Merge branch 'develop' into feature/coding_standardsfeature/coding_standards

1 files changed, 286 insertions, 109 deletions

diff --git a/src/H5Dselect.c b/src/H5Dselect.c
index a843d93..1a6292c 100644
--- a/src/H5Dselect.c
+++ b/src/H5Dselect.c
@@ -6,12 +6,12 @@
  * This file is part of HDF5.  The full HDF5 copyright notice, including     *
  * terms governing use, modification, and redistribution, is contained in    *
  * the COPYING file, which can be found at the root of the source code       *
- * distribution tree, or in https://support.hdfgroup.org/ftp/HDF5/releases.  *
+ * distribution tree, or in https://www.hdfgroup.org/licenses.               *
  * If you do not have access to either file, you may request a copy from     *
  * help@hdfgroup.org.                                                        *
  * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
 
-/* Programmer:  Quincey Koziol <koziol@ncsa.uiuc.ued>
+/* Programmer:  Quincey Koziol
  *              Thursday, September 30, 2004
  *
  * Purpose:	Dataspace I/O functions.
@@ -21,42 +21,36 @@
 /* Module Setup */
 /****************/
 
-#include "H5Dmodule.h"          /* This source code file is part of the H5D module */
-
+#include "H5Dmodule.h" /* This source code file is part of the H5D module */
 
 /***********/
 /* Headers */
 /***********/
-#include "H5private.h"		/* Generic Functions			*/
-#include "H5CXprivate.h"        /* API Contexts                         */
-#include "H5Dpkg.h"		/* Datasets				*/
-#include "H5Eprivate.h"		/* Error handling		  	*/
-#include "H5FLprivate.h"	/* Free Lists                           */
-
+#include "H5private.h"   /* Generic Functions			*/
+#include "H5CXprivate.h" /* API Contexts                         */
+#include "H5Dpkg.h"      /* Datasets				*/
+#include "H5Eprivate.h"  /* Error handling		  	*/
+#include "H5FLprivate.h" /* Free Lists                           */
 
 /****************/
 /* Local Macros */
 /****************/
 
-
 /******************/
 /* Local Typedefs */
 /******************/
 
-
 /********************/
 /* Local Prototypes */
 /********************/
 
-static herr_t H5D__select_io(const H5D_io_info_t *io_info, size_t elmt_size,
-    size_t nelmts, const H5S_t *file_space, const H5S_t *mem_space);
-
+static herr_t H5D__select_io(const H5D_io_info_t *io_info, size_t elmt_size, size_t nelmts, H5S_t *file_space,
+                             H5S_t *mem_space);
 
 /*********************/
 /* Package Variables */
 /*********************/
 
-
 /*******************/
 /* Local Variables */
 /*******************/
@@ -70,8 +64,6 @@ H5FL_SEQ_DEFINE(hsize_t);
 /* Declare extern free list to manage the H5S_sel_iter_t struct */
 H5FL_EXTERN(H5S_sel_iter_t);
 
