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b5f36f7bea
We were unnecessarily conservative here; generic metadata patterns support indirectable references to value witness tables exported by the standard library, so if we have a fixed-layout generic type that matches a known value witness table layout, use that instead of generating a new value witness table.
1374 lines
53 KiB
C++
1374 lines
53 KiB
C++
//===--- GenValueWitness.cpp - IR generation for value witnesses ----------===//
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//
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// This source file is part of the Swift.org open source project
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//
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// Copyright (c) 2014 - 2017 Apple Inc. and the Swift project authors
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// Licensed under Apache License v2.0 with Runtime Library Exception
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//
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// See https://swift.org/LICENSE.txt for license information
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// See https://swift.org/CONTRIBUTORS.txt for the list of Swift project authors
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//
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//===----------------------------------------------------------------------===//
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//
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// This file implements IR generation for value witnesses in Swift.
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//
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// Value witnesses are (predominantly) functions that implement the basic
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// operations for copying and destroying values.
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//
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// In the comments throughout this file, three type names are used:
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// 'B' is the type of a fixed-size buffer
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// 'T' is the type which implements a protocol
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//
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//===----------------------------------------------------------------------===//
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#include "swift/AST/ASTContext.h"
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#include "swift/AST/Types.h"
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#include "swift/IRGen/Linking.h"
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#include "swift/SIL/TypeLowering.h"
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#include "llvm/ADT/SmallString.h"
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#include "llvm/Support/raw_ostream.h"
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#include "llvm/IR/DerivedTypes.h"
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#include "llvm/IR/Function.h"
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#include "ConstantBuilder.h"
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#include "Explosion.h"
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#include "FixedTypeInfo.h"
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#include "GenEnum.h"
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#include "GenMeta.h"
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#include "GenOpaque.h"
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#include "IRGenDebugInfo.h"
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#include "IRGenFunction.h"
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#include "IRGenModule.h"
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#include "StructLayout.h"
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#include "TypeInfo.h"
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#include "GenValueWitness.h"
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using namespace swift;
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using namespace irgen;
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const char *irgen::getValueWitnessName(ValueWitness witness) {
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switch (witness) {
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#define CASE(NAME) case ValueWitness::NAME: return #NAME;
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CASE(AssignWithCopy)
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CASE(AssignWithTake)
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CASE(Destroy)
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CASE(InitializeBufferWithCopyOfBuffer)
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CASE(InitializeWithCopy)
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CASE(InitializeWithTake)
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CASE(GetEnumTag)
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CASE(DestructiveProjectEnumData)
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CASE(DestructiveInjectEnumTag)
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CASE(Size)
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CASE(Flags)
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CASE(ExtraInhabitantCount)
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CASE(Stride)
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CASE(GetEnumTagSinglePayload)
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CASE(StoreEnumTagSinglePayload)
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#undef CASE
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}
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llvm_unreachable("bad value witness kind");
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}
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namespace {
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/// An operation to be performed for various kinds of packing.
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struct DynamicPackingOperation {
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virtual ~DynamicPackingOperation() = default;
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/// Emit the operation at a concrete packing kind.
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///
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/// Immediately after this call, there will be an unconditional
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/// branch to the continuation block.
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virtual void emitForPacking(IRGenFunction &IGF,
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SILType T,
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const TypeInfo &type,
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FixedPacking packing) = 0;
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/// Given that we are currently at the beginning of the
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/// continuation block, complete the operation.
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virtual void complete(IRGenFunction &IGF) = 0;
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};
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/// A class for merging a particular kind of value across control flow.
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template <class T> class DynamicPackingPHIMapping;
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/// An implementation of DynamicPackingPHIMapping for a single LLVM value.
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template <> class DynamicPackingPHIMapping<llvm::Value*> {
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llvm::PHINode *PHI = nullptr;
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public:
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void collect(IRGenFunction &IGF, llvm::Value *value) {
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// Add the result to the phi, creating it (unparented) if necessary.
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if (!PHI) PHI = llvm::PHINode::Create(value->getType(), 2,
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"dynamic-packing.result");
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PHI->addIncoming(value, IGF.Builder.GetInsertBlock());
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}
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void complete(IRGenFunction &IGF) {
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assert(PHI);
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IGF.Builder.Insert(PHI);
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}
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llvm::Value *get(IRGenFunction &IGF, SILType T, const TypeInfo &type) {
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assert(PHI);
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return PHI;
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}
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};
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/// An implementation of DynamicPackingPHIMapping for Addresses.
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template <> class DynamicPackingPHIMapping<Address>
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: private DynamicPackingPHIMapping<llvm::Value*> {
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using super = DynamicPackingPHIMapping<llvm::Value *>;
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public:
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void collect(IRGenFunction &IGF, Address value) {
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super::collect(IGF, value.getAddress());
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}
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void complete(IRGenFunction &IGF) {
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super::complete(IGF);
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}
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Address get(IRGenFunction &IGF, SILType T, const TypeInfo &type) {
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return type.getAddressForPointer(super::get(IGF, T, type));
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}
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};
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/// An implementation of packing operations based around a lambda.
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template <class ResultTy, class FnTy>
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class LambdaDynamicPackingOperation : public DynamicPackingOperation {
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FnTy Fn;
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DynamicPackingPHIMapping<ResultTy> Mapping;
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public:
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explicit LambdaDynamicPackingOperation(FnTy &&fn) : Fn(fn) {}
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void emitForPacking(IRGenFunction &IGF, SILType T, const TypeInfo &type,
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FixedPacking packing) override {
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Mapping.collect(IGF, Fn(IGF, T, type, packing));
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}
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void complete(IRGenFunction &IGF) override {
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Mapping.complete(IGF);
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}
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ResultTy get(IRGenFunction &IGF, SILType T, const TypeInfo &type) {
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return Mapping.get(IGF, T, type);
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}
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};
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/// A partial specialization for lambda-based packing operations
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/// that return 'void'.
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template <class FnTy>
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class LambdaDynamicPackingOperation<void, FnTy>
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: public DynamicPackingOperation {
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FnTy Fn;
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public:
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explicit LambdaDynamicPackingOperation(FnTy &&fn) : Fn(fn) {}
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void emitForPacking(IRGenFunction &IGF, SILType T, const TypeInfo &type,
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FixedPacking packing) override {
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Fn(IGF, T, type, packing);
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}
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void complete(IRGenFunction &IGF) override {}
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void get(IRGenFunction &IGF, SILType T, const TypeInfo &type) {}
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};
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} // end anonymous namespace
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/// Dynamic check for the enabling conditions of different kinds of
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/// packing into a fixed-size buffer, and perform an operation at each
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/// of them.
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static void emitDynamicPackingOperation(IRGenFunction &IGF,
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SILType T,
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const TypeInfo &type,
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DynamicPackingOperation &operation) {
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auto indirectBB = IGF.createBasicBlock("dynamic-packing.indirect");
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auto directBB = IGF.createBasicBlock("dynamic-packing.direct");
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auto contBB = IGF.createBasicBlock("dynamic-packing.cont");
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// Branch.
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auto isInline = type.isDynamicallyPackedInline(IGF, T);
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IGF.Builder.CreateCondBr(isInline, directBB, indirectBB);
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// Emit the indirect path.
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IGF.Builder.emitBlock(indirectBB); {
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ConditionalDominanceScope condition(IGF);
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operation.emitForPacking(IGF, T, type, FixedPacking::Allocate);
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IGF.Builder.CreateBr(contBB);
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}
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// Emit the direct path.
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IGF.Builder.emitBlock(directBB); {
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ConditionalDominanceScope condition(IGF);
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operation.emitForPacking(IGF, T, type, FixedPacking::OffsetZero);
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IGF.Builder.CreateBr(contBB);
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}
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// Enter the continuation block and add the PHI if required.
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IGF.Builder.emitBlock(contBB);
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operation.complete(IGF);
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}
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/// A helper function for creating a lambda-based DynamicPackingOperation.
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template <class ResultTy, class FnTy>
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LambdaDynamicPackingOperation<ResultTy, FnTy>
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makeLambdaDynamicPackingOperation(FnTy &&fn) {
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return LambdaDynamicPackingOperation<ResultTy, FnTy>(std::move(fn));
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}
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/// Perform an operation on a type that requires dynamic packing.
