallSiteDesc.getClosureCallerArg(), NewClosure, Builder, NeedsRelease);
// Make sure that we actually emit the releases for reabstraction thunks. We
// have guaranteed earlier that we only allow reabstraction thunks if the
// closure was passed trivial.
assert(NeedsRelease.empty() || CallSiteDesc.isTrivialNoEscapeParameter());
entryArgs[CallSiteDesc.getClosureIndex()] = ConvertedCallee;
// Visit original BBs in depth-first preorder, starting with the
// entry block, cloning all instructions and terminators.
cloneFunctionBody(ClosureUser, ClonedEntryBB, entryArgs);
// Then insert a release in all non failure exit BBs if our partial apply was
// guaranteed. This is b/c it was passed at +0 originally and we need to
// balance the initial increment of the newly created closure(s).
bool ClosureHasRefSemantics = CallSiteDesc.closureHasRefSemanticContext();
if ((CallSiteDesc.isClosureGuaranteed() ||
CallSiteDesc.isTrivialNoEscapeParameter()) &&
(ClosureHasRefSemantics || !NeedsRelease.empty())) {
for (SILBasicBlock *BB : CallSiteDesc.getNonFailureExitBBs()) {
SILBasicBlock *OpBB = getOpBasicBlock(BB);
TermInst *TI = OpBB->getTerminator();
auto Loc = CleanupLocation::get(NewClosure->getLoc());
// If we have an exit, we place the release right before it so we know
// that it will be executed at the end of the epilogue.
if (TI->isFunctionExiting()) {
Builder.setInsertionPoint(TI);
if (ClosureHasRefSemantics)
Builder.createReleaseValue(Loc, SILValue(NewClosure),
Builder.getDefaultAtomicity());
for (auto PAI : NeedsRelease)
Builder.createReleaseValue(Loc, SILValue(PAI),
Builder.getDefaultAtomicity());
continue;
}
// We use casts where findAllNonFailureExitBBs should have made sure that
// this is true. This will ensure that the code is updated when we hit the
// cast failure in debug builds.
auto *Unreachable = cast<UnreachableInst>(TI);
auto PrevIter = std::prev(SILBasicBlock::iterator(Unreachable));
auto NoReturnApply = FullApplySite::isa(&*PrevIter);
// We insert the release value right before the no return apply so that if
// the partial apply is passed into the no-return function as an @owned
// value, we will retain the partial apply before we release it and
// potentially eliminate it.
Builder.setInsertionPoint(NoReturnApply.getInstruction());
if (ClosureHasRefSemantics)
Builder.createReleaseValue(Loc, SILValue(NewClosure),
Builder.getDefaultAtomicity());
for (auto PAI : NeedsRelease)
Builder.createReleaseValue(Loc, SILValue(PAI),
Builder.getDefaultAtomicity());
}
}
}
/// In this function we create the actual cloned function and its proper cloned
/// type. But we do not create any body. This implies that the creation of the
/// actual arguments in the function is in populateCloned.
///
/// \arg PAUser The function that is being passed the partial apply.
/// \arg PAI The partial apply that is being passed to PAUser.
/// \arg ClosureIndex The index of the partial apply in PAUser's function
/// signature.
/// \arg ClonedName The name of the cloned function that we will create.
SILFunction *
ClosureSpecCloner::initCloned(SILOptFunctionBuilder &FunctionBuilder,
const CallSiteDescriptor &CallSiteDesc,
StringRef ClonedName) {
SILFunction *ClosureUser = CallSiteDesc.getApplyCallee();
// This is the list of new interface parameters of the cloned function.
llvm::SmallVector<SILParameterInfo, 4> NewParameterInfoList;
// First add to NewParameterInfoList all of the SILParameterInfo in the
// original function except for the closure.
