Add support for parsing the DW_AT_ranges attributes

This enables the DWARF reader to properly parse DW_AT_ranges attributes
in compilation units and functions. Code covered by a function is now
represented by a vector of ranges instead of a single contiguous range
and DW_AT_ranges entries are used to populate it. All the code and tests
that assumed functions to be contiguous entities has been updated to
reflect the change. DW_AT_ranges attributes found in compilation units
are parsed but no data is generated for them as it is not currently needed.

BUG=754

Change-Id: I310391b525aaba0dd329f1e3187486f2e0c6d442
Reviewed-on: https://chromium-review.googlesource.com/1124721
Reviewed-by: Ted Mielczarek <ted.mielczarek@gmail.com>

1 files changed, 79 insertions, 0 deletions

diff --git a/src/common/dwarf_range_list_handler.h b/src/common/dwarf_range_list_handler.h
new file mode 100644
index 00000000..bd099686
--- /dev/null
+++ b/src/common/dwarf_range_list_handler.h
@@ -0,0 +1,79 @@
+// -*- mode: c++ -*-
+
+// Copyright (c) 2018 Google Inc.
+// All rights reserved.
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+// Original author: Gabriele Svelto <gsvelto@mozilla.com>
+//                                  <gabriele.svelto@gmail.com>
+
+// The DwarfRangeListHandler class accepts rangelist data from a DWARF parser
+// and adds it to a google_breakpad::Function or other objects supporting
+// ranges.
+
+#ifndef COMMON_LINUX_DWARF_RANGE_LIST_HANDLER_H
+#define COMMON_LINUX_DWARF_RANGE_LIST_HANDLER_H
+
+#include <vector>
+
+#include "common/module.h"
+#include "common/dwarf/dwarf2reader.h"
+
+namespace google_breakpad {
+
+// A class for producing a vector of google_breakpad::Module::Range
+// instances from a parsed DWARF range list.
+
+class DwarfRangeListHandler: public dwarf2reader::RangeListHandler {
+ public:
+  DwarfRangeListHandler(uint64 base_address, vector<Module::Range> *ranges)
+      : base_address_(base_address), ranges_(ranges) { }
+
+  ~DwarfRangeListHandler() { }
+
+  // Add a range to the list
+  void AddRange(uint64 begin, uint64 end);
+
+  // Record the new base address and use it for the following entries
+  void SetBaseAddress(uint64 base_address);
+
+  // Sort the ranges so that they are in ascending order of starting address
+  void Finish();
+
+ private:
+  // The current PC to add to every entry, this can be overridden by a special
+  // list entry
+  uint64 base_address_;
+
+  // The list of ranges to be populated
+  vector<Module::Range> *ranges_;
+};
+
+} // namespace google_breakpad
+
+#endif // COMMON_LINUX_DWARF_RANGE_LIST_HANDLER_H