[Bug tree-optimization/48648] internal compiler error: in translate_clast, at graphite-clast-to-gimple.c:1123

[spop at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=48648

--- Comment #11 from Sebastian Pop <spop at gcc dot gnu.org> 2011-07-28 
21:57:15 UTC ---
Author: spop
Date: Thu Jul 28 21:57:10 2011
New Revision: 176901

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=176901
Log:
Fix PR48648: Handle CLAST assignments.

The CLAST produced by CLooG-ISL contains an assignment and GCC chokes
on it.  The exact CLAST contains an assignment followed by an if:

scat_1 = max(0,ceild(T_4-7,8));
if (scat_1 <= min(1,floord(T_4-1,8))) {
  S7(scat_1);
}

This is equivalent to a loop that iterates only once, and so CLooG
generates an assignment followed by an if instead of a loop.  This is
an important optimization that was improved in ISL, that allows
if-conversion: imagine GCC having to figure out that a loop like the
following actually iterates only once, and can be converted to an if:

for (scat_1 = max(0,ceild(T_4-7,8)); scat_1 <= min(1,floord(T_4-1,8));
scat_1++)
  S7(scat_1);

This patch implements the translation of CLAST assignments.
Bootstrapped and tested on amd64-linux.

2011-07-28  Sebastian Pop  <sebastian....@amd.com>

    PR middle-end/48648
    * graphite-clast-to-gimple.c (clast_get_body_of_loop): Handle
    CLAST assignments.
    (translate_clast): Same.
    (translate_clast_assignment): New.

    * gcc.dg/graphite/id-pr48648.c: New.

Added:
    trunk/gcc/testsuite/gcc.dg/graphite/id-pr48648.c
Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/graphite-clast-to-gimple.c
    trunk/gcc/testsuite/ChangeLog