mirror of
https://github.com/c64scene-ar/llvm-6502.git
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Apparently, the style needs to be agreed upon first. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@240390 91177308-0d34-0410-b5e6-96231b3b80d8
1814 lines
63 KiB
C++
1814 lines
63 KiB
C++
//===- lib/Linker/LinkModules.cpp - Module Linker Implementation ----------===//
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//
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// The LLVM Compiler Infrastructure
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//
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// This file is distributed under the University of Illinois Open Source
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// License. See LICENSE.TXT for details.
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//
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//===----------------------------------------------------------------------===//
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//
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// This file implements the LLVM module linker.
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//
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//===----------------------------------------------------------------------===//
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#include "llvm/Linker/Linker.h"
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#include "llvm-c/Linker.h"
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#include "llvm/ADT/Hashing.h"
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#include "llvm/ADT/Optional.h"
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#include "llvm/ADT/SetVector.h"
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#include "llvm/ADT/SmallString.h"
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#include "llvm/ADT/Statistic.h"
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#include "llvm/ADT/Triple.h"
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#include "llvm/IR/Constants.h"
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#include "llvm/IR/DebugInfo.h"
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#include "llvm/IR/DiagnosticInfo.h"
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#include "llvm/IR/DiagnosticPrinter.h"
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#include "llvm/IR/LLVMContext.h"
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#include "llvm/IR/Module.h"
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#include "llvm/IR/TypeFinder.h"
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#include "llvm/Support/CommandLine.h"
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#include "llvm/Support/Debug.h"
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#include "llvm/Support/raw_ostream.h"
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#include "llvm/Transforms/Utils/Cloning.h"
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#include <cctype>
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#include <tuple>
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using namespace llvm;
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//===----------------------------------------------------------------------===//
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// TypeMap implementation.
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//===----------------------------------------------------------------------===//
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namespace {
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class TypeMapTy : public ValueMapTypeRemapper {
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/// This is a mapping from a source type to a destination type to use.
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DenseMap<Type*, Type*> MappedTypes;
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/// When checking to see if two subgraphs are isomorphic, we speculatively
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/// add types to MappedTypes, but keep track of them here in case we need to
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/// roll back.
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SmallVector<Type*, 16> SpeculativeTypes;
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SmallVector<StructType*, 16> SpeculativeDstOpaqueTypes;
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/// This is a list of non-opaque structs in the source module that are mapped
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/// to an opaque struct in the destination module.
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SmallVector<StructType*, 16> SrcDefinitionsToResolve;
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/// This is the set of opaque types in the destination modules who are
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/// getting a body from the source module.
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SmallPtrSet<StructType*, 16> DstResolvedOpaqueTypes;
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public:
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TypeMapTy(Linker::IdentifiedStructTypeSet &DstStructTypesSet)
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: DstStructTypesSet(DstStructTypesSet) {}
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Linker::IdentifiedStructTypeSet &DstStructTypesSet;
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/// Indicate that the specified type in the destination module is conceptually
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/// equivalent to the specified type in the source module.
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void addTypeMapping(Type *DstTy, Type *SrcTy);
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/// Produce a body for an opaque type in the dest module from a type
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/// definition in the source module.
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void linkDefinedTypeBodies();
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/// Return the mapped type to use for the specified input type from the
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/// source module.
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Type *get(Type *SrcTy);
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Type *get(Type *SrcTy, SmallPtrSet<StructType *, 8> &Visited);
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void finishType(StructType *DTy, StructType *STy, ArrayRef<Type *> ETypes);
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FunctionType *get(FunctionType *T) {
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return cast<FunctionType>(get((Type *)T));
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}
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/// Dump out the type map for debugging purposes.
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void dump() const {
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for (auto &Pair : MappedTypes) {
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dbgs() << "TypeMap: ";
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Pair.first->print(dbgs());
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dbgs() << " => ";
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Pair.second->print(dbgs());
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dbgs() << '\n';
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}
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}
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private:
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Type *remapType(Type *SrcTy) override { return get(SrcTy); }
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bool areTypesIsomorphic(Type *DstTy, Type *SrcTy);
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};
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}
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void TypeMapTy::addTypeMapping(Type *DstTy, Type *SrcTy) {
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assert(SpeculativeTypes.empty());
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assert(SpeculativeDstOpaqueTypes.empty());
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// Check to see if these types are recursively isomorphic and establish a
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// mapping between them if so.
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if (!areTypesIsomorphic(DstTy, SrcTy)) {
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// Oops, they aren't isomorphic. Just discard this request by rolling out
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// any speculative mappings we've established.
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for (Type *Ty : SpeculativeTypes)
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MappedTypes.erase(Ty);
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SrcDefinitionsToResolve.resize(SrcDefinitionsToResolve.size() -
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SpeculativeDstOpaqueTypes.size());
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for (StructType *Ty : SpeculativeDstOpaqueTypes)
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DstResolvedOpaqueTypes.erase(Ty);
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} else {
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for (Type *Ty : SpeculativeTypes)
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if (auto *STy = dyn_cast<StructType>(Ty))
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if (STy->hasName())
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STy->setName("");
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}
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SpeculativeTypes.clear();
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SpeculativeDstOpaqueTypes.clear();
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}
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/// Recursively walk this pair of types, returning true if they are isomorphic,
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/// false if they are not.
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bool TypeMapTy::areTypesIsomorphic(Type *DstTy, Type *SrcTy) {
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// Two types with differing kinds are clearly not isomorphic.
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if (DstTy->getTypeID() != SrcTy->getTypeID())
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return false;
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// If we have an entry in the MappedTypes table, then we have our answer.
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Type *&Entry = MappedTypes[SrcTy];
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if (Entry)
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return Entry == DstTy;
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// Two identical types are clearly isomorphic. Remember this
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// non-speculatively.
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if (DstTy == SrcTy) {
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Entry = DstTy;
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return true;
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}
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// Okay, we have two types with identical kinds that we haven't seen before.
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// If this is an opaque struct type, special case it.
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if (StructType *SSTy = dyn_cast<StructType>(SrcTy)) {
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// Mapping an opaque type to any struct, just keep the dest struct.
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if (SSTy->isOpaque()) {
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Entry = DstTy;
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SpeculativeTypes.push_back(SrcTy);
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return true;
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}
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// Mapping a non-opaque source type to an opaque dest. If this is the first
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// type that we're mapping onto this destination type then we succeed. Keep
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// the dest, but fill it in later. If this is the second (different) type
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// that we're trying to map onto the same opaque type then we fail.
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if (cast<StructType>(DstTy)->isOpaque()) {
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// We can only map one source type onto the opaque destination type.
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if (!DstResolvedOpaqueTypes.insert(cast<StructType>(DstTy)).second)
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return false;
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SrcDefinitionsToResolve.push_back(SSTy);
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SpeculativeTypes.push_back(SrcTy);
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SpeculativeDstOpaqueTypes.push_back(cast<StructType>(DstTy));
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Entry = DstTy;
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return true;
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}
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}
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// If the number of subtypes disagree between the two types, then we fail.
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if (SrcTy->getNumContainedTypes() != DstTy->getNumContainedTypes())
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return false;
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// Fail if any of the extra properties (e.g. array size) of the type disagree.
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if (isa<IntegerType>(DstTy))
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return false; // bitwidth disagrees.
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if (PointerType *PT = dyn_cast<PointerType>(DstTy)) {
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if (PT->getAddressSpace() != cast<PointerType>(SrcTy)->getAddressSpace())
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return false;
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} else if (FunctionType *FT = dyn_cast<FunctionType>(DstTy)) {
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if (FT->isVarArg() != cast<FunctionType>(SrcTy)->isVarArg())
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return false;
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} else if (StructType *DSTy = dyn_cast<StructType>(DstTy)) {
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StructType *SSTy = cast<StructType>(SrcTy);
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if (DSTy->isLiteral() != SSTy->isLiteral() ||
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DSTy->isPacked() != SSTy->isPacked())
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return false;
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} else if (ArrayType *DATy = dyn_cast<ArrayType>(DstTy)) {
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if (DATy->getNumElements() != cast<ArrayType>(SrcTy)->getNumElements())
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return false;
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} else if (VectorType *DVTy = dyn_cast<VectorType>(DstTy)) {
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if (DVTy->getNumElements() != cast<VectorType>(SrcTy)->getNumElements())
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return false;
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}
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// Otherwise, we speculate that these two types will line up and recursively
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// check the subelements.
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Entry = DstTy;
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SpeculativeTypes.push_back(SrcTy);
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for (unsigned I = 0, E = SrcTy->getNumContainedTypes(); I != E; ++I)
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if (!areTypesIsomorphic(DstTy->getContainedType(I),
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SrcTy->getContainedType(I)))
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return false;
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// If everything seems to have lined up, then everything is great.
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return true;
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}
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void TypeMapTy::linkDefinedTypeBodies() {
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SmallVector<Type*, 16> Elements;
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for (StructType *SrcSTy : SrcDefinitionsToResolve) {
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StructType *DstSTy = cast<StructType>(MappedTypes[SrcSTy]);
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assert(DstSTy->isOpaque());
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// Map the body of the source type over to a new body for the dest type.
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Elements.resize(SrcSTy->getNumElements());
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for (unsigned I = 0, E = Elements.size(); I != E; ++I)
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Elements[I] = get(SrcSTy->getElementType(I));
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DstSTy->setBody(Elements, SrcSTy->isPacked());
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DstStructTypesSet.switchToNonOpaque(DstSTy);
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}
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SrcDefinitionsToResolve.clear();
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DstResolvedOpaqueTypes.clear();
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}
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void TypeMapTy::finishType(StructType *DTy, StructType *STy,
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ArrayRef<Type *> ETypes) {
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DTy->setBody(ETypes, STy->isPacked());
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// Steal STy's name.
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if (STy->hasName()) {
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SmallString<16> TmpName = STy->getName();
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STy->setName("");
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DTy->setName(TmpName);
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}
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DstStructTypesSet.addNonOpaque(DTy);
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}
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Type *TypeMapTy::get(Type *Ty) {
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SmallPtrSet<StructType *, 8> Visited;
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return get(Ty, Visited);
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}
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Type *TypeMapTy::get(Type *Ty, SmallPtrSet<StructType *, 8> &Visited) {
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// If we already have an entry for this type, return it.
