isl_aff_nonneg_basic_set and isl_aff_zero_basic_set: simplify result

The constructed constraint may be a tautology in which case it needs
to be simplified away, especially if it is an equality.

We probably want to perform this simplification in
isl_basic_set_from_constraint instead, but CLooG currently depends
on the resulting basic set not being simplified.
We would have to fix CLooG first before we can change this behavior.

Signed-off-by: Sven Verdoolaege <skimo@kotnet.org>

diff --git a/isl_aff.c b/isl_aff.c
index d0e1010..42000ce 100644 (file)
--- a/isl_aff.c
+++ b/isl_aff.c
@@ -1011,10 +1011,13 @@ __isl_give isl_aff *isl_aff_gist_params(__isl_take isl_aff *aff,
 __isl_give isl_basic_set *isl_aff_nonneg_basic_set(__isl_take isl_aff *aff)
 {
        isl_constraint *ineq;
+       isl_basic_set *bset;
 
        ineq = isl_inequality_from_aff(aff);
 
-       return isl_basic_set_from_constraint(ineq);
+       bset = isl_basic_set_from_constraint(ineq);
+       bset = isl_basic_set_simplify(bset);
+       return bset;
 }
 
 /* Return a basic set containing those elements in the space
@@ -1023,10 +1026,13 @@ __isl_give isl_basic_set *isl_aff_nonneg_basic_set(__isl_take isl_aff *aff)
 __isl_give isl_basic_set *isl_aff_zero_basic_set(__isl_take isl_aff *aff)
 {
        isl_constraint *ineq;
+       isl_basic_set *bset;
 
        ineq = isl_equality_from_aff(aff);
 
-       return isl_basic_set_from_constraint(ineq);
+       bset = isl_basic_set_from_constraint(ineq);
+       bset = isl_basic_set_simplify(bset);
+       return bset;
 }
 
 /* Return a basic set containing those elements in the shared space