rename isl_pw_aff_add to isl_pw_aff_union_add
[platform/upstream/isl.git] / isl_pw_templ.c
index aa5fda4..ddabbc5 100644 (file)
@@ -99,9 +99,9 @@ __isl_give PW *FN(PW,alloc)(__isl_take isl_set *set, __isl_take EL *el)
                goto error;
 
 #ifdef HAS_TYPE
-       pw = FN(PW,alloc_size)(isl_set_get_space(set), type, 1);
+       pw = FN(PW,alloc_size)(FN(EL,get_space)(el), type, 1);
 #else
-       pw = FN(PW,alloc_size)(isl_set_get_space(set), 1);
+       pw = FN(PW,alloc_size)(FN(EL,get_space)(el), 1);
 #endif
 
        return FN(PW,add_piece)(pw, set, el);
@@ -173,6 +173,33 @@ void *FN(PW,free)(__isl_take PW *pw)
        return NULL;
 }
 
+const char *FN(PW,get_dim_name)(__isl_keep PW *pw, enum isl_dim_type type,
+       unsigned pos)
+{
+       return pw ? isl_space_get_dim_name(pw->dim, type, pos) : NULL;
+}
+
+__isl_give isl_id *FN(PW,get_dim_id)(__isl_keep PW *pw, enum isl_dim_type type,
+       unsigned pos)
+{
+       return pw ? isl_space_get_dim_id(pw->dim, type, pos) : NULL;
+}
+
+const char *FN(PW,get_tuple_name)(__isl_keep PW *pw, enum isl_dim_type type)
+{
+       return pw ? isl_space_get_tuple_name(pw->dim, type) : NULL;
+}
+
+int FN(PW,has_tuple_id)(__isl_keep PW *pw, enum isl_dim_type type)
+{
+       return pw ? isl_space_has_tuple_id(pw->dim, type) : -1;
+}
+
+__isl_give isl_id *FN(PW,get_tuple_id)(__isl_keep PW *pw, enum isl_dim_type type)
+{
+       return pw ? isl_space_get_tuple_id(pw->dim, type) : NULL;
+}
+
 int FN(PW,IS_ZERO)(__isl_keep PW *pw)
 {
        if (!pw)
@@ -182,7 +209,8 @@ int FN(PW,IS_ZERO)(__isl_keep PW *pw)
 }
 
 #ifndef NO_REALIGN
-__isl_give PW *FN(PW,realign)(__isl_take PW *pw, __isl_take isl_reordering *exp)
+__isl_give PW *FN(PW,realign_domain)(__isl_take PW *pw,
+       __isl_take isl_reordering *exp)
 {
        int i;
 
@@ -195,13 +223,13 @@ __isl_give PW *FN(PW,realign)(__isl_take PW *pw, __isl_take isl_reordering *exp)
                                                    isl_reordering_copy(exp));
                if (!pw->p[i].set)
                        goto error;
-               pw->p[i].FIELD = FN(EL,realign)(pw->p[i].FIELD,
+               pw->p[i].FIELD = FN(EL,realign_domain)(pw->p[i].FIELD,
                                                    isl_reordering_copy(exp));
                if (!pw->p[i].FIELD)
                        goto error;
        }
 
-       pw = FN(PW,reset_space)(pw, isl_space_copy(exp->dim));
+       pw = FN(PW,reset_domain_space)(pw, isl_space_copy(exp->dim));
 
        isl_reordering_free(exp);
        return pw;
@@ -235,8 +263,9 @@ __isl_give PW *FN(PW,align_params)(__isl_take PW *pw, __isl_take isl_space *mode
                model = isl_space_drop_dims(model, isl_dim_out,
                                        0, isl_space_dim(model, isl_dim_out));
                exp = isl_parameter_alignment_reordering(pw->dim, model);
-               exp = isl_reordering_extend_space(exp, FN(PW,get_space)(pw));
-               pw = FN(PW,realign)(pw, exp);
+               exp = isl_reordering_extend_space(exp,
+                                       FN(PW,get_domain_space)(pw));
+               pw = FN(PW,realign_domain)(pw, exp);
        }
 
        isl_space_free(model);
@@ -247,7 +276,7 @@ error:
        return NULL;
 }
 
-static __isl_give PW *align_params_pw_pw_and(__isl_take PW *pw1,
+static __isl_give PW *FN(PW,align_params_pw_pw_and)(__isl_take PW *pw1,
        __isl_take PW *pw2,
        __isl_give PW *(*fn)(__isl_take PW *pw1, __isl_take PW *pw2))
 {
@@ -271,7 +300,7 @@ error:
        return NULL;
 }
 
