This is the mail archive of the gcc-bugs@gcc.gnu.org mailing list for the GCC project.


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]
Other format: [Raw text]

[Bug rtl-optimization/55611] Operand swapping for commutative operators


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55611

--- Comment #1 from Marc Glisse <glisse at gcc dot gnu.org> 2012-12-11 22:12:01 UTC ---
Created attachment 28931
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=28931
Use tree code to determine the canonical order

In this patch, I remove the external calls to commutative_operand_precedence,
and I compare GET_CODEs when the current function would say the arguments are
equivalent. This passes bootstrap+testsuite except for one test:
gfortran.dg/pr43229.f90  -O  (internal compiler error)
that I killed when it was 12GB.

I also tried the reverse order (just swap x and y in the GET_CODE comparison).
It got a crazy process during stage3 compiling tree-ssa-address.c (I killed it
at 40GB). Before that, I had tried parts of the testsuite with a
non-bootstrapped compiler, and it seemed to pass just fine.


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]