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template <class ResultTy, class... ArgTys, class... ParamTys>
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static ResultTy emitForDynamicPacking(IRGenFunction &IGF,
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ResultTy (*fn)(ParamTys...),
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SILType T,
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const TypeInfo &type,
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ArgTys... args) {
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auto operation = makeLambdaDynamicPackingOperation<ResultTy>(
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[&](IRGenFunction &IGF, SILType T, const TypeInfo &type,
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FixedPacking packing) {
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return fn(IGF, args..., T, type, packing);
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});
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emitDynamicPackingOperation(IGF, T, type, operation);
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return operation.get(IGF, T, type);
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}
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/// Emit a 'projectBuffer' operation. Always returns a T*.
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static Address emitDefaultProjectBuffer(IRGenFunction &IGF, Address buffer,
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SILType T, const TypeInfo &type,
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FixedPacking packing) {
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llvm::PointerType *resultTy = type.getStorageType()->getPointerTo();
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switch (packing) {
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case FixedPacking::Allocate: {
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// Use copy-on-write existentials?
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auto &IGM = IGF.IGM;
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auto &Builder = IGF.Builder;
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Address boxAddress(
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Builder.CreateBitCast(buffer.getAddress(),
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IGM.RefCountedPtrTy->getPointerTo()),
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buffer.getAlignment());
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auto *boxStart = IGF.Builder.CreateLoad(boxAddress);
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auto *alignmentMask = type.getAlignmentMask(IGF, T);
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auto *heapHeaderSize = llvm::ConstantInt::get(
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IGM.SizeTy, IGM.RefCountedStructSize.getValue());
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auto *startOffset =
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Builder.CreateAnd(Builder.CreateAdd(heapHeaderSize, alignmentMask),
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Builder.CreateNot(alignmentMask));
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auto *addressInBox =
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IGF.emitByteOffsetGEP(boxStart, startOffset, IGM.OpaqueTy);
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addressInBox = Builder.CreateBitCast(addressInBox, resultTy);
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return type.getAddressForPointer(addressInBox);
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}
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case FixedPacking::OffsetZero: {
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return IGF.Builder.CreateBitCast(buffer, resultTy, "object");
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}
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case FixedPacking::Dynamic:
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return emitForDynamicPacking(IGF, &emitDefaultProjectBuffer,
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T, type, buffer);
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}
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llvm_unreachable("bad packing!");
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}
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/// Emit an 'allocateBuffer' operation. Always returns a T*.
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static Address emitDefaultAllocateBuffer(IRGenFunction &IGF, Address buffer,
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SILType T, const TypeInfo &type,
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FixedPacking packing) {
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switch (packing) {
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case FixedPacking::Allocate: {
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llvm::Value *box, *address;
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auto *metadata = IGF.emitTypeMetadataRefForLayout(T);
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IGF.emitAllocBoxCall(metadata, box, address);
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IGF.Builder.CreateStore(
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box, Address(IGF.Builder.CreateBitCast(buffer.getAddress(),
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box->getType()->getPointerTo()),
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buffer.getAlignment()));
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llvm::PointerType *resultTy = type.getStorageType()->getPointerTo();
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address = IGF.Builder.CreateBitCast(address, resultTy);
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return type.getAddressForPointer(address);
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}
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case FixedPacking::OffsetZero:
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return emitDefaultProjectBuffer(IGF, buffer, T, type, packing);
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case FixedPacking::Dynamic:
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return emitForDynamicPacking(IGF, &emitDefaultAllocateBuffer,
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T, type, buffer);
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}
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llvm_unreachable("bad packing!");
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}
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/// Emit an 'initializeBufferWithCopyOfBuffer' operation.
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/// Returns the address of the destination object.
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static Address emitDefaultInitializeBufferWithCopyOfBuffer(
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IRGenFunction &IGF, Address destBuffer, Address srcBuffer, SILType T,
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const TypeInfo &type, FixedPacking packing) {
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// Special-case dynamic packing in order to thread the jumps.
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if (packing == FixedPacking::Dynamic)
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return emitForDynamicPacking(IGF,
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&emitDefaultInitializeBufferWithCopyOfBuffer,
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T, type, destBuffer, srcBuffer);
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if (packing == FixedPacking::OffsetZero) {
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Address destObject =
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emitDefaultAllocateBuffer(IGF, destBuffer, T, type, packing);
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Address srcObject =
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emitDefaultProjectBuffer(IGF, srcBuffer, T, type, packing);
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type.initializeWithCopy(IGF, destObject, srcObject, T, true);
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return destObject;
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} else {
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assert(packing == FixedPacking::Allocate);
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auto *destReferenceAddr = IGF.Builder.CreateBitCast(
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destBuffer.getAddress(), IGF.IGM.RefCountedPtrTy->getPointerTo());
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auto *srcReferenceAddr = IGF.Builder.CreateBitCast(
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srcBuffer.getAddress(), IGF.IGM.RefCountedPtrTy->getPointerTo());
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auto *srcReference =
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IGF.Builder.CreateLoad(srcReferenceAddr, srcBuffer.getAlignment());
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IGF.emitNativeStrongRetain(srcReference, IGF.getDefaultAtomicity());
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IGF.Builder.CreateStore(
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srcReference, Address(destReferenceAddr, destBuffer.getAlignment()));
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return emitDefaultProjectBuffer(IGF, destBuffer, T, type, packing);
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}
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}
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// Metaprogram some of the common boilerplate here:
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// - the default implementation in TypeInfo
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// - the value-witness emitter which tries to avoid some dynamic
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// dispatch and the recomputation of the fixed packing
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#define DEFINE_BINARY_BUFFER_OP(LOWER, TITLE) \
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Address TypeInfo::LOWER(IRGenFunction &IGF, Address dest, Address src, \
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SILType T) const { \
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return emitDefault##TITLE(IGF, dest, src, T, *this, \
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getFixedPacking(IGF.IGM)); \
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} \
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static Address emit##TITLE(IRGenFunction &IGF, Address dest, Address src, \
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SILType T, const TypeInfo &type, \
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FixedPacking packing) { \
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if (packing == FixedPacking::Dynamic) \
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return type.LOWER(IGF, dest, src, T); \
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return emitDefault##TITLE(IGF, dest, src, T, type, packing); \
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}
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DEFINE_BINARY_BUFFER_OP(initializeBufferWithCopyOfBuffer,
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InitializeBufferWithCopyOfBuffer)
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#undef DEFINE_BINARY_BUFFER_OP
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static llvm::Value *getArg(llvm::Function::arg_iterator &it,
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StringRef name) {
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llvm::Value *arg = &*(it++);
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arg->setName(name);
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return arg;
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}
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/// Get the next argument as a pointer to the given storage type.
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static Address getArgAs(IRGenFunction &IGF,
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llvm::Function::arg_iterator &it,
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const TypeInfo &type,
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StringRef name) {
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llvm::Value *arg = getArg(it, name);
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llvm::Value *result =
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IGF.Builder.CreateBitCast(arg, type.getStorageType()->getPointerTo());
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return type.getAddressForPointer(result);
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}
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/// Get the next argument as a pointer to the given storage type.
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static Address getArgAsBuffer(IRGenFunction &IGF,
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llvm::Function::arg_iterator &it,
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StringRef name) {
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llvm::Value *arg = getArg(it, name);
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return Address(arg, getFixedBufferAlignment(IGF.IGM));
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}
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static CanType getFormalTypeInContext(CanType abstractType, DeclContext *dc) {
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// Map the parent of any non-generic nominal type.
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if (auto nominalType = dyn_cast<NominalType>(abstractType)) {
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// If it doesn't have a parent, or the parent doesn't need remapping,
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// do nothing.
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auto abstractParentType = nominalType.getParent();
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if (!abstractParentType) return abstractType;
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auto parentType = getFormalTypeInContext(abstractParentType, dc);
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if (abstractParentType == parentType) return abstractType;
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// Otherwise, rebuild the type.
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return CanType(NominalType::get(nominalType->getDecl(), parentType,
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nominalType->getDecl()->getASTContext()));
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// Map unbound types into their defining context.
