[PATCH] Initial DWARF64 support for .debug_line

[Eric Christopher]

  The patch itself is ok, though it needs a few things:

  a) comments on what is and is not handled for dwarf64. The compile unit header is probably the best place to document that there's at least some partial support for reading line tables.

  b) testcase. I'm ok with adding the testcase and a comment on it that dwarf64 parsing isn't very good at this point and that the only thing that's expected to work are the line tables. You can, for now, just dump the line table in the testcase.

http://llvm-reviews.chandlerc.com/D1988