align parameters of arguments to binary isl_map and isl_pw_aff functions
[platform/upstream/isl.git] / isl_dim.c
index 13a68b8..6afd2cb 100644 (file)
--- a/isl_dim.c
+++ b/isl_dim.c
@@ -1,14 +1,24 @@
 /*
  * Copyright 2008-2009 Katholieke Universiteit Leuven
+ * Copyright 2010      INRIA Saclay
  *
  * Use of this software is governed by the GNU LGPLv2.1 license
  *
  * Written by Sven Verdoolaege, K.U.Leuven, Departement
  * Computerwetenschappen, Celestijnenlaan 200A, B-3001 Leuven, Belgium
+ * and INRIA Saclay - Ile-de-France, Parc Club Orsay Universite,
+ * ZAC des vignes, 4 rue Jacques Monod, 91893 Orsay, France 
  */
 
+#include <stdlib.h>
 #include <isl_dim_private.h>
-#include "isl_name.h"
+#include <isl_id_private.h>
+#include <isl_reordering.h>
+
+isl_ctx *isl_dim_get_ctx(__isl_keep isl_dim *dim)
+{
+       return dim ? dim->ctx : NULL;
+}
 
 struct isl_dim *isl_dim_alloc(struct isl_ctx *ctx,
                        unsigned nparam, unsigned n_in, unsigned n_out)
@@ -26,8 +36,14 @@ struct isl_dim *isl_dim_alloc(struct isl_ctx *ctx,
        dim->n_in = n_in;
        dim->n_out = n_out;
 
-       dim->n_name = 0;
-       dim->names = NULL;
+       dim->tuple_id[0] = NULL;
+       dim->tuple_id[1] = NULL;
+
+       dim->nested[0] = NULL;
+       dim->nested[1] = NULL;
+
+       dim->n_id = 0;
+       dim->ids = NULL;
 
        return dim;
 }
@@ -59,32 +75,32 @@ static unsigned global_pos(struct isl_dim *dim,
        return isl_dim_total(dim);
 }
 
-/* Extend length of names array to the total number of dimensions.
+/* Extend length of ids array to the total number of dimensions.
  */
-static __isl_give isl_dim *extend_names(__isl_take isl_dim *dim)
+static __isl_give isl_dim *extend_ids(__isl_take isl_dim *dim)
 {
-       struct isl_name **names;
+       isl_id **ids;
        int i;
 
-       if (isl_dim_total(dim) <= dim->n_name)
+       if (isl_dim_total(dim) <= dim->n_id)
                return dim;
 
-       if (!dim->names) {
-               dim->names = isl_calloc_array(dim->ctx,
-                               struct isl_name *, isl_dim_total(dim));
-               if (!dim->names)
+       if (!dim->ids) {
+               dim->ids = isl_calloc_array(dim->ctx,
+                               isl_id *, isl_dim_total(dim));
+               if (!dim->ids)
                        goto error;
        } else {
-               names = isl_realloc_array(dim->ctx, dim->names,
-                               struct isl_name *, isl_dim_total(dim));
-               if (!names)
+               ids = isl_realloc_array(dim->ctx, dim->ids,
+                               isl_id *, isl_dim_total(dim));
+               if (!ids)
                        goto error;
-               dim->names = names;
-               for (i = dim->n_name; i < isl_dim_total(dim); ++i)
-                       dim->names[i] = NULL;
+               dim->ids = ids;
+               for (i = dim->n_id; i < isl_dim_total(dim); ++i)
+                       dim->ids[i] = NULL;
        }
 
-       dim->n_name = isl_dim_total(dim);
+       dim->n_id = isl_dim_total(dim);
 
        return dim;
 error:
@@ -92,37 +108,36 @@ error:
        return NULL;
 }
 
-static struct isl_dim *set_name(struct isl_dim *dim,
-                                enum isl_dim_type type, unsigned pos,
-                                struct isl_name *name)
+static __isl_give isl_dim *set_id(__isl_take isl_dim *dim,
+       enum isl_dim_type type, unsigned pos, __isl_take isl_id *id)
 {
-       struct isl_ctx *ctx = dim->ctx;
        dim = isl_dim_cow(dim);
 
        if (!dim)
                goto error;
 
        pos = global_pos(dim, type, pos);
-       isl_assert(ctx, pos != isl_dim_total(dim), goto error);
+       if (pos == isl_dim_total(dim))
+               goto error;
 
-       if (pos >= dim->n_name) {
-               if (!name)
+       if (pos >= dim->n_id) {
+               if (!id)
                        return dim;
-               dim = extend_names(dim);
+               dim = extend_ids(dim);
                if (!dim)
                        goto error;
        }
 
-       dim->names[pos] = name;
+       dim->ids[pos] = id;
 
        return dim;
 error:
-       isl_name_free(ctx, name);
+       isl_id_free(id);
        isl_dim_free(dim);
        return NULL;
 }
 
-static struct isl_name *get_name(struct isl_dim *dim,
+static __isl_keep isl_id *get_id(__isl_keep isl_dim *dim,
                                 enum isl_dim_type type, unsigned pos)
 {
        if (!dim)
@@ -131,9 +146,9 @@ static struct isl_name *get_name(struct isl_dim *dim,
        pos = global_pos(dim, type, pos);
        if (pos == isl_dim_total(dim))
                return NULL;
-       if (pos >= dim->n_name)
+       if (pos >= dim->n_id)
                return NULL;
-       return dim->names[pos];
+       return dim->ids[pos];
 }
 
 static unsigned offset(struct isl_dim *dim, enum isl_dim_type type)
@@ -142,6 +157,7 @@ static unsigned offset(struct isl_dim *dim, enum isl_dim_type type)
        case isl_dim_param:     return 0;
        case isl_dim_in:        return dim->nparam;
        case isl_dim_out:       return dim->nparam + dim->n_in;
+       default:                return 0;
        }
 }
 
@@ -151,6 +167,8 @@ static unsigned n(struct isl_dim *dim, enum isl_dim_type type)
        case isl_dim_param:     return dim->nparam;
        case isl_dim_in:        return dim->n_in;
        case isl_dim_out:       return dim->n_out;
+       case isl_dim_all:       return dim->nparam + dim->n_in + dim->n_out;
+       default:                return 0;
        }
 }
 
@@ -161,19 +179,28 @@ unsigned isl_dim_size(struct isl_dim *dim, enum isl_dim_type type)
        return n(dim, type);
 }
 
