llvm-project/lld/MachO/UnwindInfoSection.h

85 lines
2.8 KiB
C++

//===- UnwindInfoSection.h ------------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
#ifndef LLD_MACHO_UNWIND_INFO_H
#define LLD_MACHO_UNWIND_INFO_H
#include "MergedOutputSection.h"
#include "SyntheticSections.h"
#include "mach-o/compact_unwind_encoding.h"
#include "llvm/ADT/DenseMap.h"
#include <vector>
// In 2020, we mostly care about 64-bit targets: x86_64 and arm64
struct CompactUnwindEntry64 {
uint64_t functionAddress;
uint32_t functionLength;
compact_unwind_encoding_t encoding;
uint64_t personality;
uint64_t lsda;
};
// FIXME(gkm): someday we might care about 32-bit targets: x86 & arm
struct CompactUnwindEntry32 {
uint32_t functionAddress;
uint32_t functionLength;
compact_unwind_encoding_t encoding;
uint32_t personality;
uint32_t lsda;
};
namespace lld {
namespace macho {
class UnwindInfoSection : public SyntheticSection {
public:
UnwindInfoSection();
uint64_t getSize() const override { return unwindInfoSize; }
bool isNeeded() const override;
void finalize() override;
void writeTo(uint8_t *buf) const override;
void setCompactUnwindSection(MergedOutputSection *cuSection) {
compactUnwindSection = cuSection;
}
private:
std::vector<std::pair<compact_unwind_encoding_t, size_t>> commonEncodings;
std::vector<uint32_t> personalities;
std::vector<unwind_info_section_header_lsda_index_entry> lsdaEntries;
std::vector<CompactUnwindEntry64> cuVector;
std::vector<const CompactUnwindEntry64 *> cuPtrVector;
std::vector<std::vector<const CompactUnwindEntry64 *>::const_iterator>
pageBounds;
MergedOutputSection *compactUnwindSection = nullptr;
uint64_t level2PagesOffset = 0;
uint64_t unwindInfoSize = 0;
};
#define UNWIND_INFO_COMMON_ENCODINGS_MAX 127
#define UNWIND_INFO_SECOND_LEVEL_PAGE_SIZE 4096
#define UNWIND_INFO_REGULAR_SECOND_LEVEL_ENTRIES_MAX \
((UNWIND_INFO_SECOND_LEVEL_PAGE_SIZE - \
sizeof(unwind_info_regular_second_level_page_header)) / \
sizeof(unwind_info_regular_second_level_entry))
#define UNWIND_INFO_COMPRESSED_SECOND_LEVEL_ENTRIES_MAX \
((UNWIND_INFO_SECOND_LEVEL_PAGE_SIZE - \
sizeof(unwind_info_compressed_second_level_page_header)) / \
sizeof(uint32_t))
#define UNWIND_INFO_COMPRESSED_ENTRY_FUNC_OFFSET_BITS 24
#define UNWIND_INFO_COMPRESSED_ENTRY_FUNC_OFFSET_MASK \
UNWIND_INFO_COMPRESSED_ENTRY_FUNC_OFFSET(~0)
} // namespace macho
} // namespace lld
#endif