This patch implements reading the directory information for source
files in the dwarf3 reader.
Basically, the change consists in replacing in the DiInlLoc struct
      const HChar* filename;     /* caller source filename */
      UInt   fndn_ix;            /* index in di->fndnpool of caller source
                                    dirname/filename */

A similar change is done in  DiVariable struct, as the
read_filename_Table code is shared between the inline info reader
and the varinfo reader.
Note however that outputting dirname in variable description
is not done. Unclear if that is desired or not.
It should be trivially doable however.
Replacing filename by fndn_ix implies a bunch of semi-mechanical

The code to read the directory names is in the new function
XArray* read_dirname_xa (struct _DebugInfo* di, const HChar *compdir,
                         Cursor *c,
                         Bool td3 )

Note that readdwarf.c and readdwarf3.c have significant duplicated
logic. Would be nice to integrate these 2 dwarf readers in one
single reader. This function is directly inspired from
an equivalent piece of code in readdwarf.c.

Modified memcheck/tests/varinfo5.vgtest to test the dirname appears
in the inlined functions.

Impact on memory is neglectable (a few Kb on a big executable).

git-svn-id: svn:// a5019735-40e9-0310-863c-91ae7b9d1cf9
8 files changed