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Type **Entry = &MappedTypes[Ty];
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if (*Entry)
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return *Entry;
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// These are types that LLVM itself will unique.
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bool IsUniqued = !isa<StructType>(Ty) || cast<StructType>(Ty)->isLiteral();
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#ifndef NDEBUG
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if (!IsUniqued) {
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for (auto &Pair : MappedTypes) {
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assert(!(Pair.first != Ty && Pair.second == Ty) &&
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"mapping to a source type");
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}
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}
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#endif
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if (!IsUniqued && !Visited.insert(cast<StructType>(Ty)).second) {
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StructType *DTy = StructType::create(Ty->getContext());
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return *Entry = DTy;
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}
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// If this is not a recursive type, then just map all of the elements and
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// then rebuild the type from inside out.
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SmallVector<Type *, 4> ElementTypes;
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// If there are no element types to map, then the type is itself. This is
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// true for the anonymous {} struct, things like 'float', integers, etc.
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if (Ty->getNumContainedTypes() == 0 && IsUniqued)
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return *Entry = Ty;
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// Remap all of the elements, keeping track of whether any of them change.
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bool AnyChange = false;
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ElementTypes.resize(Ty->getNumContainedTypes());
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for (unsigned I = 0, E = Ty->getNumContainedTypes(); I != E; ++I) {
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ElementTypes[I] = get(Ty->getContainedType(I), Visited);
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AnyChange |= ElementTypes[I] != Ty->getContainedType(I);
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}
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// If we found our type while recursively processing stuff, just use it.
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Entry = &MappedTypes[Ty];
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if (*Entry) {
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if (auto *DTy = dyn_cast<StructType>(*Entry)) {
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if (DTy->isOpaque()) {
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auto *STy = cast<StructType>(Ty);
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finishType(DTy, STy, ElementTypes);
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}
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}
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return *Entry;
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}
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// If all of the element types mapped directly over and the type is not
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// a nomed struct, then the type is usable as-is.
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if (!AnyChange && IsUniqued)
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return *Entry = Ty;
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// Otherwise, rebuild a modified type.
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switch (Ty->getTypeID()) {
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default:
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llvm_unreachable("unknown derived type to remap");
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case Type::ArrayTyID:
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return *Entry = ArrayType::get(ElementTypes[0],
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cast<ArrayType>(Ty)->getNumElements());
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case Type::VectorTyID:
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return *Entry = VectorType::get(ElementTypes[0],
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cast<VectorType>(Ty)->getNumElements());
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case Type::PointerTyID:
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return *Entry = PointerType::get(ElementTypes[0],
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cast<PointerType>(Ty)->getAddressSpace());
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case Type::FunctionTyID:
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return *Entry = FunctionType::get(ElementTypes[0],
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makeArrayRef(ElementTypes).slice(1),
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cast<FunctionType>(Ty)->isVarArg());
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case Type::StructTyID: {
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auto *STy = cast<StructType>(Ty);
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bool IsPacked = STy->isPacked();
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if (IsUniqued)
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return *Entry = StructType::get(Ty->getContext(), ElementTypes, IsPacked);
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// If the type is opaque, we can just use it directly.
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if (STy->isOpaque()) {
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DstStructTypesSet.addOpaque(STy);
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return *Entry = Ty;
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}
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if (StructType *OldT =
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DstStructTypesSet.findNonOpaque(ElementTypes, IsPacked)) {
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STy->setName("");
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return *Entry = OldT;
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}
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if (!AnyChange) {
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DstStructTypesSet.addNonOpaque(STy);
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return *Entry = Ty;
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}
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StructType *DTy = StructType::create(Ty->getContext());
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finishType(DTy, STy, ElementTypes);
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return *Entry = DTy;
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}
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}
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}
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//===----------------------------------------------------------------------===//
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// ModuleLinker implementation.
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//===----------------------------------------------------------------------===//
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namespace {
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class ModuleLinker;
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/// Creates prototypes for functions that are lazily linked on the fly. This
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/// speeds up linking for modules with many/ lazily linked functions of which
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/// few get used.
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class ValueMaterializerTy : public ValueMaterializer {
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TypeMapTy &TypeMap;
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Module *DstM;
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std::vector<GlobalValue *> &LazilyLinkGlobalValues;
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public:
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ValueMaterializerTy(TypeMapTy &TypeMap, Module *DstM,
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std::vector<GlobalValue *> &LazilyLinkGlobalValues)
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: ValueMaterializer(), TypeMap(TypeMap), DstM(DstM),
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LazilyLinkGlobalValues(LazilyLinkGlobalValues) {}
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Value *materializeValueFor(Value *V) override;
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};
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class LinkDiagnosticInfo : public DiagnosticInfo {
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const Twine &Msg;
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public:
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LinkDiagnosticInfo(DiagnosticSeverity Severity, const Twine &Msg);
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void print(DiagnosticPrinter &DP) const override;
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};
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LinkDiagnosticInfo::LinkDiagnosticInfo(DiagnosticSeverity Severity,
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const Twine &Msg)
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: DiagnosticInfo(DK_Linker, Severity), Msg(Msg) {}
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void LinkDiagnosticInfo::print(DiagnosticPrinter &DP) const { DP << Msg; }
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/// This is an implementation class for the LinkModules function, which is the
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/// entrypoint for this file.
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class ModuleLinker {
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Module *DstM, *SrcM;
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TypeMapTy TypeMap;
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ValueMaterializerTy ValMaterializer;
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/// Mapping of values from what they used to be in Src, to what they are now
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/// in DstM. ValueToValueMapTy is a ValueMap, which involves some overhead
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/// due to the use of Value handles which the Linker doesn't actually need,
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/// but this allows us to reuse the ValueMapper code.
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ValueToValueMapTy ValueMap;
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struct AppendingVarInfo {
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GlobalVariable *NewGV; // New aggregate global in dest module.
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const Constant *DstInit; // Old initializer from dest module.
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const Constant *SrcInit; // Old initializer from src module.
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};
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std::vector<AppendingVarInfo> AppendingVars;
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// Set of items not to link in from source.
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SmallPtrSet<const Value *, 16> DoNotLinkFromSource;
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// Vector of GlobalValues to lazily link in.
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std::vector<GlobalValue *> LazilyLinkGlobalValues;
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/// Functions that have replaced other functions.
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SmallPtrSet<const Function *, 16> OverridingFunctions;
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DiagnosticHandlerFunction DiagnosticHandler;
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/// For symbol clashes, prefer those from Src.
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bool OverrideFromSrc;
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public:
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ModuleLinker(Module *dstM, Linker::IdentifiedStructTypeSet &Set, Module *srcM,
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DiagnosticHandlerFunction DiagnosticHandler,
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bool OverrideFromSrc)
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: DstM(dstM), SrcM(srcM), TypeMap(Set),
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ValMaterializer(TypeMap, DstM, LazilyLinkGlobalValues),
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DiagnosticHandler(DiagnosticHandler), OverrideFromSrc(OverrideFromSrc) {
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}
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bool run();
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private:
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bool shouldLinkFromSource(bool &LinkFromSrc, const GlobalValue &Dest,
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const GlobalValue &Src);
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/// Helper method for setting a message and returning an error code.
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bool emitError(const Twine &Message) {
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DiagnosticHandler(LinkDiagnosticInfo(DS_Error, Message));
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return true;
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}
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void emitWarning(const Twine &Message) {
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DiagnosticHandler(LinkDiagnosticInfo(DS_Warning, Message));
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}
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bool getComdatLeader(Module *M, StringRef ComdatName,
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const GlobalVariable *&GVar);
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bool computeResultingSelectionKind(StringRef ComdatName,
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Comdat::SelectionKind Src,
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Comdat::SelectionKind Dst,
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Comdat::SelectionKind &Result,
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bool &LinkFromSrc);
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std::map<const Comdat *, std::pair<Comdat::SelectionKind, bool>>
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ComdatsChosen;
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bool getComdatResult(const Comdat *SrcC, Comdat::SelectionKind &SK,
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bool &LinkFromSrc);
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/// Given a global in the source module, return the global in the
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/// destination module that is being linked to, if any.
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GlobalValue *getLinkedToGlobal(const GlobalValue *SrcGV) {
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// If the source has no name it can't link. If it has local linkage,
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// there is no name match-up going on.
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if (!SrcGV->hasName() || SrcGV->hasLocalLinkage())
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return nullptr;
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// Otherwise see if we have a match in the destination module's symtab.
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GlobalValue *DGV = DstM->getNamedValue(SrcGV->getName());
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if (!DGV)
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return nullptr;
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// If we found a global with the same name in the dest module, but it has
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// internal linkage, we are really not doing any linkage here.
|
|
if (DGV->hasLocalLinkage())
|
|
return nullptr;
|
|
|
|
// Otherwise, we do in fact link to the destination global.
|
|
return DGV;
|
|
}
|
|
|
|
void computeTypeMapping();
|
|
|
|
void upgradeMismatchedGlobalArray(StringRef Name);
|
|
void upgradeMismatchedGlobals();
|
|
|
|
bool linkAppendingVarProto(GlobalVariable *DstGV,
|
|
const GlobalVariable *SrcGV);
|
|
|
|
bool linkGlobalValueProto(GlobalValue *GV);
|
|
bool linkModuleFlagsMetadata();
|
|
|
|
void linkAppendingVarInit(const AppendingVarInfo &AVI);
|
|
|
|
void linkGlobalInit(GlobalVariable &Dst, GlobalVariable &Src);
|
|
bool linkFunctionBody(Function &Dst, Function &Src);
|
|
void linkAliasBody(GlobalAlias &Dst, GlobalAlias &Src);
|
|
bool linkGlobalValueBody(GlobalValue &Src);
|
|
|
|
void linkNamedMDNodes();
|
|
void stripReplacedSubprograms();
|
|
};
|
|
}
|
|
|
|
/// The LLVM SymbolTable class autorenames globals that conflict in the symbol
|
|
/// table. This is good for all clients except for us. Go through the trouble
|
|
/// to force this back.
