void irgen::emitTypeLayoutVerifier(IRGenFunction &IGF, ArrayRef<CanType> formalTypes) { llvm::Type *verifierArgTys[] = { IGF.IGM.TypeMetadataPtrTy, IGF.IGM.Int8PtrTy, IGF.IGM.Int8PtrTy, IGF.IGM.SizeTy, IGF.IGM.Int8PtrTy, }; auto verifierFnTy = llvm::FunctionType::get(IGF.IGM.VoidTy, verifierArgTys, /*var arg*/ false); auto verifierFn = IGF.IGM.Module.getOrInsertFunction( "_swift_debug_verifyTypeLayoutAttribute", verifierFnTy); struct VerifierArgumentBuffers { Address runtimeBuf, staticBuf; }; llvm::DenseMap<llvm::Type *, VerifierArgumentBuffers> verifierArgBufs; auto getSizeConstant = [&](Size sz) -> llvm::Constant * { return llvm::ConstantInt::get(IGF.IGM.SizeTy, sz.getValue()); }; auto getAlignmentMaskConstant = [&](Alignment a) -> llvm::Constant * { return llvm::ConstantInt::get(IGF.IGM.SizeTy, a.getValue() - 1); }; auto getBoolConstant = [&](bool b) -> llvm::Constant * { return llvm::ConstantInt::get(IGF.IGM.Int1Ty, b); }; SmallString<20> numberBuf; for (auto formalType : formalTypes) { // Runtime type metadata always represents the maximal abstraction level of // the type. auto anyTy = ProtocolCompositionType::get(IGF.IGM.Context, {}); auto openedAnyTy = ArchetypeType::getOpened(anyTy); auto maxAbstraction = AbstractionPattern(openedAnyTy); auto &ti = IGF.getTypeInfoForUnlowered(maxAbstraction, formalType); // If there's no fixed type info, we rely on the runtime anyway, so there's // nothing to verify. // TODO: There are some traits of partially-fixed layouts we could check too. auto *fixedTI = dyn_cast<FixedTypeInfo>(&ti); if (!fixedTI) return; auto metadata = IGF.emitTypeMetadataRef(formalType); auto verify = [&](llvm::Value *runtimeVal, llvm::Value *staticVal, const llvm::Twine &description) { assert(runtimeVal->getType() == staticVal->getType()); // Get or create buffers for the arguments. VerifierArgumentBuffers bufs; auto foundBufs = verifierArgBufs.find(runtimeVal->getType()); if (foundBufs != verifierArgBufs.end()) { bufs = foundBufs->second; } else { Address runtimeBuf = IGF.createAlloca(runtimeVal->getType(), IGF.IGM.getPointerAlignment(), "runtime"); Address staticBuf = IGF.createAlloca(staticVal->getType(), IGF.IGM.getPointerAlignment(), "static"); bufs = {runtimeBuf, staticBuf}; verifierArgBufs[runtimeVal->getType()] = bufs; } IGF.Builder.CreateStore(runtimeVal, bufs.runtimeBuf); IGF.Builder.CreateStore(staticVal, bufs.staticBuf); auto runtimePtr = IGF.Builder.CreateBitCast(bufs.runtimeBuf.getAddress(), IGF.IGM.Int8PtrTy); auto staticPtr = IGF.Builder.CreateBitCast(bufs.staticBuf.getAddress(), IGF.IGM.Int8PtrTy); auto count = llvm::ConstantInt::get(IGF.IGM.SizeTy, IGF.IGM.DataLayout.getTypeStoreSize(runtimeVal->getType())); auto msg = IGF.IGM.getAddrOfGlobalString(description.str()); IGF.Builder.CreateCall( verifierFn, {metadata, runtimePtr, staticPtr, count, msg}); }; // Check that the fixed layout matches the runtime layout. SILType layoutType = SILType::getPrimitiveObjectType(formalType); verify(emitLoadOfSize(IGF, layoutType), getSizeConstant(fixedTI->getFixedSize()), "size"); verify(emitLoadOfAlignmentMask(IGF, layoutType), getAlignmentMaskConstant(fixedTI->getFixedAlignment()), "alignment mask"); verify(emitLoadOfStride(IGF, layoutType), getSizeConstant(fixedTI->getFixedStride()), "stride"); verify(emitLoadOfIsInline(IGF, layoutType), getBoolConstant(fixedTI->getFixedPacking(IGF.IGM) == FixedPacking::OffsetZero), "is-inline bit"); verify(emitLoadOfIsPOD(IGF, layoutType), getBoolConstant(fixedTI->isPOD(ResilienceScope::Component)), "is-POD bit"); verify(emitLoadOfIsBitwiseTakable(IGF, layoutType), getBoolConstant(fixedTI->isBitwiseTakable(ResilienceScope::Component)), "is-bitwise-takable bit"); unsigned xiCount = fixedTI->getFixedExtraInhabitantCount(IGF.IGM); verify(emitLoadOfHasExtraInhabitants(IGF, layoutType), getBoolConstant(xiCount != 0), "has-extra-inhabitants bit"); // Check extra inhabitants. if (xiCount > 0) { verify(emitLoadOfExtraInhabitantCount(IGF, layoutType), getSizeConstant(Size(xiCount)), "extra inhabitant count"); // Verify that the extra inhabitant representations are consistent. /* TODO: Update for EnumPayload implementation changes. auto xiBuf = IGF.createAlloca(fixedTI->getStorageType(), fixedTI->getFixedAlignment(), "extra-inhabitant"); auto xiOpaque = IGF.Builder.CreateBitCast(xiBuf, IGF.IGM.OpaquePtrTy); // TODO: Randomize the set of extra inhabitants we check. unsigned bits = fixedTI->getFixedSize().getValueInBits(); for (unsigned i = 0, e = std::min(xiCount, 1024u); i < e; ++i) { // Initialize the buffer with junk, to help ensure we're insensitive to // insignificant bits. // TODO: Randomize the filler. IGF.Builder.CreateMemSet(xiBuf.getAddress(), llvm::ConstantInt::get(IGF.IGM.Int8Ty, 0x5A), fixedTI->getFixedSize().getValue(), fixedTI->getFixedAlignment().getValue()); // Ask the runtime to store an extra inhabitant. auto index = llvm::ConstantInt::get(IGF.IGM.Int32Ty, i); emitStoreExtraInhabitantCall(IGF, layoutType, index, xiOpaque.getAddress()); // Compare the stored extra inhabitant against the fixed extra // inhabitant pattern. auto fixedXI = fixedTI->getFixedExtraInhabitantValue(IGF.IGM, bits, i); auto xiBuf2 = IGF.Builder.CreateBitCast(xiBuf, fixedXI->getType()->getPointerTo()); llvm::Value *runtimeXI = IGF.Builder.CreateLoad(xiBuf2); runtimeXI = fixedTI->maskFixedExtraInhabitant(IGF, runtimeXI); numberBuf.clear(); { llvm::raw_svector_ostream os(numberBuf); os << i; os.flush(); } verify(runtimeXI, fixedXI, llvm::Twine("stored extra inhabitant ") + numberBuf.str()); // Now store the fixed extra inhabitant and ask the runtime to identify // it. // Mask in junk to make sure the runtime correctly ignores it. auto xiMask = fixedTI->getFixedExtraInhabitantMask(IGF.IGM).asAPInt(); auto maskVal = llvm::ConstantInt::get(IGF.IGM.getLLVMContext(), xiMask); auto notMaskVal = llvm::ConstantInt::get(IGF.IGM.getLLVMContext(), ~xiMask); // TODO: Randomize the filler. auto xiFill = llvm::ConstantInt::getAllOnesValue(fixedXI->getType()); llvm::Value *xiFillMask = IGF.Builder.CreateAnd(notMaskVal, xiFill); llvm::Value *xiValMask = IGF.Builder.CreateAnd(maskVal, fixedXI); llvm::Value *filledXI = IGF.Builder.CreateOr(xiFillMask, xiValMask); IGF.Builder.CreateStore(filledXI, xiBuf2); auto runtimeIndex = emitGetExtraInhabitantIndexCall(IGF, layoutType, xiOpaque.getAddress()); verify(runtimeIndex, index, llvm::Twine("extra inhabitant index calculation ") + numberBuf.str()); } */ } // TODO: Verify interesting layout properties specific to the kind of type, // such as struct or class field offsets, enum case tags, vtable entries, // etc. } }