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} else if (auto ugt = dyn_cast<UnboundGenericType>(abstractType)) {
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return dc->mapTypeIntoContext(ugt->getDecl()->getDeclaredInterfaceType())
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->getCanonicalType();
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// Everything else stays the same.
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} else {
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return abstractType;
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}
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}
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/// Given an abstract type --- a type possibly expressed in terms of
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/// unbound generic types --- return the formal type within the type's
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/// primary defining context.
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static CanType getFormalTypeInContext(CanType abstractType) {
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if (auto nominal = abstractType.getAnyNominal())
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return getFormalTypeInContext(abstractType, nominal);
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return abstractType;
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}
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void irgen::getArgAsLocalSelfTypeMetadata(IRGenFunction &IGF, llvm::Value *arg,
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CanType abstractType) {
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assert(arg->getType() == IGF.IGM.TypeMetadataPtrTy &&
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"Self argument is not a type?!");
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auto formalType = getFormalTypeInContext(abstractType);
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IGF.bindLocalTypeDataFromTypeMetadata(formalType, IsExact, arg,
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MetadataState::Complete);
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}
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/// Get the next argument and use it as the 'self' type metadata.
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static void getArgAsLocalSelfTypeMetadata(IRGenFunction &IGF,
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llvm::Function::arg_iterator &it,
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CanType abstractType) {
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llvm::Value *arg = &*it++;
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getArgAsLocalSelfTypeMetadata(IGF, arg, abstractType);
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}
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/// Build a specific value-witness function.
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static void buildValueWitnessFunction(IRGenModule &IGM,
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llvm::Function *fn,
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ValueWitness index,
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FixedPacking packing,
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CanType abstractType,
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SILType concreteType,
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const TypeInfo &type) {
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assert(isValueWitnessFunction(index));
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IRGenFunction IGF(IGM, fn);
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if (IGM.DebugInfo)
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IGM.DebugInfo->emitArtificialFunction(IGF, fn);
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auto argv = fn->arg_begin();
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switch (index) {
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case ValueWitness::AssignWithCopy: {
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Address dest = getArgAs(IGF, argv, type, "dest");
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Address src = getArgAs(IGF, argv, type, "src");
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getArgAsLocalSelfTypeMetadata(IGF, argv, abstractType);
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type.assignWithCopy(IGF, dest, src, concreteType, true);
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dest = IGF.Builder.CreateBitCast(dest, IGF.IGM.OpaquePtrTy);
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IGF.Builder.CreateRet(dest.getAddress());
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return;
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}
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case ValueWitness::AssignWithTake: {
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Address dest = getArgAs(IGF, argv, type, "dest");
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Address src = getArgAs(IGF, argv, type, "src");
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getArgAsLocalSelfTypeMetadata(IGF, argv, abstractType);
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type.assignWithTake(IGF, dest, src, concreteType, true);
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dest = IGF.Builder.CreateBitCast(dest, IGF.IGM.OpaquePtrTy);
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IGF.Builder.CreateRet(dest.getAddress());
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return;
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}
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case ValueWitness::Destroy: {
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Address object = getArgAs(IGF, argv, type, "object");
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getArgAsLocalSelfTypeMetadata(IGF, argv, abstractType);
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type.destroy(IGF, object, concreteType, true);
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IGF.Builder.CreateRetVoid();
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return;
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}
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case ValueWitness::InitializeBufferWithCopyOfBuffer: {
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Address dest = getArgAsBuffer(IGF, argv, "dest");
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Address src = getArgAsBuffer(IGF, argv, "src");
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getArgAsLocalSelfTypeMetadata(IGF, argv, abstractType);
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Address result =
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emitInitializeBufferWithCopyOfBuffer(IGF, dest, src, concreteType,
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type, packing);
|
|
result = IGF.Builder.CreateBitCast(result, IGF.IGM.OpaquePtrTy);
|
|
IGF.Builder.CreateRet(result.getAddress());
|
|
return;
|
|
}
|
|
|
|
case ValueWitness::InitializeWithCopy: {
|
|
Address dest = getArgAs(IGF, argv, type, "dest");
|
|
Address src = getArgAs(IGF, argv, type, "src");
|
|
getArgAsLocalSelfTypeMetadata(IGF, argv, abstractType);
|
|
|
|
type.initializeWithCopy(IGF, dest, src, concreteType, true);
|
|
dest = IGF.Builder.CreateBitCast(dest, IGF.IGM.OpaquePtrTy);
|
|
IGF.Builder.CreateRet(dest.getAddress());
|
|
return;
|
|
}
|
|
|
|
case ValueWitness::InitializeWithTake: {
|
|
Address dest = getArgAs(IGF, argv, type, "dest");
|
|
Address src = getArgAs(IGF, argv, type, "src");
|
|
getArgAsLocalSelfTypeMetadata(IGF, argv, abstractType);
|
|
|
|
type.initializeWithTake(IGF, dest, src, concreteType, true);
|
|
dest = IGF.Builder.CreateBitCast(dest, IGF.IGM.OpaquePtrTy);
|
|
IGF.Builder.CreateRet(dest.getAddress());
|
|
return;
|
|
}
|
|
|
|
case ValueWitness::GetEnumTag: {
|
|
auto &strategy = getEnumImplStrategy(IGM, concreteType);
|
|
|
|
llvm::Value *value = getArg(argv, "value");
|
|
getArgAsLocalSelfTypeMetadata(IGF, argv, abstractType);
|
|
|
|
auto enumTy = type.getStorageType()->getPointerTo();
|
|
value = IGF.Builder.CreateBitCast(value, enumTy);
|
|
auto enumAddr = type.getAddressForPointer(value);
|
|
|
|
llvm::Value *result = strategy.emitGetEnumTag(IGF, concreteType, enumAddr);
|
|
IGF.Builder.CreateRet(result);
|
|
return;
|
|
}
|
|
|
|
case ValueWitness::DestructiveProjectEnumData: {
|
|
auto &strategy = getEnumImplStrategy(IGM, concreteType);
|
|
|
|
llvm::Value *value = getArg(argv, "value");
|
|
getArgAsLocalSelfTypeMetadata(IGF, argv, abstractType);
|
|
|
|
if (!strategy.getElementsWithPayload().empty()) {
|
|
strategy.destructiveProjectDataForLoad(
|
|
IGF, concreteType,
|
|
Address(value, type.getBestKnownAlignment()));
|
|
}
|
|
|
|
IGF.Builder.CreateRetVoid();
|
|
return;
|
|
}
|
|
|
|
case ValueWitness::DestructiveInjectEnumTag: {
|
|
auto &strategy = getEnumImplStrategy(IGM, concreteType);
|
|
|
|
llvm::Value *value = getArg(argv, "value");
|
|
|
|
auto enumTy = type.getStorageType()->getPointerTo();
|
|
value = IGF.Builder.CreateBitCast(value, enumTy);
|
|
|
|
llvm::Value *tag = getArg(argv, "tag");
|
|
|
|
getArgAsLocalSelfTypeMetadata(IGF, argv, abstractType);
|
|
|
|
strategy.emitStoreTag(IGF, concreteType,
|
|
Address(value, type.getBestKnownAlignment()),
|
|
tag);
|
|
|
|
IGF.Builder.CreateRetVoid();
|
|
return;
|
|
}
|
|
|
|
case ValueWitness::GetEnumTagSinglePayload: {
|
|
llvm::Value *value = getArg(argv, "value");
|
|
auto enumTy = type.getStorageType()->getPointerTo();
|
|
value = IGF.Builder.CreateBitCast(value, enumTy);
|
|
|
|
llvm::Value *numEmptyCases = getArg(argv, "numEmptyCases");
|
|
|
|
getArgAsLocalSelfTypeMetadata(IGF, argv, abstractType);
|
|
|
|
llvm::Value *idx = type.getEnumTagSinglePayload(
|
|
IGF, numEmptyCases, Address(value, type.getBestKnownAlignment()),
|
|
concreteType, true);
|
|
IGF.Builder.CreateRet(idx);
|
|
return;
|
|
}
|
|
|
|
case ValueWitness::StoreEnumTagSinglePayload: {
|
|
llvm::Value *value = getArg(argv, "value");
|
|
auto enumTy = type.getStorageType()->getPointerTo();
|
|
value = IGF.Builder.CreateBitCast(value, enumTy);
|
|
|
|
llvm::Value *whichCase = getArg(argv, "whichCase");
|
|
llvm::Value *numEmptyCases = getArg(argv, "numEmptyCases");
|
|
|
|
getArgAsLocalSelfTypeMetadata(IGF, argv, abstractType);
|
|
|
|
type.storeEnumTagSinglePayload(IGF, whichCase, numEmptyCases,
|
|
Address(value, type.getBestKnownAlignment()),
|
|
concreteType, true);
|
|
IGF.Builder.CreateRetVoid();
|
|
return;
|
|
}
|
|
|
|
case ValueWitness::Size:
|
|
case ValueWitness::Flags:
|
|
case ValueWitness::ExtraInhabitantCount:
|
|
case ValueWitness::Stride:
|
|
llvm_unreachable("these value witnesses aren't functions");
|
|
}
|
|
llvm_unreachable("bad value witness kind!");
|
|
}
|
|
|
|
/// Return a function which takes two pointer arguments and returns
|
|
/// void immediately.