|
|
static void forceRenaming(GlobalValue *GV, StringRef Name) {
|
|
// If the global doesn't force its name or if it already has the right name,
|
|
// there is nothing for us to do.
|
|
if (GV->hasLocalLinkage() || GV->getName() == Name)
|
|
return;
|
|
|
|
Module *M = GV->getParent();
|
|
|
|
// If there is a conflict, rename the conflict.
|
|
if (GlobalValue *ConflictGV = M->getNamedValue(Name)) {
|
|
GV->takeName(ConflictGV);
|
|
ConflictGV->setName(Name); // This will cause ConflictGV to get renamed
|
|
assert(ConflictGV->getName() != Name && "forceRenaming didn't work");
|
|
} else {
|
|
GV->setName(Name); // Force the name back
|
|
}
|
|
}
|
|
|
|
/// copy additional attributes (those not needed to construct a GlobalValue)
|
|
/// from the SrcGV to the DestGV.
|
|
static void copyGVAttributes(GlobalValue *DestGV, const GlobalValue *SrcGV) {
|
|
DestGV->copyAttributesFrom(SrcGV);
|
|
forceRenaming(DestGV, SrcGV->getName());
|
|
}
|
|
|
|
static bool isLessConstraining(GlobalValue::VisibilityTypes a,
|
|
GlobalValue::VisibilityTypes b) {
|
|
if (a == GlobalValue::HiddenVisibility)
|
|
return false;
|
|
if (b == GlobalValue::HiddenVisibility)
|
|
return true;
|
|
if (a == GlobalValue::ProtectedVisibility)
|
|
return false;
|
|
if (b == GlobalValue::ProtectedVisibility)
|
|
return true;
|
|
return false;
|
|
}
|
|
|
|
/// Loop through the global variables in the src module and merge them into the
|
|
/// dest module.
|
|
static GlobalVariable *copyGlobalVariableProto(TypeMapTy &TypeMap, Module &DstM,
|
|
const GlobalVariable *SGVar) {
|
|
// No linking to be performed or linking from the source: simply create an
|
|
// identical version of the symbol over in the dest module... the
|
|
// initializer will be filled in later by LinkGlobalInits.
|
|
GlobalVariable *NewDGV = new GlobalVariable(
|
|
DstM, TypeMap.get(SGVar->getType()->getElementType()),
|
|
SGVar->isConstant(), SGVar->getLinkage(), /*init*/ nullptr,
|
|
SGVar->getName(), /*insertbefore*/ nullptr, SGVar->getThreadLocalMode(),
|
|
SGVar->getType()->getAddressSpace());
|
|
|
|
return NewDGV;
|
|
}
|
|
|
|
/// Link the function in the source module into the destination module if
|
|
/// needed, setting up mapping information.
|
|
static Function *copyFunctionProto(TypeMapTy &TypeMap, Module &DstM,
|
|
const Function *SF) {
|
|
// If there is no linkage to be performed or we are linking from the source,
|
|
// bring SF over.
|
|
return Function::Create(TypeMap.get(SF->getFunctionType()), SF->getLinkage(),
|
|
SF->getName(), &DstM);
|
|
}
|
|
|
|
/// Set up prototypes for any aliases that come over from the source module.
|
|
static GlobalAlias *copyGlobalAliasProto(TypeMapTy &TypeMap, Module &DstM,
|
|
const GlobalAlias *SGA) {
|
|
// If there is no linkage to be performed or we're linking from the source,
|
|
// bring over SGA.
|
|
auto *PTy = cast<PointerType>(TypeMap.get(SGA->getType()));
|
|
return GlobalAlias::create(PTy, SGA->getLinkage(), SGA->getName(), &DstM);
|
|
}
|
|
|
|
static GlobalValue *copyGlobalValueProto(TypeMapTy &TypeMap, Module &DstM,
|
|
const GlobalValue *SGV) {
|
|
GlobalValue *NewGV;
|
|
if (auto *SGVar = dyn_cast<GlobalVariable>(SGV))
|
|
NewGV = copyGlobalVariableProto(TypeMap, DstM, SGVar);
|
|
else if (auto *SF = dyn_cast<Function>(SGV))
|
|
NewGV = copyFunctionProto(TypeMap, DstM, SF);
|
|
else
|
|
NewGV = copyGlobalAliasProto(TypeMap, DstM, cast<GlobalAlias>(SGV));
|
|
copyGVAttributes(NewGV, SGV);
|
|
return NewGV;
|
|
}
|
|
|
|
Value *ValueMaterializerTy::materializeValueFor(Value *V) {
|
|
auto *SGV = dyn_cast<GlobalValue>(V);
|
|
if (!SGV)
|
|
return nullptr;
|
|
|
|
GlobalValue *DGV = copyGlobalValueProto(TypeMap, *DstM, SGV);
|
|
|
|
if (Comdat *SC = SGV->getComdat()) {
|
|
if (auto *DGO = dyn_cast<GlobalObject>(DGV)) {
|
|
Comdat *DC = DstM->getOrInsertComdat(SC->getName());
|
|
DGO->setComdat(DC);
|
|
}
|
|
}
|
|
|
|
LazilyLinkGlobalValues.push_back(SGV);
|
|
return DGV;
|
|
}
|
|
|
|
bool ModuleLinker::getComdatLeader(Module *M, StringRef ComdatName,
|
|
const GlobalVariable *&GVar) {
|
|
const GlobalValue *GVal = M->getNamedValue(ComdatName);
|
|
if (const auto *GA = dyn_cast_or_null<GlobalAlias>(GVal)) {
|
|
GVal = GA->getBaseObject();
|
|
if (!GVal)
|
|
// We cannot resolve the size of the aliasee yet.
|
|
return emitError("Linking COMDATs named '" + ComdatName +
|
|
"': COMDAT key involves incomputable alias size.");
|
|
}
|
|
|
|
GVar = dyn_cast_or_null<GlobalVariable>(GVal);
|
|
if (!GVar)
|
|
return emitError(
|
|
"Linking COMDATs named '" + ComdatName +
|
|
"': GlobalVariable required for data dependent selection!");
|
|
|
|
return false;
|
|
}
|
|
|
|
bool ModuleLinker::computeResultingSelectionKind(StringRef ComdatName,
|
|
Comdat::SelectionKind Src,
|
|
Comdat::SelectionKind Dst,
|
|
Comdat::SelectionKind &Result,
|
|
bool &LinkFromSrc) {
|
|
// The ability to mix Comdat::SelectionKind::Any with
|
|
// Comdat::SelectionKind::Largest is a behavior that comes from COFF.
|
|
bool DstAnyOrLargest = Dst == Comdat::SelectionKind::Any ||
|
|
Dst == Comdat::SelectionKind::Largest;
|
|
bool SrcAnyOrLargest = Src == Comdat::SelectionKind::Any ||
|
|
Src == Comdat::SelectionKind::Largest;
|
|
if (DstAnyOrLargest && SrcAnyOrLargest) {
|
|
if (Dst == Comdat::SelectionKind::Largest ||
|
|
Src == Comdat::SelectionKind::Largest)
|
|
Result = Comdat::SelectionKind::Largest;
|
|
else
|
|
Result = Comdat::SelectionKind::Any;
|
|
} else if (Src == Dst) {
|
|
Result = Dst;
|
|
} else {
|
|
return emitError("Linking COMDATs named '" + ComdatName +
|
|
"': invalid selection kinds!");
|
|
}
|
|
|
|
switch (Result) {
|
|
case Comdat::SelectionKind::Any:
|
|
// Go with Dst.
|
|
LinkFromSrc = false;
|
|
break;
|
|
case Comdat::SelectionKind::NoDuplicates:
|
|
return emitError("Linking COMDATs named '" + ComdatName +
|
|
"': noduplicates has been violated!");
|
|
case Comdat::SelectionKind::ExactMatch:
|
|
case Comdat::SelectionKind::Largest:
|
|
case Comdat::SelectionKind::SameSize: {
|
|
const GlobalVariable *DstGV;
|
|
const GlobalVariable *SrcGV;
|
|
if (getComdatLeader(DstM, ComdatName, DstGV) ||
|
|
getComdatLeader(SrcM, ComdatName, SrcGV))
|
|
return true;
|
|
|
|
const DataLayout &DstDL = DstM->getDataLayout();
|
|
const DataLayout &SrcDL = SrcM->getDataLayout();
|
|
uint64_t DstSize =
|
|
DstDL.getTypeAllocSize(DstGV->getType()->getPointerElementType());
|
|
uint64_t SrcSize =
|
|
SrcDL.getTypeAllocSize(SrcGV->getType()->getPointerElementType());
|
|
if (Result == Comdat::SelectionKind::ExactMatch) {
|
|
if (SrcGV->getInitializer() != DstGV->getInitializer())
|
|
return emitError("Linking COMDATs named '" + ComdatName +
|
|
"': ExactMatch violated!");
|
|
LinkFromSrc = false;
|
|
} else if (Result == Comdat::SelectionKind::Largest) {
|
|
LinkFromSrc = SrcSize > DstSize;
|
|
} else if (Result == Comdat::SelectionKind::SameSize) {
|
|
if (SrcSize != DstSize)
|
|
return emitError("Linking COMDATs named '" + ComdatName +
|
|
"': SameSize violated!");
|
|
LinkFromSrc = false;
|
|
} else {
|
|
llvm_unreachable("unknown selection kind");
|
|
}
|
|
break;
|
|
}
|
|
}
|
|
|
|
return false;
|
|
}
|
|
|
|
bool ModuleLinker::getComdatResult(const Comdat *SrcC,
|
|
Comdat::SelectionKind &Result,
|
|
bool &LinkFromSrc) {
|
|
Comdat::SelectionKind SSK = SrcC->getSelectionKind();
|
|
StringRef ComdatName = SrcC->getName();
|
|
Module::ComdatSymTabType &ComdatSymTab = DstM->getComdatSymbolTable();
|
|
Module::ComdatSymTabType::iterator DstCI = ComdatSymTab.find(ComdatName);
|
|
|
|
if (DstCI == ComdatSymTab.end()) {
|
|
// Use the comdat if it is only available in one of the modules.