void LocalTypeDataCache:: addAbstractForFulfillments(IRGenFunction &IGF, FulfillmentMap &&fulfillments, llvm::function_ref<AbstractSource()> createSource) { // Add the source lazily. Optional<unsigned> sourceIndex; auto getSourceIndex = [&]() -> unsigned { if (!sourceIndex) { AbstractSources.emplace_back(createSource()); sourceIndex = AbstractSources.size() - 1; } return *sourceIndex; }; for (auto &fulfillment : fulfillments) { CanType type = CanType(fulfillment.first.first); LocalTypeDataKind localDataKind; // For now, ignore witness-table fulfillments when they're not for // archetypes. if (ProtocolDecl *protocol = fulfillment.first.second) { if (auto archetype = dyn_cast<ArchetypeType>(type)) { auto conformsTo = archetype->getConformsTo(); auto it = std::find(conformsTo.begin(), conformsTo.end(), protocol); if (it == conformsTo.end()) continue; localDataKind = LocalTypeDataKind::forAbstractProtocolWitnessTable(*it); } else { continue; } } else { // Ignore type metadata fulfillments for non-dependent types that // we can produce very cheaply. We don't want to end up emitting // the type metadata for Int by chasing through N layers of metadata // just because that path happens to be in the cache. if (!type->hasArchetype() && getTypeMetadataAccessStrategy(IGF.IGM, type, /*preferDirect*/ true) == MetadataAccessStrategy::Direct) { continue; } localDataKind = LocalTypeDataKind::forTypeMetadata(); } // Find the chain for the key. auto key = getKey(type, localDataKind); auto &chain = Map[key]; // Check whether there's already an entry that's at least as good as the // fulfillment. Optional<unsigned> fulfillmentCost; auto getFulfillmentCost = [&]() -> unsigned { if (!fulfillmentCost) fulfillmentCost = fulfillment.second.Path.cost(); return *fulfillmentCost; }; bool isConditional = IGF.isConditionalDominancePoint(); bool foundBetter = false; for (CacheEntry *cur = chain.Root, *last = nullptr; cur; last = cur, cur = cur->getNext()) { // Ensure the entry is acceptable. if (!IGF.isActiveDominancePointDominatedBy(cur->DefinitionPoint)) continue; // Ensure that the entry isn't better than the fulfillment. auto curCost = cur->cost(); if (curCost == 0 || curCost <= getFulfillmentCost()) { foundBetter = true; break; } // If the entry is defined at the current point, (1) we know there // won't be a better entry and (2) we should remove it. if (cur->DefinitionPoint == IGF.getActiveDominancePoint() && !isConditional) { // Splice it out of the chain. assert(!cur->isConditional()); chain.eraseEntry(last, cur); break; } } if (foundBetter) continue; // Okay, make a new entry. // Register with the conditional dominance scope if necessary. if (isConditional) { IGF.registerConditionalLocalTypeDataKey(key); } // Allocate the new entry. auto newEntry = new AbstractCacheEntry(IGF.getActiveDominancePoint(), isConditional, getSourceIndex(), std::move(fulfillment.second.Path)); // Add it to the front of the chain. chain.push_front(newEntry); } }
MetadataResponse LocalTypeDataCache::tryGet(IRGenFunction &IGF, LocalTypeDataKey key, bool allowAbstract, DynamicMetadataRequest request) { // Use the caching key. key = key.getCachingKey(); auto it = Map.find(key); if (it == Map.end()) return MetadataResponse(); auto &chain = it->second; CacheEntry *best = nullptr; Optional<OperationCost> bestCost; CacheEntry *next = chain.Root; while (next) { CacheEntry *cur = next; next = cur->getNext(); // Ignore abstract entries if so requested. if (!allowAbstract && !isa<ConcreteCacheEntry>(cur)) continue; // Ignore unacceptable entries. if (!IGF.isActiveDominancePointDominatedBy(cur->DefinitionPoint)) continue; // If there's a collision, compare by cost, ignoring higher-cost entries. if (best) { // Compute the cost of the best entry if we haven't done so already. // If that's zero, go ahead and short-circuit out. if (!bestCost) { bestCost = best->costForRequest(key, request); if (*bestCost == OperationCost::Free) break; } auto curCost = cur->costForRequest(key, request); if (curCost >= *bestCost) continue; // Replace the best cost and fall through. bestCost = curCost; } best = cur; } // If we didn't find anything, we're done. if (!best) return MetadataResponse(); // Okay, we've found the best entry available. switch (best->getKind()) { // For concrete caches, this is easy. case CacheEntry::Kind::Concrete: { auto entry = cast<ConcreteCacheEntry>(best); if (entry->immediatelySatisfies(key, request)) return entry->Value; assert(key.Kind.isAnyTypeMetadata()); // Emit a dynamic check that the type metadata matches the request. // TODO: we could potentially end up calling this redundantly with a // dynamic request. Fortunately, those are used only in very narrow // circumstances. auto response = emitCheckTypeMetadataState(IGF, request, entry->Value); // Add a concrete entry for the checked result. IGF.setScopedLocalTypeData(key, response); return response; } // For abstract caches, we need to follow a path. case CacheEntry::Kind::Abstract: { auto entry = cast<AbstractCacheEntry>(best); // Follow the path. auto &source = AbstractSources[entry->SourceIndex]; auto response = entry->follow(IGF, source, request); // Following the path automatically caches at every point along it, // including the end. assert(chain.Root->DefinitionPoint == IGF.getActiveDominancePoint()); assert(isa<ConcreteCacheEntry>(chain.Root)); return response; } } llvm_unreachable("bad cache entry kind"); }
/// Emit a checked cast to a protocol or protocol composition. void irgen::emitScalarExistentialDowncast(IRGenFunction &IGF, llvm::Value *value, SILType srcType, SILType destType, CheckedCastMode mode, Optional<MetatypeRepresentation> metatypeKind, Explosion &ex) { SmallVector<ProtocolDecl*, 4> allProtos; destType.getSwiftRValueType().getAnyExistentialTypeProtocols(allProtos); // Look up witness tables for the protocols that need them and get // references to the ObjC Protocol* values for the objc protocols. SmallVector<llvm::Value*, 4> objcProtos; SmallVector<llvm::Value*, 4> witnessTableProtos; bool hasClassConstraint = false; bool hasClassConstraintByProtocol = false; for (auto proto : allProtos) { // If the protocol introduces a class constraint, track whether we need // to check for it independent of protocol witnesses. if (proto->requiresClass()) { hasClassConstraint = true; if (proto->getKnownProtocolKind() && *proto->getKnownProtocolKind() == KnownProtocolKind::AnyObject) { // AnyObject only requires that the type be a class. continue; } // If this protocol is class-constrained but not AnyObject, checking its // conformance will check the class constraint too. hasClassConstraintByProtocol = true; } if (Lowering::TypeConverter::protocolRequiresWitnessTable(proto)) { auto descriptor = emitProtocolDescriptorRef(IGF, proto); witnessTableProtos.push_back(descriptor); } if (!proto->isObjC()) continue; objcProtos.push_back(emitReferenceToObjCProtocol(IGF, proto)); } llvm::Type *resultType; if (metatypeKind) { switch (*metatypeKind) { case MetatypeRepresentation::Thin: llvm_unreachable("can't cast to thin metatype"); case MetatypeRepresentation::Thick: resultType = IGF.IGM.TypeMetadataPtrTy; break; case MetatypeRepresentation::ObjC: resultType = IGF.IGM.ObjCClassPtrTy; break; } } else { auto schema = IGF.getTypeInfo(destType).getSchema(); resultType = schema[0].getScalarType(); } // We only need to check the class constraint for metatype casts where // no protocol conformance indirectly requires the constraint for us. bool checkClassConstraint = (bool)metatypeKind && hasClassConstraint && !hasClassConstraintByProtocol; llvm::Value *resultValue = value; // If we don't have anything we really need to check, then trivially succeed. if (objcProtos.empty() && witnessTableProtos.empty() && !checkClassConstraint) { resultValue = IGF.Builder.CreateBitCast(value, resultType); ex.add(resultValue); return; } // Check the ObjC protocol conformances if there were any. llvm::Value *objcCast = nullptr; if (!objcProtos.empty()) { // Get the ObjC instance or class object to check for these conformances. llvm::Value *objcObject; if (metatypeKind) { switch (*metatypeKind) { case MetatypeRepresentation::Thin: llvm_unreachable("can't cast to thin metatype"); case MetatypeRepresentation::Thick: { // The metadata might be for a non-class type, which wouldn't have // an ObjC class object. objcObject = nullptr; break; } case MetatypeRepresentation::ObjC: // Metatype is already an ObjC object. objcObject = value; break; } } else { // Class instance is already an ObjC object. objcObject = value; } if (objcObject) objcObject = IGF.Builder.CreateBitCast(objcObject, IGF.IGM.UnknownRefCountedPtrTy); // Pick the cast function based on the cast mode and on whether we're // casting a Swift metatype or ObjC object. llvm::Value *castFn; switch (mode) { case CheckedCastMode::Unconditional: castFn = objcObject ? IGF.IGM.getDynamicCastObjCProtocolUnconditionalFn() : IGF.IGM.getDynamicCastTypeToObjCProtocolUnconditionalFn(); break; case CheckedCastMode::Conditional: castFn = objcObject ? IGF.IGM.getDynamicCastObjCProtocolConditionalFn() : IGF.IGM.getDynamicCastTypeToObjCProtocolConditionalFn(); break; } llvm::Value *objcCastObject = objcObject ? objcObject : value; Address protoRefsBuf = IGF.createAlloca( llvm::ArrayType::get(IGF.IGM.Int8PtrTy, objcProtos.size()), IGF.IGM.getPointerAlignment(), "objc_protocols"); protoRefsBuf = IGF.Builder.CreateBitCast(protoRefsBuf, IGF.IGM.Int8PtrPtrTy); for (unsigned index : indices(objcProtos)) { Address protoRefSlot = IGF.Builder.CreateConstArrayGEP( protoRefsBuf, index, IGF.IGM.getPointerSize()); IGF.Builder.CreateStore(objcProtos[index], protoRefSlot); ++index; } objcCast = IGF.Builder.CreateCall( castFn, {objcCastObject, IGF.IGM.getSize(Size(objcProtos.size())), protoRefsBuf.getAddress()}); resultValue = IGF.Builder.CreateBitCast(objcCast, resultType); } // If we don't need to look up any witness tables, we're done. if (witnessTableProtos.empty() && !checkClassConstraint) { ex.add(resultValue); return; } // If we're doing a conditional cast, and the ObjC protocol checks failed, // then the cast is done. Optional<ConditionalDominanceScope> condition; llvm::BasicBlock *origBB = nullptr, *successBB = nullptr, *contBB = nullptr; if (!objcProtos.empty()) { switch (mode) { case CheckedCastMode::Unconditional: break; case CheckedCastMode::Conditional: { origBB = IGF.Builder.GetInsertBlock(); successBB = IGF.createBasicBlock("success"); contBB = IGF.createBasicBlock("cont"); auto isNull = IGF.Builder.CreateICmpEQ(objcCast, llvm::ConstantPointerNull::get( cast<llvm::PointerType>(objcCast->getType()))); IGF.Builder.CreateCondBr(isNull, contBB, successBB); IGF.Builder.emitBlock(successBB); condition.emplace(IGF); } } } // Get the Swift type metadata for the type. llvm::Value *metadataValue; if (metatypeKind) { switch (*metatypeKind) { case MetatypeRepresentation::Thin: llvm_unreachable("can't cast to thin metatype"); case MetatypeRepresentation::Thick: // The value is already a native metatype. metadataValue = value; break; case MetatypeRepresentation::ObjC: // Get the type metadata from the ObjC class, which may be a wrapper. metadataValue = emitObjCMetadataRefForMetadata(IGF, value); } } else { // Get the type metadata for the instance. metadataValue = emitDynamicTypeOfHeapObject(IGF, value, srcType); } // Look up witness tables for the protocols that need them. auto fn = emitExistentialScalarCastFn(IGF.IGM, witnessTableProtos.size(), mode, checkClassConstraint); llvm::SmallVector<llvm::Value *, 4> args; if (resultValue->getType() != IGF.IGM.Int8PtrTy) resultValue = IGF.Builder.CreateBitCast(resultValue, IGF.IGM.Int8PtrTy); args.push_back(resultValue); args.push_back(metadataValue); for (auto proto : witnessTableProtos) args.push_back(proto); auto valueAndWitnessTables = IGF.Builder.CreateCall(fn, args); resultValue = IGF.Builder.CreateExtractValue(valueAndWitnessTables, 0); if (resultValue->getType() != resultType) resultValue = IGF.Builder.CreateBitCast(resultValue, resultType); ex.add(resultValue); for (unsigned i = 0, e = witnessTableProtos.size(); i < e; ++i) { auto wt = IGF.Builder.CreateExtractValue(valueAndWitnessTables, i + 1); ex.add(wt); } // If we had conditional ObjC checks, join the failure paths. if (contBB) { condition.reset(); IGF.Builder.CreateBr(contBB); IGF.Builder.emitBlock(contBB); // Return null on the failure path. Explosion successEx = std::move(ex); ex.reset(); while (!successEx.empty()) { auto successVal = successEx.claimNext(); auto failureVal = llvm::Constant::getNullValue(successVal->getType()); auto phi = IGF.Builder.CreatePHI(successVal->getType(), 2); phi->addIncoming(successVal, successBB); phi->addIncoming(failureVal, origBB); ex.add(phi); } } }
static void emitSubSwitch(IRGenFunction &IGF, MutableArrayRef<EnumPayload::LazyValue> values, APInt mask, MutableArrayRef<std::pair<APInt, llvm::BasicBlock *>> cases, SwitchDefaultDest dflt) { recur: assert(!values.empty() && "didn't exit out when exhausting all values?!"); assert(!cases.empty() && "switching with no cases?!"); auto &DL = IGF.IGM.DataLayout; auto &pv = values.front(); values = values.slice(1); auto payloadTy = getPayloadType(pv); unsigned size = DL.getTypeSizeInBits(payloadTy); // Grab a chunk of the mask. auto maskPiece = mask.zextOrTrunc(size); mask = mask.lshr(size); // If the piece is zero, this doesn't affect the switch. We can just move // forward and recur. if (maskPiece == 0) { for (auto &casePair : cases) casePair.first = casePair.first.lshr(size); goto recur; } // Force the value we will test. auto v = forcePayloadValue(pv); auto payloadIntTy = llvm::IntegerType::get(IGF.IGM.getLLVMContext(), size); // Need to coerce to integer for 'icmp eq' if it's not already an integer // or pointer. (Switching or masking will also require a cast to integer.) if (!isa<llvm::IntegerType>(v->getType()) && !isa<llvm::PointerType>(v->getType())) v = IGF.Builder.CreateBitOrPointerCast(v, payloadIntTy); // Apply the mask if it's interesting. if (!maskPiece.isAllOnesValue()) { v = IGF.Builder.CreateBitOrPointerCast(v, payloadIntTy); auto maskConstant = llvm::ConstantInt::get(payloadIntTy, maskPiece); v = IGF.Builder.CreateAnd(v, maskConstant); } // Gather the values we will switch over for this payload chunk. // FIXME: std::map is lame. Should hash APInts. std::map<APInt, SmallVector<std::pair<APInt, llvm::BasicBlock*>, 2>, ult> subCases; for (auto casePair : cases) { // Grab a chunk of the value. auto valuePiece = casePair.first.zextOrTrunc(size); // Index the case according to this chunk. subCases[valuePiece].push_back({std::move(casePair.first).lshr(size), casePair.second}); } bool needsAdditionalCases = !values.empty() && mask != 0; SmallVector<std::pair<llvm::BasicBlock *, decltype(cases)>, 2> recursiveCases; auto blockForCases = [&](MutableArrayRef<std::pair<APInt, llvm::BasicBlock*>> cases) -> llvm::BasicBlock * { // If we need to recur, emit a new block. if (needsAdditionalCases) { auto newBB = IGF.createBasicBlock(""); recursiveCases.push_back({newBB, cases}); return newBB; } // Otherwise, we can jump directly to the ultimate destination. assert(cases.size() == 1 && "more than one case for final destination?!"); return cases.front().second; }; // If there's only one case, do a cond_br. if (subCases.size() == 1) { auto &subCase = *subCases.begin(); llvm::BasicBlock *block = blockForCases(subCase.second); // If the default case is unreachable, we don't need to conditionally // branch. if (dflt.getInt()) { IGF.Builder.CreateBr(block); goto next; } auto &valuePiece = subCase.first; llvm::Value *valueConstant = llvm::ConstantInt::get(payloadIntTy, valuePiece); valueConstant = IGF.Builder.CreateBitOrPointerCast(valueConstant, v->getType()); auto cmp = IGF.Builder.CreateICmpEQ(v, valueConstant); IGF.Builder.CreateCondBr(cmp, block, dflt.getPointer()); goto next; } // Otherwise, do a switch. { v = IGF.Builder.CreateBitOrPointerCast(v, payloadIntTy); auto swi = IGF.Builder.CreateSwitch(v, dflt.getPointer(), subCases.size()); for (auto &subCase : subCases) { auto &valuePiece = subCase.first; auto valueConstant = llvm::ConstantInt::get(IGF.IGM.getLLVMContext(), valuePiece); swi->addCase(valueConstant, blockForCases(subCase.second)); } } next: // Emit the recursive cases. for (auto &recursive : recursiveCases) { IGF.Builder.emitBlock(recursive.first); emitSubSwitch(IGF, values, mask, recursive.second, dflt); } }