-static struct isl_dim *copy_names(struct isl_dim *dst,
-       enum isl_dim_type dst_type, unsigned offset, struct isl_dim *src,
+unsigned isl_dim_offset(__isl_keep isl_dim *dim, enum isl_dim_type type)
+{
+       if (!dim)
+               return 0;
+       return offset(dim, type);
+}
+
+static __isl_give isl_dim *copy_ids(__isl_take isl_dim *dst,
+       enum isl_dim_type dst_type, unsigned offset, __isl_keep isl_dim *src,
        enum isl_dim_type src_type)
 {
        int i;
-       struct isl_name *name;
+       isl_id *id;
+
+       if (!dst)
+               return NULL;
 
        for (i = 0; i < n(src, src_type); ++i) {
-               name = get_name(src, src_type, i);
-               if (!name)
+               id = get_id(src, src_type, i);
+               if (!id)
                        continue;
-               dst = set_name(dst, dst_type, offset + i,
-                                       isl_name_copy(dst->ctx, name));
+               dst = set_id(dst, dst_type, offset + i, isl_id_copy(id));
                if (!dst)
                        return NULL;
        }
@@ -183,13 +210,28 @@ static struct isl_dim *copy_names(struct isl_dim *dst,
 struct isl_dim *isl_dim_dup(struct isl_dim *dim)
 {
        struct isl_dim *dup;
+       if (!dim)
+               return NULL;
        dup = isl_dim_alloc(dim->ctx, dim->nparam, dim->n_in, dim->n_out);
-       if (!dim->names)
+       if (dim->tuple_id[0] &&
+           !(dup->tuple_id[0] = isl_id_copy(dim->tuple_id[0])))
+               goto error;
+       if (dim->tuple_id[1] &&
+           !(dup->tuple_id[1] = isl_id_copy(dim->tuple_id[1])))
+               goto error;
+       if (dim->nested[0] && !(dup->nested[0] = isl_dim_copy(dim->nested[0])))
+               goto error;
+       if (dim->nested[1] && !(dup->nested[1] = isl_dim_copy(dim->nested[1])))
+               goto error;
+       if (!dim->ids)
                return dup;
-       dup = copy_names(dup, isl_dim_param, 0, dim, isl_dim_param);
-       dup = copy_names(dup, isl_dim_in, 0, dim, isl_dim_in);
-       dup = copy_names(dup, isl_dim_out, 0, dim, isl_dim_out);
+       dup = copy_ids(dup, isl_dim_param, 0, dim, isl_dim_param);
+       dup = copy_ids(dup, isl_dim_in, 0, dim, isl_dim_in);
+       dup = copy_ids(dup, isl_dim_out, 0, dim, isl_dim_out);
        return dup;
+error:
+       isl_dim_free(dup);
+       return NULL;
 }
 
 struct isl_dim *isl_dim_cow(struct isl_dim *dim)
@@ -222,25 +264,149 @@ void isl_dim_free(struct isl_dim *dim)
        if (--dim->ref > 0)
                return;
 
-       for (i = 0; i < dim->n_name; ++i)
-               isl_name_free(dim->ctx, dim->names[i]);
-       free(dim->names);
+       isl_id_free(dim->tuple_id[0]);
+       isl_id_free(dim->tuple_id[1]);
+
+       isl_dim_free(dim->nested[0]);
+       isl_dim_free(dim->nested[1]);
+
+       for (i = 0; i < dim->n_id; ++i)
+               isl_id_free(dim->ids[i]);
+       free(dim->ids);
        isl_ctx_deref(dim->ctx);
        
        free(dim);
 }
 
+static int name_ok(isl_ctx *ctx, const char *s)
+{
+       char *p;
+       long dummy;
+
+       dummy = strtol(s, &p, 0);
+       if (p != s)
+               isl_die(ctx, isl_error_invalid, "name looks like a number",
+                       return 0);
+
+       return 1;
+}
+
+__isl_give isl_id *isl_dim_get_tuple_id(__isl_keep isl_dim *dim,
+       enum isl_dim_type type)
+{
+       if (!dim)
+               return NULL;
+       if (type != isl_dim_in && type != isl_dim_out)
+               return NULL;
+       return isl_id_copy(dim->tuple_id[type - isl_dim_in]);
+}
+
+__isl_give isl_dim *isl_dim_set_tuple_id(__isl_take isl_dim *dim,
+       enum isl_dim_type type, __isl_take isl_id *id)
+{
+       dim = isl_dim_cow(dim);
+       if (!dim || !id)
+               goto error;
+       if (type != isl_dim_in && type != isl_dim_out)
+               isl_die(dim->ctx, isl_error_invalid,
+                       "only input, output and set tuples can have names",
+                       goto error);
+
+       isl_id_free(dim->tuple_id[type - isl_dim_in]);
+       dim->tuple_id[type - isl_dim_in] = id;
+
+       return dim;
+error:
+       isl_id_free(id);
+       isl_dim_free(dim);
+       return NULL;
+}
+
+__isl_give isl_dim *isl_dim_reset_tuple_id(__isl_take isl_dim *dim,
+       enum isl_dim_type type)
+{
+       dim = isl_dim_cow(dim);
+       if (!dim)
+               return NULL;
+       if (type != isl_dim_in && type != isl_dim_out)
+               isl_die(dim->ctx, isl_error_invalid,
+                       "only input, output and set tuples can have names",
+                       goto error);
+
+       isl_id_free(dim->tuple_id[type - isl_dim_in]);
+       dim->tuple_id[type - isl_dim_in] = NULL;
+
+       return dim;
+error:
+       isl_dim_free(dim);
+       return NULL;
+}
+
+__isl_give isl_dim *isl_dim_set_dim_id(__isl_take isl_dim *dim,
+       enum isl_dim_type type, unsigned pos, __isl_take isl_id *id)
+{
+       dim = isl_dim_cow(dim);
+       if (!dim || !id)
+               goto error;
+       isl_id_free(get_id(dim, type, pos));
+       return set_id(dim, type, pos, id);
+error:
+       isl_id_free(id);
+       isl_dim_free(dim);
+       return NULL;
+}
+
+__isl_give isl_id *isl_dim_get_dim_id(__isl_keep isl_dim *dim,
+       enum isl_dim_type type, unsigned pos)
+{
+       return isl_id_copy(get_id(dim, type, pos));
+}
+
+__isl_give isl_dim *isl_dim_set_tuple_name(__isl_take isl_dim *dim,
+       enum isl_dim_type type, const char *s)
+{
+       isl_id *id;
+
+       if (!dim)
+               return NULL;
+
+       if (!s)
+               return isl_dim_reset_tuple_id(dim, type);
+
+       if (!name_ok(dim->ctx, s))
+               goto error;
+
+       id = isl_id_alloc(dim->ctx, s, NULL);
+       return isl_dim_set_tuple_id(dim, type, id);
+error:
+       isl_dim_free(dim);
+       return NULL;
+}
+
+const char *isl_dim_get_tuple_name(__isl_keep isl_dim *dim,
+        enum isl_dim_type type)
+{
+       isl_id *id;
+       if (!dim)
+               return NULL;
+       if (type != isl_dim_in && type != isl_dim_out)
+               return NULL;
+       id = dim->tuple_id[type - isl_dim_in];
+       return id ? id->name : NULL;
+}
+
 struct isl_dim *isl_dim_set_name(struct isl_dim *dim,
                                 enum isl_dim_type type, unsigned pos,
                                 const char *s)
 {
-       struct isl_name *name;
+       isl_id *id;
+
        if (!dim)
                return NULL;
-       name = isl_name_get(dim->ctx, s);
-       if (!name)
+       if (!name_ok(dim->ctx, s))
                goto error;
-       return set_name(dim, type, pos, name);
+       id = isl_id_alloc(dim->ctx, s, NULL);
+       return isl_dim_set_dim_id(dim, type, pos, id);
 error:
        isl_dim_free(dim);
        return NULL;
@@ -249,8 +415,74 @@ error:
 const char *isl_dim_get_name(struct isl_dim *dim,
                                 enum isl_dim_type type, unsigned pos)
 {
-       struct isl_name *name = get_name(dim, type, pos);
-       return name ? name->name : NULL;
+       isl_id *id = get_id(dim, type, pos);
+       return id ? id->name : NULL;
+}
+
+int isl_dim_find_dim_by_id(__isl_keep isl_dim *dim, enum isl_dim_type type,
+       __isl_keep isl_id *id)
+{
+       int i;
+       int offset;
+       int n;
+
+       if (!dim || !id)
+               return -1;
+
+       offset = isl_dim_offset(dim, type);
+       n = isl_dim_size(dim, type);
+       for (i = 0; i < n && offset + i < dim->n_id; ++i)
+               if (dim->ids[offset + i] == id)
+                       return i;
+
+       return -1;
+}
+
+static __isl_keep isl_id *tuple_id(__isl_keep isl_dim *dim,
+       enum isl_dim_type type)
+{
+       if (!dim)
+               return NULL;
+       if (type == isl_dim_in)
+               return dim->tuple_id[0];
+       if (type == isl_dim_out)
+               return dim->tuple_id[1];
+       return NULL;
+}
+
+static __isl_keep isl_dim *nested(__isl_keep isl_dim *dim,
+       enum isl_dim_type type)
+{
+       if (!dim)
+               return NULL;
+       if (type == isl_dim_in)
+               return dim->nested[0];
+       if (type == isl_dim_out)
+               return dim->nested[1];
+       return NULL;
+}
+
+int isl_dim_tuple_match(__isl_keep isl_dim *dim1, enum isl_dim_type dim1_type,
+                       __isl_keep isl_dim *dim2, enum isl_dim_type dim2_type)
+{
+       isl_id *id1, *id2;
+       isl_dim *nested1, *nested2;
+
+       if (n(dim1, dim1_type) != n(dim2, dim2_type))
+               return 0;
+       id1 = tuple_id(dim1, dim1_type);
+       id2 = tuple_id(dim2, dim2_type);
+       if (!id1 ^ !id2)
+               return 0;
+       if (id1 && id1 != id2)
+               return 0;
+       nested1 = nested(dim1, dim1_type);
+       nested2 = nested(dim2, dim2_type);
+       if (!nested1 ^ !nested2)
+               return 0;
+       if (nested1 && !isl_dim_equal(nested1, nested2))
+               return 0;
+       return 1;
 }
 
