[Bug debug/59992] [4.9 Regression] Compilation of insn-recog.c too slow due to var-tracking

[aoliva at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=59992

--- Comment #10 from Alexandre Oliva <aoliva at gcc dot gnu.org> ---
Created attachment 32214
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=32214&action=edit
preserve permanent values in a separate table

vt_initialize still took way too long in the insn-recog testcase, going over
the entire table so as to preserve constants and equivalences over and over and
over.  That's silly.  Moving to a separate table everything that is permanent
avoids this complexity without significant drawbacks.  With this patch,
vt_initialize time goes down from the improved 500 seconds to 5 seconds. 
Wheee!