-static __isl_give PW *align_params_pw_set_and(__isl_take PW *pw,
+static __isl_give PW *FN(PW,align_params_pw_set_and)(__isl_take PW *pw,
        __isl_take isl_set *set,
        __isl_give PW *(*fn)(__isl_take PW *pw, __isl_take isl_set *set))
 {
@@ -296,7 +325,8 @@ error:
 }
 #endif
 
-static __isl_give PW *FN(PW,add_aligned)(__isl_take PW *pw1, __isl_take PW *pw2)
+static __isl_give PW *FN(PW,union_add_aligned)(__isl_take PW *pw1,
+       __isl_take PW *pw2)
 {
        int i, j, n;
        struct PW *res;
@@ -372,9 +402,13 @@ error:
        return NULL;
 }
 
-__isl_give PW *FN(PW,add)(__isl_take PW *pw1, __isl_take PW *pw2)
+/* Private version of "union_add".  For isl_pw_qpolynomial and
+ * isl_pw_qpolynomial_fold, we prefer to simply call it "add".
+ */
+static __isl_give PW *FN(PW,union_add_)(__isl_take PW *pw1, __isl_take PW *pw2)
 {
-       return align_params_pw_pw_and(pw1, pw2, &FN(PW,add_aligned));
+       return FN(PW,align_params_pw_pw_and)(pw1, pw2,
+                                               &FN(PW,union_add_aligned));
 }
 
 /* Make sure "pw" has room for at least "n" more pieces.
@@ -466,7 +500,62 @@ error:
 
 __isl_give PW *FN(PW,add_disjoint)(__isl_take PW *pw1, __isl_take PW *pw2)
 {
-       return align_params_pw_pw_and(pw1, pw2, &FN(PW,add_disjoint_aligned));
+       return FN(PW,align_params_pw_pw_and)(pw1, pw2,
+                                               &FN(PW,add_disjoint_aligned));
+}
+
+/* This function is currently only used from isl_aff.c
+ */
+static __isl_give PW *FN(PW,on_shared_domain)(__isl_take PW *pw1,
+       __isl_take PW *pw2,
+       __isl_give EL *(*fn)(__isl_take EL *el1, __isl_take EL *el2))
+       __attribute__ ((unused));
+
+/* Apply "fn" to pairs of elements from pw1 and pw2 on shared domains.
+ */
+static __isl_give PW *FN(PW,on_shared_domain)(__isl_take PW *pw1,
+       __isl_take PW *pw2,
+       __isl_give EL *(*fn)(__isl_take EL *el1, __isl_take EL *el2))
+{
+       int i, j, n;
+       PW *res;
+
+       if (!pw1 || !pw2)
+               goto error;
+
+       n = pw1->n * pw2->n;
+#ifdef HAS_TYPE
+       res = FN(PW,alloc_size)(isl_space_copy(pw1->dim), pw1->type, n);
+#else
+       res = FN(PW,alloc_size)(isl_space_copy(pw1->dim), n);
+#endif
+
+       for (i = 0; i < pw1->n; ++i) {
+               for (j = 0; j < pw2->n; ++j) {
+                       isl_set *common;
+                       EL *res_ij;
+                       common = isl_set_intersect(
+                                       isl_set_copy(pw1->p[i].set),
+                                       isl_set_copy(pw2->p[j].set));
+                       if (isl_set_plain_is_empty(common)) {
+                               isl_set_free(common);
+                               continue;
+                       }
+
+                       res_ij = fn(FN(EL,copy)(pw1->p[i].FIELD),
+                                   FN(EL,copy)(pw2->p[j].FIELD));
+
+                       res = FN(PW,add_piece)(res, common, res_ij);
+               }
+       }
+
+       FN(PW,free)(pw1);
+       FN(PW,free)(pw2);
+       return res;
+error:
+       FN(PW,free)(pw1);
+       FN(PW,free)(pw2);
+       return NULL;
 }
 