-
-
 /*-------------------------------------------------------------------------
  * Function:	H5D__select_io
  *
@@ -85,27 +77,27 @@ H5FL_EXTERN(H5S_sel_iter_t);
  *-------------------------------------------------------------------------
  */
 static herr_t
-H5D__select_io(const H5D_io_info_t *io_info, size_t elmt_size,
-    size_t nelmts, const H5S_t *file_space, const H5S_t *mem_space)
+H5D__select_io(const H5D_io_info_t *io_info, size_t elmt_size, size_t nelmts, H5S_t *file_space,
+               H5S_t *mem_space)
 {
-    H5S_sel_iter_t *mem_iter = NULL; /* Memory selection iteration info */
-    hbool_t mem_iter_init = FALSE; /* Memory selection iteration info has been initialized */
-    H5S_sel_iter_t *file_iter = NULL; /* File selection iteration info */
-    hbool_t file_iter_init = FALSE; /* File selection iteration info has been initialized */
-    hsize_t *mem_off = NULL;    /* Pointer to sequence offsets in memory */
-    hsize_t *file_off = NULL;   /* Pointer to sequence offsets in the file */
-    size_t *mem_len = NULL;     /* Pointer to sequence lengths in memory */
-    size_t *file_len = NULL;    /* Pointer to sequence lengths in the file */
-    size_t curr_mem_seq;        /* Current memory sequence to operate on */
-    size_t curr_file_seq;       /* Current file sequence to operate on */
-    size_t mem_nseq;            /* Number of sequences generated in the file */
-    size_t file_nseq;           /* Number of sequences generated in memory */
-    size_t dxpl_vec_size;       /* Vector length from API context's DXPL */
-    size_t vec_size;            /* Vector length */
-    ssize_t tmp_file_len;       /* Temporary number of bytes in file sequence */
-    herr_t ret_value = SUCCEED; /* Return value */
+    H5S_sel_iter_t *mem_iter       = NULL;  /* Memory selection iteration info */
+    hbool_t         mem_iter_init  = FALSE; /* Memory selection iteration info has been initialized */
+    H5S_sel_iter_t *file_iter      = NULL;  /* File selection iteration info */
+    hbool_t         file_iter_init = FALSE; /* File selection iteration info has been initialized */
+    hsize_t *       mem_off        = NULL;  /* Pointer to sequence offsets in memory */
+    hsize_t *       file_off       = NULL;  /* Pointer to sequence offsets in the file */
+    size_t *        mem_len        = NULL;  /* Pointer to sequence lengths in memory */
+    size_t *        file_len       = NULL;  /* Pointer to sequence lengths in the file */
+    size_t          curr_mem_seq;           /* Current memory sequence to operate on */
+    size_t          curr_file_seq;          /* Current file sequence to operate on */
+    size_t          mem_nseq;               /* Number of sequences generated in the file */
+    size_t          file_nseq;              /* Number of sequences generated in memory */
+    size_t          dxpl_vec_size;          /* Vector length from API context's DXPL */
+    size_t          vec_size;               /* Vector length */
+    ssize_t         tmp_file_len;           /* Temporary number of bytes in file sequence */
+    herr_t          ret_value = SUCCEED;    /* Return value */
 
-    FUNC_ENTER_STATIC
+    FUNC_ENTER_PACKAGE
 
     /* Check args */
     HDassert(io_info);
@@ -113,51 +105,41 @@ H5D__select_io(const H5D_io_info_t *io_info, size_t elmt_size,
     HDassert(io_info->store);
     HDassert(io_info->u.rbuf);
 
-    /* Get info from API context */
-    if(H5CX_get_vec_size(&dxpl_vec_size) < 0)
-        HGOTO_ERROR(H5E_DATASET, H5E_CANTGET, FAIL, "can't retrieve I/O vector size")
-
-    /* Allocate the vector I/O arrays */
-    if(dxpl_vec_size > H5D_IO_VECTOR_SIZE)
-        vec_size = dxpl_vec_size;
-    else
-        vec_size = H5D_IO_VECTOR_SIZE;
-    if(NULL == (mem_len = H5FL_SEQ_MALLOC(size_t, vec_size)))
-        HGOTO_ERROR(H5E_DATASET, H5E_CANTALLOC, FAIL, "can't allocate I/O length vector array")
-    if(NULL == (mem_off = H5FL_SEQ_MALLOC(hsize_t, vec_size)))
-        HGOTO_ERROR(H5E_DATASET, H5E_CANTALLOC, FAIL, "can't allocate I/O offset vector array")
-    if(NULL == (file_len = H5FL_SEQ_MALLOC(size_t, vec_size)))
-        HGOTO_ERROR(H5E_DATASET, H5E_CANTALLOC, FAIL, "can't allocate I/O length vector array")
-    if(NULL == (file_off = H5FL_SEQ_MALLOC(hsize_t, vec_size)))
-        HGOTO_ERROR(H5E_DATASET, H5E_CANTALLOC, FAIL, "can't allocate I/O offset vector array")
+    if (elmt_size == 0)
+        HGOTO_ERROR(H5E_DATASPACE, H5E_BADVALUE, FAIL, "invalid elmt_size of 0")
 