 static int match(struct isl_dim *dim1, enum isl_dim_type dim1_type,
@@ -258,15 +490,14 @@ static int match(struct isl_dim *dim1, enum isl_dim_type dim1_type,
 {
        int i;
 
-       if (n(dim1, dim1_type) != n(dim2, dim2_type))
+       if (!isl_dim_tuple_match(dim1, dim1_type, dim2, dim2_type))
                return 0;
 
-       if (!dim1->names && !dim2->names)
+       if (!dim1->ids && !dim2->ids)
                return 1;
 
        for (i = 0; i < n(dim1, dim1_type); ++i) {
-               if (get_name(dim1, dim1_type, i) !=
-                   get_name(dim2, dim2_type, i))
+               if (get_id(dim1, dim1_type, i) != get_id(dim2, dim2_type, i))
                        return 0;
        }
        return 1;
@@ -278,19 +509,19 @@ int isl_dim_match(struct isl_dim *dim1, enum isl_dim_type dim1_type,
        return match(dim1, dim1_type, dim2, dim2_type);
 }
 
-static void get_names(struct isl_dim *dim, enum isl_dim_type type,
-       unsigned first, unsigned n, struct isl_name **names)
+static void get_ids(struct isl_dim *dim, enum isl_dim_type type,
+       unsigned first, unsigned n, __isl_keep isl_id **ids)
 {
        int i;
 
        for (i = 0; i < n ; ++i)
-               names[i] = get_name(dim, type, first+i);
+               ids[i] = get_id(dim, type, first + i);
 }
 
 struct isl_dim *isl_dim_extend(struct isl_dim *dim,
                        unsigned nparam, unsigned n_in, unsigned n_out)
 {
-       struct isl_name **names = NULL;
+       isl_id **ids = NULL;
 
        if (!dim)
                return NULL;
@@ -303,18 +534,17 @@ struct isl_dim *isl_dim_extend(struct isl_dim *dim,
 
        dim = isl_dim_cow(dim);
 
-       if (dim->names) {
-               names = isl_calloc_array(dim->ctx, struct isl_name *,
+       if (dim->ids) {
+               ids = isl_calloc_array(dim->ctx, isl_id *,
                                         nparam + n_in + n_out);
-               if (!names)
+               if (!ids)
                        goto error;
-               get_names(dim, isl_dim_param, 0, dim->nparam, names);
-               get_names(dim, isl_dim_in, 0, dim->n_in, names + nparam);
-               get_names(dim, isl_dim_out, 0, dim->n_out,
-                               names + nparam + n_in);
-               free(dim->names);
-               dim->names = names;
-               dim->n_name = nparam + n_in + n_out;
+               get_ids(dim, isl_dim_param, 0, dim->nparam, ids);
+               get_ids(dim, isl_dim_in, 0, dim->n_in, ids + nparam);
+               get_ids(dim, isl_dim_out, 0, dim->n_out, ids + nparam + n_in);
+               free(dim->ids);
+               dim->ids = ids;
+               dim->n_id = nparam + n_in + n_out;
        }
        dim->nparam = nparam;
        dim->n_in = n_in;
@@ -322,7 +552,7 @@ struct isl_dim *isl_dim_extend(struct isl_dim *dim,
 