 #ifndef NO_NEG
@@ -513,7 +602,7 @@ __isl_give isl_qpolynomial *FN(PW,eval)(__isl_take PW *pw,
                goto error;
        ctx = isl_point_get_ctx(pnt);
        pnt_dim = isl_point_get_space(pnt);
-       isl_assert(ctx, isl_space_is_equal(pnt_dim, pw->dim), goto error);
+       isl_assert(ctx, isl_space_is_domain(pnt_dim, pw->dim), goto error);
 
        for (i = 0; i < pw->n; ++i) {
                found = isl_set_contains_point(pw->p[i].set, pnt);
@@ -526,7 +615,7 @@ __isl_give isl_qpolynomial *FN(PW,eval)(__isl_take PW *pw,
                qp = FN(EL,eval)(FN(EL,copy)(pw->p[i].FIELD),
                                            isl_point_copy(pnt));
        else
-               qp = isl_qpolynomial_zero(isl_space_copy(pw->dim));
+               qp = isl_qpolynomial_zero_on_domain(FN(PW,get_domain_space)(pw));
        FN(PW,free)(pw);
        isl_space_free(pnt_dim);
        isl_point_free(pnt);
@@ -547,7 +636,7 @@ __isl_give isl_set *FN(PW,domain)(__isl_take PW *pw)
        if (!pw)
                return NULL;
 
-       dom = isl_set_empty(isl_space_copy(pw->dim));
+       dom = isl_set_empty(FN(PW,get_domain_space)(pw));
        for (i = 0; i < pw->n; ++i)
                dom = isl_set_union_disjoint(dom, isl_set_copy(pw->p[i].set));
 
@@ -581,6 +670,8 @@ static __isl_give PW *FN(PW,intersect_domain_aligned)(__isl_take PW *pw,
                aff = isl_set_affine_hull(isl_set_copy(pw->p[i].set));
                pw->p[i].FIELD = FN(EL,substitute_equalities)(pw->p[i].FIELD,
                                                                aff);
+               if (!pw->p[i].FIELD)
+                       goto error;
                if (isl_set_plain_is_empty(pw->p[i].set)) {
                        isl_set_free(pw->p[i].set);
                        FN(EL,free)(pw->p[i].FIELD);
@@ -601,7 +692,7 @@ error:
 __isl_give PW *FN(PW,intersect_domain)(__isl_take PW *pw,
        __isl_take isl_set *context)
 {
-       return align_params_pw_set_and(pw, context,
+       return FN(PW,align_params_pw_set_and)(pw, context,
                                        &FN(PW,intersect_domain_aligned));
 }
 
@@ -665,7 +756,7 @@ error:
 
 __isl_give PW *FN(PW,gist)(__isl_take PW *pw, __isl_take isl_set *context)
 {
-       return align_params_pw_set_and(pw, context, &FN(PW,gist_aligned));
+       return FN(PW,align_params_pw_set_and)(pw, context, &FN(PW,gist_aligned));
 }
 
 __isl_give PW *FN(PW,coalesce)(__isl_take PW *pw)
@@ -713,17 +804,22 @@ int FN(PW,involves_dims)(__isl_keep PW *pw, enum isl_dim_type type,
        unsigned first, unsigned n)
 {
        int i;
+       enum isl_dim_type set_type;
 
        if (!pw)
                return -1;
        if (pw->n == 0 || n == 0)
                return 0;
+
+       set_type = type == isl_dim_in ? isl_dim_set : type;
+
        for (i = 0; i < pw->n; ++i) {
                int involves = FN(EL,involves_dims)(pw->p[i].FIELD,
                                                        type, first, n);
                if (involves < 0 || involves)
                        return involves;
-               involves = isl_set_involves_dims(pw->p[i].set, type, first, n);
+               involves = isl_set_involves_dims(pw->p[i].set,
+                                                       set_type, first, n);
                if (involves < 0 || involves)
                        return involves;
        }
@@ -735,17 +831,21 @@ __isl_give PW *FN(PW,set_dim_name)(__isl_take PW *pw,
        enum isl_dim_type type, unsigned pos, const char *s)
 {
        int i;
+       enum isl_dim_type set_type;
 
        pw = FN(PW,cow)(pw);
        if (!pw)
                return NULL;
 