|
|
LinkFromSrc = true;
|
|
Result = SSK;
|
|
return false;
|
|
}
|
|
|
|
const Comdat *DstC = &DstCI->second;
|
|
Comdat::SelectionKind DSK = DstC->getSelectionKind();
|
|
return computeResultingSelectionKind(ComdatName, SSK, DSK, Result,
|
|
LinkFromSrc);
|
|
}
|
|
|
|
bool ModuleLinker::shouldLinkFromSource(bool &LinkFromSrc,
|
|
const GlobalValue &Dest,
|
|
const GlobalValue &Src) {
|
|
// Should we unconditionally use the Src?
|
|
if (OverrideFromSrc) {
|
|
LinkFromSrc = true;
|
|
return false;
|
|
}
|
|
|
|
// We always have to add Src if it has appending linkage.
|
|
if (Src.hasAppendingLinkage()) {
|
|
LinkFromSrc = true;
|
|
return false;
|
|
}
|
|
|
|
bool SrcIsDeclaration = Src.isDeclarationForLinker();
|
|
bool DestIsDeclaration = Dest.isDeclarationForLinker();
|
|
|
|
if (SrcIsDeclaration) {
|
|
// If Src is external or if both Src & Dest are external.. Just link the
|
|
// external globals, we aren't adding anything.
|
|
if (Src.hasDLLImportStorageClass()) {
|
|
// If one of GVs is marked as DLLImport, result should be dllimport'ed.
|
|
LinkFromSrc = DestIsDeclaration;
|
|
return false;
|
|
}
|
|
// If the Dest is weak, use the source linkage.
|
|
LinkFromSrc = Dest.hasExternalWeakLinkage();
|
|
return false;
|
|
}
|
|
|
|
if (DestIsDeclaration) {
|
|
// If Dest is external but Src is not:
|
|
LinkFromSrc = true;
|
|
return false;
|
|
}
|
|
|
|
if (Src.hasCommonLinkage()) {
|
|
if (Dest.hasLinkOnceLinkage() || Dest.hasWeakLinkage()) {
|
|
LinkFromSrc = true;
|
|
return false;
|
|
}
|
|
|
|
if (!Dest.hasCommonLinkage()) {
|
|
LinkFromSrc = false;
|
|
return false;
|
|
}
|
|
|
|
const DataLayout &DL = Dest.getParent()->getDataLayout();
|
|
uint64_t DestSize = DL.getTypeAllocSize(Dest.getType()->getElementType());
|
|
uint64_t SrcSize = DL.getTypeAllocSize(Src.getType()->getElementType());
|
|
LinkFromSrc = SrcSize > DestSize;
|
|
return false;
|
|
}
|
|
|
|
if (Src.isWeakForLinker()) {
|
|
assert(!Dest.hasExternalWeakLinkage());
|
|
assert(!Dest.hasAvailableExternallyLinkage());
|
|
|
|
if (Dest.hasLinkOnceLinkage() && Src.hasWeakLinkage()) {
|
|
LinkFromSrc = true;
|
|
return false;
|
|
}
|
|
|
|
LinkFromSrc = false;
|
|
return false;
|
|
}
|
|
|
|
if (Dest.isWeakForLinker()) {
|
|
assert(Src.hasExternalLinkage());
|
|
LinkFromSrc = true;
|
|
return false;
|
|
}
|
|
|
|
assert(!Src.hasExternalWeakLinkage());
|
|
assert(!Dest.hasExternalWeakLinkage());
|
|
assert(Dest.hasExternalLinkage() && Src.hasExternalLinkage() &&
|
|
"Unexpected linkage type!");
|
|
return emitError("Linking globals named '" + Src.getName() +
|
|
"': symbol multiply defined!");
|
|
}
|
|
|
|
/// Loop over all of the linked values to compute type mappings. For example,
|
|
/// if we link "extern Foo *x" and "Foo *x = NULL", then we have two struct
|
|
/// types 'Foo' but one got renamed when the module was loaded into the same
|
|
/// LLVMContext.
|
|
void ModuleLinker::computeTypeMapping() {
|
|
for (GlobalValue &SGV : SrcM->globals()) {
|
|
GlobalValue *DGV = getLinkedToGlobal(&SGV);
|
|
if (!DGV)
|
|
continue;
|
|
|
|
if (!DGV->hasAppendingLinkage() || !SGV.hasAppendingLinkage()) {
|
|
TypeMap.addTypeMapping(DGV->getType(), SGV.getType());
|
|
continue;
|
|
}
|
|
|
|
// Unify the element type of appending arrays.
|
|
ArrayType *DAT = cast<ArrayType>(DGV->getType()->getElementType());
|
|
ArrayType *SAT = cast<ArrayType>(SGV.getType()->getElementType());
|
|
TypeMap.addTypeMapping(DAT->getElementType(), SAT->getElementType());
|
|
}
|
|
|
|
for (GlobalValue &SGV : *SrcM) {
|
|
if (GlobalValue *DGV = getLinkedToGlobal(&SGV))
|
|
TypeMap.addTypeMapping(DGV->getType(), SGV.getType());
|
|
}
|
|
|
|
for (GlobalValue &SGV : SrcM->aliases()) {
|
|
if (GlobalValue *DGV = getLinkedToGlobal(&SGV))
|
|
TypeMap.addTypeMapping(DGV->getType(), SGV.getType());
|
|
}
|
|
|
|
// Incorporate types by name, scanning all the types in the source module.
|
|
// At this point, the destination module may have a type "%foo = { i32 }" for
|
|
// example. When the source module got loaded into the same LLVMContext, if
|
|
// it had the same type, it would have been renamed to "%foo.42 = { i32 }".
|
|
std::vector<StructType *> Types = SrcM->getIdentifiedStructTypes();
|
|
for (StructType *ST : Types) {
|
|
if (!ST->hasName())
|
|
continue;
|
|
|
|
// Check to see if there is a dot in the name followed by a digit.
|
|
size_t DotPos = ST->getName().rfind('.');
|
|
if (DotPos == 0 || DotPos == StringRef::npos ||
|
|
ST->getName().back() == '.' ||
|
|
!isdigit(static_cast<unsigned char>(ST->getName()[DotPos + 1])))
|
|
continue;
|
|
|
|
// Check to see if the destination module has a struct with the prefix name.
|
|
StructType *DST = DstM->getTypeByName(ST->getName().substr(0, DotPos));
|
|
if (!DST)
|
|
continue;
|
|
|
|
// Don't use it if this actually came from the source module. They're in
|
|
// the same LLVMContext after all. Also don't use it unless the type is
|
|
// actually used in the destination module. This can happen in situations
|
|
// like this:
|
|
//
|
|
// Module A Module B
|
|
// -------- --------
|
|
// %Z = type { %A } %B = type { %C.1 }
|
|
// %A = type { %B.1, [7 x i8] } %C.1 = type { i8* }
|
|
// %B.1 = type { %C } %A.2 = type { %B.3, [5 x i8] }
|
|
// %C = type { i8* } %B.3 = type { %C.1 }
|
|
//
|
|
// When we link Module B with Module A, the '%B' in Module B is
|
|
// used. However, that would then use '%C.1'. But when we process '%C.1',
|
|
// we prefer to take the '%C' version. So we are then left with both
|
|
// '%C.1' and '%C' being used for the same types. This leads to some
|
|
// variables using one type and some using the other.
|
|
if (TypeMap.DstStructTypesSet.hasType(DST))
|
|
TypeMap.addTypeMapping(DST, ST);
|
|
}
|
|
|
|
// Now that we have discovered all of the type equivalences, get a body for
|
|
// any 'opaque' types in the dest module that are now resolved.
|
|
TypeMap.linkDefinedTypeBodies();
|
|
}
|
|
|
|
static void upgradeGlobalArray(GlobalVariable *GV) {
|
|
ArrayType *ATy = cast<ArrayType>(GV->getType()->getElementType());
|
|
StructType *OldTy = cast<StructType>(ATy->getElementType());
|
|
assert(OldTy->getNumElements() == 2 && "Expected to upgrade from 2 elements");
|
|
|
|
// Get the upgraded 3 element type.
|
|
PointerType *VoidPtrTy = Type::getInt8Ty(GV->getContext())->getPointerTo();
|
|
Type *Tys[3] = {OldTy->getElementType(0), OldTy->getElementType(1),
|
|
VoidPtrTy};
|
|
StructType *NewTy = StructType::get(GV->getContext(), Tys, false);
|
|
|
|
// Build new constants with a null third field filled in.
|
|
Constant *OldInitC = GV->getInitializer();
|
|
ConstantArray *OldInit = dyn_cast<ConstantArray>(OldInitC);
|
|
if (!OldInit && !isa<ConstantAggregateZero>(OldInitC))
|
|
// Invalid initializer; give up.
|
|
return;
|
|
std::vector<Constant *> Initializers;
|
|
if (OldInit && OldInit->getNumOperands()) {
|
|
Value *Null = Constant::getNullValue(VoidPtrTy);
|
|
for (Use &U : OldInit->operands()) {
|
|
ConstantStruct *Init = cast<ConstantStruct>(U.get());
|
|
Initializers.push_back(ConstantStruct::get(
|
|
NewTy, Init->getOperand(0), Init->getOperand(1), Null, nullptr));
|
|
}
|
|
}
|
|
assert(Initializers.size() == ATy->getNumElements() &&
|
|
"Failed to copy all array elements");
|
|
|
|
// Replace the old GV with a new one.
|
|
ATy = ArrayType::get(NewTy, Initializers.size());
|
|
Constant *NewInit = ConstantArray::get(ATy, Initializers);
|
|
GlobalVariable *NewGV = new GlobalVariable(
|
|
*GV->getParent(), ATy, GV->isConstant(), GV->getLinkage(), NewInit, "",
|
|
GV, GV->getThreadLocalMode(), GV->getType()->getAddressSpace(),
|
|
GV->isExternallyInitialized());
|
|
NewGV->copyAttributesFrom(GV);
|
|
NewGV->takeName(GV);
|
|
assert(GV->use_empty() && "program cannot use initializer list");
|
|
GV->eraseFromParent();
|
|
}
|
|
|
|
void ModuleLinker::upgradeMismatchedGlobalArray(StringRef Name) {
|
|
// Look for the global arrays.