|
|
static llvm::Constant *getNoOpVoidFunction(IRGenModule &IGM) {
|
|
llvm::Type *argTys[] = { IGM.Int8PtrTy, IGM.TypeMetadataPtrTy };
|
|
return IGM.getOrCreateHelperFunction("__swift_noop_void_return",
|
|
IGM.VoidTy, argTys,
|
|
[&](IRGenFunction &IGF) {
|
|
IGF.Builder.CreateRetVoid();
|
|
});
|
|
}
|
|
|
|
/// Return a function which takes three pointer arguments and does a
|
|
/// retaining assignWithCopy on the first two: it loads a pointer from
|
|
/// the second, retains it, loads a pointer from the first, stores the
|
|
/// new pointer in the first, and releases the old pointer.
|
|
static llvm::Constant *getAssignWithCopyStrongFunction(IRGenModule &IGM) {
|
|
llvm::Type *ptrPtrTy = IGM.RefCountedPtrTy->getPointerTo();
|
|
llvm::Type *argTys[] = { ptrPtrTy, ptrPtrTy, IGM.WitnessTablePtrTy };
|
|
return IGM.getOrCreateHelperFunction("__swift_assignWithCopy_strong",
|
|
ptrPtrTy, argTys,
|
|
[&](IRGenFunction &IGF) {
|
|
auto it = IGF.CurFn->arg_begin();
|
|
Address dest(&*(it++), IGM.getPointerAlignment());
|
|
Address src(&*(it++), IGM.getPointerAlignment());
|
|
|
|
llvm::Value *newValue = IGF.Builder.CreateLoad(src, "new");
|
|
IGF.emitNativeStrongRetain(newValue, IGF.getDefaultAtomicity());
|
|
llvm::Value *oldValue = IGF.Builder.CreateLoad(dest, "old");
|
|
IGF.Builder.CreateStore(newValue, dest);
|
|
IGF.emitNativeStrongRelease(oldValue, IGF.getDefaultAtomicity());
|
|
|
|
IGF.Builder.CreateRet(dest.getAddress());
|
|
});
|
|
}
|
|
|
|
/// Return a function which takes three pointer arguments and does a
|
|
/// retaining assignWithTake on the first two: it loads a pointer from
|
|
/// the second, retains it, loads a pointer from the first, stores the
|
|
/// new pointer in the first, and releases the old pointer.
|
|
static llvm::Constant *getAssignWithTakeStrongFunction(IRGenModule &IGM) {
|
|
llvm::Type *ptrPtrTy = IGM.RefCountedPtrTy->getPointerTo();
|
|
llvm::Type *argTys[] = { ptrPtrTy, ptrPtrTy, IGM.WitnessTablePtrTy };
|
|
return IGM.getOrCreateHelperFunction("__swift_assignWithTake_strong",
|
|
ptrPtrTy, argTys,
|
|
[&](IRGenFunction &IGF) {
|
|
auto it = IGF.CurFn->arg_begin();
|
|
Address dest(&*(it++), IGM.getPointerAlignment());
|
|
Address src(&*(it++), IGM.getPointerAlignment());
|
|
|
|
llvm::Value *newValue = IGF.Builder.CreateLoad(src, "new");
|
|
llvm::Value *oldValue = IGF.Builder.CreateLoad(dest, "old");
|
|
IGF.Builder.CreateStore(newValue, dest);
|
|
IGF.emitNativeStrongRelease(oldValue, IGF.getDefaultAtomicity());
|
|
|
|
IGF.Builder.CreateRet(dest.getAddress());
|
|
});
|
|
}
|
|
|
|
/// Return a function which takes three pointer arguments and does a
|
|
/// retaining initWithCopy on the first two: it loads a pointer from
|
|
/// the second, retains it, and stores that in the first.
|
|
static llvm::Constant *getInitWithCopyStrongFunction(IRGenModule &IGM) {
|
|
llvm::Type *ptrPtrTy = IGM.RefCountedPtrTy->getPointerTo();
|
|
llvm::Type *argTys[] = { ptrPtrTy, ptrPtrTy, IGM.WitnessTablePtrTy };
|
|
return IGM.getOrCreateHelperFunction("__swift_initWithCopy_strong",
|
|
ptrPtrTy, argTys,
|
|
[&](IRGenFunction &IGF) {
|
|
auto it = IGF.CurFn->arg_begin();
|
|
Address dest(&*(it++), IGM.getPointerAlignment());
|
|
Address src(&*(it++), IGM.getPointerAlignment());
|
|
|
|
llvm::Value *newValue = IGF.Builder.CreateLoad(src, "new");
|
|
IGF.emitNativeStrongRetain(newValue, IGF.getDefaultAtomicity());
|
|
IGF.Builder.CreateStore(newValue, dest);
|
|
|
|
IGF.Builder.CreateRet(dest.getAddress());
|
|
});
|
|
}
|
|
|
|
/// Return a function which takes two pointer arguments, loads a
|
|
/// pointer from the first, and calls swift_release on it immediately.
|
|
static llvm::Constant *getDestroyStrongFunction(IRGenModule &IGM) {
|
|
llvm::Type *argTys[] = { IGM.Int8PtrPtrTy, IGM.WitnessTablePtrTy };
|
|
return IGM.getOrCreateHelperFunction("__swift_destroy_strong",
|
|
IGM.VoidTy, argTys,
|
|
[&](IRGenFunction &IGF) {
|
|
Address arg(&*IGF.CurFn->arg_begin(), IGM.getPointerAlignment());
|
|
IGF.emitNativeStrongRelease(IGF.Builder.CreateLoad(arg), IGF.getDefaultAtomicity());
|
|
IGF.Builder.CreateRetVoid();
|
|
});
|
|
}
|
|
|
|
/// Return a function which takes two pointer arguments, memcpys
|
|
/// from the second to the first, and returns the first argument.
|
|
static llvm::Constant *getMemCpyFunction(IRGenModule &IGM,
|
|
const TypeInfo &objectTI) {
|
|
// If we don't have a fixed type, use the standard copy-opaque-POD
|
|
// routine. It's not quite clear how in practice we'll be able to
|
|
// conclude that something is known-POD without knowing its size,
|
|
// but it's (1) conceivable and (2) needed as a general export anyway.
|
|
auto *fixedTI = dyn_cast<FixedTypeInfo>(&objectTI);
|
|
if (!fixedTI) return IGM.getCopyPODFn();
|
|
|
|
// We need to unique by both size and alignment. Note that we're
|
|
// assuming that it's safe to call a function that returns a pointer
|
|
// at a site that assumes the function returns void.
