DWARF: Port support for parsing .debug_aranges section from LLDB and wire it up to llvm-dwarfdump.

This is only one half of it, the part that caches address ranges from the DIEs when .debug_aranges is
not available will be ported soon.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@139680 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 75 insertions, 0 deletions

diff --git a/lib/DebugInfo/DWARFDebugArangeSet.h b/lib/DebugInfo/DWARFDebugArangeSet.h
new file mode 100644
index 0000000000..56bebc5379
--- /dev/null
+++ b/lib/DebugInfo/DWARFDebugArangeSet.h
@@ -0,0 +1,75 @@
+//===-- DWARFDebugArangeSet.h -----------------------------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_DEBUGINFO_DWARFDEBUGARANGESET_H
+#define LLVM_DEBUGINFO_DWARFDEBUGARANGESET_H
+
+#include "llvm/Support/DataExtractor.h"
+#include <vector>
+
+namespace llvm {
+
+class raw_ostream;
+
+class DWARFDebugArangeSet {
+public:
+  struct Header {
+    // The total length of the entries for that set, not including the length
+    // field itself.
+    uint32_t Length;
+    // The DWARF version number.
+    uint16_t Version;
+    // The offset from the beginning of the .debug_info section of the
+    // compilation unit entry referenced by the table.
+    uint32_t CuOffset;
+    // The size in bytes of an address on the target architecture. For segmented
+    // addressing, this is the size of the offset portion of the address.
+    uint8_t AddrSize;
+    // The size in bytes of a segment descriptor on the target architecture.
+    // If the target system uses a flat address space, this value is 0.
+    uint8_t SegSize;
+  };
+
+  struct Descriptor {
+    uint64_t Address;
+    uint64_t Length;
+    uint64_t getEndAddress() const { return Address + Length; }
+  };
+
+private:
+  typedef std::vector<Descriptor> DescriptorColl;
+  typedef DescriptorColl::iterator DescriptorIter;
+  typedef DescriptorColl::const_iterator DescriptorConstIter;
+
+  uint32_t Offset;
+  Header Header;
+  DescriptorColl ArangeDescriptors;
+
+public:
+  DWARFDebugArangeSet() { clear(); }
+  void clear();
+  void compact();
+  bool extract(DataExtractor data, uint32_t *offset_ptr);
+  void dump(raw_ostream &OS) const;
+
+  uint32_t getCompileUnitDIEOffset() const { return Header.CuOffset; }
+  uint32_t getOffsetOfNextEntry() const { return Offset + Header.Length + 4; }
+  uint32_t findAddress(uint64_t address) const;
+  uint32_t getNumDescriptors() const { return ArangeDescriptors.size(); }
+  const struct Header &getHeader() const { return Header; }
+  const Descriptor *getDescriptor(uint32_t i) const {
+    if (i < ArangeDescriptors.size())
+      return &ArangeDescriptors[i];
+    return NULL;
+  }
+};
+
+}
+
+#endif