|
|
auto *DstGV = dyn_cast_or_null<GlobalVariable>(DstM->getNamedValue(Name));
|
|
if (!DstGV)
|
|
return;
|
|
auto *SrcGV = dyn_cast_or_null<GlobalVariable>(SrcM->getNamedValue(Name));
|
|
if (!SrcGV)
|
|
return;
|
|
|
|
// Check if the types already match.
|
|
auto *DstTy = cast<ArrayType>(DstGV->getType()->getElementType());
|
|
auto *SrcTy =
|
|
cast<ArrayType>(TypeMap.get(SrcGV->getType()->getElementType()));
|
|
if (DstTy == SrcTy)
|
|
return;
|
|
|
|
// Grab the element types. We can only upgrade an array of a two-field
|
|
// struct. Only bother if the other one has three-fields.
|
|
auto *DstEltTy = cast<StructType>(DstTy->getElementType());
|
|
auto *SrcEltTy = cast<StructType>(SrcTy->getElementType());
|
|
if (DstEltTy->getNumElements() == 2 && SrcEltTy->getNumElements() == 3) {
|
|
upgradeGlobalArray(DstGV);
|
|
return;
|
|
}
|
|
if (DstEltTy->getNumElements() == 3 && SrcEltTy->getNumElements() == 2)
|
|
upgradeGlobalArray(SrcGV);
|
|
|
|
// We can't upgrade any other differences.
|
|
}
|
|
|
|
void ModuleLinker::upgradeMismatchedGlobals() {
|
|
upgradeMismatchedGlobalArray("llvm.global_ctors");
|
|
upgradeMismatchedGlobalArray("llvm.global_dtors");
|
|
}
|
|
|
|
/// If there were any appending global variables, link them together now.
|
|
/// Return true on error.
|
|
bool ModuleLinker::linkAppendingVarProto(GlobalVariable *DstGV,
|
|
const GlobalVariable *SrcGV) {
|
|
|
|
if (!SrcGV->hasAppendingLinkage() || !DstGV->hasAppendingLinkage())
|
|
return emitError("Linking globals named '" + SrcGV->getName() +
|
|
"': can only link appending global with another appending global!");
|
|
|
|
ArrayType *DstTy = cast<ArrayType>(DstGV->getType()->getElementType());
|
|
ArrayType *SrcTy =
|
|
cast<ArrayType>(TypeMap.get(SrcGV->getType()->getElementType()));
|
|
Type *EltTy = DstTy->getElementType();
|
|
|
|
// Check to see that they two arrays agree on type.
|
|
if (EltTy != SrcTy->getElementType())
|
|
return emitError("Appending variables with different element types!");
|
|
if (DstGV->isConstant() != SrcGV->isConstant())
|
|
return emitError("Appending variables linked with different const'ness!");
|
|
|
|
if (DstGV->getAlignment() != SrcGV->getAlignment())
|
|
return emitError(
|
|
"Appending variables with different alignment need to be linked!");
|
|
|
|
if (DstGV->getVisibility() != SrcGV->getVisibility())
|
|
return emitError(
|
|
"Appending variables with different visibility need to be linked!");
|
|
|
|
if (DstGV->hasUnnamedAddr() != SrcGV->hasUnnamedAddr())
|
|
return emitError(
|
|
"Appending variables with different unnamed_addr need to be linked!");
|
|
|
|
if (StringRef(DstGV->getSection()) != SrcGV->getSection())
|
|
return emitError(
|
|
"Appending variables with different section name need to be linked!");
|
|
|
|
uint64_t NewSize = DstTy->getNumElements() + SrcTy->getNumElements();
|
|
ArrayType *NewType = ArrayType::get(EltTy, NewSize);
|
|
|
|
// Create the new global variable.
|
|
GlobalVariable *NG =
|
|
new GlobalVariable(*DstGV->getParent(), NewType, SrcGV->isConstant(),
|
|
DstGV->getLinkage(), /*init*/nullptr, /*name*/"", DstGV,
|
|
DstGV->getThreadLocalMode(),
|
|
DstGV->getType()->getAddressSpace());
|
|
|
|
// Propagate alignment, visibility and section info.
|
|
copyGVAttributes(NG, DstGV);
|
|
|
|
AppendingVarInfo AVI;
|
|
AVI.NewGV = NG;
|
|
AVI.DstInit = DstGV->getInitializer();
|
|
AVI.SrcInit = SrcGV->getInitializer();
|
|
AppendingVars.push_back(AVI);
|
|
|
|
// Replace any uses of the two global variables with uses of the new
|
|
// global.
|
|
ValueMap[SrcGV] = ConstantExpr::getBitCast(NG, TypeMap.get(SrcGV->getType()));
|
|
|
|
DstGV->replaceAllUsesWith(ConstantExpr::getBitCast(NG, DstGV->getType()));
|
|
DstGV->eraseFromParent();
|
|
|
|
// Track the source variable so we don't try to link it.
|
|
DoNotLinkFromSource.insert(SrcGV);
|
|
|
|
return false;
|
|
}
|
|
|
|
bool ModuleLinker::linkGlobalValueProto(GlobalValue *SGV) {
|
|
GlobalValue *DGV = getLinkedToGlobal(SGV);
|
|
|
|
// Handle the ultra special appending linkage case first.
|
|
if (DGV && DGV->hasAppendingLinkage())
|
|
return linkAppendingVarProto(cast<GlobalVariable>(DGV),
|
|
cast<GlobalVariable>(SGV));
|
|
|
|
bool LinkFromSrc = true;
|
|
Comdat *C = nullptr;
|
|
GlobalValue::VisibilityTypes Visibility = SGV->getVisibility();
|
|
bool HasUnnamedAddr = SGV->hasUnnamedAddr();
|
|
|
|
if (const Comdat *SC = SGV->getComdat()) {
|
|
Comdat::SelectionKind SK;
|
|
std::tie(SK, LinkFromSrc) = ComdatsChosen[SC];
|
|
C = DstM->getOrInsertComdat(SC->getName());
|
|
C->setSelectionKind(SK);
|
|
} else if (DGV) {
|
|
if (shouldLinkFromSource(LinkFromSrc, *DGV, *SGV))
|
|
return true;
|
|
}
|
|
|
|
if (!LinkFromSrc) {
|
|
// Track the source global so that we don't attempt to copy it over when
|
|
// processing global initializers.
|
|
DoNotLinkFromSource.insert(SGV);
|
|
|
|
if (DGV)
|
|
// Make sure to remember this mapping.
|
|
ValueMap[SGV] =
|
|
ConstantExpr::getBitCast(DGV, TypeMap.get(SGV->getType()));
|
|
}
|
|
|
|
if (DGV) {
|
|
Visibility = isLessConstraining(Visibility, DGV->getVisibility())
|
|
? DGV->getVisibility()
|
|
: Visibility;
|
|
HasUnnamedAddr = HasUnnamedAddr && DGV->hasUnnamedAddr();
|
|
}
|
|
|
|
if (!LinkFromSrc && !DGV)
|
|
return false;
|
|
|
|
GlobalValue *NewGV;
|
|
if (!LinkFromSrc) {
|
|
NewGV = DGV;
|
|
} else {
|
|
// If the GV is to be lazily linked, don't create it just yet.
|
|
// The ValueMaterializerTy will deal with creating it if it's used.
|
|
if (!DGV && !OverrideFromSrc &&
|
|
(SGV->hasLocalLinkage() || SGV->hasLinkOnceLinkage() ||
|
|
SGV->hasAvailableExternallyLinkage())) {
|
|
DoNotLinkFromSource.insert(SGV);
|
|
return false;
|
|
}
|
|
|
|
NewGV = copyGlobalValueProto(TypeMap, *DstM, SGV);
|
|
|
|
if (DGV && isa<Function>(DGV))
|
|
if (auto *NewF = dyn_cast<Function>(NewGV))
|
|
OverridingFunctions.insert(NewF);
|
|
}
|
|
|
|
NewGV->setUnnamedAddr(HasUnnamedAddr);
|
|
NewGV->setVisibility(Visibility);
|
|
|
|
if (auto *NewGO = dyn_cast<GlobalObject>(NewGV)) {
|
|
if (C)
|
|
NewGO->setComdat(C);
|
|
|
|
if (DGV && DGV->hasCommonLinkage() && SGV->hasCommonLinkage())
|
|
NewGO->setAlignment(std::max(DGV->getAlignment(), SGV->getAlignment()));
|
|
}
|
|
|
|
if (auto *NewGVar = dyn_cast<GlobalVariable>(NewGV)) {
|
|
auto *DGVar = dyn_cast_or_null<GlobalVariable>(DGV);
|
|
auto *SGVar = dyn_cast<GlobalVariable>(SGV);
|
|
if (DGVar && SGVar && DGVar->isDeclaration() && SGVar->isDeclaration() &&
|
|
(!DGVar->isConstant() || !SGVar->isConstant()))
|
|
NewGVar->setConstant(false);
|
|
}
|
|
|
|
// Make sure to remember this mapping.
|
|
if (NewGV != DGV) {
|
|
if (DGV) {
|
|
DGV->replaceAllUsesWith(ConstantExpr::getBitCast(NewGV, DGV->getType()));
|
|
DGV->eraseFromParent();
|
|
}
|
|
ValueMap[SGV] = NewGV;
|
|
}
|
|
|
|
return false;
|
|
}
|
|
|
|
static void getArrayElements(const Constant *C,
|
|
SmallVectorImpl<Constant *> &Dest) {
|
|
unsigned NumElements = cast<ArrayType>(C->getType())->getNumElements();
|
|
|
|
for (unsigned i = 0; i != NumElements; ++i)
|
|
Dest.push_back(C->getAggregateElement(i));
|
|
}
|
|
|
|
void ModuleLinker::linkAppendingVarInit(const AppendingVarInfo &AVI) {
|
|
// Merge the initializer.
