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[Bug debug/49676] inefficiency: DW_AT_GNU_call_site_value calculates everything << 32


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=49676

--- Comment #5 from Jakub Jelinek <jakub at gcc dot gnu.org> 2011-07-11 13:00:57 UTC ---
Created attachment 24739
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=24739
gcc47-pr49676-const.patch

I've noticed that int_loc_descriptor sometimes emits too large ops to build
large constants, many constants can be actually emitted using shorter sequences
of more, but smaller, ops, e.g. DW_OP_lit31 DW_OP_lit31 DW_OP_shl
is just 3 bytes, while DW_OP_constu 0xf80000000 is 7 bytes long.
Similarly, DW_OP_plus_uconst isn't always a win.


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