+       set_type = type == isl_dim_in ? isl_dim_set : type;
+
        pw->dim = isl_space_set_dim_name(pw->dim, type, pos, s);
        if (!pw->dim)
                goto error;
 
        for (i = 0; i < pw->n; ++i) {
-               pw->p[i].set = isl_set_set_dim_name(pw->p[i].set, type, pos, s);
+               pw->p[i].set = isl_set_set_dim_name(pw->p[i].set,
+                                                       set_type, pos, s);
                if (!pw->p[i].set)
                        goto error;
                pw->p[i].FIELD = FN(EL,set_dim_name)(pw->p[i].FIELD, type, pos, s);
@@ -764,12 +864,15 @@ __isl_give PW *FN(PW,drop_dims)(__isl_take PW *pw,
        enum isl_dim_type type, unsigned first, unsigned n)
 {
        int i;
+       enum isl_dim_type set_type;
 
        if (!pw)
                return NULL;
        if (n == 0 && !isl_space_get_tuple_name(pw->dim, type))
                return pw;
 
+       set_type = type == isl_dim_in ? isl_dim_set : type;
+
        pw = FN(PW,cow)(pw);
        if (!pw)
                return NULL;
@@ -777,7 +880,7 @@ __isl_give PW *FN(PW,drop_dims)(__isl_take PW *pw,
        if (!pw->dim)
                goto error;
        for (i = 0; i < pw->n; ++i) {
-               pw->p[i].set = isl_set_drop(pw->p[i].set, type, first, n);
+               pw->p[i].set = isl_set_drop(pw->p[i].set, set_type, first, n);
                if (!pw->p[i].set)
                        goto error;
                pw->p[i].FIELD = FN(EL,drop_dims)(pw->p[i].FIELD, type, first, n);
@@ -800,12 +903,15 @@ __isl_give PW *FN(PW,project_out)(__isl_take PW *pw,
        enum isl_dim_type type, unsigned first, unsigned n)
 {
        int i;
+       enum isl_dim_type set_type;
 
        if (!pw)
                return NULL;
        if (n == 0 && !isl_space_get_tuple_name(pw->dim, type))
                return pw;
 
+       set_type = type == isl_dim_in ? isl_dim_set : type;
+
        pw = FN(PW,cow)(pw);
        if (!pw)
                return NULL;
@@ -813,7 +919,8 @@ __isl_give PW *FN(PW,project_out)(__isl_take PW *pw,
        if (!pw->dim)
                goto error;
        for (i = 0; i < pw->n; ++i) {
-               pw->p[i].set = isl_set_project_out(pw->p[i].set, type, first, n);
+               pw->p[i].set = isl_set_project_out(pw->p[i].set,
+                                                       set_type, first, n);
                if (!pw->p[i].set)
                        goto error;
                pw->p[i].FIELD = FN(EL,drop_dims)(pw->p[i].FIELD, type, first, n);
@@ -826,6 +933,21 @@ error:
        FN(PW,free)(pw);
        return NULL;
 }
+
+/* Project the domain of pw onto its parameter space.
+ */
+__isl_give PW *FN(PW,project_domain_on_params)(__isl_take PW *pw)
+{
+       isl_space *space;
+       unsigned n;
+
+       n = FN(PW,dim)(pw, isl_dim_in);
+       pw = FN(PW,project_out)(pw, isl_dim_in, 0, n);
+       space = FN(PW,get_domain_space)(pw);
+       space = isl_space_params(space);
+       pw = FN(PW,reset_domain_space)(pw, space);
+       return pw;
+}
 #endif
 
 #ifndef NO_INSERT_DIMS
@@ -833,12 +955,15 @@ __isl_give PW *FN(PW,insert_dims)(__isl_take PW *pw, enum isl_dim_type type,
        unsigned first, unsigned n)
 {
        int i;
+       enum isl_dim_type set_type;
 
        if (!pw)
                return NULL;
        if (n == 0 && !isl_space_is_named_or_nested(pw->dim, type))
                return pw;
 