     /* Check for only one element in selection */
-    if(nelmts == 1) {
+    if (nelmts == 1) {
+        hsize_t single_mem_off;  /* Offset in memory */
+        hsize_t single_file_off; /* Offset in the file */
+        size_t  single_mem_len;  /* Length in memory */
+        size_t  single_file_len; /* Length in the file */
+
         /* Get offset of first element in selections */
-        if(H5S_SELECT_OFFSET(file_space, file_off) < 0)
+        if (H5S_SELECT_OFFSET(file_space, &single_file_off) < 0)
             HGOTO_ERROR(H5E_INTERNAL, H5E_UNSUPPORTED, FAIL, "can't retrieve file selection offset")
-        if(H5S_SELECT_OFFSET(mem_space, mem_off) < 0)
+        if (H5S_SELECT_OFFSET(mem_space, &single_mem_off) < 0)
             HGOTO_ERROR(H5E_INTERNAL, H5E_UNSUPPORTED, FAIL, "can't retrieve memory selection offset")
 
         /* Set up necessary information for I/O operation */
         file_nseq = mem_nseq = 1;
         curr_mem_seq = curr_file_seq = 0;
-        *file_off *= elmt_size;
-        *mem_off *= elmt_size;
-        *file_len = *mem_len = elmt_size;
+        single_file_off *= elmt_size;
+        single_mem_off *= elmt_size;
+        single_file_len = single_mem_len = elmt_size;
 
         /* Perform I/O on memory and file sequences */
-        if(io_info->op_type == H5D_IO_OP_READ) {
-            if((tmp_file_len = (*io_info->layout_ops.readvv)(io_info,
-                    file_nseq, &curr_file_seq, file_len, file_off,
-                    mem_nseq, &curr_mem_seq, mem_len, mem_off)) < 0)
+        if (io_info->op_type == H5D_IO_OP_READ) {
+            if ((tmp_file_len = (*io_info->layout_ops.readvv)(
+                     io_info, file_nseq, &curr_file_seq, &single_file_len, &single_file_off, mem_nseq,
+                     &curr_mem_seq, &single_mem_len, &single_mem_off)) < 0)
                 HGOTO_ERROR(H5E_DATASPACE, H5E_READERROR, FAIL, "read error")
         } /* end if */
         else {
             HDassert(io_info->op_type == H5D_IO_OP_WRITE);
-            if((tmp_file_len = (*io_info->layout_ops.writevv)(io_info,
-                    file_nseq, &curr_file_seq, file_len, file_off,
-                    mem_nseq, &curr_mem_seq, mem_len, mem_off)) < 0)
+            if ((tmp_file_len = (*io_info->layout_ops.writevv)(
+                     io_info, file_nseq, &curr_file_seq, &single_file_len, &single_file_off, mem_nseq,
+                     &curr_mem_seq, &single_mem_len, &single_mem_off)) < 0)
                 HGOTO_ERROR(H5E_DATASPACE, H5E_WRITEERROR, FAIL, "write error")
         } /* end else */
 
@@ -165,35 +147,54 @@ H5D__select_io(const H5D_io_info_t *io_info, size_t elmt_size,
         HDassert(((size_t)tmp_file_len % elmt_size) == 0);
     } /* end if */
     else {
-        size_t mem_nelem;           /* Number of elements used in memory sequences */
-        size_t file_nelem;          /* Number of elements used in file sequences */
+        size_t mem_nelem;  /* Number of elements used in memory sequences */
+        size_t file_nelem; /* Number of elements used in file sequences */
+
+        /* Get info from API context */
+        if (H5CX_get_vec_size(&dxpl_vec_size) < 0)
+            HGOTO_ERROR(H5E_DATASET, H5E_CANTGET, FAIL, "can't retrieve I/O vector size")
+
+        /* Allocate the vector I/O arrays */
+        if (dxpl_vec_size > H5D_IO_VECTOR_SIZE)
+            vec_size = dxpl_vec_size;
+        else
+            vec_size = H5D_IO_VECTOR_SIZE;
+        if (NULL == (mem_len = H5FL_SEQ_MALLOC(size_t, vec_size)))
+            HGOTO_ERROR(H5E_DATASET, H5E_CANTALLOC, FAIL, "can't allocate I/O length vector array")
+        if (NULL == (mem_off = H5FL_SEQ_MALLOC(hsize_t, vec_size)))
+            HGOTO_ERROR(H5E_DATASET, H5E_CANTALLOC, FAIL, "can't allocate I/O offset vector array")
+        if (NULL == (file_len = H5FL_SEQ_MALLOC(size_t, vec_size)))
+            HGOTO_ERROR(H5E_DATASET, H5E_CANTALLOC, FAIL, "can't allocate I/O length vector array")
+        if (NULL == (file_off = H5FL_SEQ_MALLOC(hsize_t, vec_size)))
+            HGOTO_ERROR(H5E_DATASET, H5E_CANTALLOC, FAIL, "can't allocate I/O offset vector array")
 
