[Bug tree-optimization/15558] New: [tree-ssa] A missed forward propagation opportunity involving floats

["kazu at cs dot umass dot edu" <gcc-bugzilla at gcc dot gnu dot org>]

Consider:

void bar (void);

void
foo (float a, float b)
{
  if (!(a < b))
    bar ();
}

I get:

foo (a, b)
{
  _Bool T.1;
  _Bool T.0;

<bb 0>:
  T.0_3 = a_1 < b_2;
  if (T.0_3 == 0) goto <L0>; else goto <L1>;

<L0>:;
  bar () [tail call];

<L1>:;
  return;

}

We could simply say

  if (a_1 < b_3) goto <L1>; else goto <L0>;

Note that I've flipped the two labels.

-- 
           Summary: [tree-ssa] A missed forward propagation opportunity
                    involving floats
           Product: gcc
           Version: 3.5.0
            Status: UNCONFIRMED
          Severity: enhancement
          Priority: P2
         Component: tree-optimization
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: kazu at cs dot umass dot edu
                CC: gcc-bugs at gcc dot gnu dot org


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=15558