The following function should just "return 1":
int f(int i)
{
int i1 = i -2;
if (i1 > i)
return 0;
return 1;
}
We miss this on the tree level, I found this while look into the following
fortran code:
SUBROUTINE d ( a, b,n)
IMPLICIT NONE
INTEGER :: n
REAL,DIMENSION(n) :: a
REAL,DIMENSION(n) :: b
b(n-2:n) = sqrt(a(n-2:n))
END SUBROUTINE d
In final_cleanup, we have:
D.679 = *n;
S.2 = D.679 - 2;
if (D.679 < S.2) goto L.1; else goto <L7>;
--
Summary: missed always false conditional
Product: gcc
Version: 4.1.0
Status: UNCONFIRMED
Keywords: missed-optimization, TREE
Severity: enhancement
Priority: P2
Component: tree-optimization
AssignedTo: unassigned at gcc dot gnu dot org
ReportedBy: pinskia at gcc dot gnu dot org
CC: gcc-bugs at gcc dot gnu dot org
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=20922