        return dim;
 error:
-       free(names);
+       free(ids);
        isl_dim_free(dim);
        return NULL;
 }
@@ -330,41 +560,78 @@ error:
 struct isl_dim *isl_dim_add(struct isl_dim *dim, enum isl_dim_type type,
        unsigned n)
 {
+       if (!dim)
+               return NULL;
+       dim = isl_dim_reset(dim, type);
        switch (type) {
        case isl_dim_param:
-               return isl_dim_extend(dim,
+               dim = isl_dim_extend(dim,
                                        dim->nparam + n, dim->n_in, dim->n_out);
+               if (dim && dim->nested[0] &&
+                   !(dim->nested[0] = isl_dim_add(dim->nested[0],
+                                                   isl_dim_param, n)))
+                       goto error;
+               if (dim && dim->nested[1] &&
+                   !(dim->nested[1] = isl_dim_add(dim->nested[1],
+                                                   isl_dim_param, n)))
+                       goto error;
+               return dim;
        case isl_dim_in:
                return isl_dim_extend(dim,
                                        dim->nparam, dim->n_in + n, dim->n_out);
        case isl_dim_out:
                return isl_dim_extend(dim,
                                        dim->nparam, dim->n_in, dim->n_out + n);
+       default:
+               isl_die(dim->ctx, isl_error_invalid,
+                       "cannot add dimensions of specified type", goto error);
+       }
+error:
+       isl_dim_free(dim);
+       return NULL;
+}
+
+static int valid_dim_type(enum isl_dim_type type)
+{
+       switch (type) {
+       case isl_dim_param:
+       case isl_dim_in:
+       case isl_dim_out:
+               return 1;
+       default:
+               return 0;
        }
-       return dim;
 }
 
 __isl_give isl_dim *isl_dim_insert(__isl_take isl_dim *dim,
        enum isl_dim_type type, unsigned pos, unsigned n)
 {
-       struct isl_name **names = NULL;
+       isl_id **ids = NULL;
 
        if (!dim)
                return NULL;
        if (n == 0)
-               return dim;
+               return isl_dim_reset(dim, type);
+
+       if (!valid_dim_type(type))
+               isl_die(dim->ctx, isl_error_invalid,
+                       "cannot insert dimensions of specified type",
+                       goto error);
 
        isl_assert(dim->ctx, pos <= isl_dim_size(dim, type), goto error);
 
        dim = isl_dim_cow(dim);
+       if (!dim)
+               return NULL;
 
-       if (dim->names) {
+       if (dim->ids) {
                enum isl_dim_type t;
                int off;
-               int size[3];
-               names = isl_calloc_array(dim->ctx, struct isl_name *,
+               int s[3];
+               int *size = s - isl_dim_param;
+               ids = isl_calloc_array(dim->ctx, isl_id *,
                                     dim->nparam + dim->n_in + dim->n_out + n);
-               if (!names)
+               if (!ids)
                        goto error;
                off = 0;
                size[isl_dim_param] = dim->nparam;
@@ -372,24 +639,26 @@ __isl_give isl_dim *isl_dim_insert(__isl_take isl_dim *dim,
                size[isl_dim_out] = dim->n_out;
                for (t = isl_dim_param; t <= isl_dim_out; ++t) {
                        if (t != type) {
-                               get_names(dim, t, 0, size[t], names + off);
+                               get_ids(dim, t, 0, size[t], ids + off);
                                off += size[t];
                        } else {
-                               get_names(dim, t, 0, pos, names + off);
+                               get_ids(dim, t, 0, pos, ids + off);
                                off += pos + n;
-                               get_names(dim, t, pos, size[t]-pos, names+off);
+                               get_ids(dim, t, pos, size[t] - pos, ids + off);
                                off += size[t] - pos;
                        }
                }
-               free(dim->names);
-               dim->names = names;
-               dim->n_name = dim->nparam + dim->n_in + dim->n_out + n;
+               free(dim->ids);
+               dim->ids = ids;
+               dim->n_id = dim->nparam + dim->n_in + dim->n_out + n;
        }
        switch (type) {
        case isl_dim_param:     dim->nparam += n; break;
        case isl_dim_in:        dim->n_in += n; break;
        case isl_dim_out:       dim->n_out += n; break;
+       default:                ;
        }
+       dim = isl_dim_reset(dim, type);
 
        return dim;
 error:
@@ -401,6 +670,8 @@ __isl_give isl_dim *isl_dim_move(__isl_take isl_dim *dim,
        enum isl_dim_type dst_type, unsigned dst_pos,
        enum isl_dim_type src_type, unsigned src_pos, unsigned n)
 {
+       int i;
+
        if (!dim)
                return NULL;
        if (n == 0)
@@ -409,29 +680,81 @@ __isl_give isl_dim *isl_dim_move(__isl_take isl_dim *dim,
        isl_assert(dim->ctx, src_pos + n <= isl_dim_size(dim, src_type),
                goto error);
 
-       /* just the simple case for now */
-       isl_assert(dim->ctx,
-               offset(dim, dst_type) + dst_pos ==
-               offset(dim, src_type) + src_pos + ((src_type < dst_type) ? n : 0),
-               goto error);
-
-       if (dst_type == src_type)
+       if (dst_type == src_type && dst_pos == src_pos)
                return dim;
 
+       isl_assert(dim->ctx, dst_type != src_type, goto error);
+
+       dim = isl_dim_reset(dim, src_type);
+       dim = isl_dim_reset(dim, dst_type);
+
        dim = isl_dim_cow(dim);
        if (!dim)
                return NULL;
 
+       if (dim->ids) {
+               isl_id **ids;
+               enum isl_dim_type t;
+               int off;
+               int s[3];
+               int *size = s - isl_dim_param;
+               ids = isl_calloc_array(dim->ctx, isl_id *,
+                                        dim->nparam + dim->n_in + dim->n_out);
+               if (!ids)
+                       goto error;
+               off = 0;
+               size[isl_dim_param] = dim->nparam;
+               size[isl_dim_in] = dim->n_in;
+               size[isl_dim_out] = dim->n_out;
+               for (t = isl_dim_param; t <= isl_dim_out; ++t) {
+                       if (t == dst_type) {
+                               get_ids(dim, t, 0, dst_pos, ids + off);
+                               off += dst_pos;
+                               get_ids(dim, src_type, src_pos, n, ids + off);
+                               off += n;
+                               get_ids(dim, t, dst_pos, size[t] - dst_pos,
+                                               ids + off);
+                               off += size[t] - dst_pos;
+                       } else if (t == src_type) {
+                               get_ids(dim, t, 0, src_pos, ids + off);
+                               off += src_pos;
+                               get_ids(dim, t, src_pos + n,
+                                           size[t] - src_pos - n, ids + off);
+                               off += size[t] - src_pos - n;
+                       } else {
+                               get_ids(dim, t, 0, size[t], ids + off);
+                               off += size[t];
+                       }
+               }
+               free(dim->ids);
+               dim->ids = ids;
+               dim->n_id = dim->nparam + dim->n_in + dim->n_out;
+       }
+
        switch (dst_type) {
        case isl_dim_param:     dim->nparam += n; break;
        case isl_dim_in:        dim->n_in += n; break;
        case isl_dim_out:       dim->n_out += n; break;
+       default:                ;
        }
 