         /* Allocate the iterators */
-        if(NULL == (mem_iter = H5FL_MALLOC(H5S_sel_iter_t)))
+        if (NULL == (mem_iter = H5FL_MALLOC(H5S_sel_iter_t)))
             HGOTO_ERROR(H5E_DATASET, H5E_CANTALLOC, FAIL, "can't allocate memory iterator")
-        if(NULL == (file_iter = H5FL_MALLOC(H5S_sel_iter_t)))
+        if (NULL == (file_iter = H5FL_MALLOC(H5S_sel_iter_t)))
             HGOTO_ERROR(H5E_DATASET, H5E_CANTALLOC, FAIL, "can't allocate file iterator")
 
         /* Initialize file iterator */
-        if(H5S_select_iter_init(file_iter, file_space, elmt_size, H5S_SEL_ITER_GET_SEQ_LIST_SORTED) < 0)
+        if (H5S_select_iter_init(file_iter, file_space, elmt_size, H5S_SEL_ITER_GET_SEQ_LIST_SORTED) < 0)
             HGOTO_ERROR(H5E_DATASPACE, H5E_CANTINIT, FAIL, "unable to initialize selection iterator")
-        file_iter_init = 1;	/* File selection iteration info has been initialized */
+        file_iter_init = 1; /* File selection iteration info has been initialized */
 
         /* Initialize memory iterator */
-        if(H5S_select_iter_init(mem_iter, mem_space, elmt_size, 0) < 0)
+        if (H5S_select_iter_init(mem_iter, mem_space, elmt_size, 0) < 0)
             HGOTO_ERROR(H5E_DATASPACE, H5E_CANTINIT, FAIL, "unable to initialize selection iterator")
-        mem_iter_init = 1;	/* Memory selection iteration info has been initialized */
+        mem_iter_init = 1; /* Memory selection iteration info has been initialized */
 
         /* Initialize sequence counts */
         curr_mem_seq = curr_file_seq = 0;
         mem_nseq = file_nseq = 0;
 
         /* Loop, until all bytes are processed */
-        while(nelmts > 0) {
+        while (nelmts > 0) {
             /* Check if more file sequences are needed */
-            if(curr_file_seq >= file_nseq) {
+            if (curr_file_seq >= file_nseq) {
                 /* Get sequences for file selection */
-                if(H5S_SELECT_ITER_GET_SEQ_LIST(file_iter, vec_size, nelmts, &file_nseq, &file_nelem, file_off, file_len) < 0)
+                if (H5S_SELECT_ITER_GET_SEQ_LIST(file_iter, vec_size, nelmts, &file_nseq, &file_nelem,
+                                                 file_off, file_len) < 0)
                     HGOTO_ERROR(H5E_INTERNAL, H5E_UNSUPPORTED, FAIL, "sequence length generation failed")
 
                 /* Start at the beginning of the sequences again */
@@ -201,9 +202,10 @@ H5D__select_io(const H5D_io_info_t *io_info, size_t elmt_size,
             } /* end if */
 
             /* Check if more memory sequences are needed */
-            if(curr_mem_seq >= mem_nseq) {
+            if (curr_mem_seq >= mem_nseq) {
                 /* Get sequences for memory selection */
-                if(H5S_SELECT_ITER_GET_SEQ_LIST(mem_iter, vec_size, nelmts, &mem_nseq, &mem_nelem, mem_off, mem_len) < 0)
+                if (H5S_SELECT_ITER_GET_SEQ_LIST(mem_iter, vec_size, nelmts, &mem_nseq, &mem_nelem, mem_off,
+                                                 mem_len) < 0)
                     HGOTO_ERROR(H5E_INTERNAL, H5E_UNSUPPORTED, FAIL, "sequence length generation failed")
 
                 /* Start at the beginning of the sequences again */
@@ -211,53 +213,232 @@ H5D__select_io(const H5D_io_info_t *io_info, size_t elmt_size,
             } /* end if */
 