|
|
llvm::SmallString<40> name;
|
|
{
|
|
llvm::raw_svector_ostream nameStream(name);
|
|
nameStream << "__swift_memcpy";
|
|
nameStream << fixedTI->getFixedSize().getValue();
|
|
nameStream << '_';
|
|
nameStream << fixedTI->getFixedAlignment().getValue();
|
|
}
|
|
|
|
llvm::Type *argTys[] = { IGM.Int8PtrTy, IGM.Int8PtrTy, IGM.TypeMetadataPtrTy };
|
|
return IGM.getOrCreateHelperFunction(name, IGM.Int8PtrTy, argTys,
|
|
[&](IRGenFunction &IGF) {
|
|
auto it = IGF.CurFn->arg_begin();
|
|
Address dest(&*it++, fixedTI->getFixedAlignment());
|
|
Address src(&*it++, fixedTI->getFixedAlignment());
|
|
IGF.emitMemCpy(dest, src, fixedTI->getFixedSize());
|
|
IGF.Builder.CreateRet(dest.getAddress());
|
|
});
|
|
}
|
|
|
|
/// Find a witness to the fact that a type is a value type.
|
|
/// Always adds an i8*.
|
|
static void addValueWitness(IRGenModule &IGM,
|
|
ConstantStructBuilder &B,
|
|
ValueWitness index,
|
|
FixedPacking packing,
|
|
CanType abstractType,
|
|
SILType concreteType,
|
|
const TypeInfo &concreteTI) {
|
|
auto addFunction = [&](llvm::Constant *fn) {
|
|
B.addBitCast(fn, IGM.Int8PtrTy);
|
|
};
|
|
|
|
// Try to use a standard function.
|
|
switch (index) {
|
|
case ValueWitness::Destroy:
|
|
if (concreteTI.isPOD(ResilienceExpansion::Maximal)) {
|
|
return addFunction(getNoOpVoidFunction(IGM));
|
|
} else if (concreteTI.isSingleSwiftRetainablePointer(ResilienceExpansion::Maximal)) {
|
|
return addFunction(getDestroyStrongFunction(IGM));
|
|
}
|
|
goto standard;
|
|
|
|
case ValueWitness::InitializeBufferWithCopyOfBuffer:
|
|
if (packing == FixedPacking::OffsetZero) {
|
|
if (concreteTI.isPOD(ResilienceExpansion::Maximal)) {
|
|
return addFunction(getMemCpyFunction(IGM, concreteTI));
|
|
} else if (concreteTI.isSingleSwiftRetainablePointer(ResilienceExpansion::Maximal)) {
|
|
return addFunction(getInitWithCopyStrongFunction(IGM));
|
|
}
|
|
}
|
|
goto standard;
|
|
|
|
case ValueWitness::InitializeWithTake:
|
|
if (concreteTI.isBitwiseTakable(ResilienceExpansion::Maximal)) {
|
|
return addFunction(getMemCpyFunction(IGM, concreteTI));
|
|
}
|
|
goto standard;
|
|
|
|
case ValueWitness::AssignWithCopy:
|
|
if (concreteTI.isPOD(ResilienceExpansion::Maximal)) {
|
|
return addFunction(getMemCpyFunction(IGM, concreteTI));
|
|
} else if (concreteTI.isSingleSwiftRetainablePointer(ResilienceExpansion::Maximal)) {
|
|
return addFunction(getAssignWithCopyStrongFunction(IGM));
|
|
}
|
|
goto standard;
|
|
|
|
case ValueWitness::AssignWithTake:
|
|
if (concreteTI.isPOD(ResilienceExpansion::Maximal)) {
|
|
return addFunction(getMemCpyFunction(IGM, concreteTI));
|
|
} else if (concreteTI.isSingleSwiftRetainablePointer(ResilienceExpansion::Maximal)) {
|
|
return addFunction(getAssignWithTakeStrongFunction(IGM));
|
|
}
|
|
goto standard;
|
|
|
|
case ValueWitness::InitializeWithCopy:
|
|
if (concreteTI.isPOD(ResilienceExpansion::Maximal)) {
|
|
return addFunction(getMemCpyFunction(IGM, concreteTI));
|
|
} else if (concreteTI.isSingleSwiftRetainablePointer(ResilienceExpansion::Maximal)) {
|
|
return addFunction(getInitWithCopyStrongFunction(IGM));
|
|
}
|
|
goto standard;
|
|
|
|
case ValueWitness::Size: {
|
|
if (auto value = concreteTI.getStaticSize(IGM))
|
|
return B.add(value);
|
|
|
|
// Just fill in 0 here if the type can't be statically laid out.
|
|
return B.addSize(Size(0));
|
|
}
|
|
|
|
case ValueWitness::Flags: {
|
|
ValueWitnessFlags flags;
|
|
|
|
// If we locally know that the type has fixed layout, we can emit
|
|
// meaningful flags for it.
|
|
if (auto *fixedTI = dyn_cast<FixedTypeInfo>(&concreteTI)) {
|
|
assert(packing == FixedPacking::OffsetZero ||
|
|
packing == FixedPacking::Allocate);
|
|
bool isInline = packing == FixedPacking::OffsetZero;
|
|
bool isBitwiseTakable =
|
|
fixedTI->isBitwiseTakable(ResilienceExpansion::Maximal);
|
|
assert(isBitwiseTakable || !isInline);
|
|
flags = flags.withAlignment(fixedTI->getFixedAlignment().getValue())
|
|
.withPOD(fixedTI->isPOD(ResilienceExpansion::Maximal))
|
|
.withInlineStorage(isInline)
|
|
.withBitwiseTakable(isBitwiseTakable);
|
|
} else {
|
|
flags = flags.withIncomplete(true);
|
|
}
|
|
|
|
if (concreteType.getEnumOrBoundGenericEnum())
|
|
flags = flags.withEnumWitnesses(true);
|
|
|
|
return B.addInt32(flags.getOpaqueValue());
|
|
}
|
|
|
|
case ValueWitness::ExtraInhabitantCount: {
|
|
unsigned value = 0;
|
|
if (auto *fixedTI = dyn_cast<FixedTypeInfo>(&concreteTI)) {
|
|
value = fixedTI->getFixedExtraInhabitantCount(IGM);
|
|
}
|
|
return B.addInt32(value);
|
|
}
|
|
|
|
case ValueWitness::Stride: {
|
|
if (auto value = concreteTI.getStaticStride(IGM))
|
|
return B.add(value);
|
|
|
|
// Just fill in null here if the type can't be statically laid out.
|
|
return B.addSize(Size(0));
|
|
}
|
|
|
|
case ValueWitness::GetEnumTagSinglePayload:
|
|
case ValueWitness::StoreEnumTagSinglePayload: {
|
|
goto standard;
|
|
}
|
|
|
|
case ValueWitness::GetEnumTag:
|
|
case ValueWitness::DestructiveProjectEnumData:
|
|
case ValueWitness::DestructiveInjectEnumTag:
|
|
assert(concreteType.getEnumOrBoundGenericEnum());
|
|
goto standard;
|
|
}
|
|
llvm_unreachable("bad value witness kind");
|
|
|
|
standard:
|
|
llvm::Function *fn =
|
|
IGM.getAddrOfValueWitness(abstractType, index, ForDefinition);
|
|
if (fn->empty())
|
|
buildValueWitnessFunction(IGM, fn, index, packing, abstractType,
|
|
concreteType, concreteTI);
|
|
addFunction(fn);
|
|
}
|
|
|
|
static bool shouldAddEnumWitnesses(CanType abstractType) {
|
|
// Needs to handle UnboundGenericType.
|
|
return dyn_cast_or_null<EnumDecl>(abstractType.getAnyNominal()) != nullptr;
|
|
}
|
|
|
|
static llvm::StructType *getValueWitnessTableType(IRGenModule &IGM,
|
|
CanType abstractType) {
|
|
return shouldAddEnumWitnesses(abstractType)
|
|
? IGM.getEnumValueWitnessTableTy()
|
|
: IGM.getValueWitnessTableTy();
|
|
}
|
|
|
|
/// Collect the value witnesses for a particular type.
