[PATCH] D32228: [DWARF] - Take relocations in account when exctracting ranges from .debug_ranges

[George Rimar via Phabricator via llvm-commits]

grimar created this revision.
Herald added a subscriber: aprantl.

I found this when investigated "Bug 32319 - .gdb_index is broken/incomplete" for LLD.

When we have object file with .debug_ranges section it may be filled with zeroes.
Relocations are exist in file to relocate this zeroes into real values later, but until that
a pair of zeroes is treated as terminator. And DWARF parser thinks there is no ranges at all
when I am trying to collect address ranges for building .gdb_index.

Solution implemented in this patch is to take relocations in account when parsing ranges.
FWIW DWARFFormValue::extractValue() already do that for calculating DW_AT_low_pc/DW_AT_high_pc,
when ranges are not involved. So solution seems to be consistent with existent code.


https://reviews.llvm.org/D32228

Files:
  include/llvm/DebugInfo/DWARF/DWARFCompileUnit.h
  include/llvm/DebugInfo/DWARF/DWARFContext.h
  include/llvm/DebugInfo/DWARF/DWARFDebugRangeList.h
  include/llvm/DebugInfo/DWARF/DWARFTypeUnit.h
  include/llvm/DebugInfo/DWARF/DWARFUnit.h
  lib/DebugInfo/DWARF/DWARFContext.cpp
  lib/DebugInfo/DWARF/DWARFDebugRangeList.cpp
  lib/DebugInfo/DWARF/DWARFUnit.cpp
  test/DebugInfo/dwarfdump-ranges-unrelocated.s
  tools/dsymutil/DwarfLinker.cpp

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