+       set_type = type == isl_dim_in ? isl_dim_set : type;
+
        pw = FN(PW,cow)(pw);
        if (!pw)
                return NULL;
@@ -849,7 +974,7 @@ __isl_give PW *FN(PW,insert_dims)(__isl_take PW *pw, enum isl_dim_type type,
 
        for (i = 0; i < pw->n; ++i) {
                pw->p[i].set = isl_set_insert_dims(pw->p[i].set,
-                                                               type, first, n);
+                                                           set_type, first, n);
                if (!pw->p[i].set)
                        goto error;
                pw->p[i].FIELD = FN(EL,insert_dims)(pw->p[i].FIELD,
@@ -873,6 +998,9 @@ __isl_give PW *FN(PW,fix_dim)(__isl_take PW *pw,
        if (!pw)
                return NULL;
 
+       if (type == isl_dim_in)
+               type = isl_dim_set;
+
        pw = FN(PW,cow)(pw);
        if (!pw)
                return NULL;
@@ -903,6 +1031,9 @@ __isl_give PW *FN(PW,split_dims)(__isl_take PW *pw,
        if (n == 0)
                return pw;
 
+       if (type == isl_dim_in)
+               type = isl_dim_set;
+
        pw = FN(PW,cow)(pw);
        if (!pw)
                return NULL;
@@ -937,7 +1068,7 @@ __isl_give isl_qpolynomial *FN(PW,opt)(__isl_take PW *pw, int max)
        if (pw->n == 0) {
                isl_space *dim = isl_space_copy(pw->dim);
                FN(PW,free)(pw);
-               return isl_qpolynomial_zero(dim);
+               return isl_qpolynomial_zero_on_domain(dim);
        }
 
        opt = FN(EL,opt_on_domain)(FN(EL,copy)(pw->p[0].FIELD),
@@ -972,34 +1103,91 @@ __isl_give isl_space *FN(PW,get_space)(__isl_keep PW *pw)
        return pw ? isl_space_copy(pw->dim) : NULL;
 }
 
+__isl_give isl_space *FN(PW,get_domain_space)(__isl_keep PW *pw)
+{
+       return pw ? isl_space_domain(isl_space_copy(pw->dim)) : NULL;
+}
+
 #ifndef NO_RESET_DIM
-__isl_give PW *FN(PW,reset_space)(__isl_take PW *pw, __isl_take isl_space *dim)
+/* Reset the space of "pw".  Since we don't know if the elements
+ * represent the spaces themselves or their domains, we pass along
+ * both when we call their reset_space_and_domain.
+ */
+static __isl_give PW *FN(PW,reset_space_and_domain)(__isl_take PW *pw,
+       __isl_take isl_space *space, __isl_take isl_space *domain)
 {
        int i;
 
        pw = FN(PW,cow)(pw);
-       if (!pw || !dim)
+       if (!pw || !space || !domain)
                goto error;
 
        for (i = 0; i < pw->n; ++i) {
                pw->p[i].set = isl_set_reset_space(pw->p[i].set,
-                                                isl_space_copy(dim));
+                                                isl_space_copy(domain));
                if (!pw->p[i].set)
                        goto error;
-               pw->p[i].FIELD = FN(EL,reset_space)(pw->p[i].FIELD,
-                                                 isl_space_copy(dim));
+               pw->p[i].FIELD = FN(EL,reset_space_and_domain)(pw->p[i].FIELD,
+                             isl_space_copy(space), isl_space_copy(domain));
                if (!pw->p[i].FIELD)
                        goto error;
        }
+
+       isl_space_free(domain);
+
        isl_space_free(pw->dim);
-       pw->dim = dim;
+       pw->dim = space;
 
