1 files changed, 26 insertions, 7 deletions

diff --git a/src/H5Spoint.c b/src/H5Spoint.c
index c58e7a7..6cb5d9b 100644
--- a/src/H5Spoint.c
+++ b/src/H5Spoint.c
@@ -843,6 +843,10 @@ H5S__copy_pnt_list(const H5S_pnt_list_t *src, unsigned rank)
     H5MM_memcpy(dst->high_bounds, src->high_bounds, (rank * sizeof(hsize_t)));
     H5MM_memcpy(dst->low_bounds, src->low_bounds, (rank * sizeof(hsize_t)));
 
+    /* Clear cached iteration point */
+    dst->last_idx = 0;
+    dst->last_idx_pnt = NULL;
+
     /* Set return value */
     ret_value = dst;
 
@@ -1511,6 +1515,7 @@ done:
 static herr_t
 H5S__get_select_elem_pointlist(const H5S_t *space, hsize_t startpoint, hsize_t numpoints, hsize_t *buf)
 {
+    const hsize_t   endpoint = startpoint + numpoints; /* Index of last point in iteration */
     H5S_pnt_node_t *node; /* Point node */
     unsigned        rank; /* Dataspace rank */
 
@@ -1522,14 +1527,20 @@ H5S__get_select_elem_pointlist(const H5S_t *space, hsize_t startpoint, hsize_t n
     /* Get the dataspace extent rank */
     rank = space->extent.rank;
 
-    /* Get the head of the point list */
-    node = space->select.sel_info.pnt_lst->head;
+    /* Check for cached point at the correct index */
+    if(space->select.sel_info.pnt_lst->last_idx_pnt
+            && startpoint == space->select.sel_info.pnt_lst->last_idx)
+        node = space->select.sel_info.pnt_lst->last_idx_pnt;
+    else {
+        /* Get the head of the point list */
+        node = space->select.sel_info.pnt_lst->head;
 
-    /* Iterate to the first point to return */
-    while (node != NULL && startpoint > 0) {
-        startpoint--;
-        node = node->next;
-    } /* end while */
+        /* Iterate to the first point to return */
+        while (node != NULL && startpoint > 0) {
+            startpoint--;
+            node = node->next;
+        } /* end while */
+    } /* end else */
 
     /* Iterate through the node, copying each point's information */
     while (node != NULL && numpoints > 0) {
@@ -1539,6 +1550,10 @@ H5S__get_select_elem_pointlist(const H5S_t *space, hsize_t startpoint, hsize_t n
         node = node->next;
     } /* end while */
 
+    /* Cached next point in iteration */
+    space->select.sel_info.pnt_lst->last_idx = endpoint;
+    space->select.sel_info.pnt_lst->last_idx_pnt = node;
+
     FUNC_LEAVE_NOAPI(SUCCEED)
 } /* end H5S__get_select_elem_pointlist() */
 
@@ -2331,6 +2346,10 @@ H5S__point_project_simple(const H5S_t *base_space, H5S_t *new_space, hsize_t *of
         } /* end for */
     }     /* end else */
 
+    /* Clear cached iteration point */
+    new_space->select.sel_info.pnt_lst->last_idx = 0;
+    new_space->select.sel_info.pnt_lst->last_idx_pnt = NULL;
+
     /* Number of elements selected will be the same */
     new_space->select.num_elem = base_space->select.num_elem;