|
|
SmallVector<Constant *, 16> DstElements;
|
|
getArrayElements(AVI.DstInit, DstElements);
|
|
|
|
SmallVector<Constant *, 16> SrcElements;
|
|
getArrayElements(AVI.SrcInit, SrcElements);
|
|
|
|
ArrayType *NewType = cast<ArrayType>(AVI.NewGV->getType()->getElementType());
|
|
|
|
StringRef Name = AVI.NewGV->getName();
|
|
bool IsNewStructor =
|
|
(Name == "llvm.global_ctors" || Name == "llvm.global_dtors") &&
|
|
cast<StructType>(NewType->getElementType())->getNumElements() == 3;
|
|
|
|
for (auto *V : SrcElements) {
|
|
if (IsNewStructor) {
|
|
Constant *Key = V->getAggregateElement(2);
|
|
if (DoNotLinkFromSource.count(Key))
|
|
continue;
|
|
}
|
|
DstElements.push_back(
|
|
MapValue(V, ValueMap, RF_None, &TypeMap, &ValMaterializer));
|
|
}
|
|
if (IsNewStructor) {
|
|
NewType = ArrayType::get(NewType->getElementType(), DstElements.size());
|
|
AVI.NewGV->mutateType(PointerType::get(NewType, 0));
|
|
}
|
|
|
|
AVI.NewGV->setInitializer(ConstantArray::get(NewType, DstElements));
|
|
}
|
|
|
|
/// Update the initializers in the Dest module now that all globals that may be
|
|
/// referenced are in Dest.
|
|
void ModuleLinker::linkGlobalInit(GlobalVariable &Dst, GlobalVariable &Src) {
|
|
// Figure out what the initializer looks like in the dest module.
|
|
Dst.setInitializer(MapValue(Src.getInitializer(), ValueMap, RF_None, &TypeMap,
|
|
&ValMaterializer));
|
|
}
|
|
|
|
/// Copy the source function over into the dest function and fix up references
|
|
/// to values. At this point we know that Dest is an external function, and
|
|
/// that Src is not.
|
|
bool ModuleLinker::linkFunctionBody(Function &Dst, Function &Src) {
|
|
assert(Dst.isDeclaration() && !Src.isDeclaration());
|
|
|
|
// Materialize if needed.
|
|
if (std::error_code EC = Src.materialize())
|
|
return emitError(EC.message());
|
|
|
|
// Link in the prefix data.
|
|
if (Src.hasPrefixData())
|
|
Dst.setPrefixData(MapValue(Src.getPrefixData(), ValueMap, RF_None, &TypeMap,
|
|
&ValMaterializer));
|
|
|
|
// Link in the prologue data.
|
|
if (Src.hasPrologueData())
|
|
Dst.setPrologueData(MapValue(Src.getPrologueData(), ValueMap, RF_None,
|
|
&TypeMap, &ValMaterializer));
|
|
|
|
// Link in the personality function.
|
|
if (Src.hasPersonalityFn())
|
|
Dst.setPersonalityFn(MapValue(Src.getPersonalityFn(), ValueMap, RF_None,
|
|
&TypeMap, &ValMaterializer));
|
|
|
|
// Go through and convert function arguments over, remembering the mapping.
|
|
Function::arg_iterator DI = Dst.arg_begin();
|
|
for (Argument &Arg : Src.args()) {
|
|
DI->setName(Arg.getName()); // Copy the name over.
|
|
|
|
// Add a mapping to our mapping.
|
|
ValueMap[&Arg] = DI;
|
|
++DI;
|
|
}
|
|
|
|
// Copy over the metadata attachments.
|
|
SmallVector<std::pair<unsigned, MDNode *>, 8> MDs;
|
|
Src.getAllMetadata(MDs);
|
|
for (const auto &I : MDs)
|
|
Dst.setMetadata(I.first, MapMetadata(I.second, ValueMap, RF_None, &TypeMap,
|
|
&ValMaterializer));
|
|
|
|
// Splice the body of the source function into the dest function.
|
|
Dst.getBasicBlockList().splice(Dst.end(), Src.getBasicBlockList());
|
|
|
|
// At this point, all of the instructions and values of the function are now
|
|
// copied over. The only problem is that they are still referencing values in
|
|
// the Source function as operands. Loop through all of the operands of the
|
|
// functions and patch them up to point to the local versions.
|
|
for (BasicBlock &BB : Dst)
|
|
for (Instruction &I : BB)
|
|
RemapInstruction(&I, ValueMap, RF_IgnoreMissingEntries, &TypeMap,
|
|
&ValMaterializer);
|
|
|
|
// There is no need to map the arguments anymore.
|
|
for (Argument &Arg : Src.args())
|
|
ValueMap.erase(&Arg);
|
|
|
|
Src.dematerialize();
|
|
return false;
|
|
}
|
|
|
|
void ModuleLinker::linkAliasBody(GlobalAlias &Dst, GlobalAlias &Src) {
|
|
Constant *Aliasee = Src.getAliasee();
|
|
Constant *Val =
|
|
MapValue(Aliasee, ValueMap, RF_None, &TypeMap, &ValMaterializer);
|
|
Dst.setAliasee(Val);
|
|
}
|
|
|
|
bool ModuleLinker::linkGlobalValueBody(GlobalValue &Src) {
|
|
Value *Dst = ValueMap[&Src];
|
|
assert(Dst);
|
|
if (auto *F = dyn_cast<Function>(&Src))
|
|
return linkFunctionBody(cast<Function>(*Dst), *F);
|
|
if (auto *GVar = dyn_cast<GlobalVariable>(&Src)) {
|
|
linkGlobalInit(cast<GlobalVariable>(*Dst), *GVar);
|
|
return false;
|
|
}
|
|
linkAliasBody(cast<GlobalAlias>(*Dst), cast<GlobalAlias>(Src));
|
|
return false;
|
|
}
|
|
|
|
/// Insert all of the named MDNodes in Src into the Dest module.
|
|
void ModuleLinker::linkNamedMDNodes() {
|
|
const NamedMDNode *SrcModFlags = SrcM->getModuleFlagsMetadata();
|
|
for (const NamedMDNode &NMD : SrcM->named_metadata()) {
|
|
// Don't link module flags here. Do them separately.
|
|
if (&NMD == SrcModFlags)
|
|
continue;
|
|
NamedMDNode *DestNMD = DstM->getOrInsertNamedMetadata(NMD.getName());
|
|
// Add Src elements into Dest node.
|
|
for (const MDNode *op : NMD.operands())
|
|
DestNMD->addOperand(
|
|
MapMetadata(op, ValueMap, RF_None, &TypeMap, &ValMaterializer));
|
|
}
|
|
}
|
|
|
|
/// Drop DISubprograms that have been superseded.
|
|
///
|
|
/// FIXME: this creates an asymmetric result: we strip functions from losing
|
|
/// subprograms in DstM, but leave losing subprograms in SrcM.
|
|
/// TODO: Remove this logic once the backend can correctly determine canonical
|
|
/// subprograms.
|
|
void ModuleLinker::stripReplacedSubprograms() {
|
|
// Avoid quadratic runtime by returning early when there's nothing to do.
|
|
if (OverridingFunctions.empty())
|
|
return;
|
|
|
|
// Move the functions now, so the set gets cleared even on early returns.
|
|
auto Functions = std::move(OverridingFunctions);
|
|
OverridingFunctions.clear();
|
|
|
|
// Drop functions from subprograms if they've been overridden by the new
|
|
// compile unit.
|
|
NamedMDNode *CompileUnits = DstM->getNamedMetadata("llvm.dbg.cu");
|
|
if (!CompileUnits)
|
|
return;
|
|
for (unsigned I = 0, E = CompileUnits->getNumOperands(); I != E; ++I) {
|
|
auto *CU = cast<DICompileUnit>(CompileUnits->getOperand(I));
|
|
assert(CU && "Expected valid compile unit");
|
|
|
|
for (DISubprogram *SP : CU->getSubprograms()) {
|
|
if (!SP || !SP->getFunction() || !Functions.count(SP->getFunction()))
|
|
continue;
|
|
|
|
// Prevent DebugInfoFinder from tagging this as the canonical subprogram,
|
|
// since the canonical one is in the incoming module.
|
|
SP->replaceFunction(nullptr);
|
|
}
|
|
}
|
|
}
|
|
|
|
/// Merge the linker flags in Src into the Dest module.
|
|
bool ModuleLinker::linkModuleFlagsMetadata() {
|
|
// If the source module has no module flags, we are done.
|
|
const NamedMDNode *SrcModFlags = SrcM->getModuleFlagsMetadata();
|
|
if (!SrcModFlags) return false;
|
|
|
|
// If the destination module doesn't have module flags yet, then just copy
|
|
// over the source module's flags.
|
|
NamedMDNode *DstModFlags = DstM->getOrInsertModuleFlagsMetadata();
|
|
if (DstModFlags->getNumOperands() == 0) {
|
|
for (unsigned I = 0, E = SrcModFlags->getNumOperands(); I != E; ++I)
|
|
DstModFlags->addOperand(SrcModFlags->getOperand(I));
|
|
|
|
return false;
|
|
}
|
|
|
|
// First build a map of the existing module flags and requirements.
|
|
DenseMap<MDString *, std::pair<MDNode *, unsigned>> Flags;
|
|
SmallSetVector<MDNode*, 16> Requirements;
|
|
for (unsigned I = 0, E = DstModFlags->getNumOperands(); I != E; ++I) {
|
|
MDNode *Op = DstModFlags->getOperand(I);
|
|
ConstantInt *Behavior = mdconst::extract<ConstantInt>(Op->getOperand(0));
|
|
MDString *ID = cast<MDString>(Op->getOperand(1));
|
|
|
|
if (Behavior->getZExtValue() == Module::Require) {
|
|
Requirements.insert(cast<MDNode>(Op->getOperand(2)));
|
|
} else {
|
|
Flags[ID] = std::make_pair(Op, I);
|
|
}
|
|
}
|
|
|
|
// Merge in the flags from the source module, and also collect its set of
|
|
// requirements.
|
|
bool HasErr = false;
|
|
for (unsigned I = 0, E = SrcModFlags->getNumOperands(); I != E; ++I) {
|
|
MDNode *SrcOp = SrcModFlags->getOperand(I);
|
|
ConstantInt *SrcBehavior =
|
|
mdconst::extract<ConstantInt>(SrcOp->getOperand(0));
|
|
MDString *ID = cast<MDString>(SrcOp->getOperand(1));
|
|
MDNode *DstOp;
|
|
unsigned DstIndex;
|
|
std::tie(DstOp, DstIndex) = Flags.lookup(ID);
|
|
unsigned SrcBehaviorValue = SrcBehavior->getZExtValue();
|
|
|
|
// If this is a requirement, add it and continue.