        return pw;
 error:
-       isl_space_free(dim);
+       isl_space_free(domain);
+       isl_space_free(space);
        FN(PW,free)(pw);
        return NULL;
 }
+
+__isl_give PW *FN(PW,reset_domain_space)(__isl_take PW *pw,
+       __isl_take isl_space *domain)
+{
+       isl_space *space;
+
+       space = isl_space_extend_domain_with_range(isl_space_copy(domain),
+                                                  FN(PW,get_space)(pw));
+       return FN(PW,reset_space_and_domain)(pw, space, domain);
+}
+
+__isl_give PW *FN(PW,reset_space)(__isl_take PW *pw, __isl_take isl_space *dim)
+{
+       isl_space *domain;
+
+       domain = isl_space_domain(isl_space_copy(dim));
+       return FN(PW,reset_space_and_domain)(pw, dim, domain);
+}
+
+__isl_give PW *FN(PW,set_tuple_id)(__isl_keep PW *pw, enum isl_dim_type type,
+       __isl_take isl_id *id)
+{
+       isl_space *space;
+
+       pw = FN(PW,cow)(pw);
+       if (!pw)
+               return isl_id_free(id);
+
+       space = FN(PW,get_space)(pw);
+       space = isl_space_set_tuple_id(space, type, id);
+
+       return FN(PW,reset_space)(pw, space);
+}
+
+__isl_give PW *FN(PW,set_dim_id)(__isl_take PW *pw,
+       enum isl_dim_type type, unsigned pos, __isl_take isl_id *id)
+{
+       pw = FN(PW,cow)(pw);
+       if (!pw)
+               return isl_id_free(id);
+       pw->dim = isl_space_set_dim_id(pw->dim, type, pos, id);
+       return FN(PW,reset_space)(pw, isl_space_copy(pw->dim));
+}
 #endif
 
 int FN(PW,has_equal_space)(__isl_keep PW *pw1, __isl_keep PW *pw2)
@@ -1011,7 +1199,8 @@ int FN(PW,has_equal_space)(__isl_keep PW *pw1, __isl_keep PW *pw2)
 }
 
 #ifndef NO_MORPH
-__isl_give PW *FN(PW,morph)(__isl_take PW *pw, __isl_take isl_morph *morph)
+__isl_give PW *FN(PW,morph_domain)(__isl_take PW *pw,
+       __isl_take isl_morph *morph)
 {
        int i;
        isl_ctx *ctx;
@@ -1020,14 +1209,14 @@ __isl_give PW *FN(PW,morph)(__isl_take PW *pw, __isl_take isl_morph *morph)
                goto error;
 
        ctx = isl_space_get_ctx(pw->dim);
-       isl_assert(ctx, isl_space_is_equal(pw->dim, morph->dom->dim),
+       isl_assert(ctx, isl_space_is_domain(morph->dom->dim, pw->dim),
                goto error);
 
        pw = FN(PW,cow)(pw);
        if (!pw)
                goto error;
-       isl_space_free(pw->dim);
-       pw->dim = isl_space_copy(morph->ran->dim);
+       pw->dim = isl_space_extend_domain_with_range(
+                       isl_space_copy(morph->ran->dim), pw->dim);
        if (!pw->dim)
                goto error;
 
@@ -1035,7 +1224,7 @@ __isl_give PW *FN(PW,morph)(__isl_take PW *pw, __isl_take isl_morph *morph)
                pw->p[i].set = isl_morph_set(isl_morph_copy(morph), pw->p[i].set);
                if (!pw->p[i].set)
                        goto error;
-               pw->p[i].FIELD = FN(EL,morph)(pw->p[i].FIELD,
+               pw->p[i].FIELD = FN(EL,morph_domain)(pw->p[i].FIELD,
                                                isl_morph_copy(morph));
                if (!pw->p[i].FIELD)
                        goto error;
@@ -1160,15 +1349,23 @@ __isl_give PW *FN(PW,move_dims)(__isl_take PW *pw,
                goto error;
 