             /* Perform I/O on memory and file sequences */
-            if(io_info->op_type == H5D_IO_OP_READ) {
-                if((tmp_file_len = (*io_info->layout_ops.readvv)(io_info,
-                        file_nseq, &curr_file_seq, file_len, file_off,
-                        mem_nseq, &curr_mem_seq, mem_len, mem_off)) < 0)
+            if (io_info->op_type == H5D_IO_OP_READ) {
+                if ((tmp_file_len =
+                         (*io_info->layout_ops.readvv)(io_info, file_nseq, &curr_file_seq, file_len, file_off,
+                                                       mem_nseq, &curr_mem_seq, mem_len, mem_off)) < 0)
                     HGOTO_ERROR(H5E_DATASPACE, H5E_READERROR, FAIL, "read error")
             } /* end if */
             else {
                 HDassert(io_info->op_type == H5D_IO_OP_WRITE);
-                if((tmp_file_len = (*io_info->layout_ops.writevv)(io_info,
-                        file_nseq, &curr_file_seq, file_len, file_off,
-                        mem_nseq, &curr_mem_seq, mem_len, mem_off)) < 0)
+                if ((tmp_file_len = (*io_info->layout_ops.writevv)(io_info, file_nseq, &curr_file_seq,
+                                                                   file_len, file_off, mem_nseq,
+                                                                   &curr_mem_seq, mem_len, mem_off)) < 0)
                     HGOTO_ERROR(H5E_DATASPACE, H5E_WRITEERROR, FAIL, "write error")
             } /* end else */
 
             /* Decrement number of elements left to process */
             HDassert(((size_t)tmp_file_len % elmt_size) == 0);
-            if(elmt_size == 0)
-                HGOTO_ERROR(H5E_DATASPACE, H5E_BADVALUE, FAIL, "Resulted in division by zero")
             nelmts -= ((size_t)tmp_file_len / elmt_size);
         } /* end while */
-    } /* end else */
+    }     /* end else */
 
 done:
     /* Release selection iterators */
-    if(file_iter_init && H5S_SELECT_ITER_RELEASE(file_iter) < 0)
+    if (file_iter_init && H5S_SELECT_ITER_RELEASE(file_iter) < 0)
         HDONE_ERROR(H5E_DATASET, H5E_CANTRELEASE, FAIL, "unable to release selection iterator")
-    if(file_iter)
+    if (file_iter)
         file_iter = H5FL_FREE(H5S_sel_iter_t, file_iter);
-    if(mem_iter_init && H5S_SELECT_ITER_RELEASE(mem_iter) < 0)
+    if (mem_iter_init && H5S_SELECT_ITER_RELEASE(mem_iter) < 0)
         HDONE_ERROR(H5E_DATASET, H5E_CANTRELEASE, FAIL, "unable to release selection iterator")
-    if(mem_iter)
+    if (mem_iter)
         mem_iter = H5FL_FREE(H5S_sel_iter_t, mem_iter);
 
     /* Release vector arrays, if allocated */
-    if(file_len)
+    if (file_len)
         file_len = H5FL_SEQ_FREE(size_t, file_len);
-    if(file_off)
+    if (file_off)
         file_off = H5FL_SEQ_FREE(hsize_t, file_off);
-    if(mem_len)
+    if (mem_len)
         mem_len = H5FL_SEQ_FREE(size_t, mem_len);
-    if(mem_off)
+    if (mem_off)
         mem_off = H5FL_SEQ_FREE(hsize_t, mem_off);
 