|
|
if (SrcBehaviorValue == Module::Require) {
|
|
// If the destination module does not already have this requirement, add
|
|
// it.
|
|
if (Requirements.insert(cast<MDNode>(SrcOp->getOperand(2)))) {
|
|
DstModFlags->addOperand(SrcOp);
|
|
}
|
|
continue;
|
|
}
|
|
|
|
// If there is no existing flag with this ID, just add it.
|
|
if (!DstOp) {
|
|
Flags[ID] = std::make_pair(SrcOp, DstModFlags->getNumOperands());
|
|
DstModFlags->addOperand(SrcOp);
|
|
continue;
|
|
}
|
|
|
|
// Otherwise, perform a merge.
|
|
ConstantInt *DstBehavior =
|
|
mdconst::extract<ConstantInt>(DstOp->getOperand(0));
|
|
unsigned DstBehaviorValue = DstBehavior->getZExtValue();
|
|
|
|
// If either flag has override behavior, handle it first.
|
|
if (DstBehaviorValue == Module::Override) {
|
|
// Diagnose inconsistent flags which both have override behavior.
|
|
if (SrcBehaviorValue == Module::Override &&
|
|
SrcOp->getOperand(2) != DstOp->getOperand(2)) {
|
|
HasErr |= emitError("linking module flags '" + ID->getString() +
|
|
"': IDs have conflicting override values");
|
|
}
|
|
continue;
|
|
} else if (SrcBehaviorValue == Module::Override) {
|
|
// Update the destination flag to that of the source.
|
|
DstModFlags->setOperand(DstIndex, SrcOp);
|
|
Flags[ID].first = SrcOp;
|
|
continue;
|
|
}
|
|
|
|
// Diagnose inconsistent merge behavior types.
|
|
if (SrcBehaviorValue != DstBehaviorValue) {
|
|
HasErr |= emitError("linking module flags '" + ID->getString() +
|
|
"': IDs have conflicting behaviors");
|
|
continue;
|
|
}
|
|
|
|
auto replaceDstValue = [&](MDNode *New) {
|
|
Metadata *FlagOps[] = {DstOp->getOperand(0), ID, New};
|
|
MDNode *Flag = MDNode::get(DstM->getContext(), FlagOps);
|
|
DstModFlags->setOperand(DstIndex, Flag);
|
|
Flags[ID].first = Flag;
|
|
};
|
|
|
|
// Perform the merge for standard behavior types.
|
|
switch (SrcBehaviorValue) {
|
|
case Module::Require:
|
|
case Module::Override: llvm_unreachable("not possible");
|
|
case Module::Error: {
|
|
// Emit an error if the values differ.
|
|
if (SrcOp->getOperand(2) != DstOp->getOperand(2)) {
|
|
HasErr |= emitError("linking module flags '" + ID->getString() +
|
|
"': IDs have conflicting values");
|
|
}
|
|
continue;
|
|
}
|
|
case Module::Warning: {
|
|
// Emit a warning if the values differ.
|
|
if (SrcOp->getOperand(2) != DstOp->getOperand(2)) {
|
|
emitWarning("linking module flags '" + ID->getString() +
|
|
"': IDs have conflicting values");
|
|
}
|
|
continue;
|
|
}
|
|
case Module::Append: {
|
|
MDNode *DstValue = cast<MDNode>(DstOp->getOperand(2));
|
|
MDNode *SrcValue = cast<MDNode>(SrcOp->getOperand(2));
|
|
SmallVector<Metadata *, 8> MDs;
|
|
MDs.reserve(DstValue->getNumOperands() + SrcValue->getNumOperands());
|
|
MDs.append(DstValue->op_begin(), DstValue->op_end());
|
|
MDs.append(SrcValue->op_begin(), SrcValue->op_end());
|
|
|
|
replaceDstValue(MDNode::get(DstM->getContext(), MDs));
|
|
break;
|
|
}
|
|
case Module::AppendUnique: {
|
|
SmallSetVector<Metadata *, 16> Elts;
|
|
MDNode *DstValue = cast<MDNode>(DstOp->getOperand(2));
|
|
MDNode *SrcValue = cast<MDNode>(SrcOp->getOperand(2));
|
|
Elts.insert(DstValue->op_begin(), DstValue->op_end());
|
|
Elts.insert(SrcValue->op_begin(), SrcValue->op_end());
|
|
|
|
replaceDstValue(MDNode::get(DstM->getContext(),
|
|
makeArrayRef(Elts.begin(), Elts.end())));
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
// Check all of the requirements.
|
|
for (unsigned I = 0, E = Requirements.size(); I != E; ++I) {
|
|
MDNode *Requirement = Requirements[I];
|
|
MDString *Flag = cast<MDString>(Requirement->getOperand(0));
|
|
Metadata *ReqValue = Requirement->getOperand(1);
|
|
|
|
MDNode *Op = Flags[Flag].first;
|
|
if (!Op || Op->getOperand(2) != ReqValue) {
|
|
HasErr |= emitError("linking module flags '" + Flag->getString() +
|
|
"': does not have the required value");
|
|
continue;
|
|
}
|
|
}
|
|
|
|
return HasErr;
|
|
}
|
|
|
|
// This function returns true if the triples match.
|
|
static bool triplesMatch(const Triple &T0, const Triple &T1) {
|
|
// If vendor is apple, ignore the version number.
|
|
if (T0.getVendor() == Triple::Apple)
|
|
return T0.getArch() == T1.getArch() &&
|
|
T0.getSubArch() == T1.getSubArch() &&
|
|
T0.getVendor() == T1.getVendor() &&
|
|
T0.getOS() == T1.getOS();
|
|
|
|
return T0 == T1;
|
|
}
|
|
|
|
// This function returns the merged triple.
|
|
static std::string mergeTriples(const Triple &SrcTriple, const Triple &DstTriple) {
|
|
// If vendor is apple, pick the triple with the larger version number.
|
|
if (SrcTriple.getVendor() == Triple::Apple)
|
|
if (DstTriple.isOSVersionLT(SrcTriple))
|
|
return SrcTriple.str();
|
|
|
|
return DstTriple.str();
|
|
}
|
|
|
|
bool ModuleLinker::run() {
|
|
assert(DstM && "Null destination module");
|
|
assert(SrcM && "Null source module");
|
|
|
|
// Inherit the target data from the source module if the destination module
|
|
// doesn't have one already.
|
|
if (DstM->getDataLayout().isDefault())
|
|
DstM->setDataLayout(SrcM->getDataLayout());
|
|
|
|
if (SrcM->getDataLayout() != DstM->getDataLayout()) {
|
|
emitWarning("Linking two modules of different data layouts: '" +
|
|
SrcM->getModuleIdentifier() + "' is '" +
|
|
SrcM->getDataLayoutStr() + "' whereas '" +
|
|
DstM->getModuleIdentifier() + "' is '" +
|
|
DstM->getDataLayoutStr() + "'\n");
|
|
}
|
|
|
|
// Copy the target triple from the source to dest if the dest's is empty.
|
|
if (DstM->getTargetTriple().empty() && !SrcM->getTargetTriple().empty())
|
|
DstM->setTargetTriple(SrcM->getTargetTriple());
|
|
|
|
Triple SrcTriple(SrcM->getTargetTriple()), DstTriple(DstM->getTargetTriple());
|
|
|
|
if (!SrcM->getTargetTriple().empty() && !triplesMatch(SrcTriple, DstTriple))
|
|
emitWarning("Linking two modules of different target triples: " +
|
|
SrcM->getModuleIdentifier() + "' is '" +
|
|
SrcM->getTargetTriple() + "' whereas '" +
|
|
DstM->getModuleIdentifier() + "' is '" +
|
|
DstM->getTargetTriple() + "'\n");
|
|
|
|
DstM->setTargetTriple(mergeTriples(SrcTriple, DstTriple));
|
|
|
|
// Append the module inline asm string.
|
|
if (!SrcM->getModuleInlineAsm().empty()) {
|
|
if (DstM->getModuleInlineAsm().empty())
|
|
DstM->setModuleInlineAsm(SrcM->getModuleInlineAsm());
|
|
else
|
|
DstM->setModuleInlineAsm(DstM->getModuleInlineAsm()+"\n"+
|
|
SrcM->getModuleInlineAsm());
|
|
}
|
|
|
|
// Loop over all of the linked values to compute type mappings.
|
|
computeTypeMapping();
|
|
|
|
ComdatsChosen.clear();
|
|
for (const auto &SMEC : SrcM->getComdatSymbolTable()) {
|
|
const Comdat &C = SMEC.getValue();
|
|
if (ComdatsChosen.count(&C))
|
|
continue;
|
|
Comdat::SelectionKind SK;
|
|
bool LinkFromSrc;
|
|
if (getComdatResult(&C, SK, LinkFromSrc))
|
|
return true;
|
|
ComdatsChosen[&C] = std::make_pair(SK, LinkFromSrc);
|
|
}
|
|
|
|
// Upgrade mismatched global arrays.
|
|
upgradeMismatchedGlobals();
|
|
|
|
// Insert all of the globals in src into the DstM module... without linking
|
|
// initializers (which could refer to functions not yet mapped over).
|
|
for (GlobalVariable &GV : SrcM->globals())
|
|
if (linkGlobalValueProto(&GV))
|
|
return true;
|
|
|
|
// Link the functions together between the two modules, without doing function
|
|
// bodies... this just adds external function prototypes to the DstM
|
|
// function... We do this so that when we begin processing function bodies,
|
|
// all of the global values that may be referenced are available in our
|
|
// ValueMap.
|
|
for (Function &F :*SrcM)
|
|
if (linkGlobalValueProto(&F))
|
|
return true;
|
|
|
|
// If there were any aliases, link them now.