/// Emit a checked cast to a protocol or protocol composition. void irgen::emitScalarExistentialDowncast(IRGenFunction &IGF, llvm::Value *value, SILType srcType, SILType destType, CheckedCastMode mode, Optional<MetatypeRepresentation> metatypeKind, Explosion &ex) { auto srcInstanceType = srcType.getSwiftRValueType(); auto destInstanceType = destType.getSwiftRValueType(); while (auto metatypeType = dyn_cast<ExistentialMetatypeType>( destInstanceType)) { destInstanceType = metatypeType.getInstanceType(); srcInstanceType = cast<AnyMetatypeType>(srcInstanceType).getInstanceType(); } auto layout = destInstanceType.getExistentialLayout(); // Look up witness tables for the protocols that need them and get // references to the ObjC Protocol* values for the objc protocols. SmallVector<llvm::Value*, 4> objcProtos; SmallVector<llvm::Value*, 4> witnessTableProtos; bool hasClassConstraint = layout.requiresClass(); bool hasClassConstraintByProtocol = false; bool hasSuperclassConstraint = bool(layout.superclass); for (auto protoTy : layout.getProtocols()) { auto *protoDecl = protoTy->getDecl(); // If the protocol introduces a class constraint, track whether we need // to check for it independent of protocol witnesses. if (protoDecl->requiresClass()) { assert(hasClassConstraint); hasClassConstraintByProtocol = true; } if (Lowering::TypeConverter::protocolRequiresWitnessTable(protoDecl)) { auto descriptor = emitProtocolDescriptorRef(IGF, protoDecl); witnessTableProtos.push_back(descriptor); } if (protoDecl->isObjC()) objcProtos.push_back(emitReferenceToObjCProtocol(IGF, protoDecl)); } llvm::Type *resultType; if (metatypeKind) { switch (*metatypeKind) { case MetatypeRepresentation::Thin: llvm_unreachable("can't cast to thin metatype"); case MetatypeRepresentation::Thick: resultType = IGF.IGM.TypeMetadataPtrTy; break; case MetatypeRepresentation::ObjC: resultType = IGF.IGM.ObjCClassPtrTy; break; } } else { auto schema = IGF.getTypeInfo(destType).getSchema(); resultType = schema[0].getScalarType(); } // The source of a scalar cast is statically known to be a class or a // metatype, so we only have to check the class constraint in two cases: // // 1) The destination type has an explicit superclass constraint that is // more derived than what the source type is known to be. // // 2) We are casting between metatypes, in which case the source might // be a non-class metatype. bool checkClassConstraint = false; if ((bool)metatypeKind && hasClassConstraint && !hasClassConstraintByProtocol && !srcInstanceType->mayHaveSuperclass()) checkClassConstraint = true; // If the source has an equal or more derived superclass constraint than // the destination, we can elide the superclass check. // // Note that destInstanceType is always an existential type, so calling // getSuperclass() returns the superclass constraint of the existential, // not the superclass of some concrete class. bool checkSuperclassConstraint = hasSuperclassConstraint && !destInstanceType->getSuperclass()->isExactSuperclassOf(srcInstanceType); if (checkSuperclassConstraint) checkClassConstraint = true; llvm::Value *resultValue = value; // If we don't have anything we really need to check, then trivially succeed. if (objcProtos.empty() && witnessTableProtos.empty() && !checkClassConstraint) { resultValue = IGF.Builder.CreateBitCast(value, resultType); ex.add(resultValue); return; } // Check the ObjC protocol conformances if there were any. llvm::Value *objcCast = nullptr; if (!objcProtos.empty()) { // Get the ObjC instance or class object to check for these conformances. llvm::Value *objcObject; if (metatypeKind) { switch (*metatypeKind) { case MetatypeRepresentation::Thin: llvm_unreachable("can't cast to thin metatype"); case MetatypeRepresentation::Thick: { // The metadata might be for a non-class type, which wouldn't have // an ObjC class object. objcObject = nullptr; break; } case MetatypeRepresentation::ObjC: // Metatype is already an ObjC object. objcObject = value; break; } } else { // Class instance is already an ObjC object. objcObject = value; } if (objcObject) objcObject = IGF.Builder.CreateBitCast(objcObject, IGF.IGM.UnknownRefCountedPtrTy); // Pick the cast function based on the cast mode and on whether we're // casting a Swift metatype or ObjC object. llvm::Constant *castFn; switch (mode) { case CheckedCastMode::Unconditional: castFn = objcObject ? IGF.IGM.getDynamicCastObjCProtocolUnconditionalFn() : IGF.IGM.getDynamicCastTypeToObjCProtocolUnconditionalFn(); break; case CheckedCastMode::Conditional: castFn = objcObject ? IGF.IGM.getDynamicCastObjCProtocolConditionalFn() : IGF.IGM.getDynamicCastTypeToObjCProtocolConditionalFn(); break; } llvm::Value *objcCastObject = objcObject ? objcObject : value; Address protoRefsBuf = IGF.createAlloca( llvm::ArrayType::get(IGF.IGM.Int8PtrTy, objcProtos.size()), IGF.IGM.getPointerAlignment(), "objc_protocols"); protoRefsBuf = IGF.Builder.CreateBitCast(protoRefsBuf, IGF.IGM.Int8PtrPtrTy); for (unsigned index : indices(objcProtos)) { Address protoRefSlot = IGF.Builder.CreateConstArrayGEP( protoRefsBuf, index, IGF.IGM.getPointerSize()); IGF.Builder.CreateStore(objcProtos[index], protoRefSlot); ++index; } auto cc = IGF.IGM.DefaultCC; if (auto fun = dyn_cast<llvm::Function>(castFn)) cc = fun->getCallingConv(); auto call = IGF.Builder.CreateCall( castFn, {objcCastObject, IGF.IGM.getSize(Size(objcProtos.size())), protoRefsBuf.getAddress()}); call->setCallingConv(cc); objcCast = call; resultValue = IGF.Builder.CreateBitCast(objcCast, resultType); } // If we don't need to look up any witness tables, we're done. if (witnessTableProtos.empty() && !checkClassConstraint) { ex.add(resultValue); return; } // If we're doing a conditional cast, and the ObjC protocol checks failed, // then the cast is done. Optional<ConditionalDominanceScope> condition; llvm::BasicBlock *origBB = nullptr, *successBB = nullptr, *contBB = nullptr; if (!objcProtos.empty()) { switch (mode) { case CheckedCastMode::Unconditional: break; case CheckedCastMode::Conditional: { origBB = IGF.Builder.GetInsertBlock(); successBB = IGF.createBasicBlock("success"); contBB = IGF.createBasicBlock("cont"); auto isNull = IGF.Builder.CreateICmpEQ(objcCast, llvm::ConstantPointerNull::get( cast<llvm::PointerType>(objcCast->getType()))); IGF.Builder.CreateCondBr(isNull, contBB, successBB); IGF.Builder.emitBlock(successBB); condition.emplace(IGF); } } } // Get the Swift type metadata for the type. llvm::Value *metadataValue; if (metatypeKind) { switch (*metatypeKind) { case MetatypeRepresentation::Thin: llvm_unreachable("can't cast to thin metatype"); case MetatypeRepresentation::Thick: // The value is already a native metatype. metadataValue = value; break; case MetatypeRepresentation::ObjC: // Get the type metadata from the ObjC class, which may be a wrapper. metadataValue = emitObjCMetadataRefForMetadata(IGF, value); } } else { // Get the type metadata for the instance. metadataValue = emitDynamicTypeOfHeapObject(IGF, value, srcType); } // Look