     FUNC_LEAVE_NOAPI(ret_value)
 } /* end H5D__select_io() */
 
-
+/*-------------------------------------------------------------------------
+ * Function:    H5D_select_io_mem
+ *
+ * Purpose:     Perform memory copies directly between two memory buffers
+ *              according to the selections in the `dst_space` and
+ *              `src_space` dataspaces.
+ *
+ * Note:        This routine is [basically] the same as H5D__select_io,
+ *              with the only difference being that the readvv/writevv
+ *              calls are exchanged for H5VM_memcpyvv calls. Changes should
+ *              be made to both routines.
+ *
+ * Return:      Non-negative on success/Negative on failure
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5D_select_io_mem(void *dst_buf, const H5S_t *dst_space, const void *src_buf, const H5S_t *src_space,
+                  size_t elmt_size, size_t nelmts)
+{
+    H5S_sel_iter_t *dst_sel_iter      = NULL;  /* Destination dataspace iteration info */
+    H5S_sel_iter_t *src_sel_iter      = NULL;  /* Source dataspace iteration info */
+    hbool_t         dst_sel_iter_init = FALSE; /* Destination dataspace selection iterator initialized? */
+    hbool_t         src_sel_iter_init = FALSE; /* Source dataspace selection iterator initialized? */
+    hsize_t *       dst_off           = NULL;  /* Pointer to sequence offsets in destination buffer */
+    hsize_t *       src_off           = NULL;  /* Pointer to sequence offsets in source buffer */
+    size_t *        dst_len           = NULL;  /* Pointer to sequence lengths in destination buffer */
+    size_t *        src_len           = NULL;  /* Pointer to sequence lengths in source buffer */
+    size_t          curr_dst_seq;              /* Current destination buffer sequence to operate on */
+    size_t          curr_src_seq;              /* Current source buffer sequence to operate on */
+    size_t          dst_nseq;                  /* Number of sequences generated for destination buffer */
+    size_t          src_nseq;                  /* Number of sequences generated for source buffer */
+    size_t          dxpl_vec_size;             /* Vector length from API context's DXPL */
+    size_t          vec_size;                  /* Vector length */
+    ssize_t         bytes_copied;
+    herr_t          ret_value = SUCCEED;
+
+    FUNC_ENTER_NOAPI(FAIL)
+
+    HDassert(dst_buf);
+    HDassert(dst_space);
+    HDassert(src_buf);
+    HDassert(src_space);
+
+    if (elmt_size == 0)
+        HGOTO_ERROR(H5E_DATASPACE, H5E_BADVALUE, FAIL, "invalid elmt_size of 0")
+
+    /* Check for only one element in selection */
+    if (nelmts == 1) {
+        hsize_t single_dst_off; /* Offset in dst_space */
+        hsize_t single_src_off; /* Offset in src_space */
+        size_t  single_dst_len; /* Length in dst_space */
+        size_t  single_src_len; /* Length in src_space */
+
+        /* Get offset of first element in selections */
+        if (H5S_SELECT_OFFSET(dst_space, &single_dst_off) < 0)
+            HGOTO_ERROR(H5E_DATASPACE, H5E_CANTGET, FAIL, "can't retrieve destination selection offset")
+        if (H5S_SELECT_OFFSET(src_space, &single_src_off) < 0)
+            HGOTO_ERROR(H5E_DATASPACE, H5E_CANTGET, FAIL, "can't retrieve source selection offset")
+
+        /* Set up necessary information for I/O operation */
+        dst_nseq = src_nseq = 1;
+        curr_dst_seq = curr_src_seq = 0;
+        single_dst_off *= elmt_size;
+        single_src_off *= elmt_size;
+        single_dst_len = single_src_len = elmt_size;
+
+        /* Perform vectorized memcpy from src_buf to dst_buf */
+        if ((bytes_copied =
+                 H5VM_memcpyvv(dst_buf, dst_nseq, &curr_dst_seq, &single_dst_len, &single_dst_off, src_buf,
+                               src_nseq, &curr_src_seq, &single_src_len, &single_src_off)) < 0)
+            HGOTO_ERROR(H5E_IO, H5E_WRITEERROR, FAIL, "vectorized memcpy failed")
+
+        HDassert(((size_t)bytes_copied % elmt_size) == 0);
+    }
+    else {
+        unsigned sel_iter_flags = H5S_SEL_ITER_GET_SEQ_LIST_SORTED | H5S_SEL_ITER_SHARE_WITH_DATASPACE;
+        size_t   dst_nelem; /* Number of elements used in destination buffer sequences */
+        size_t   src_nelem; /* Number of elements used in source buffer sequences */
+
+        /* Get info from API context */
+        if (H5CX_get_vec_size(&dxpl_vec_size) < 0)
+            HGOTO_ERROR(H5E_IO, H5E_CANTGET, FAIL, "can't retrieve I/O vector size")
+
+        /* Allocate the vector I/O arrays */
+        if (dxpl_vec_size > H5D_IO_VECTOR_SIZE)
+            vec_size = dxpl_vec_size;
+        else
+            vec_size = H5D_IO_VECTOR_SIZE;
+
+        if (NULL == (dst_len = H5FL_SEQ_MALLOC(size_t, vec_size)))
+            HGOTO_ERROR(H5E_IO, H5E_CANTALLOC, FAIL, "can't allocate I/O length vector array")
+        if (NULL == (dst_off = H5FL_SEQ_MALLOC(hsize_t, vec_size)))
+            HGOTO_ERROR(H5E_IO, H5E_CANTALLOC, FAIL, "can't allocate I/O offset vector array")