|
|
static void addValueWitnesses(IRGenModule &IGM,
|
|
ConstantStructBuilder &B,
|
|
FixedPacking packing,
|
|
CanType abstractType,
|
|
SILType concreteType,
|
|
const TypeInfo &concreteTI) {
|
|
for (unsigned i = 0; i != NumRequiredValueWitnesses; ++i) {
|
|
addValueWitness(IGM, B, ValueWitness(i), packing,
|
|
abstractType, concreteType, concreteTI);
|
|
}
|
|
if (shouldAddEnumWitnesses(abstractType)) {
|
|
for (auto i = unsigned(ValueWitness::First_EnumValueWitness);
|
|
i <= unsigned(ValueWitness::Last_EnumValueWitness);
|
|
++i) {
|
|
addValueWitness(IGM, B, ValueWitness(i), packing,
|
|
abstractType, concreteType, concreteTI);
|
|
}
|
|
}
|
|
}
|
|
|
|
/// True if a type has a generic-parameter-dependent value witness table.
|
|
/// Currently, this is true if the size and/or alignment of the type is
|
|
/// dependent on its generic parameters.
|
|
bool irgen::hasDependentValueWitnessTable(IRGenModule &IGM, CanType ty) {
|
|
return !IGM.getTypeInfoForUnlowered(getFormalTypeInContext(ty)).isFixedSize();
|
|
}
|
|
|
|
static void addValueWitnessesForAbstractType(IRGenModule &IGM,
|
|
ConstantStructBuilder &B,
|
|
CanType abstractType,
|
|
bool &canBeConstant) {
|
|
CanType concreteFormalType = getFormalTypeInContext(abstractType);
|
|
|
|
auto concreteLoweredType = IGM.getLoweredType(concreteFormalType);
|
|
auto &concreteTI = IGM.getTypeInfo(concreteLoweredType);
|
|
FixedPacking packing = concreteTI.getFixedPacking(IGM);
|
|
|
|
// For now, assume that we never have any interest in dynamically
|
|
// changing the value witnesses for something that's fixed-layout.
|
|
canBeConstant = concreteTI.isFixedSize();
|
|
|
|
addValueWitnesses(IGM, B, packing, abstractType,
|
|
concreteLoweredType, concreteTI);
|
|
}
|
|
|
|
static constexpr uint64_t sizeAndAlignment(Size size, Alignment alignment) {
|
|
return ((uint64_t)size.getValue() << 32) | alignment.getValue();
|
|
}
|
|
|
|
/// Return a reference to a known value witness table from the runtime
|
|
/// that's suitable for the given type, if there is one, or return null
|
|
/// if we should emit a new one.
|
|
static ConstantReference
|
|
getAddrOfKnownValueWitnessTable(IRGenModule &IGM, CanType type,
|
|
bool relativeReference) {
|
|
// Native PE binaries shouldn't reference data symbols across DLLs, so disable
|
|
// this on Windows, unless we're forming a relative indirectable reference.
|
|
if (IGM.useDllStorage() && !relativeReference)
|
|
return {};
|
|
|
|
if (auto nom = type->getAnyNominal()) {
|
|
// TODO: Non-C enums have extra inhabitants and also need additional value
|
|
// witnesses for their tag manipulation (except when they're empty, in
|
|
// which case values never exist to witness).
|
|
if (auto enumDecl = dyn_cast<EnumDecl>(nom))
|
|
if (!enumDecl->isObjC() && !type->isUninhabited())
|
|
return {};
|
|
}
|
|
|
|
auto &C = IGM.Context;
|
|
|
|
type = getFormalTypeInContext(type);
|
|
|
|
auto &ti = IGM.getTypeInfoForUnlowered(AbstractionPattern::getOpaque(), type);
|
|
|
|
// We only have witnesses for fixed type info.
|
|
auto *fixedTI = dyn_cast<FixedTypeInfo>(&ti);
|
|
if (!fixedTI)
|
|
return {};
|
|
|
|
CanType witnessSurrogate;
|
|
ReferenceCounting refCounting;
|
|
|
|
// Empty types can use empty tuple witnesses.
|
|
if (ti.isKnownEmpty(ResilienceExpansion::Maximal)) {
|
|
witnessSurrogate = TupleType::getEmpty(C);
|
|
// Handle common POD type layouts.
|
|
} else if (fixedTI->isPOD(ResilienceExpansion::Maximal)
|
|
&& fixedTI->getFixedExtraInhabitantCount(IGM) == 0) {
|
|
// Reuse one of the integer witnesses if applicable.
|
|
switch (sizeAndAlignment(fixedTI->getFixedSize(),
|
|
fixedTI->getFixedAlignment())) {
|
|
case sizeAndAlignment(Size(0), Alignment(1)):
|
|
witnessSurrogate = TupleType::getEmpty(C);
|
|
break;
|
|
case sizeAndAlignment(Size(1), Alignment(1)):
|
|
witnessSurrogate = BuiltinIntegerType::get(8, C)->getCanonicalType();
|
|
break;
|
|
case sizeAndAlignment(Size(2), Alignment(2)):
|
|
witnessSurrogate = BuiltinIntegerType::get(16, C)->getCanonicalType();
|
|
break;
|
|
case sizeAndAlignment(Size(4), Alignment(4)):
|
|
witnessSurrogate = BuiltinIntegerType::get(32, C)->getCanonicalType();
|
|
break;
|
|
case sizeAndAlignment(Size(8), Alignment(8)):
|
|
witnessSurrogate = BuiltinIntegerType::get(64, C)->getCanonicalType();
|
|
break;
|
|
case sizeAndAlignment(Size(16), Alignment(16)):
|
|
witnessSurrogate = BuiltinIntegerType::get(128, C)->getCanonicalType();
|
|
break;
|
|
case sizeAndAlignment(Size(32), Alignment(32)):
|
|
witnessSurrogate = BuiltinIntegerType::get(256, C)->getCanonicalType();
|
|
break;
|
|
case sizeAndAlignment(Size(64), Alignment(64)):
|
|
witnessSurrogate = BuiltinIntegerType::get(512, C)->getCanonicalType();
|
|
break;
|
|
}
|
|
} else if (fixedTI->isSingleRetainablePointer(ResilienceExpansion::Maximal,
|
|
&refCounting)) {
|
|
switch (refCounting) {
|
|
case ReferenceCounting::Native:
|
|
witnessSurrogate = C.TheNativeObjectType;
|
|
break;
|
|
case ReferenceCounting::ObjC:
|
|
case ReferenceCounting::Block:
|
|
case ReferenceCounting::Unknown:
|
|
witnessSurrogate = C.TheUnknownObjectType;
|
|
break;
|
|
case ReferenceCounting::Bridge:
|
|
witnessSurrogate = C.TheBridgeObjectType;
|
|
break;
|
|
case ReferenceCounting::Error:
|
|
break;
|
|
}
|
|
}
|
|
|
|
if (witnessSurrogate) {
|
|
if (relativeReference) {
|
|
return IGM.getAddrOfLLVMVariableOrGOTEquivalent(
|
|
LinkEntity::forValueWitnessTable(witnessSurrogate));
|
|
} else {
|
|
return {IGM.getAddrOfValueWitnessTable(witnessSurrogate),
|
|
ConstantReference::Direct};
|
|
}
|
|
}
|
|
return {};
|
|
}
|
|
|
|
/// Emit a value-witness table for the given type.
|
|
ConstantReference irgen::emitValueWitnessTable(IRGenModule &IGM,
|
|
CanType abstractType,
|
|
bool isPattern,
|
|
bool relativeReference) {
|
|
// We shouldn't emit global value witness tables for generic type instances.
|
|
assert(!isa<BoundGenericType>(abstractType) &&
|
|
"emitting VWT for generic instance");
|
|
|
|
// See if we can use a prefab witness table from the runtime.
|
|
if (!isPattern) {
|
|
if (auto known = getAddrOfKnownValueWitnessTable(IGM, abstractType,
|
|
relativeReference)) {
|
|
return known;
|
|
}
|
|
}
|
|
|
|
// We should never be making a pattern if the layout isn't fixed.
|
|
// The reverse can be true for types whose layout depends on
|
|
// resilient types.
|
|
assert((!isPattern || hasDependentValueWitnessTable(IGM, abstractType)) &&
|
|
"emitting VWT pattern for fixed-layout type");
|
|
|
|
ConstantInitBuilder builder(IGM);
|
|
auto witnesses =
|
|
builder.beginStruct(getValueWitnessTableType(IGM, abstractType));
|
|
|
|
bool canBeConstant = false;
|
|
addValueWitnessesForAbstractType(IGM, witnesses, abstractType, canBeConstant);
|
|
|
|
// If this is just an instantiation pattern, we should never be modifying
|
|
// it in-place.