up witness tables for the protocols that need them. auto fn = emitExistentialScalarCastFn(IGF.IGM, witnessTableProtos.size(), mode, checkClassConstraint, checkSuperclassConstraint); llvm::SmallVector<llvm::Value *, 4> args; if (resultValue->getType() != IGF.IGM.Int8PtrTy) resultValue = IGF.Builder.CreateBitCast(resultValue, IGF.IGM.Int8PtrTy); args.push_back(resultValue); args.push_back(metadataValue); if (checkSuperclassConstraint) args.push_back(IGF.emitTypeMetadataRef(CanType(layout.superclass))); for (auto proto : witnessTableProtos) args.push_back(proto); auto valueAndWitnessTables = IGF.Builder.CreateCall(fn, args); resultValue = IGF.Builder.CreateExtractValue(valueAndWitnessTables, 0); if (resultValue->getType() != resultType) resultValue = IGF.Builder.CreateBitCast(resultValue, resultType); ex.add(resultValue); for (unsigned i = 0, e = witnessTableProtos.size(); i < e; ++i) { auto wt = IGF.Builder.CreateExtractValue(valueAndWitnessTables, i + 1); ex.add(wt); } // If we had conditional ObjC checks, join the failure paths. if (contBB) { condition.reset(); IGF.Builder.CreateBr(contBB); IGF.Builder.emitBlock(contBB); // Return null on the failure path. Explosion successEx = std::move(ex); ex.reset(); while (!successEx.empty()) { auto successVal = successEx.claimNext(); auto failureVal = llvm::Constant::getNullValue(successVal->getType()); auto phi = IGF.Builder.CreatePHI(successVal->getType(), 2); phi->addIncoming(successVal, successBB); phi->addIncoming(failureVal, origBB); ex.add(phi); } } }
/// emitBuiltinCall - Emit a call to a builtin function. void irgen::emitBuiltinCall(IRGenFunction &IGF, Identifier FnId, SILType resultType, Explosion &args, Explosion &out, SubstitutionList substitutions) { // Decompose the function's name into a builtin name and type list. const BuiltinInfo &Builtin = IGF.getSILModule().getBuiltinInfo(FnId); if (Builtin.ID == BuiltinValueKind::UnsafeGuaranteedEnd) { // Just consume the incoming argument. assert(args.size() == 1 && "Expecting one incoming argument"); (void)args.claimAll(); return; } if (Builtin.ID == BuiltinValueKind::UnsafeGuaranteed) { // Just forward the incoming argument. assert(args.size() == 1 && "Expecting one incoming argument"); out = std::move(args); // This is a token. out.add(llvm::ConstantInt::get(IGF.IGM.Int8Ty, 0)); return; } if (Builtin.ID == BuiltinValueKind::OnFastPath) { // The onFastPath builtin has only an effect on SIL level, so we lower it // to a no-op. return; } // These builtins don't care about their argument: if (Builtin.ID == BuiltinValueKind::Sizeof) { (void)args.claimAll(); auto valueTy = getLoweredTypeAndTypeInfo(IGF.IGM, substitutions[0].getReplacement()); out.add(valueTy.second.getSize(IGF, valueTy.first)); return; } if (Builtin.ID == BuiltinValueKind::Strideof) { (void)args.claimAll(); auto valueTy = getLoweredTypeAndTypeInfo(IGF.IGM, substitutions[0].getReplacement()); out.add(valueTy.second.getStride(IGF, valueTy.first)); return; } if (Builtin.ID == BuiltinValueKind::Alignof) { (void)args.claimAll(); auto valueTy = getLoweredTypeAndTypeInfo(IGF.IGM, substitutions[0].getReplacement()); // The alignof value is one greater than the alignment mask. out.add(IGF.Builder.CreateAdd( valueTy.second.getAlignmentMask(IGF, valueTy.first), IGF.IGM.getSize(Size(1)))); return; } if (Builtin.ID == BuiltinValueKind::IsPOD) { (void)args.claimAll(); auto valueTy = getLoweredTypeAndTypeInfo(IGF.IGM, substitutions[0].getReplacement()); out.add(valueTy.second.getIsPOD(IGF, valueTy.first)); return; } // addressof expects an lvalue argument. if (Builtin.ID == BuiltinValueKind::AddressOf) { llvm::Value *address = args.claimNext(); llvm::Value *value = IGF.Builder.CreateBitCast(address, IGF.IGM.Int8PtrTy); out.add(value); return; } // Everything else cares about the (rvalue) argument. // If this is an LLVM IR intrinsic, lower it to an intrinsic call. const IntrinsicInfo &IInfo = IGF.getSILModule().getIntrinsicInfo(FnId); llvm::Intrinsic::ID IID = IInfo.ID; // Calls to the int_instrprof_increment intrinsic are emitted during SILGen. // At that stage, the function name GV used by the profiling pass is hidden. // Fix the intrinsic call here by pointing it to the correct GV. if (IID == llvm::Intrinsic::instrprof_increment) { // Extract the PGO function name. auto *NameGEP = cast<llvm::User>(args.claimNext()); auto *NameGV = dyn_cast<llvm::GlobalVariable>(NameGEP->stripPointerCasts()); if (NameGV) { auto *NameC = NameGV->getInitializer(); StringRef Name = cast<llvm::ConstantDataArray>(NameC)->getRawDataValues(); StringRef PGOFuncName = Name.rtrim(StringRef("\0", 1)); // Point the increment call to the right function name variable. std::string PGOFuncNameVar = llvm::getPGOFuncNameVarName( PGOFuncName, llvm::GlobalValue::LinkOnceAnyLinkage); auto *FuncNamePtr = IGF.IGM.Module.getNamedGlobal(PGOFuncNameVar); if (FuncNamePtr) { llvm::SmallVector<llvm::Value *, 2> Indices(2, NameGEP->getOperand(1)); NameGEP = llvm::ConstantExpr::getGetElementPtr( ((llvm::PointerType *)FuncNamePtr->getType())->getElementType(), FuncNamePtr, makeArrayRef(Indices)); } } // Replace the placeholder value with the new GEP. Explosion replacement; replacement.add(NameGEP); replacement.add(args.claimAll()); args = std::move(replacement); } if (IID != llvm::Intrinsic::not_intrinsic) { SmallVector<llvm::Type*, 4> ArgTys; for (auto T : IInfo.Types) ArgTys.push_back(IGF.IGM.getStorageTypeForLowered(T->getCanonicalType())); auto F = llvm::Intrinsic::getDeclaration(&IGF.IGM.Module, (llvm::Intrinsic::ID)IID, ArgTys); llvm::FunctionType *FT = F->getFunctionType(); SmallVector<llvm::Value*, 8> IRArgs; for (unsigned i = 0, e = FT->getNumParams(); i != e; ++i) IRArgs.push_back(args.claimNext()); llvm::Value *TheCall = IGF.Builder.CreateCall(F, IRArgs); if (!TheCall->getType()->isVoidTy()) extractScalarResults(IGF, TheCall->getType(), TheCall, out); return; } // TODO: A linear series of ifs is suboptimal. #define BUILTIN_SIL_OPERATION(id, name, overload) \ if (Builtin.ID == BuiltinValueKind::id) \ llvm_unreachable(name " builtin should be lowered away by SILGen!"); #define BUILTIN_CAST_OPERATION(id, name, attrs) \ if (Builtin.ID == BuiltinValueKind::id) \ return emitCastBuiltin(IGF, resultType, out, args, \ llvm::Instruction::id); #define BUILTIN_CAST_OR_BITCAST_OPERATION(id, name, attrs) \ if (Builtin.ID == BuiltinValueKind::id) \ return emitCastOrBitCastBuiltin(IGF, resultType, out, args, \ BuiltinValueKind::id); #define BUILTIN_BINARY_OPERATION(id, name, attrs, overload) \ if (Builtin.ID == BuiltinValueKind::id) { \ llvm::Value *lhs = args.claimNext(); \ llvm::Value *rhs = args.claimNext(); \ llvm::Value *v = IGF.Builder.Create##id(lhs, rhs); \ return out.add(v); \ } #define BUILTIN_RUNTIME_CALL(id, name, attrs) \ if (Builtin.ID == BuiltinValueKind::id) { \ llvm::CallInst *call = IGF.Builder.CreateCall(IGF.IGM.get##id##Fn(), \ args.claimNext()); \ call->setCallingConv(IGF.IGM.DefaultCC); \ call->setDoesNotThrow(); \ return out.add(call); \ } #define BUILTIN_BINARY_OPERATION_WITH_OVERFLOW(id, name, uncheckedID, attrs, overload) \ if (Builtin.ID == BuiltinValueKind::id) { \ SmallVector<llvm::Type*, 2> ArgTys; \ auto opType = Builtin.Types[0]->getCanonicalType(); \ ArgTys.push_back(IGF.IGM.getStorageTypeForLowered(opType)); \ auto F = llvm::Intrinsic::getDeclaration(&IGF.IGM.Module, \ getLLVMIntrinsicIDForBuiltinWithOverflow(Builtin.ID), ArgTys); \ SmallVector<llvm::Value*, 2> IRArgs; \ IRArgs.push_back(args.claimNext()); \ IRArgs.push_back(args.claimNext()); \ args.claimNext();\ llvm::Value *TheCall = IGF.Builder.CreateCall(F, IRArgs); \ extractScalarResults(IGF, TheCall->getType(), TheCall, out); \ return; \ } // FIXME: We could generate the code to dynamically report the overflow if the // third argument is true. Now, we just ignore it. #define BUILTIN_BINARY_PREDICATE(id, name, attrs, overload) \ if (Builtin.ID == BuiltinValueKind::id) \ return emitCompareBuiltin(IGF, out, args, llvm::CmpInst::id); #define BUILTIN_TYPE_TRAIT_OPERATION(id, name) \ if (Builtin.ID == BuiltinValueKind::id) \ return emitTypeTraitBuiltin(IGF, out, args, substitutions, &TypeBase::name); #define BUILTIN(ID, Name, Attrs) // Ignore the rest. #include "swift/AST/Builtins.def" if (Builtin.ID == BuiltinValueKind::FNeg) { llvm::Value *rhs = args.claimNext(); llvm::Value *lhs = llvm::ConstantFP::get(rhs->getType(), "-0.0"); llvm::Value *v = IGF.Builder.CreateFSub(lhs, rhs); return out.add(v); } if (Builtin.ID == BuiltinValueKind::AssumeNonNegative) { llvm::Value *v = args.claimNext(); // Set a value range on the load instruction, which must be the argument of // the builtin. if (isa<llvm::LoadInst>(v) || isa<llvm::CallInst>(v)) { // The load must be post-dominated by the builtin. Otherwise we would get // a wrong assumption in the else-branch in this example: // x = f() // if condition { // y = assumeNonNegative(x) // } else { // // x might be negative here! // } // For simplicity we just enforce that both the load and the builtin must // be in the same block. llvm::Instruction *I = static_cast<llvm::Instruction *>(v); if (I->getParent() == IGF.Builder.GetInsertBlock()) { llvm::LLVMContext &ctx = IGF.IGM.Module.getContext(); auto *intType = dyn_cast<llvm::IntegerType>(v->getType()); llvm::Metadata *rangeElems[] = { llvm::ConstantAsMetadata::get(llvm::ConstantInt::get(intType, 0)), llvm::ConstantAsMetadata::get( llvm::ConstantInt::get(intType, APInt::getSignedMaxValue(intType->getBitWidth()))) }; llvm::MDNode *range = llvm::MDNode::get(ctx, rangeElems); I->setMetadata(llvm::LLVMContext::MD_range, range); } } // Don't generate any code for the builtin. return out.add(v); } if (Builtin.ID == BuiltinValueKind::AllocRaw) { auto size = args.claimNext(); auto align = args.claimNext(); // Translate the alignment to a mask. auto alignMask = IGF.Builder.CreateSub(align, IGF.IGM.getSize(Size(1))); auto alloc = IGF.emitAllocRawCall(size, alignMask, "builtin-allocRaw"); out.add(alloc); return; } if (Builtin.ID == BuiltinValueKind::DeallocRaw) { auto pointer = args.claimNext(); auto size = args.claimNext(); auto align = args.claimNext(); // Translate the alignment to a mask. auto alignMask = IGF.Builder.CreateSub(align, IGF.IGM.getSize(Size(1))); IGF.emitDeallocRawCall(pointer, size, alignMask); return; } if (Builtin.ID == BuiltinValueKind::Fence) { SmallVector<Type, 4> Types; StringRef BuiltinName = getBuiltinBaseName(IGF.IGM.Context, FnId.str(), Types); BuiltinName = BuiltinName.drop_front(strlen("fence_")); // Decode the ordering argument, which is required. auto underscore = BuiltinName.find('_'); auto ordering = decodeLLVMAtomicOrdering(BuiltinName.substr(0, underscore)); assert(ordering != llvm::AtomicOrdering::NotAtomic); BuiltinName = BuiltinName.substr(underscore); // Accept singlethread if present. bool isSingleThread = BuiltinName.startswith("_singlethread"); if (isSingleThread) BuiltinName = BuiltinName.drop_front(strlen("_singlethread")); assert(BuiltinName.empty() && "Mismatch with sema"); IGF.Builder.CreateFence(ordering, isSingleThread ? llvm::SyncScope::SingleThread : llvm::SyncScope::System); return; } if (Builtin.ID == BuiltinValueKind::CmpXChg) { SmallVector<Type, 4> Types; StringRef BuiltinName = getBuiltinBaseName(IGF.IGM.Context, FnId.str(), Types); BuiltinName = BuiltinName.drop_front(strlen("cmpxchg_")); // Decode the success- and failure-ordering arguments, which are required. SmallVector<StringRef, 4> Parts; BuiltinName.split(Parts, "_"); assert(Parts.size() >= 2 && "Mismatch with sema"); auto successOrdering = decodeLLVMAtomicOrdering(Parts[0]); auto failureOrdering = decodeLLVMAtomicOrdering(Parts[1]); assert(successOrdering != llvm::AtomicOrdering::NotAtomic); assert(failureOrdering != llvm::AtomicOrdering::NotAtomic); auto NextPart = Parts.begin() + 2; // Accept weak, volatile, and singlethread if present. bool isWeak = false, isVolatile = false, isSingleThread = false; if (NextPart != Parts.end() && *NextPart == "weak") { isWeak = true; NextPart++; } if (NextPart != Parts.end() && *NextPart == "volatile") { isVolatile = true; NextPart++; } if (NextPart != Parts.end() && *NextPart == "singlethread") { isSingleThread = true; NextPart++; } assert(NextPart == Parts.end() && "Mismatch with sema"); auto pointer = args.claimNext(); auto cmp = args.claimNext(); auto newval = args.claimNext(); llvm::Type *origTy = cmp->getType(); if (origTy->isPointerTy()) { cmp = IGF.Builder.CreatePtrToInt(cmp, IGF.IGM.IntPtrTy); newval = IGF.Builder.CreatePtrToInt(newval, IGF.IGM.IntPtrTy); } pointer = IGF.Builder.CreateBitCast(pointer, llvm::PointerType::getUnqual(cmp->getType())); llvm::Value *value = IGF.Builder.CreateAtomicCmpXchg( pointer, cmp, newval, successOrdering, failureOrdering, isSingleThread ? llvm::SyncScope::SingleThread : llvm::SyncScope::System); cast<llvm::AtomicCmpXchgInst>(value)->setVolatile(isVolatile); cast<llvm::AtomicCmpXchgInst>(value)->setWeak(isWeak); auto valueLoaded = IGF.Builder.CreateExtractValue(value, {0}); auto loadSuccessful = IGF.Builder.CreateExtractValue(value, {1}); if (origTy->isPointerTy()) valueLoaded = IGF.Builder.CreateIntToPtr(valueLoaded, origTy); out.add(valueLoaded); out.add(loadSuccessful); return; } if (Builtin.ID == BuiltinValueKind::AtomicRMW) { using namespace llvm; SmallVector<Type, 4> Types; StringRef BuiltinName = getBuiltinBaseName(IGF.IGM.Context, FnId.str(), Types); BuiltinName = BuiltinName.drop_front(strlen("atomicrmw_")); auto underscore = BuiltinName.find('_'); StringRef SubOp = BuiltinName.substr(0, underscore); AtomicRMWInst::BinOp SubOpcode = StringSwitch<AtomicRMWInst::BinOp>(SubOp) .Case("xchg", AtomicRMWInst::Xchg) .Case("add", AtomicRMWInst::Add) .Case("sub", AtomicRMWInst::Sub) .Case("and", AtomicRMWInst::And) .Case("nand", AtomicRMWInst::Nand) .Case("or", AtomicRMWInst::Or) .Case("xor", AtomicRMWInst::Xor) .Case("max", AtomicRMWInst::Max) .Case("min", AtomicRMWInst::Min) .Case("umax", AtomicRMWInst::UMax) .Case("umin", AtomicRMWInst::UMin); BuiltinName = BuiltinName.drop_front(underscore+1); // Decode the ordering argument, which is required. underscore = BuiltinName.find('_'); auto ordering = decodeLLVMAtomicOrdering(BuiltinName.substr(0, underscore)); assert(ordering != llvm::AtomicOrdering::NotAtomic); BuiltinName = BuiltinName.substr(underscore); // Accept volatile and singlethread if present. bool isVolatile = BuiltinName.startswith("_volatile"); if (isVolatile) BuiltinName = BuiltinName.drop_front(strlen("_volatile")); bool isSingleThread = BuiltinName.startswith("_singlethread"); if (isSingleThread) BuiltinName = BuiltinName.drop_front(strlen("_singlethread")); assert(BuiltinName.empty() && "Mismatch with sema"); auto pointer = args.claimNext(); auto val = args.claimNext(); // Handle atomic ops on pointers by casting to intptr_t. llvm::Type *origTy = val->getType(); if (origTy->isPointerTy()) val = IGF.Builder.CreatePtrToInt(val, IGF.IGM.IntPtrTy); pointer = IGF.Builder.CreateBitCast(pointer, llvm::PointerType::getUnqual(val->getType())); llvm::Value *value = IGF.Builder.CreateAtomicRMW( SubOpcode, pointer, val, ordering, isSingleThread ? llvm::SyncScope::SingleThread : llvm::SyncScope::System); cast<AtomicRMWInst>(value)->setVolatile(isVolatile); if (origTy->isPointerTy()) value = IGF.Builder.CreateIntToPtr(value, origTy); out.add(value); return; } if (Builtin.ID == BuiltinValueKind::AtomicLoad || Builtin.ID == BuiltinValueKind::AtomicStore) { using namespace llvm; SmallVector<Type, 4> Types; StringRef BuiltinName = getBuiltinBaseName(IGF.IGM.Context, FnId.str(), Types); auto underscore = BuiltinName.find('_'); BuiltinName = BuiltinName.substr(underscore+1); underscore = BuiltinName.find('_'); auto ordering = decodeLLVMAtomicOrdering(BuiltinName.substr(0, underscore)); assert(ordering != llvm::AtomicOrdering::NotAtomic); BuiltinName = BuiltinName.substr(underscore); // Accept volatile and singlethread if present. bool isVolatile = BuiltinName.startswith("_volatile"); if (isVolatile) BuiltinName = BuiltinName.drop_front(strlen("_volatile")); bool isSingleThread = BuiltinName.startswith("_singlethread"); if (isSingleThread) BuiltinName = BuiltinName.drop_front(strlen("_singlethread")); assert(BuiltinName.empty() && "Mismatch with sema"); auto pointer = args.claimNext(); auto &valueTI = IGF.getTypeInfoForUnlowered(Types[0]); auto schema = valueTI.getSchema(); assert(schema.size() == 1 && "not a scalar type?!"); auto origValueTy = schema[0].getScalarType(); // If the type is floating-point, then we need to bitcast to integer. auto valueTy = origValueTy; if (valueTy->isFloatingPointTy()) { valueTy = llvm::IntegerType::get(IGF.IGM.LLVMContext, valueTy->getPrimitiveSizeInBits()); } pointer = IGF.Builder.CreateBitCast(pointer, valueTy->getPointerTo()); if (Builtin.ID == BuiltinValueKind::AtomicLoad) { auto load = IGF.Builder.CreateLoad(pointer, valueTI.getBestKnownAlignment()); load->setAtomic(ordering, isSingleThread ? llvm::SyncScope::SingleThread : llvm::SyncScope::System); load->setVolatile(isVolatile); llvm::Value *value = load; if (valueTy != origValueTy) value = IGF.Builder.CreateBitCast(value, origValueTy); out.add(value); return; } else if (Builtin.ID == BuiltinValueKind::AtomicStore) { llvm::Value *value = args.claimNext(); if (valueTy != origValueTy) value = IGF.Builder.CreateBitCast(value, valueTy); auto store = IGF.Builder.CreateStore(value, pointer, valueTI.getBestKnownAlignment()); store->setAtomic(ordering, isSingleThread ? llvm::SyncScope::SingleThread : llvm::SyncScope::System); store->setVolatile(isVolatile); return; } else { llvm_unreachable("out of sync with outer conditional"); } } if (Builtin.ID == BuiltinValueKind::ExtractElement) { using namespace llvm; auto vector = args.claimNext(); auto index = args.claimNext(); out.add(IGF.Builder.CreateExtractElement(vector, index)); return; } if (Builtin.ID == BuiltinValueKind::InsertElement) { using namespace llvm; auto vector = args.claimNext(); auto newValue = args.claimNext(); auto index = args.claimNext(); out.add(IGF.Builder.CreateInsertElement(vector, newValue, index)); return; } if (Builtin.ID == BuiltinValueKind::SToSCheckedTrunc || Builtin.ID == BuiltinValueKind::UToUCheckedTrunc || Builtin.ID == BuiltinValueKind::SToUCheckedTrunc) { auto FromTy = IGF.IGM.getStorageTypeForLowered(Builtin.Types[0]->getCanonicalType()); auto ToTy = IGF.IGM.getStorageTypeForLowered(Builtin.Types[1]->getCanonicalType()); // Compute the result for SToSCheckedTrunc_IntFrom_IntTo(Arg): // Res = trunc_IntTo(Arg) // Ext = sext_IntFrom(Res) // OverflowFlag = (Arg == Ext) ? 0 : 1 // return (resultVal, OverflowFlag) // // Compute the result for UToUCheckedTrunc_IntFrom_IntTo(Arg) // and SToUCheckedTrunc_IntFrom_IntTo(Arg): // Res = trunc_IntTo(Arg) // Ext = zext_IntFrom(Res) // OverflowFlag = (Arg == Ext) ? 0 : 1 // return (Res, OverflowFlag) llvm::Value *Arg = args.claimNext(); llvm::Value *Res = IGF.Builder.CreateTrunc(Arg, ToTy); bool Signed = (Builtin.ID == BuiltinValueKind::SToSCheckedTrunc); llvm::Value *Ext = Signed ? IGF.Builder.CreateSExt(Res, FromTy) : IGF.Builder.CreateZExt(Res, FromTy); llvm::Value *OverflowCond = IGF.Builder.CreateICmpEQ(Arg, Ext); llvm::Value *OverflowFlag = IGF.Builder.CreateSelect(OverflowCond, llvm::ConstantInt::get(IGF.IGM.Int1Ty, 0), llvm::ConstantInt::get(IGF.IGM.Int1Ty, 1)); // Return the tuple - the result + the overflow flag. out.add(Res); return out.add(OverflowFlag); } if (Builtin.ID == BuiltinValueKind::UToSCheckedTrunc) { auto FromTy = IGF.IGM.getStorageTypeForLowered(Builtin.Types[0]->getCanonicalType()); auto ToTy = IGF.IGM.getStorageTypeForLowered(Builtin.Types[1]->getCanonicalType()); llvm::Type *ToMinusOneTy = llvm::Type::getIntNTy(ToTy->getContext(), ToTy->getIntegerBitWidth() - 1); // Compute the result for UToSCheckedTrunc_IntFrom_IntTo(Arg): // Res = trunc_IntTo(Arg) // Trunc = trunc_'IntTo-1bit'(Arg) // Ext = zext_IntFrom(Trunc) // OverflowFlag = (Arg == Ext) ? 0 : 1 // return (Res, OverflowFlag) llvm::Value *Arg = args.claimNext(); llvm::Value *Res = IGF.Builder.CreateTrunc(Arg, ToTy); llvm::Value *Trunc = IGF.Builder.CreateTrunc(Arg, ToMinusOneTy); llvm::Value *Ext = IGF.Builder.CreateZExt(Trunc, FromTy); llvm::Value *OverflowCond = IGF.Builder.CreateICmpEQ(Arg, Ext); llvm::Value *OverflowFlag = IGF.Builder.CreateSelect(OverflowCond, llvm::ConstantInt::get(IGF.IGM.Int1Ty, 0), llvm::ConstantInt::get(IGF.IGM.Int1Ty, 1)); // Return the tuple: (the result, the overflow flag). out.add(Res); return out.add(OverflowFlag); } if (Builtin.ID == BuiltinValueKind::SUCheckedConversion || Builtin.ID == BuiltinValueKind::USCheckedConversion) { auto Ty = IGF.IGM.getStorageTypeForLowered(Builtin.Types[0]->getCanonicalType()); // Report a sign error if the input parameter is a negative number, when // interpreted as signed. llvm::Value *Arg = args.claimNext(); llvm::Value *Zero = llvm::ConstantInt::get(Ty, 0); llvm::Value *OverflowFlag = IGF.Builder.CreateICmpSLT(Arg, Zero); // Return the tuple: (the result (same as input), the overflow flag). out.add(Arg); return out.add(OverflowFlag); } // We are currently emitting code for '_convertFromBuiltinIntegerLiteral', // which will call the builtin and pass it a non-compile-time-const parameter. if (Builtin.ID == BuiltinValueKind::IntToFPWithOverflow) { auto ToTy = IGF.IGM.getStorageTypeForLowered(Builtin.Types[1]->getCanonicalType()); llvm::Value *Arg = args.claimNext(); unsigned bitSize = Arg->getType()->getScalarSizeInBits(); if (bitSize > 64) { // TODO: the integer literal bit size is 2048, but we only have a 64-bit // conversion function available (on all platforms). Arg = IGF.Builder.CreateTrunc(Arg, IGF.IGM.Int64Ty); } else if (bitSize < 64) { // Just for completeness. IntToFPWithOverflow is currently only used to // convert 2048 bit integer literals. Arg = IGF.Builder.CreateSExt(Arg, IGF.IGM.Int64Ty); } llvm::Value *V = IGF.Builder.CreateSIToFP(Arg, ToTy); return out.add(V); } if (Builtin.ID == BuiltinValueKind::Once || Builtin.ID == BuiltinValueKind::OnceWithContext) { // The input type is statically (Builtin.RawPointer, @convention(thin) () -> ()). llvm::Value *PredPtr = args.claimNext(); // Cast the predicate to a OnceTy pointer. PredPtr = IGF.Builder.CreateBitCast(PredPtr, IGF.IGM.OnceTy->getPointerTo()); llvm::Value *FnCode = args.claimNext(); // Get the context if any. llvm::Value *Context; if (Builtin.ID == BuiltinValueKind::OnceWithContext) { Context = args.claimNext(); } else { Context = llvm::UndefValue::get(IGF.IGM.Int8PtrTy); } // If we know the platform