+        if (NULL == (src_len = H5FL_SEQ_MALLOC(size_t, vec_size)))
+            HGOTO_ERROR(H5E_IO, H5E_CANTALLOC, FAIL, "can't allocate I/O length vector array")
+        if (NULL == (src_off = H5FL_SEQ_MALLOC(hsize_t, vec_size)))
+            HGOTO_ERROR(H5E_IO, H5E_CANTALLOC, FAIL, "can't allocate I/O offset vector array")
+
+        /* Allocate the dataspace selection iterators */
+        if (NULL == (dst_sel_iter = H5FL_MALLOC(H5S_sel_iter_t)))
+            HGOTO_ERROR(H5E_DATASPACE, H5E_CANTALLOC, FAIL, "can't allocate destination selection iterator")
+        if (NULL == (src_sel_iter = H5FL_MALLOC(H5S_sel_iter_t)))
+            HGOTO_ERROR(H5E_DATASPACE, H5E_CANTALLOC, FAIL, "can't allocate source selection iterator")
+
+        /* Initialize destination selection iterator */
+        if (H5S_select_iter_init(dst_sel_iter, dst_space, elmt_size, sel_iter_flags) < 0)
+            HGOTO_ERROR(H5E_DATASPACE, H5E_CANTINIT, FAIL, "unable to initialize selection iterator")
+        dst_sel_iter_init = TRUE; /* Destination selection iteration info has been initialized */
+
+        /* Initialize source selection iterator */
+        if (H5S_select_iter_init(src_sel_iter, src_space, elmt_size, H5S_SEL_ITER_SHARE_WITH_DATASPACE) < 0)
+            HGOTO_ERROR(H5E_DATASPACE, H5E_CANTINIT, FAIL, "unable to initialize selection iterator")
+        src_sel_iter_init = TRUE; /* Source selection iteration info has been initialized */
+
+        /* Initialize sequence counts */
+        curr_dst_seq = curr_src_seq = 0;
+        dst_nseq = src_nseq = 0;
+
+        /* Loop, until all bytes are processed */
+        while (nelmts > 0) {
+            /* Check if more destination buffer sequences are needed */
+            if (curr_dst_seq >= dst_nseq) {
+                /* Get sequences for destination selection */
+                if (H5S_SELECT_ITER_GET_SEQ_LIST(dst_sel_iter, vec_size, nelmts, &dst_nseq, &dst_nelem,
+                                                 dst_off, dst_len) < 0)
+                    HGOTO_ERROR(H5E_DATASPACE, H5E_CANTGET, FAIL, "sequence length generation failed")
+
+                /* Start at the beginning of the sequences again */
+                curr_dst_seq = 0;
+            }
+
+            /* Check if more source buffer sequences are needed */
+            if (curr_src_seq >= src_nseq) {
+                /* Get sequences for source selection */
+                if (H5S_SELECT_ITER_GET_SEQ_LIST(src_sel_iter, vec_size, nelmts, &src_nseq, &src_nelem,
+                                                 src_off, src_len) < 0)
+                    HGOTO_ERROR(H5E_DATASPACE, H5E_CANTGET, FAIL, "sequence length generation failed")
+
+                /* Start at the beginning of the sequences again */
+                curr_src_seq = 0;
+            } /* end if */
+
+            /* Perform vectorized memcpy from src_buf to dst_buf */
+            if ((bytes_copied = H5VM_memcpyvv(dst_buf, dst_nseq, &curr_dst_seq, dst_len, dst_off, src_buf,
+                                              src_nseq, &curr_src_seq, src_len, src_off)) < 0)
+                HGOTO_ERROR(H5E_IO, H5E_WRITEERROR, FAIL, "vectorized memcpy failed")
+
+            /* Decrement number of elements left to process */
+            HDassert(((size_t)bytes_copied % elmt_size) == 0);
+            nelmts -= ((size_t)bytes_copied / elmt_size);
+        }
+    }
+
+done:
+    /* Release selection iterators */
+    if (src_sel_iter) {
+        if (src_sel_iter_init && H5S_SELECT_ITER_RELEASE(src_sel_iter) < 0)
+            HDONE_ERROR(H5E_DATASPACE, H5E_CANTRELEASE, FAIL, "unable to release selection iterator")
+
+        src_sel_iter = H5FL_FREE(H5S_sel_iter_t, src_sel_iter);
+    }
+    if (dst_sel_iter) {
+        if (dst_sel_iter_init && H5S_SELECT_ITER_RELEASE(dst_sel_iter) < 0)
+            HDONE_ERROR(H5E_DATASPACE, H5E_CANTRELEASE, FAIL, "unable to release selection iterator")
+
+        dst_sel_iter = H5FL_FREE(H5S_sel_iter_t, dst_sel_iter);
+    }
+
+    /* Release vector arrays, if allocated */
+    if (src_off)
+        src_off = H5FL_SEQ_FREE(hsize_t, src_off);
+    if (src_len)
+        src_len = H5FL_SEQ_FREE(size_t, src_len);
+    if (dst_off)
+        dst_off = H5FL_SEQ_FREE(hsize_t, dst_off);
+    if (dst_len)
+        dst_len = H5FL_SEQ_FREE(size_t, dst_len);
+
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5D_select_io_mem() */
+
 /*-------------------------------------------------------------------------
  * Function:	H5D__select_read
  *
@@ -271,8 +452,8 @@ done:
  *-------------------------------------------------------------------------
  */
 herr_t
-H5D__select_read(const H5D_io_info_t *io_info, const H5D_type_info_t *type_info,
-    hsize_t nelmts, const H5S_t *file_space, const H5S_t *mem_space)
+H5D__select_read(const H5D_io_info_t *io_info, const H5D_type_info_t *type_info, hsize_t nelmts,
+                 H5S_t *file_space, H5S_t *mem_space)
 {
     herr_t ret_value = SUCCEED; /* Return value */
 