        for (i = 0; i < pw->n; ++i) {
+               pw->p[i].FIELD = FN(EL,move_dims)(pw->p[i].FIELD,
+                                       dst_type, dst_pos, src_type, src_pos, n);
+               if (!pw->p[i].FIELD)
+                       goto error;
+       }
+
+       if (dst_type == isl_dim_in)
+               dst_type = isl_dim_set;
+       if (src_type == isl_dim_in)
+               src_type = isl_dim_set;
+
+       for (i = 0; i < pw->n; ++i) {
                pw->p[i].set = isl_set_move_dims(pw->p[i].set,
                                                dst_type, dst_pos,
                                                src_type, src_pos, n);
                if (!pw->p[i].set)
                        goto error;
-               pw->p[i].FIELD = FN(EL,move_dims)(pw->p[i].FIELD,
-                                       dst_type, dst_pos, src_type, src_pos, n);
-               if (!pw->p[i].FIELD)
-                       goto error;
        }
 
        return pw;
@@ -1221,3 +1418,96 @@ __isl_give PW *FN(PW,scale)(__isl_take PW *pw, isl_int v)
 {
        return FN(PW,mul_isl_int)(pw, v);
 }
+
+static int FN(PW,qsort_set_cmp)(const void *p1, const void *p2)
+{
+       const isl_set *set1 = *(const isl_set **)p1;
+       const isl_set *set2 = *(const isl_set **)p2;
+
+       return isl_set_plain_cmp(set1, set2);
+}
+
+/* We normalize in place, but if anything goes wrong we need
+ * to return NULL, so we need to make sure we don't change the
+ * meaning of any possible other copies of map.
+ */
+__isl_give PW *FN(PW,normalize)(__isl_take PW *pw)
+{
+       int i, j;
+       isl_set *set;
+
+       if (!pw)
+               return NULL;
+       for (i = 0; i < pw->n; ++i) {
+               set = isl_set_normalize(isl_set_copy(pw->p[i].set));
+               if (!set)
+                       return FN(PW,free)(pw);
+               isl_set_free(pw->p[i].set);
+               pw->p[i].set = set;
+       }
+       qsort(pw->p, pw->n, sizeof(pw->p[0]), &FN(PW,qsort_set_cmp));
+       for (i = pw->n - 1; i >= 1; --i) {
+               if (!isl_set_plain_is_equal(pw->p[i - 1].set, pw->p[i].set))
+                       continue;
+               if (!FN(EL,plain_is_equal)(pw->p[i - 1].FIELD, pw->p[i].FIELD))
+                       continue;
+               set = isl_set_union(isl_set_copy(pw->p[i - 1].set),
+                                   isl_set_copy(pw->p[i].set));
+               if (!set)
+                       return FN(PW,free)(pw);
+               isl_set_free(pw->p[i].set);
+               FN(EL,free)(pw->p[i].FIELD);
+               isl_set_free(pw->p[i - 1].set);
+               pw->p[i - 1].set = set;
+               for (j = i + 1; j < pw->n; ++j)
+                       pw->p[j - 1] = pw->p[j];
+               pw->n--;
+       }
+
+       return pw;
+}
+
+/* Is pw1 obviously equal to pw2?
+ * That is, do they have obviously identical cells and obviously identical
+ * elements on each cell?
+ */
+int FN(PW,plain_is_equal)(__isl_keep PW *pw1, __isl_keep PW *pw2)
+{
+       int i;
+       int equal;
+
+       if (!pw1 || !pw2)
+               return -1;
+
+       if (pw1 == pw2)
+               return 1;
+       if (!isl_space_is_equal(pw1->dim, pw2->dim))
+               return 0;
+
+       pw1 = FN(PW,copy)(pw1);
+       pw2 = FN(PW,copy)(pw2);
+       pw1 = FN(PW,normalize)(pw1);
+       pw2 = FN(PW,normalize)(pw2);
+       if (!pw1 || !pw2)
+               goto error;
+
+       equal = pw1->n == pw2->n;
+       for (i = 0; equal && i < pw1->n; ++i) {
+               equal = isl_set_plain_is_equal(pw1->p[i].set, pw2->p[i].set);
+               if (equal < 0)
+                       goto error;
+               if (!equal)
+                       break;
+               equal = FN(EL,plain_is_equal)(pw1->p[i].FIELD, pw2->p[i].FIELD);
+               if (equal < 0)
+                       goto error;
+       }
+
+       FN(PW,free)(pw1);
+       FN(PW,free)(pw2);
+       return equal;
+error:
+       FN(PW,free)(pw1);
+       FN(PW,free)(pw2);
+       return -1;
+}