        switch (src_type) {
        case isl_dim_param:     dim->nparam -= n; break;
        case isl_dim_in:        dim->n_in -= n; break;
        case isl_dim_out:       dim->n_out -= n; break;
+       default:                ;
+       }
+
+       if (dst_type != isl_dim_param && src_type != isl_dim_param)
+               return dim;
+
+       for (i = 0; i < 2; ++i) {
+               if (!dim->nested[i])
+                       continue;
+               dim->nested[i] = isl_dim_replace(dim->nested[i],
+                                                isl_dim_param, dim);
+               if (!dim->nested[i])
+                       goto error;
        }
 
        return dim;
@@ -449,16 +772,30 @@ struct isl_dim *isl_dim_join(struct isl_dim *left, struct isl_dim *right)
 
        isl_assert(left->ctx, match(left, isl_dim_param, right, isl_dim_param),
                        goto error);
-       isl_assert(left->ctx, n(left, isl_dim_out) == n(right, isl_dim_in),
-                       goto error);
+       isl_assert(left->ctx,
+               isl_dim_tuple_match(left, isl_dim_out, right, isl_dim_in),
+               goto error);
 
        dim = isl_dim_alloc(left->ctx, left->nparam, left->n_in, right->n_out);
        if (!dim)
                goto error;
 
-       dim = copy_names(dim, isl_dim_param, 0, left, isl_dim_param);
-       dim = copy_names(dim, isl_dim_in, 0, left, isl_dim_in);
-       dim = copy_names(dim, isl_dim_out, 0, right, isl_dim_out);
+       dim = copy_ids(dim, isl_dim_param, 0, left, isl_dim_param);
+       dim = copy_ids(dim, isl_dim_in, 0, left, isl_dim_in);
+       dim = copy_ids(dim, isl_dim_out, 0, right, isl_dim_out);
+
+       if (dim && left->tuple_id[0] &&
+           !(dim->tuple_id[0] = isl_id_copy(left->tuple_id[0])))
+               goto error;
+       if (dim && right->tuple_id[1] &&
+           !(dim->tuple_id[1] = isl_id_copy(right->tuple_id[1])))
+               goto error;
+       if (dim && left->nested[0] &&
+           !(dim->nested[0] = isl_dim_copy(left->nested[0])))
+               goto error;
+       if (dim && right->nested[1] &&
+           !(dim->nested[1] = isl_dim_copy(right->nested[1])))
+               goto error;
 
        isl_dim_free(left);
        isl_dim_free(right);
@@ -472,7 +809,7 @@ error:
 
 struct isl_dim *isl_dim_product(struct isl_dim *left, struct isl_dim *right)
 {
-       struct isl_dim *dim;
+       isl_dim *dom1, *dom2, *nest1, *nest2;
 
        if (!left || !right)
                goto error;
@@ -480,67 +817,92 @@ struct isl_dim *isl_dim_product(struct isl_dim *left, struct isl_dim *right)
        isl_assert(left->ctx, match(left, isl_dim_param, right, isl_dim_param),
                        goto error);
 
-       dim = isl_dim_alloc(left->ctx, left->nparam,
-                       left->n_in + right->n_in, left->n_out + right->n_out);
-       if (!dim)
-               goto error;
+       dom1 = isl_dim_domain(isl_dim_copy(left));
+       dom2 = isl_dim_domain(isl_dim_copy(right));
+       nest1 = isl_dim_wrap(isl_dim_join(isl_dim_reverse(dom1), dom2));
 
-       dim = copy_names(dim, isl_dim_param, 0, left, isl_dim_param);
-       dim = copy_names(dim, isl_dim_in, 0, left, isl_dim_in);
-       dim = copy_names(dim, isl_dim_in, left->n_in, right, isl_dim_in);
-       dim = copy_names(dim, isl_dim_out, 0, left, isl_dim_out);
-       dim = copy_names(dim, isl_dim_out, left->n_out, right, isl_dim_out);
+       dom1 = isl_dim_range(left);
+       dom2 = isl_dim_range(right);
+       nest2 = isl_dim_wrap(isl_dim_join(isl_dim_reverse(dom1), dom2));
 
+       return isl_dim_join(isl_dim_reverse(nest1), nest2);
+error:
        isl_dim_free(left);
        isl_dim_free(right);
+       return NULL;
+}
 
-       return dim;
+__isl_give isl_dim *isl_dim_range_product(__isl_take isl_dim *left,
+       __isl_take isl_dim *right)
+{
+       isl_dim *dom, *ran1, *ran2, *nest;
+
+       if (!left || !right)
+               goto error;
+
+       isl_assert(left->ctx, match(left, isl_dim_param, right, isl_dim_param),
+                       goto error);
+       if (!isl_dim_match(left, isl_dim_in, right, isl_dim_in))
+               isl_die(left->ctx, isl_error_invalid,
+                       "domains need to match", goto error);
+
+       dom = isl_dim_domain(isl_dim_copy(left));
+
+       ran1 = isl_dim_range(left);
+       ran2 = isl_dim_range(right);
+       nest = isl_dim_wrap(isl_dim_join(isl_dim_reverse(ran1), ran2));
+
+       return isl_dim_join(isl_dim_reverse(dom), nest);
 error:
        isl_dim_free(left);
        isl_dim_free(right);
        return NULL;
 }
 
-struct isl_dim *isl_dim_map(struct isl_dim *dim)
+__isl_give isl_dim *isl_dim_map_from_set(__isl_take isl_dim *dim)
 {
-       struct isl_name **names = NULL;
+       isl_id **ids = NULL;
 
        if (!dim)
                return NULL;
        isl_assert(dim->ctx, dim->n_in == 0, goto error);
-       if (dim->n_out == 0)
+       if (dim->n_out == 0 && !isl_dim_is_named_or_nested(dim, isl_dim_out))
                return dim;
        dim = isl_dim_cow(dim);
        if (!dim)
                return NULL;
-       if (dim->names) {
-               names = isl_calloc_array(dim->ctx, struct isl_name *,
+       if (dim->ids) {
+               ids = isl_calloc_array(dim->ctx, isl_id *,
                                        dim->nparam + dim->n_out + dim->n_out);
-               if (!names)
+               if (!ids)
                        goto error;
-               get_names(dim, isl_dim_param, 0, dim->nparam, names);
-               get_names(dim, isl_dim_out, 0, dim->n_out, names + dim->nparam);
+               get_ids(dim, isl_dim_param, 0, dim->nparam, ids);
+               get_ids(dim, isl_dim_out, 0, dim->n_out, ids + dim->nparam);
        }
        dim->n_in = dim->n_out;
-       if (names) {
-               free(dim->names);
-               dim->names = names;
-               dim->n_name = dim->nparam + dim->n_out + dim->n_out;
-               dim = copy_names(dim, isl_dim_out, 0, dim, isl_dim_in);
+       if (ids) {
+               free(dim->ids);
+               dim->ids = ids;
+               dim->n_id = dim->nparam + dim->n_out + dim->n_out;
+               dim = copy_ids(dim, isl_dim_out, 0, dim, isl_dim_in);
        }
+       isl_id_free(dim->tuple_id[0]);
+       dim->tuple_id[0] = isl_id_copy(dim->tuple_id[1]);
+       isl_dim_free(dim->nested[0]);
+       dim->nested[0] = isl_dim_copy(dim->nested[1]);
        return dim;
 error:
        isl_dim_free(dim);
        return NULL;
 }
 