|
|
for (GlobalAlias &GA : SrcM->aliases())
|
|
if (linkGlobalValueProto(&GA))
|
|
return true;
|
|
|
|
for (const AppendingVarInfo &AppendingVar : AppendingVars)
|
|
linkAppendingVarInit(AppendingVar);
|
|
|
|
for (const auto &Entry : DstM->getComdatSymbolTable()) {
|
|
const Comdat &C = Entry.getValue();
|
|
if (C.getSelectionKind() == Comdat::Any)
|
|
continue;
|
|
const GlobalValue *GV = SrcM->getNamedValue(C.getName());
|
|
if (GV)
|
|
MapValue(GV, ValueMap, RF_None, &TypeMap, &ValMaterializer);
|
|
}
|
|
|
|
// Strip replaced subprograms before mapping any metadata -- so that we're
|
|
// not changing metadata from the source module (note that
|
|
// linkGlobalValueBody() eventually calls RemapInstruction() and therefore
|
|
// MapMetadata()) -- but after linking global value protocols -- so that
|
|
// OverridingFunctions has been built.
|
|
stripReplacedSubprograms();
|
|
|
|
// Link in the function bodies that are defined in the source module into
|
|
// DstM.
|
|
for (Function &SF : *SrcM) {
|
|
// Skip if no body (function is external).
|
|
if (SF.isDeclaration())
|
|
continue;
|
|
|
|
// Skip if not linking from source.
|
|
if (DoNotLinkFromSource.count(&SF))
|
|
continue;
|
|
|
|
if (linkGlobalValueBody(SF))
|
|
return true;
|
|
}
|
|
|
|
// Resolve all uses of aliases with aliasees.
|
|
for (GlobalAlias &Src : SrcM->aliases()) {
|
|
if (DoNotLinkFromSource.count(&Src))
|
|
continue;
|
|
linkGlobalValueBody(Src);
|
|
}
|
|
|
|
// Remap all of the named MDNodes in Src into the DstM module. We do this
|
|
// after linking GlobalValues so that MDNodes that reference GlobalValues
|
|
// are properly remapped.
|
|
linkNamedMDNodes();
|
|
|
|
// Merge the module flags into the DstM module.
|
|
if (linkModuleFlagsMetadata())
|
|
return true;
|
|
|
|
// Update the initializers in the DstM module now that all globals that may
|
|
// be referenced are in DstM.
|
|
for (GlobalVariable &Src : SrcM->globals()) {
|
|
// Only process initialized GV's or ones not already in dest.
|
|
if (!Src.hasInitializer() || DoNotLinkFromSource.count(&Src))
|
|
continue;
|
|
linkGlobalValueBody(Src);
|
|
}
|
|
|
|
// Process vector of lazily linked in functions.
|
|
while (!LazilyLinkGlobalValues.empty()) {
|
|
GlobalValue *SGV = LazilyLinkGlobalValues.back();
|
|
LazilyLinkGlobalValues.pop_back();
|
|
|
|
assert(!SGV->isDeclaration() && "users should not pass down decls");
|
|
if (linkGlobalValueBody(*SGV))
|
|
return true;
|
|
}
|
|
|
|
return false;
|
|
}
|
|
|
|
Linker::StructTypeKeyInfo::KeyTy::KeyTy(ArrayRef<Type *> E, bool P)
|
|
: ETypes(E), IsPacked(P) {}
|
|
|
|
Linker::StructTypeKeyInfo::KeyTy::KeyTy(const StructType *ST)
|
|
: ETypes(ST->elements()), IsPacked(ST->isPacked()) {}
|
|
|
|
bool Linker::StructTypeKeyInfo::KeyTy::operator==(const KeyTy &That) const {
|
|
if (IsPacked != That.IsPacked)
|
|
return false;
|
|
if (ETypes != That.ETypes)
|
|
return false;
|
|
return true;
|
|
}
|
|
|
|
bool Linker::StructTypeKeyInfo::KeyTy::operator!=(const KeyTy &That) const {
|
|
return !this->operator==(That);
|
|
}
|
|
|
|
StructType *Linker::StructTypeKeyInfo::getEmptyKey() {
|
|
return DenseMapInfo<StructType *>::getEmptyKey();
|
|
}
|
|
|
|
StructType *Linker::StructTypeKeyInfo::getTombstoneKey() {
|
|
return DenseMapInfo<StructType *>::getTombstoneKey();
|
|
}
|
|
|
|
unsigned Linker::StructTypeKeyInfo::getHashValue(const KeyTy &Key) {
|
|
return hash_combine(hash_combine_range(Key.ETypes.begin(), Key.ETypes.end()),
|
|
Key.IsPacked);
|
|
}
|
|
|
|
unsigned Linker::StructTypeKeyInfo::getHashValue(const StructType *ST) {
|
|
return getHashValue(KeyTy(ST));
|
|
}
|
|
|
|
bool Linker::StructTypeKeyInfo::isEqual(const KeyTy &LHS,
|
|
const StructType *RHS) {
|
|
if (RHS == getEmptyKey() || RHS == getTombstoneKey())
|
|
return false;
|
|
return LHS == KeyTy(RHS);
|
|
}
|
|
|
|
bool Linker::StructTypeKeyInfo::isEqual(const StructType *LHS,
|
|
const StructType *RHS) {
|
|
if (RHS == getEmptyKey())
|
|
return LHS == getEmptyKey();
|
|
|
|
if (RHS == getTombstoneKey())
|
|
return LHS == getTombstoneKey();
|
|
|
|
return KeyTy(LHS) == KeyTy(RHS);
|
|
}
|
|
|
|
void Linker::IdentifiedStructTypeSet::addNonOpaque(StructType *Ty) {
|
|
assert(!Ty->isOpaque());
|
|
NonOpaqueStructTypes.insert(Ty);
|
|
}
|
|
|
|
void Linker::IdentifiedStructTypeSet::switchToNonOpaque(StructType *Ty) {
|
|
assert(!Ty->isOpaque());
|
|
NonOpaqueStructTypes.insert(Ty);
|
|
bool Removed = OpaqueStructTypes.erase(Ty);
|
|
(void)Removed;
|
|
assert(Removed);
|
|
}
|
|
|
|
void Linker::IdentifiedStructTypeSet::addOpaque(StructType *Ty) {
|
|
assert(Ty->isOpaque());
|
|
OpaqueStructTypes.insert(Ty);
|
|
}
|
|
|
|
StructType *
|
|
Linker::IdentifiedStructTypeSet::findNonOpaque(ArrayRef<Type *> ETypes,
|
|
bool IsPacked) {
|
|
Linker::StructTypeKeyInfo::KeyTy Key(ETypes, IsPacked);
|
|
auto I = NonOpaqueStructTypes.find_as(Key);
|
|
if (I == NonOpaqueStructTypes.end())
|
|
return nullptr;
|
|
return *I;
|
|
}
|
|
|
|
bool Linker::IdentifiedStructTypeSet::hasType(StructType *Ty) {
|
|
if (Ty->isOpaque())
|
|
return OpaqueStructTypes.count(Ty);
|
|
auto I = NonOpaqueStructTypes.find(Ty);
|
|
if (I == NonOpaqueStructTypes.end())
|
|
return false;
|
|
return *I == Ty;
|
|
}
|
|
|
|
void Linker::init(Module *M, DiagnosticHandlerFunction DiagnosticHandler) {
|
|
this->Composite = M;
|
|
this->DiagnosticHandler = DiagnosticHandler;
|
|
|
|
TypeFinder StructTypes;
|
|
StructTypes.run(*M, true);
|
|
for (StructType *Ty : StructTypes) {
|
|
if (Ty->isOpaque())
|
|
IdentifiedStructTypes.addOpaque(Ty);
|
|
else
|
|
IdentifiedStructTypes.addNonOpaque(Ty);
|
|
}
|
|
}
|
|
|
|
Linker::Linker(Module *M, DiagnosticHandlerFunction DiagnosticHandler) {
|
|
init(M, DiagnosticHandler);
|
|
}
|
|
|
|
Linker::Linker(Module *M) {
|
|
init(M, [this](const DiagnosticInfo &DI) {
|
|
Composite->getContext().diagnose(DI);
|
|
});
|
|
}
|
|
|
|
Linker::~Linker() {
|
|
}
|
|
|
|
void Linker::deleteModule() {
|
|
delete Composite;
|
|
Composite = nullptr;
|
|
}
|
|
|
|
bool Linker::linkInModule(Module *Src, bool OverrideSymbols) {
|
|
ModuleLinker TheLinker(Composite, IdentifiedStructTypes, Src,
|
|
DiagnosticHandler, OverrideSymbols);
|
|
bool RetCode = TheLinker.run();
|
|
Composite->dropTriviallyDeadConstantArrays();
|
|
return RetCode;
|
|
}
|
|
|
|
void Linker::setModule(Module *Dst) {
|
|
init(Dst, DiagnosticHandler);
|
|
}
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
// LinkModules entrypoint.
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
/// This function links two modules together, with the resulting Dest module
|
|
/// modified to be the composite of the two input modules. If an error occurs,
|
|
/// true is returned and ErrorMsg (if not null) is set to indicate the problem.
|
|
/// Upon failure, the Dest module could be in a modified state, and shouldn't be
|
|
/// relied on to be consistent.
|
|
bool Linker::LinkModules(Module *Dest, Module *Src,
|
|
DiagnosticHandlerFunction DiagnosticHandler) {
|
|
Linker L(Dest, DiagnosticHandler);
|
|
return L.linkInModule(Src);
|
|
}
|
|
|
|
bool Linker::LinkModules(Module *Dest, Module *Src) {
|
|
Linker L(Dest);
|
|
return L.linkInModule(Src);
|
|
}
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
// C API.
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
LLVMBool LLVMLinkModules(LLVMModuleRef Dest, LLVMModuleRef Src,
|
|
LLVMLinkerMode Unused, char **OutMessages) {
|
|
Module *D = unwrap(Dest);
|
|
std::string Message;
|
|
raw_string_ostream Stream(Message);
|
|
DiagnosticPrinterRawOStream DP(Stream);
|
|
|
|
LLVMBool Result = Linker::LinkModules(
|
|
D, unwrap(Src), [&](const DiagnosticInfo &DI) { DI.print(DP); });
|
|
|
|
if (OutMessages && Result) {
|
|
Stream.flush();
|
|
*OutMessages = strdup(Message.c_str());
|
|
}
|
|
return Result;
|
|
}
|