CanSILFunctionType ClosureUserFunTy = ClosureUser->getLoweredFunctionType();
auto ClosureUserConv = ClosureUser->getConventions();
unsigned Index = ClosureUserConv.getSILArgIndexOfFirstParam();
for (auto ¶m : ClosureUserConv.getParameters()) {
if (Index != CallSiteDesc.getClosureIndex())
NewParameterInfoList.push_back(param);
++Index;
}
// Then add any arguments that are captured in the closure to the function's
// argument type. Since they are captured, we need to pass them directly into
// the new specialized function.
SILFunction *ClosedOverFun = CallSiteDesc.getClosureCallee();
auto ClosedOverFunConv = ClosedOverFun->getConventions();
SILModule &M = ClosureUser->getModule();
// Captured parameters are always appended to the function signature. If the
// type of the captured argument is:
// - direct and trivial, pass the argument as Direct_Unowned.
// - direct and non-trivial, pass the argument as Direct_Owned.
// - indirect, pass the argument using the same parameter convention as in the
// original closure.
//
// We use the type of the closure here since we allow for the closure to be an
// external declaration.
unsigned NumTotalParams = ClosedOverFunConv.getNumParameters();
unsigned NumNotCaptured = NumTotalParams - CallSiteDesc.getNumArguments();
for (auto &PInfo : ClosedOverFunConv.getParameters().slice(NumNotCaptured)) {
ParameterConvention ParamConv;
if (PInfo.isFormalIndirect()) {
ParamConv = PInfo.getConvention();
assert(!SILModuleConventions(M).useLoweredAddresses()
|| ParamConv == ParameterConvention::Indirect_Inout
|| ParamConv == ParameterConvention::Indirect_InoutAliasable);
} else {
ParamConv = ClosedOverFunConv.getSILType(PInfo).isTrivial(M)
? ParameterConvention::Direct_Unowned
: ParameterConvention::Direct_Owned;
}
SILParameterInfo NewPInfo(PInfo.getType(), ParamConv);
NewParameterInfoList.push_back(NewPInfo);
}
// The specialized function is always a thin function. This is important
// because we may add additional parameters after the Self parameter of
// witness methods. In this case the new function is not a method anymore.
auto ExtInfo = ClosureUserFunTy->getExtInfo();
ExtInfo = ExtInfo.withRepresentation(SILFunctionTypeRepresentation::Thin);
auto ClonedTy = SILFunctionType::get(
ClosureUserFunTy->getGenericSignature(), ExtInfo,
ClosureUserFunTy->getCoroutineKind(),
ClosureUserFunTy->getCalleeConvention(), NewParameterInfoList,
ClosureUserFunTy->getYields(), ClosureUserFunTy->getResults(),
ClosureUserFunTy->getOptionalErrorResult(), M.getASTContext());
// We make this function bare so we don't have to worry about decls in the
// SILArgument.
auto *Fn = FunctionBuilder.createFunction(
// It's important to use a shared linkage for the specialized function
// and not the original linkage.
// Otherwise the new function could have an external linkage (in case the
// original function was de-serialized) and would not be code-gen'd.
// It's also important to disconnect this specialized function from any
// classes (the classSubclassScope), because that may incorrectly
// influence the linkage.
getSpecializedLinkage(ClosureUser, ClosureUser->getLinkage()), ClonedName,
ClonedTy, ClosureUser->getGenericEnvironment(),
ClosureUser->getLocation(), IsBare, ClosureUser->isTransparent(),
CallSiteDesc.isSerialized(), IsNotDynamic, ClosureUser->getEntryCount(),
ClosureUser->isThunk(),
/*classSubclassScope=*/SubclassScope::NotApplicable,
ClosureUser->getInlineStrategy(), ClosureUser->getEffectsKind(),
ClosureUser, ClosureUser->getDebugScope());
if (!ClosureUser->hasQualifiedOwnership()) {
Fn->setUnqualifiedOwnership();
}
for (auto &Attr : ClosureUser->getSemanticsAttrs())
Fn->addSemanticsAttr(Attr);
return Fn;
}
void FunctionSignatureTransform::createFunctionSignatureOptimizedFunction() {
// Create the optimized function !