@@ -280,15 +461,13 @@ H5D__select_read(const H5D_io_info_t *io_info, const H5D_type_info_t *type_info,
 
     /* Call generic selection operation */
     H5_CHECK_OVERFLOW(nelmts, hsize_t, size_t);
-    if(H5D__select_io(io_info, type_info->src_type_size, (size_t)nelmts,
-            file_space, mem_space) < 0)
+    if (H5D__select_io(io_info, type_info->src_type_size, (size_t)nelmts, file_space, mem_space) < 0)
         HGOTO_ERROR(H5E_DATASPACE, H5E_READERROR, FAIL, "read error")
 
 done:
     FUNC_LEAVE_NOAPI(ret_value)
 } /* end H5D__select_read() */
 
-
 /*-------------------------------------------------------------------------
  * Function:	H5D__select_write
  *
@@ -302,8 +481,8 @@ done:
  *-------------------------------------------------------------------------
  */
 herr_t
-H5D__select_write(const H5D_io_info_t *io_info, const H5D_type_info_t *type_info,
-    hsize_t nelmts, const H5S_t *file_space, const H5S_t *mem_space)
+H5D__select_write(const H5D_io_info_t *io_info, const H5D_type_info_t *type_info, hsize_t nelmts,
+                  H5S_t *file_space, H5S_t *mem_space)
 {
     herr_t ret_value = SUCCEED; /* Return value */
 
@@ -311,11 +490,9 @@ H5D__select_write(const H5D_io_info_t *io_info, const H5D_type_info_t *type_info
 
     /* Call generic selection operation */
     H5_CHECK_OVERFLOW(nelmts, hsize_t, size_t);
-    if(H5D__select_io(io_info, type_info->dst_type_size, (size_t)nelmts,
-            file_space, mem_space) < 0)
+    if (H5D__select_io(io_info, type_info->dst_type_size, (size_t)nelmts, file_space, mem_space) < 0)
         HGOTO_ERROR(H5E_DATASPACE, H5E_WRITEERROR, FAIL, "write error")
 
 done:
     FUNC_LEAVE_NOAPI(ret_value)
 } /* end H5D__select_write() */
-