|
|
if (isPattern) canBeConstant = true;
|
|
|
|
auto addr = IGM.getAddrOfValueWitnessTable(abstractType,
|
|
witnesses.finishAndCreateFuture());
|
|
auto global = cast<llvm::GlobalVariable>(addr);
|
|
global->setConstant(canBeConstant);
|
|
|
|
return {llvm::ConstantExpr::getBitCast(global, IGM.WitnessTablePtrTy),
|
|
ConstantReference::Direct};
|
|
}
|
|
|
|
llvm::Constant *IRGenModule::emitFixedTypeLayout(CanType t,
|
|
const FixedTypeInfo &ti) {
|
|
auto silTy = SILType::getPrimitiveAddressType(t);
|
|
// Collect the interesting information that gets encoded in a type layout
|
|
// record, to see if there's one we can reuse.
|
|
unsigned size = ti.getFixedSize().getValue();
|
|
unsigned align = ti.getFixedAlignment().getValue();
|
|
|
|
bool pod = ti.isPOD(ResilienceExpansion::Maximal);
|
|
bool bt = ti.isBitwiseTakable(ResilienceExpansion::Maximal);
|
|
unsigned numExtraInhabitants = ti.getFixedExtraInhabitantCount(*this);
|
|
|
|
// Try to use common type layouts exported by the runtime.
|
|
llvm::Constant *commonValueWitnessTable = nullptr;
|
|
if (pod && bt && numExtraInhabitants == 0) {
|
|
if (size == 0)
|
|
commonValueWitnessTable =
|
|
getAddrOfValueWitnessTable(Context.TheEmptyTupleType);
|
|
if ( (size == 1 && align == 1)
|
|
|| (size == 2 && align == 2)
|
|
|| (size == 4 && align == 4)
|
|
|| (size == 8 && align == 8)
|
|
|| (size == 16 && align == 16)
|
|
|| (size == 32 && align == 32))
|
|
commonValueWitnessTable =
|
|
getAddrOfValueWitnessTable(BuiltinIntegerType::get(size * 8, Context)
|
|
->getCanonicalType());
|
|
}
|
|
|
|
if (commonValueWitnessTable) {
|
|
auto index = llvm::ConstantInt::get(Int32Ty,
|
|
(unsigned)ValueWitness::First_TypeLayoutWitness);
|
|
return llvm::ConstantExpr::getGetElementPtr(Int8PtrTy,
|
|
commonValueWitnessTable,
|
|
index);
|
|
}
|
|
|
|
// Otherwise, see if a layout has been emitted with these characteristics
|
|
// already.
|
|
FixedLayoutKey key{size, numExtraInhabitants, align, pod, bt};
|
|
|
|
auto found = PrivateFixedLayouts.find(key);
|
|
if (found != PrivateFixedLayouts.end())
|
|
return found->second;
|
|
|
|
// Emit the layout values.
|
|
ConstantInitBuilder builder(*this);
|
|
auto witnesses = builder.beginStruct();
|
|
FixedPacking packing = ti.getFixedPacking(*this);
|
|
for (auto witness = ValueWitness::First_TypeLayoutWitness;
|
|
witness <= ValueWitness::Last_RequiredTypeLayoutWitness;
|
|
witness = ValueWitness(unsigned(witness) + 1)) {
|
|
addValueWitness(*this, witnesses, witness, packing, t, silTy, ti);
|
|
}
|
|
|
|
auto layoutVar
|
|
= witnesses.finishAndCreateGlobal(
|
|
"type_layout_" + llvm::Twine(size)
|
|
+ "_" + llvm::Twine(align)
|
|
+ "_" + llvm::Twine::utohexstr(numExtraInhabitants)
|
|
+ (pod ? "_pod" :
|
|
bt ? "_bt" : ""),
|
|
getPointerAlignment(),
|
|
/*constant*/ true,
|
|
llvm::GlobalValue::PrivateLinkage);
|
|
|
|
// Cast to the standard currency type for type layouts.
|
|
auto layout = llvm::ConstantExpr::getBitCast(layoutVar, Int8PtrPtrTy);
|
|
|
|
PrivateFixedLayouts.insert({key, layout});
|
|
return layout;
|
|
}
|
|
|
|
FixedPacking TypeInfo::getFixedPacking(IRGenModule &IGM) const {
|
|
auto fixedTI = dyn_cast<FixedTypeInfo>(this);
|
|
|
|
// If the type isn't fixed, we have to do something dynamic.
|
|
// FIXME: some types are provably too big (or aligned) to be
|
|
// allocated inline.
|
|
if (!fixedTI)
|
|
return FixedPacking::Dynamic;
|
|
|
|
// By convention we only store bitwise takable values inline.
|
|
if (!fixedTI->isBitwiseTakable(ResilienceExpansion::Maximal))
|
|
return FixedPacking::Allocate;
|
|
|
|
Size bufferSize = getFixedBufferSize(IGM);
|
|
Size requiredSize = fixedTI->getFixedSize();
|
|
|
|
// Flat out, if we need more space than the buffer provides,
|
|
// we always have to allocate.
|
|
// FIXME: there might be some interesting cases where this
|
|
// is suboptimal for enums.
|
|
if (requiredSize > bufferSize)
|
|
return FixedPacking::Allocate;
|
|
|
|
Alignment bufferAlign = getFixedBufferAlignment(IGM);
|
|
Alignment requiredAlign = fixedTI->getFixedAlignment();
|
|
|
|
// If the buffer alignment is good enough for the type, great.
|
|
if (bufferAlign >= requiredAlign)
|
|
return FixedPacking::OffsetZero;
|
|
|
|
// TODO: consider using a slower mode that dynamically checks
|
|
// whether the buffer size is small enough.
|
|
|
|
// Otherwise we're stuck and have to separately allocate.
|
|
return FixedPacking::Allocate;
|
|
}
|
|
|
|
Address TypeInfo::indexArray(IRGenFunction &IGF, Address base,
|
|
llvm::Value *index, SILType T) const {
|
|
// The stride of a Swift type may not match its LLVM size. If we know we have
|
|
// a fixed stride different from our size, or we have a dynamic size,
|
|
// do a byte-level GEP with the proper stride.
|
|
const auto *fixedTI = dyn_cast<FixedTypeInfo>(this);
|
|
|
|
llvm::Value *destValue = nullptr;
|
|
Size stride(1);
|
|
|
|
// TODO: Arrays currently lower-bound the stride to 1.
|
|
if (!fixedTI || fixedTI->getFixedStride() != fixedTI->getFixedSize()) {
|
|
llvm::Value *byteAddr = IGF.Builder.CreateBitCast(base.getAddress(),
|
|
IGF.IGM.Int8PtrTy);
|
|
llvm::Value *size = getStride(IGF, T);
|
|
if (size->getType() != index->getType())
|
|
size = IGF.Builder.CreateZExtOrTrunc(size, index->getType());
|
|
llvm::Value *distance = IGF.Builder.CreateNSWMul(index, size);
|
|
destValue = IGF.Builder.CreateInBoundsGEP(byteAddr, distance);
|
|
destValue = IGF.Builder.CreateBitCast(destValue, base.getType());
|
|
} else {
|
|
// We don't expose a non-inbounds GEP operation.
|
|
destValue = IGF.Builder.CreateInBoundsGEP(base.getAddress(), index);
|
|
stride = fixedTI->getFixedStride();
|
|
}
|
|
if (auto *IndexConst = dyn_cast<llvm::ConstantInt>(index)) {
|
|
// If we know the indexing value, we can get a better guess on the
|
|
// alignment.
|
|
// This even works if the stride is not known (and assumed to be 1).