-static struct isl_dim *set_names(struct isl_dim *dim, enum isl_dim_type type,
-       unsigned first, unsigned n, struct isl_name **names)
+static __isl_give isl_dim *set_ids(struct isl_dim *dim, enum isl_dim_type type,
+       unsigned first, unsigned n, __isl_take isl_id **ids)
 {
        int i;
 
        for (i = 0; i < n ; ++i)
-               dim = set_name(dim, type, first+i, names[i]);
+               dim = set_id(dim, type, first + i, ids[i]);
 
        return dim;
 }
@@ -548,7 +910,9 @@ static struct isl_dim *set_names(struct isl_dim *dim, enum isl_dim_type type,
 struct isl_dim *isl_dim_reverse(struct isl_dim *dim)
 {
        unsigned t;
-       struct isl_name **names = NULL;
+       isl_dim *nested;
+       isl_id **ids = NULL;
+       isl_id *id;
 
        if (!dim)
                return NULL;
@@ -559,28 +923,36 @@ struct isl_dim *isl_dim_reverse(struct isl_dim *dim)
        if (!dim)
                return NULL;
 
-       if (dim->names) {
-               names = isl_alloc_array(dim->ctx, struct isl_name *,
+       id = dim->tuple_id[0];
+       dim->tuple_id[0] = dim->tuple_id[1];
+       dim->tuple_id[1] = id;
+
+       nested = dim->nested[0];
+       dim->nested[0] = dim->nested[1];
+       dim->nested[1] = nested;
+
+       if (dim->ids) {
+               ids = isl_alloc_array(dim->ctx, isl_id *,
                                        dim->n_in + dim->n_out);
-               if (!names)
+               if (!ids)
                        goto error;
-               get_names(dim, isl_dim_in, 0, dim->n_in, names);
-               get_names(dim, isl_dim_out, 0, dim->n_out, names + dim->n_in);
+               get_ids(dim, isl_dim_in, 0, dim->n_in, ids);
+               get_ids(dim, isl_dim_out, 0, dim->n_out, ids + dim->n_in);
        }
 
        t = dim->n_in;
        dim->n_in = dim->n_out;
        dim->n_out = t;
 
-       if (dim->names) {
-               dim = set_names(dim, isl_dim_out, 0, dim->n_out, names);
-               dim = set_names(dim, isl_dim_in, 0, dim->n_in, names + dim->n_out);
-               free(names);
+       if (dim->ids) {
+               dim = set_ids(dim, isl_dim_out, 0, dim->n_out, ids);
+               dim = set_ids(dim, isl_dim_in, 0, dim->n_in, ids + dim->n_out);
+               free(ids);
        }
 
        return dim;
 error:
-       free(names);
+       free(ids);
        isl_dim_free(dim);
        return NULL;
 }
@@ -593,37 +965,53 @@ struct isl_dim *isl_dim_drop(struct isl_dim *dim, enum isl_dim_type type,
        if (!dim)
                return NULL;
 
-       if (n == 0)
-               return dim;
+       if (num == 0)
+               return isl_dim_reset(dim, type);
+
+       if (!valid_dim_type(type))
+               isl_die(dim->ctx, isl_error_invalid,
+                       "cannot drop dimensions of specified type", goto error);
 
        isl_assert(dim->ctx, first + num <= n(dim, type), goto error);
        dim = isl_dim_cow(dim);
        if (!dim)
                goto error;
-       if (dim->names) {
-               dim = extend_names(dim);
+       if (dim->ids) {
+               dim = extend_ids(dim);
                if (!dim)
                        goto error;
                for (i = 0; i < num; ++i)
-                       isl_name_free(dim->ctx, get_name(dim, type, first+i));
+                       isl_id_free(get_id(dim, type, first + i));
                for (i = first+num; i < n(dim, type); ++i)
-                       set_name(dim, type, i - num, get_name(dim, type, i));
+                       set_id(dim, type, i - num, get_id(dim, type, i));
                switch (type) {
                case isl_dim_param:
-                       get_names(dim, isl_dim_in, 0, dim->n_in,
-                               dim->names + offset(dim, isl_dim_in) - num);
+                       get_ids(dim, isl_dim_in, 0, dim->n_in,
+                               dim->ids + offset(dim, isl_dim_in) - num);
                case isl_dim_in:
-                       get_names(dim, isl_dim_out, 0, dim->n_out,
-                               dim->names + offset(dim, isl_dim_out) - num);
-               case isl_dim_out:
+                       get_ids(dim, isl_dim_out, 0, dim->n_out,
+                               dim->ids + offset(dim, isl_dim_out) - num);
+               default:
                        ;
                }
-               dim->n_name -= num;
+               dim->n_id -= num;
        }
        switch (type) {
        case isl_dim_param:     dim->nparam -= num; break;
        case isl_dim_in:        dim->n_in -= num; break;
        case isl_dim_out:       dim->n_out -= num; break;
+       default:                ;
+       }
+       dim = isl_dim_reset(dim, type);
+       if (type == isl_dim_param) {
+               if (dim && dim->nested[0] &&
+                   !(dim->nested[0] = isl_dim_drop(dim->nested[0],
+                                                   isl_dim_param, first, num)))
+                       goto error;
+               if (dim && dim->nested[1] &&
+                   !(dim->nested[1] = isl_dim_drop(dim->nested[1],
+                                                   isl_dim_param, first, num)))
+                       goto error;
        }
        return dim;
 error:
@@ -634,12 +1022,16 @@ error:
 struct isl_dim *isl_dim_drop_inputs(struct isl_dim *dim,
                unsigned first, unsigned n)
 {
+       if (!dim)
+               return NULL;
        return isl_dim_drop(dim, isl_dim_in, first, n);
 }
 
 struct isl_dim *isl_dim_drop_outputs(struct isl_dim *dim,
                unsigned first, unsigned n)
 {
+       if (!dim)
+               return NULL;
        return isl_dim_drop(dim, isl_dim_out, first, n);
 }
 
@@ -651,6 +1043,11 @@ struct isl_dim *isl_dim_domain(struct isl_dim *dim)
        return isl_dim_reverse(dim);
 }
 