runtime's "done" value, emit the check inline. llvm::BasicBlock *doneBB = nullptr; if (auto ExpectedPred = IGF.IGM.TargetInfo.OnceDonePredicateValue) { auto PredValue = IGF.Builder.CreateLoad(PredPtr, IGF.IGM.getPointerAlignment()); auto ExpectedPredValue = llvm::ConstantInt::getSigned(IGF.IGM.OnceTy, *ExpectedPred); auto PredIsDone = IGF.Builder.CreateICmpEQ(PredValue, ExpectedPredValue); auto notDoneBB = IGF.createBasicBlock("once_not_done"); doneBB = IGF.createBasicBlock("once_done"); IGF.Builder.CreateCondBr(PredIsDone, doneBB, notDoneBB); IGF.Builder.emitBlock(notDoneBB); } // Emit the runtime "once" call. auto call = IGF.Builder.CreateCall(IGF.IGM.getOnceFn(), {PredPtr, FnCode, Context}); call->setCallingConv(IGF.IGM.DefaultCC); // If we emitted the "done" check inline, join the branches. if (auto ExpectedPred = IGF.IGM.TargetInfo.OnceDonePredicateValue) { IGF.Builder.CreateBr(doneBB); IGF.Builder.emitBlock(doneBB); // We can assume the once predicate is in the "done" state now. auto PredValue = IGF.Builder.CreateLoad(PredPtr, IGF.IGM.getPointerAlignment()); auto ExpectedPredValue = llvm::ConstantInt::getSigned(IGF.IGM.OnceTy, *ExpectedPred); auto PredIsDone = IGF.Builder.CreateICmpEQ(PredValue, ExpectedPredValue); IGF.Builder.CreateAssumption(PredIsDone); } // No return value. return; } if (Builtin.ID == BuiltinValueKind::AssertConf) { // Replace the call to assert_configuration by the Debug configuration // value. // TODO: assert(IGF.IGM.getOptions().AssertConfig == // SILOptions::DisableReplacement); // Make sure this only happens in a mode where we build a library dylib. llvm::Value *DebugAssert = IGF.Builder.getInt32(SILOptions::Debug); out.add(DebugAssert); return; } if (Builtin.ID == BuiltinValueKind::DestroyArray) { // The input type is (T.Type, Builtin.RawPointer, Builtin.Word). /* metatype (which may be thin) */ if (args.size() == 3) args.claimNext(); llvm::Value *ptr = args.claimNext(); llvm::Value *count = args.claimNext(); auto valueTy = getLoweredTypeAndTypeInfo(IGF.IGM, substitutions[0].getReplacement()); ptr = IGF.Builder.CreateBitCast(ptr, valueTy.second.getStorageType()->getPointerTo()); Address array = valueTy.second.getAddressForPointer(ptr); valueTy.second.destroyArray(IGF, array, count, valueTy.first); return; } if (Builtin.ID == BuiltinValueKind::CopyArray || Builtin.ID == BuiltinValueKind::TakeArrayNoAlias || Builtin.ID == BuiltinValueKind::TakeArrayFrontToBack || Builtin.ID == BuiltinValueKind::TakeArrayBackToFront || Builtin.ID == BuiltinValueKind::AssignCopyArrayNoAlias || Builtin.ID == BuiltinValueKind::AssignCopyArrayFrontToBack || Builtin.ID == BuiltinValueKind::AssignCopyArrayBackToFront || Builtin.ID == BuiltinValueKind::AssignTakeArray) { // The input type is (T.Type, Builtin.RawPointer, Builtin.RawPointer, Builtin.Word). /* metatype (which may be thin) */ if (args.size() == 4) args.claimNext(); llvm::Value *dest = args.claimNext(); llvm::Value *src = args.claimNext(); llvm::Value *count = args.claimNext(); auto valueTy = getLoweredTypeAndTypeInfo(IGF.IGM, substitutions[0].getReplacement()); dest = IGF.Builder.CreateBitCast(dest, valueTy.second.getStorageType()->getPointerTo()); src = IGF.Builder.CreateBitCast(src, valueTy.second.getStorageType()->getPointerTo()); Address destArray = valueTy.second.getAddressForPointer(dest); Address srcArray = valueTy.second.getAddressForPointer(src); switch (Builtin.ID) { case BuiltinValueKind::CopyArray: valueTy.second.initializeArrayWithCopy(IGF, destArray, srcArray, count, valueTy.first); break; case BuiltinValueKind::TakeArrayNoAlias: valueTy.second.initializeArrayWithTakeNoAlias(IGF, destArray, srcArray, count, valueTy.first); break; case BuiltinValueKind::TakeArrayFrontToBack: valueTy.second.initializeArrayWithTakeFrontToBack(IGF, destArray, srcArray, count, valueTy.first); break; case BuiltinValueKind::TakeArrayBackToFront: valueTy.second.initializeArrayWithTakeBackToFront(IGF, destArray, srcArray, count, valueTy.first); break; case BuiltinValueKind::AssignCopyArrayNoAlias: valueTy.second.assignArrayWithCopyNoAlias(IGF, destArray, srcArray, count, valueTy.first); break; case BuiltinValueKind::AssignCopyArrayFrontToBack: valueTy.second.assignArrayWithCopyFrontToBack(IGF, destArray, srcArray, count, valueTy.first); break; case BuiltinValueKind::AssignCopyArrayBackToFront: valueTy.second.assignArrayWithCopyBackToFront(IGF, destArray, srcArray, count, valueTy.first); break; case BuiltinValueKind::AssignTakeArray: valueTy.second.assignArrayWithTake(IGF, destArray, srcArray, count, valueTy.first); break; default: llvm_unreachable("out of sync with if condition"); } return; } if (Builtin.ID == BuiltinValueKind::CondUnreachable) { // conditionallyUnreachable is a no-op by itself. Since it's noreturn, there // should be a true unreachable terminator right after. return; } if (Builtin.ID == BuiltinValueKind::ZeroInitializer) { // Build a zero initializer of the result type. auto valueTy = getLoweredTypeAndTypeInfo(IGF.IGM, substitutions[0].getReplacement()); auto schema = valueTy.second.getSchema(); for (auto &elt : schema) { out.add(llvm::Constant::getNullValue(elt.getScalarType())); } return; } if (Builtin.ID == BuiltinValueKind::GetObjCTypeEncoding) { (void)args.claimAll(); Type valueTy = substitutions[0].getReplacement(); // Get the type encoding for the associated clang type. auto clangTy = IGF.IGM.getClangType(valueTy->getCanonicalType()); std::string encoding; IGF.IGM.getClangASTContext().getObjCEncodingForType(clangTy, encoding); auto globalString = IGF.IGM.getAddrOfGlobalString(encoding); out.add(globalString); return; } if (Builtin.ID == BuiltinValueKind::TSanInoutAccess) { auto address = args.claimNext(); IGF.emitTSanInoutAccessCall(address); return; } if (Builtin.ID == BuiltinValueKind::Swift3ImplicitObjCEntrypoint) { llvm::Value *entrypointArgs[7]; auto argIter = IGF.CurFn->arg_begin(); // self entrypointArgs[0] = &*argIter++; if (entrypointArgs[0]->getType() != IGF.IGM.ObjCPtrTy) entrypointArgs[0] = IGF.Builder.CreateBitCast(entrypointArgs[0], IGF.IGM.ObjCPtrTy); // _cmd entrypointArgs[1] = &*argIter; if (entrypointArgs[1]->getType() != IGF.IGM.ObjCSELTy) entrypointArgs[1] = IGF.Builder.CreateBitCast(entrypointArgs[1], IGF.IGM.ObjCSELTy); // Filename pointer entrypointArgs[2] = args.claimNext(); // Filename length entrypointArgs[3] = args.claimNext(); // Line entrypointArgs[4] = args.claimNext(); // Column entrypointArgs[5] = args.claimNext(); // Create a flag variable so that this invocation logs only once. auto flagStorageTy = llvm::ArrayType::get(IGF.IGM.Int8Ty, IGF.IGM.getAtomicBoolSize().getValue()); auto flag = new llvm::GlobalVariable(IGF.IGM.Module, flagStorageTy, /*constant*/ false, llvm::GlobalValue::PrivateLinkage, llvm::ConstantAggregateZero::get(flagStorageTy)); flag->setAlignment(IGF.IGM.getAtomicBoolAlignment().getValue()); entrypointArgs[6] = llvm::ConstantExpr::getBitCast(flag, IGF.IGM.Int8PtrTy); IGF.Builder.CreateCall(IGF.IGM.getSwift3ImplicitObjCEntrypointFn(), entrypointArgs); return; } if (Builtin.ID == BuiltinValueKind::IsSameMetatype) { auto metatypeLHS = args.claimNext(); auto metatypeRHS = args.claimNext(); (void)args.claimAll(); llvm::Value *metatypeLHSCasted = IGF.Builder.CreateBitCast(metatypeLHS, IGF.IGM.Int8PtrTy); llvm::Value *metatypeRHSCasted = IGF.Builder.CreateBitCast(metatypeRHS, IGF.IGM.Int8PtrTy); out.add(IGF.Builder.CreateICmpEQ(metatypeLHSCasted, metatypeRHSCasted)); return; } llvm_unreachable("IRGen unimplemented for this builtin!"); }