|
|
stride *= IndexConst->getValue().getZExtValue();
|
|
}
|
|
Alignment Align = base.getAlignment().alignmentAtOffset(stride);
|
|
return Address(destValue, Align);
|
|
}
|
|
|
|
Address TypeInfo::roundUpToTypeAlignment(IRGenFunction &IGF, Address base,
|
|
SILType T) const {
|
|
Alignment Align = base.getAlignment();
|
|
llvm::Value *TyAlignMask = getAlignmentMask(IGF, T);
|
|
if (auto *TyAlignMaskConst = dyn_cast<llvm::ConstantInt>(TyAlignMask)) {
|
|
Alignment TyAlign(TyAlignMaskConst->getZExtValue() + 1);
|
|
|
|
// No need to align if the base is already aligned.
|
|
if (TyAlign <= Align)
|
|
return base;
|
|
}
|
|
llvm::Value *Addr = base.getAddress();
|
|
Addr = IGF.Builder.CreatePtrToInt(Addr, IGF.IGM.IntPtrTy);
|
|
Addr = IGF.Builder.CreateNUWAdd(Addr, TyAlignMask);
|
|
llvm::Value *InvertedMask = IGF.Builder.CreateNot(TyAlignMask);
|
|
Addr = IGF.Builder.CreateAnd(Addr, InvertedMask);
|
|
Addr = IGF.Builder.CreateIntToPtr(Addr, base.getAddress()->getType());
|
|
return Address(Addr, Align);
|
|
}
|
|
|
|
void TypeInfo::destroyArray(IRGenFunction &IGF, Address array,
|
|
llvm::Value *count, SILType T) const {
|
|
if (isPOD(ResilienceExpansion::Maximal))
|
|
return;
|
|
|
|
emitDestroyArrayCall(IGF, T, array, count);
|
|
}
|
|
|
|
void TypeInfo::initializeArrayWithCopy(IRGenFunction &IGF,
|
|
Address dest, Address src,
|
|
llvm::Value *count, SILType T) const {
|
|
if (isPOD(ResilienceExpansion::Maximal)) {
|
|
llvm::Value *stride = getStride(IGF, T);
|
|
llvm::Value *byteCount = IGF.Builder.CreateNUWMul(stride, count);
|
|
IGF.Builder.CreateMemCpy(dest.getAddress(),
|
|
dest.getAlignment().getValue(),
|
|
src.getAddress(),
|
|
src.getAlignment().getValue(), byteCount);
|
|
return;
|
|
}
|
|
|
|
emitInitializeArrayWithCopyCall(IGF, T, dest, src, count);
|
|
}
|
|
|
|
void TypeInfo::initializeArrayWithTakeNoAlias(IRGenFunction &IGF, Address dest,
|
|
Address src, llvm::Value *count,
|
|
SILType T) const {
|
|
if (isBitwiseTakable(ResilienceExpansion::Maximal)) {
|
|
llvm::Value *stride = getStride(IGF, T);
|
|
llvm::Value *byteCount = IGF.Builder.CreateNUWMul(stride, count);
|
|
IGF.Builder.CreateMemCpy(dest.getAddress(),
|
|
dest.getAlignment().getValue(),
|
|
src.getAddress(),
|
|
src.getAlignment().getValue(), byteCount);
|
|
return;
|
|
}
|
|
|
|
emitInitializeArrayWithTakeNoAliasCall(IGF, T, dest, src, count);
|
|
}
|
|
|
|
void TypeInfo::initializeArrayWithTakeFrontToBack(IRGenFunction &IGF,
|
|
Address dest, Address src,
|
|
llvm::Value *count, SILType T)
|
|
const {
|
|
if (isBitwiseTakable(ResilienceExpansion::Maximal)) {
|
|
llvm::Value *stride = getStride(IGF, T);
|
|
llvm::Value *byteCount = IGF.Builder.CreateNUWMul(stride, count);
|
|
IGF.Builder.CreateMemMove(dest.getAddress(), dest.getAlignment().getValue(),
|
|
src.getAddress(), src.getAlignment().getValue(),
|
|
byteCount);
|
|
return;
|
|
}
|
|
|
|
emitInitializeArrayWithTakeFrontToBackCall(IGF, T, dest, src, count);
|
|
}
|
|
|
|
void TypeInfo::initializeArrayWithTakeBackToFront(IRGenFunction &IGF,
|
|
Address dest, Address src,
|
|
llvm::Value *count, SILType T)
|
|
const {
|
|
if (isBitwiseTakable(ResilienceExpansion::Maximal)) {
|
|
llvm::Value *stride = getStride(IGF, T);
|
|
llvm::Value *byteCount = IGF.Builder.CreateNUWMul(stride, count);
|
|
IGF.Builder.CreateMemMove(dest.getAddress(), dest.getAlignment().getValue(),
|
|
src.getAddress(), src.getAlignment().getValue(),
|
|
byteCount);
|
|
return;
|
|
}
|
|
|
|
emitInitializeArrayWithTakeBackToFrontCall(IGF, T, dest, src, count);
|
|
}
|
|
|
|
void TypeInfo::assignArrayWithCopyNoAlias(IRGenFunction &IGF, Address dest,
|
|
Address src, llvm::Value *count,
|
|
SILType T) const {
|
|
if (isPOD(ResilienceExpansion::Maximal)) {
|
|
llvm::Value *stride = getStride(IGF, T);
|
|
llvm::Value *byteCount = IGF.Builder.CreateNUWMul(stride, count);
|
|
IGF.Builder.CreateMemCpy(dest.getAddress(),
|
|
dest.getAlignment().getValue(),
|
|
src.getAddress(),
|
|
src.getAlignment().getValue(), byteCount);
|
|
return;
|
|
}
|
|
|
|
emitAssignArrayWithCopyNoAliasCall(IGF, T, dest, src, count);
|
|
}
|
|
|
|
void TypeInfo::assignArrayWithCopyFrontToBack(IRGenFunction &IGF, Address dest,
|
|
Address src, llvm::Value *count,
|
|
SILType T) const {
|
|
if (isPOD(ResilienceExpansion::Maximal)) {
|
|
llvm::Value *stride = getStride(IGF, T);
|
|
llvm::Value *byteCount = IGF.Builder.CreateNUWMul(stride, count);
|
|
IGF.Builder.CreateMemMove(dest.getAddress(), dest.getAlignment().getValue(),
|
|
src.getAddress(), src.getAlignment().getValue(),
|
|
byteCount);
|
|
return;
|
|
}
|
|
|
|
emitAssignArrayWithCopyFrontToBackCall(IGF, T, dest, src, count);
|
|
}
|
|
|
|
void TypeInfo::assignArrayWithCopyBackToFront(IRGenFunction &IGF, Address dest,
|
|
Address src, llvm::Value *count,
|
|
SILType T) const {
|
|
if (isPOD(ResilienceExpansion::Maximal)) {
|
|
llvm::Value *stride = getStride(IGF, T);
|
|
llvm::Value *byteCount = IGF.Builder.CreateNUWMul(stride, count);
|
|
IGF.Builder.CreateMemMove(dest.getAddress(), dest.getAlignment().getValue(),
|
|
src.getAddress(), src.getAlignment().getValue(),
|
|
byteCount);
|
|
return;
|
|
}
|
|
|
|
emitAssignArrayWithCopyBackToFrontCall(IGF, T, dest, src, count);
|
|
}
|
|
|
|
void TypeInfo::assignArrayWithTake(IRGenFunction &IGF, Address dest,
|
|
Address src, llvm::Value *count,
|
|
SILType T) const {
|
|
if (isPOD(ResilienceExpansion::Maximal)) {
|
|
llvm::Value *stride = getStride(IGF, T);
|
|
llvm::Value *byteCount = IGF.Builder.CreateNUWMul(stride, count);
|
|
IGF.Builder.CreateMemCpy(dest.getAddress(),
|
|
dest.getAlignment().getValue(),
|
|
src.getAddress(),
|
|
src.getAlignment().getValue(), byteCount);
|
|
return;
|
|
}
|
|
|
|
emitAssignArrayWithTakeCall(IGF, T, dest, src, count);
|
|
}
|
|
|
|
void TypeInfo::collectMetadataForOutlining(OutliningMetadataCollector &c,
|
|
SILType T) const {
|
|
auto canType = T.getASTType();
|
|
assert(!canType->is<ArchetypeType>() && "Did not expect an ArchetypeType");
|
|
(void)canType;
|
|
}
|