SILModule &M = F->getModule();
std::string Name = createOptimizedSILFunctionName();
SILLinkage linkage = F->getLinkage();
if (isAvailableExternally(linkage))
linkage = SILLinkage::Shared;
DEBUG(llvm::dbgs() << " -> create specialized function " << Name << "\n");
NewF = M.createFunction(linkage, Name, createOptimizedSILFunctionType(),
F->getGenericEnvironment(), F->getLocation(),
F->isBare(), F->isTransparent(), F->isSerialized(),
F->isThunk(), F->getClassVisibility(),
F->getInlineStrategy(), F->getEffectsKind(), nullptr,
F->getDebugScope());
if (F->hasUnqualifiedOwnership()) {
NewF->setUnqualifiedOwnership();
}
// Then we transfer the body of F to NewF.
NewF->spliceBody(F);
// Array semantic clients rely on the signature being as in the original
// version.
for (auto &Attr : F->getSemanticsAttrs()) {
if (!StringRef(Attr).startswith("array."))
NewF->addSemanticsAttr(Attr);
}
// Do the last bit of work to the newly created optimized function.
ArgumentExplosionFinalizeOptimizedFunction();
DeadArgumentFinalizeOptimizedFunction();
// Create the thunk body !
F->setThunk(IsThunk);
// The thunk now carries the information on how the signature is
// optimized. If we inline the thunk, we will get the benefit of calling
// the signature optimized function without additional setup on the
// caller side.
F->setInlineStrategy(AlwaysInline);
SILBasicBlock *ThunkBody = F->createBasicBlock();
for (auto &ArgDesc : ArgumentDescList) {
ThunkBody->createFunctionArgument(ArgDesc.Arg->getType(), ArgDesc.Decl);
}
SILLocation Loc = ThunkBody->getParent()->getLocation();
SILBuilder Builder(ThunkBody);
Builder.setCurrentDebugScope(ThunkBody->getParent()->getDebugScope());
FunctionRefInst *FRI = Builder.createFunctionRef(Loc, NewF);
// Create the args for the thunk's apply, ignoring any dead arguments.
llvm::SmallVector<SILValue, 8> ThunkArgs;
for (auto &ArgDesc : ArgumentDescList) {
addThunkArgument(ArgDesc, Builder, ThunkBody, ThunkArgs);
}
// We are ignoring generic functions and functions with out parameters for
// now.
SILValue ReturnValue;
SILType LoweredType = NewF->getLoweredType();
SILType ResultType = NewF->getConventions().getSILResultType();
auto FunctionTy = LoweredType.castTo<SILFunctionType>();
if (FunctionTy->hasErrorResult()) {
// We need a try_apply to call a function with an error result.
SILFunction *Thunk = ThunkBody->getParent();
SILBasicBlock *NormalBlock = Thunk->createBasicBlock();
ReturnValue =
NormalBlock->createPHIArgument(ResultType, ValueOwnershipKind::Owned);
SILBasicBlock *ErrorBlock = Thunk->createBasicBlock();
SILType Error =
SILType::getPrimitiveObjectType(FunctionTy->getErrorResult().getType());
auto *ErrorArg =
ErrorBlock->createPHIArgument(Error, ValueOwnershipKind::Owned);
Builder.createTryApply(Loc, FRI, LoweredType, SubstitutionList(),
ThunkArgs, NormalBlock, ErrorBlock);
Builder.setInsertionPoint(ErrorBlock);
Builder.createThrow(Loc, ErrorArg);
Builder.setInsertionPoint(NormalBlock);
} else {
ReturnValue = Builder.createApply(Loc, FRI, LoweredType, ResultType,
SubstitutionList(), ThunkArgs,
false);
}
// Set up the return results.
if (NewF->isNoReturnFunction()) {
Builder.createUnreachable(Loc);
} else {
Builder.createReturn(Loc, ReturnValue);
}
// Do the last bit work to finalize the thunk.
OwnedToGuaranteedFinalizeThunkFunction(Builder, F);
assert(F->getDebugScope()->Parent != NewF->getDebugScope()->Parent);
}