+__isl_give isl_dim *isl_dim_from_domain(__isl_take isl_dim *dim)
+{
+       return isl_dim_reverse(dim);
+}
+
 struct isl_dim *isl_dim_range(struct isl_dim *dim)
 {
        if (!dim)
@@ -658,6 +1055,25 @@ struct isl_dim *isl_dim_range(struct isl_dim *dim)
        return isl_dim_drop_inputs(dim, 0, dim->n_in);
 }
 
+__isl_give isl_dim *isl_dim_from_range(__isl_take isl_dim *dim)
+{
+       return dim;
+}
+
+__isl_give isl_dim *isl_dim_as_set_dim(__isl_take isl_dim *dim)
+{
+       dim = isl_dim_cow(dim);
+       if (!dim)
+               return NULL;
+
+       dim->n_out += dim->n_in;
+       dim->n_in = 0;
+       dim = isl_dim_reset(dim, isl_dim_in);
+       dim = isl_dim_reset(dim, isl_dim_out);
+
+       return dim;
+}
+
 struct isl_dim *isl_dim_underlying(struct isl_dim *dim, unsigned n_div)
 {
        int i;
@@ -665,8 +1081,8 @@ struct isl_dim *isl_dim_underlying(struct isl_dim *dim, unsigned n_div)
        if (!dim)
                return NULL;
        if (n_div == 0 &&
-           dim->nparam == 0 && dim->n_in == 0 && dim->n_name == 0)
-               return dim;
+           dim->nparam == 0 && dim->n_in == 0 && dim->n_id == 0)
+               return isl_dim_reset(isl_dim_reset(dim, isl_dim_in), isl_dim_out);
        dim = isl_dim_cow(dim);
        if (!dim)
                return NULL;
@@ -674,23 +1090,25 @@ struct isl_dim *isl_dim_underlying(struct isl_dim *dim, unsigned n_div)
        dim->nparam = 0;
        dim->n_in = 0;
 
-       for (i = 0; i < dim->n_name; ++i)
-               isl_name_free(dim->ctx, get_name(dim, isl_dim_out, i));
-       dim->n_name = 0;
+       for (i = 0; i < dim->n_id; ++i)
+               isl_id_free(get_id(dim, isl_dim_out, i));
+       dim->n_id = 0;
+       dim = isl_dim_reset(dim, isl_dim_in);
+       dim = isl_dim_reset(dim, isl_dim_out);
 
        return dim;
 }
 
 unsigned isl_dim_total(struct isl_dim *dim)
 {
-       return dim->nparam + dim->n_in + dim->n_out;
+       return dim ? dim->nparam + dim->n_in + dim->n_out : 0;
 }
 
 int isl_dim_equal(struct isl_dim *dim1, struct isl_dim *dim2)
 {
        return match(dim1, isl_dim_param, dim2, isl_dim_param) &&
-              n(dim1, isl_dim_in) == n(dim2, isl_dim_in) &&
-              n(dim1, isl_dim_out) == n(dim2, isl_dim_out);
+              isl_dim_tuple_match(dim1, isl_dim_in, dim2, isl_dim_in) &&
+              isl_dim_tuple_match(dim1, isl_dim_out, dim2, isl_dim_out);
 }
 
