[PATCH] D18477: Drop debug info for DISubprograms that are not referenced by anything

[Adrian Prantl via llvm-commits]

aprantl added a comment.

Here's some data:

Baseline (compiling llc RelWithDebugAsserts)

  find lib-OLD -name '*.o' | xargs dwarfdump --file-stats
  
    File       symtab            strtab            code data         DWARF debug       STABS debug       other             file
   =========  ================= ================= ================= ================= ================= ================= =======================================
  1449525800    1417344   0.10%   5616761   0.39%  26037272   1.80%1349841343  93.12%         0   0.00%  66613080   4.60%
  Average sizes:
     1884949       1843   0.10%      7303   0.39%     33858   1.80%   1755320  93.12%         0   0.00%     86622   4.60%

with this patch:

  find lib -name '*.o' | xargs dwarfdump --file-stats
  
   File       symtab            strtab            code data         DWARF debug       STABS debug       other             file
   =========  ================= ================= ================= ================= ================= ================= =======================================
  1449515428    1417280   0.10%   5616555   0.39%  26036518   1.80%1349833958  93.12%         0   0.00%  66611117   4.60%
  Average sizes:
     1884935       1843   0.10%      7303   0.39%     33857   1.80%   1755310  93.12%         0   0.00%     86620   4.60%

We're saving a hot 7kb of DWARF on llc.


http://reviews.llvm.org/D18477