Rui Ueyama 3f851704c1 Move new lld's code to Common subdirectory.
New lld's files are spread under lib subdirectory, and it isn't easy
to find which files are actually maintained. This patch moves maintained
files to Common subdirectory.

Differential Revision: https://reviews.llvm.org/D37645

llvm-svn: 314719
2017-10-02 21:00:41 +00:00

133 lines
3.5 KiB
C++

//===- lib/ReaderWriter/MachO/ObjCPass.cpp -------------------------------===//
//
// The LLVM Linker
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
//===----------------------------------------------------------------------===//
#include "ArchHandler.h"
#include "File.h"
#include "MachONormalizedFileBinaryUtils.h"
#include "MachOPasses.h"
#include "lld/Common/LLVM.h"
#include "lld/Core/DefinedAtom.h"
#include "lld/Core/File.h"
#include "lld/Core/Reference.h"
#include "lld/Core/Simple.h"
#include "lld/ReaderWriter/MachOLinkingContext.h"
#include "llvm/ADT/DenseMap.h"
#include "llvm/ADT/STLExtras.h"
namespace lld {
namespace mach_o {
///
/// ObjC Image Info Atom created by the ObjC pass.
///
class ObjCImageInfoAtom : public SimpleDefinedAtom {
public:
ObjCImageInfoAtom(const File &file, bool isBig,
MachOLinkingContext::ObjCConstraint objCConstraint,
uint32_t swiftVersion)
: SimpleDefinedAtom(file) {
Data.info.version = 0;
switch (objCConstraint) {
case MachOLinkingContext::objc_unknown:
llvm_unreachable("Shouldn't run the objc pass without a constraint");
case MachOLinkingContext::objc_supports_gc:
case MachOLinkingContext::objc_gc_only:
llvm_unreachable("GC is not supported");
case MachOLinkingContext::objc_retainReleaseForSimulator:
// The retain/release for simulator flag is already the correct
// encoded value for the data so just set it here.
Data.info.flags = (uint32_t)objCConstraint;
break;
case MachOLinkingContext::objc_retainRelease:
// We don't need to encode this flag, so just leave the flags as 0.
Data.info.flags = 0;
break;
}
Data.info.flags |= (swiftVersion << 8);
normalized::write32(Data.bytes + 4, Data.info.flags, isBig);
}
~ObjCImageInfoAtom() override = default;
ContentType contentType() const override {
return DefinedAtom::typeObjCImageInfo;
}
Alignment alignment() const override {
return 4;
}
uint64_t size() const override {
return 8;
}
ContentPermissions permissions() const override {
return DefinedAtom::permR__;
}
ArrayRef<uint8_t> rawContent() const override {
return llvm::makeArrayRef(Data.bytes, size());
}
private:
struct objc_image_info {
uint32_t version;
uint32_t flags;
};
union {
objc_image_info info;
uint8_t bytes[8];
} Data;
};
class ObjCPass : public Pass {
public:
ObjCPass(const MachOLinkingContext &context)
: _ctx(context),
_file(*_ctx.make_file<MachOFile>("<mach-o objc pass>")) {
_file.setOrdinal(_ctx.getNextOrdinalAndIncrement());
}
llvm::Error perform(SimpleFile &mergedFile) override {
// Add the image info.
mergedFile.addAtom(*getImageInfo());
return llvm::Error::success();
}
private:
const DefinedAtom* getImageInfo() {
bool IsBig = MachOLinkingContext::isBigEndian(_ctx.arch());
return new (_file.allocator()) ObjCImageInfoAtom(_file, IsBig,
_ctx.objcConstraint(),
_ctx.swiftVersion());
}
const MachOLinkingContext &_ctx;
MachOFile &_file;
};
void addObjCPass(PassManager &pm, const MachOLinkingContext &ctx) {
pm.add(llvm::make_unique<ObjCPass>(ctx));
}
} // end namespace mach_o
} // end namespace lld