 int isl_dim_compatible(struct isl_dim *dim1, struct isl_dim *dim2)
@@ -698,3 +1116,302 @@ int isl_dim_compatible(struct isl_dim *dim1, struct isl_dim *dim2)
        return dim1->nparam == dim2->nparam &&
               dim1->n_in + dim1->n_out == dim2->n_in + dim2->n_out;
 }
+
+static uint32_t isl_hash_dim(uint32_t hash, __isl_keep isl_dim *dim)
+{
+       int i;
+       isl_id *id;
+
+       if (!dim)
+               return hash;
+
+       hash = isl_hash_builtin(hash, dim->nparam);
+       hash = isl_hash_builtin(hash, dim->n_in);
+       hash = isl_hash_builtin(hash, dim->n_out);
+
+       for (i = 0; i < dim->nparam; ++i) {
+               id = get_id(dim, isl_dim_param, i);
+               hash = isl_hash_id(hash, id);
+       }
+
+       id = tuple_id(dim, isl_dim_in);
+       hash = isl_hash_id(hash, id);
+       id = tuple_id(dim, isl_dim_out);
+       hash = isl_hash_id(hash, id);
+
+       hash = isl_hash_dim(hash, dim->nested[0]);
+       hash = isl_hash_dim(hash, dim->nested[1]);
+
+       return hash;
+}
+
+uint32_t isl_dim_get_hash(__isl_keep isl_dim *dim)
+{
+       uint32_t hash;
+
+       if (!dim)
+               return 0;
+
+       hash = isl_hash_init();
+       hash = isl_hash_dim(hash, dim);
+
+       return hash;
+}
+
+int isl_dim_is_wrapping(__isl_keep isl_dim *dim)
+{
+       if (!dim)
+               return -1;
+
+       if (dim->n_in != 0 || dim->tuple_id[0] || dim->nested[0])
+               return 0;
+
+       return dim->nested[1] != NULL;
+}
+
+__isl_give isl_dim *isl_dim_wrap(__isl_take isl_dim *dim)
+{
+       isl_dim *wrap;
+
+       if (!dim)
+               return NULL;
+
+       wrap = isl_dim_alloc(dim->ctx, dim->nparam, 0, dim->n_in + dim->n_out);
+
+       wrap = copy_ids(wrap, isl_dim_param, 0, dim, isl_dim_param);
+       wrap = copy_ids(wrap, isl_dim_set, 0, dim, isl_dim_in);
+       wrap = copy_ids(wrap, isl_dim_set, dim->n_in, dim, isl_dim_out);
+
+       if (!wrap)
+               goto error;
+
+       wrap->nested[1] = dim;
+
+       return wrap;
+error:
+       isl_dim_free(dim);
+       return NULL;
+}
+
+__isl_give isl_dim *isl_dim_unwrap(__isl_take isl_dim *dim)
+{
+       isl_dim *unwrap;
+
+       if (!dim)
+               return NULL;
+
+       if (!isl_dim_is_wrapping(dim))
+               isl_die(dim->ctx, isl_error_invalid, "not a wrapping dim",
+                       goto error);
+
+       unwrap = isl_dim_copy(dim->nested[1]);
+       isl_dim_free(dim);
+
+       return unwrap;
+error:
+       isl_dim_free(dim);
+       return NULL;
+}
+
+int isl_dim_is_named_or_nested(__isl_keep isl_dim *dim, enum isl_dim_type type)
+{
+       if (type != isl_dim_in && type != isl_dim_out)
+               return 0;
+       if (!dim)
+               return -1;
+       if (dim->tuple_id[type - isl_dim_in])
+               return 1;
+       if (dim->nested[type - isl_dim_in])
+               return 1;
+       return 0;
+}
+
+int isl_dim_may_be_set(__isl_keep isl_dim *dim)
+{
+       if (!dim)
+               return -1;
+       if (isl_dim_size(dim, isl_dim_in) != 0)
+               return 0;
+       if (isl_dim_is_named_or_nested(dim, isl_dim_in))
+               return 0;
+       return 1;
+}
+
+__isl_give isl_dim *isl_dim_reset(__isl_take isl_dim *dim,
+       enum isl_dim_type type)
+{
+       if (!isl_dim_is_named_or_nested(dim, type))
+               return dim;
+
+       dim = isl_dim_cow(dim);
+       if (!dim)
+               return NULL;
+
+       isl_id_free(dim->tuple_id[type - isl_dim_in]);
+       dim->tuple_id[type - isl_dim_in] = NULL;
+       isl_dim_free(dim->nested[type - isl_dim_in]);
+       dim->nested[type - isl_dim_in] = NULL;
+
+       return dim;
+}
+
+__isl_give isl_dim *isl_dim_flatten(__isl_take isl_dim *dim)
+{
+       if (!dim)
+               return NULL;
+       if (!dim->nested[0] && !dim->nested[1])
+               return dim;
+
+       if (dim->nested[0])
+               dim = isl_dim_reset(dim, isl_dim_in);
+       if (dim && dim->nested[1])
+               dim = isl_dim_reset(dim, isl_dim_out);
+
+       return dim;
+}
+
+__isl_give isl_dim *isl_dim_flatten_range(__isl_take isl_dim *dim)
+{
+       if (!dim)
+               return NULL;
+       if (!dim->nested[1])
+               return dim;
+
+       return isl_dim_reset(dim, isl_dim_out);
+}
+
+/* Replace the dimensions of the given type of dst by those of src.
+ */
+__isl_give isl_dim *isl_dim_replace(__isl_take isl_dim *dst,
+       enum isl_dim_type type, __isl_keep isl_dim *src)
+{
+       dst = isl_dim_cow(dst);
+
+       if (!dst || !src)
+               goto error;
+
+       dst = isl_dim_drop(dst, type, 0, isl_dim_size(dst, type));
+       dst = isl_dim_add(dst, type, isl_dim_size(src, type));
+       dst = copy_ids(dst, type, 0, src, type);
+
+       if (dst && type == isl_dim_param) {
+               int i;
+               for (i = 0; i <= 1; ++i) {
+                       if (!dst->nested[i])
+                               continue;
+                       dst->nested[i] = isl_dim_replace(dst->nested[i],
+                                                        type, src);
+                       if (!dst->nested[i])
+                               goto error;
+               }
+       }
+
+       return dst;
+error:
+       isl_dim_free(dst);
+       return NULL;
+}
+
+/* Given a dimension specification "dim" of a set, create a dimension
+ * specification for the lift of the set.  In particular, the result
+ * is of the form [dim -> local[..]], with n_local variables in the
+ * range of the wrapped map.
+ */
+__isl_give isl_dim *isl_dim_lift(__isl_take isl_dim *dim, unsigned n_local)
+{
+       isl_dim *local_dim;
+
+       if (!dim)
+               return NULL;
+
+       local_dim = isl_dim_dup(dim);
+       local_dim = isl_dim_drop(local_dim, isl_dim_set, 0, dim->n_out);
+       local_dim = isl_dim_add(local_dim, isl_dim_set, n_local);
+       local_dim = isl_dim_set_tuple_name(local_dim, isl_dim_set, "local");
+       dim = isl_dim_join(isl_dim_from_domain(dim),
+                           isl_dim_from_range(local_dim));
+       dim = isl_dim_wrap(dim);
+       dim = isl_dim_set_tuple_name(dim, isl_dim_set, "lifted");
+
+       return dim;
+}
+
+int isl_dim_can_zip(__isl_keep isl_dim *dim)
+{
+       if (!dim)
+               return -1;
+
+       return dim->nested[0] && dim->nested[1];
+}
+
+__isl_give isl_dim *isl_dim_zip(__isl_take isl_dim *dim)
+{
+       isl_dim *dom, *ran;
+       isl_dim *dom_dom, *dom_ran, *ran_dom, *ran_ran;
+
+       if (!isl_dim_can_zip(dim))
+               isl_die(dim->ctx, isl_error_invalid, "dim cannot be zipped",
+                       goto error);
+
+       if (!dim)
+               return 0;
+       dom = isl_dim_unwrap(isl_dim_domain(isl_dim_copy(dim)));
+       ran = isl_dim_unwrap(isl_dim_range(dim));
+       dom_dom = isl_dim_domain(isl_dim_copy(dom));
+       dom_ran = isl_dim_range(dom);
+       ran_dom = isl_dim_domain(isl_dim_copy(ran));
+       ran_ran = isl_dim_range(ran);
+       dom = isl_dim_join(isl_dim_from_domain(dom_dom),
+                          isl_dim_from_range(ran_dom));
+       ran = isl_dim_join(isl_dim_from_domain(dom_ran),
+                          isl_dim_from_range(ran_ran));
+       return isl_dim_join(isl_dim_from_domain(isl_dim_wrap(dom)),
+                           isl_dim_from_range(isl_dim_wrap(ran)));
+error:
+       isl_dim_free(dim);
+       return NULL;
+}
+
+int isl_dim_has_named_params(__isl_keep isl_dim *dim)
+{
+       int i;
+       unsigned off;
+
+       if (!dim)
+               return -1;
+       if (dim->nparam == 0)
+               return 1;
+       off = isl_dim_offset(dim, isl_dim_param);
+       if (off + dim->nparam > dim->n_id)
+               return 0;
+       for (i = 0; i < dim->nparam; ++i)
+               if (!dim->ids[off + i])
+                       return 0;
+       return 1;
+}
+
+/* Align the initial parameters of dim1 to match the order in dim2.
+ */
+__isl_give isl_dim *isl_dim_align_params(__isl_take isl_dim *dim1,
+       __isl_take isl_dim *dim2)
+{
+       isl_reordering *exp;
+
+       if (!isl_dim_has_named_params(dim1) || !isl_dim_has_named_params(dim2))
+               isl_die(isl_dim_get_ctx(dim1), isl_error_invalid,
+                       "parameter alignment requires named parameters",
+                       goto error);
+
+       exp = isl_parameter_alignment_reordering(dim1, dim2);
+       isl_dim_free(dim1);
+       isl_dim_free(dim2);
+       if (!exp)
+               return NULL;
+       dim1 = isl_dim_copy(exp->dim);
+       isl_reordering_free(exp);
+       return dim1;
+error:
+       isl_dim_free(dim1);
+       isl_dim_free(dim2);
+       return NULL;
+}