1 files changed, 79 insertions, 0 deletions
diff --git a/contrib/llvm-project/lld/MachO/UnwindInfoSection.h b/contrib/llvm-project/lld/MachO/UnwindInfoSection.h
new file mode 100644
index 000000000000..2285cf930d83
--- /dev/null
+++ b/contrib/llvm-project/lld/MachO/UnwindInfoSection.h
@@ -0,0 +1,79 @@
+//===- 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;
+  }
+
+  using EncodingMap = llvm::DenseMap<compact_unwind_encoding_t, size_t>;
+
+  struct SecondLevelPage {
+    uint32_t kind;
+    size_t entryIndex;
+    size_t entryCount;
+    size_t byteCount;
+    std::vector<compact_unwind_encoding_t> localEncodings;
+    EncodingMap localEncodingIndexes;
+  };
+
+private:
+  std::vector<std::pair<compact_unwind_encoding_t, size_t>> commonEncodings;
+  EncodingMap commonEncodingIndexes;
+  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<SecondLevelPage> secondLevelPages;
+  MergedOutputSection *compactUnwindSection = nullptr;
+  uint64_t level2PagesOffset = 0;
+  uint64_t unwindInfoSize = 0;
+};
+
+} // namespace macho
+} // namespace lld
+
+#endif