// Creates a writeblock selection that only retrieves elements [start_elem, start_elem + num_elems)
// within a variable. An element is a single value of whatever the varaible's datatype is (i.e.,
// 1 element = 1 double if the variable type is double, 1 byte if the variable type is byte, etc.)
ADIOS_SELECTION * adios_selection_writeblock_bounded(int index, uint64_t start_elem, uint64_t num_elems, int is_timestep_relative) {
ADIOS_SELECTION *sel = common_read_selection_writeblock(index);
sel->u.block.is_absolute_index = !is_timestep_relative;
sel->u.block.is_sub_pg_selection = 1;
sel->u.block.element_offset = start_elem;
sel->u.block.nelements = num_elems;
return sel;
}
static int generate_read_request_for_pg(
const ADIOS_VARINFO *raw_varinfo, const ADIOS_TRANSINFO *transinfo,
const ADIOS_SELECTION *sel,
int timestep, int timestep_blockidx, int blockidx,
adios_transform_read_request *readreq)
{
const ADIOS_SELECTION *pg_bounds_sel;
ADIOS_SELECTION *pg_intersection_sel;
ADIOS_SELECTION *pg_writeblock_sel;
const ADIOS_VARBLOCK *raw_vb = &raw_varinfo->blockinfo[blockidx];
const ADIOS_VARBLOCK *orig_vb = &transinfo->orig_blockinfo[blockidx];
pg_bounds_sel = create_pg_bounds_from_varblock(transinfo->orig_ndim, orig_vb);
pg_writeblock_sel = common_read_selection_writeblock(blockidx);
pg_writeblock_sel->u.block.is_absolute_index = 1;
// Find the intersection, if any
if (is_global_selection(sel)) {
pg_intersection_sel = adios_selection_intersect_global(pg_bounds_sel, sel);
} else if (sel->type == ADIOS_SELECTION_WRITEBLOCK) {
pg_intersection_sel = adios_selection_intersect_local(pg_writeblock_sel, sel, timestep, raw_varinfo, transinfo);
} else {
abort(); // Should never be called with other types of selections
}
// If there is an intersection, generate a corresponding PG read request
if (pg_intersection_sel) {
// Make a PG read request group, and fill it with some subrequests, and link it into the read reqgroup
adios_transform_pg_read_request *new_pg_readreq;
new_pg_readreq = adios_transform_pg_read_request_new(timestep, timestep_blockidx, blockidx,
transinfo->orig_ndim, raw_varinfo->ndim,
orig_vb, raw_vb,
pg_intersection_sel, pg_bounds_sel,
transinfo->transform_metadatas[blockidx].content,
(uint16_t)transinfo->transform_metadatas[blockidx].length);
adios_transform_generate_read_subrequests(readreq, new_pg_readreq);
adios_transform_pg_read_request_append(readreq, new_pg_readreq);
// Don't free pg_bounds_sel or pg_intersection_sel, since they are now
// held by the adios_transform_pg_read_request struct
return 1;
} else {
// Cleanup
common_read_selection_delete((ADIOS_SELECTION *)pg_bounds_sel); // OK to delete, because this function only frees the outer struct, not the arrays within
return 0;
}
}
//
// One-on-one global intersection functions
//
ADIOS_SELECTION * adios_selection_intersect_wb_wb(const ADIOS_SELECTION_WRITEBLOCK_STRUCT *wb1,
const ADIOS_SELECTION_WRITEBLOCK_STRUCT *wb2,
int timestep,
const ADIOS_VARINFO *raw_varinfo, const ADIOS_TRANSINFO *transinfo)
{
int is_abs_idx;
int wbindex;
if (wb1->is_absolute_index == wb2->is_absolute_index) {
const int index1 = wb1->index;
const int index2 = wb2->index;
if (index1 != index2)
return NULL;
wbindex = index1;
is_abs_idx = wb1->is_absolute_index;
} else {
const int index1 = wb1->is_absolute_index ? wb1->index : adios_get_absolute_writeblock_index(raw_varinfo, wb1->index, timestep);
const int index2 = wb2->is_absolute_index ? wb2->index : adios_get_absolute_writeblock_index(raw_varinfo, wb2->index, timestep);
if (index1 != index2)
return NULL;
wbindex = index1;
is_abs_idx = 1;
}
if (!wb1->is_sub_pg_selection && !wb2->is_sub_pg_selection) {
// If neither selection is a sub-PG selection, the result is easy, and we can return immediately
ADIOS_SELECTION *inter_sel = common_read_selection_writeblock(wbindex);
inter_sel->u.block.is_absolute_index = is_abs_idx;
return inter_sel;
} else if (wb1->is_sub_pg_selection && wb2->is_sub_pg_selection) {
// Else, if both selections are sub-PG selections, take the overlapping portion (if any)
uint64_t inter_elem_offset, inter_nelems;
int intersects = intersect_segments(
wb1->element_offset, wb1->nelements,
wb2->element_offset, wb2->nelements,
&inter_elem_offset, &inter_nelems
);
if (intersects) {
ADIOS_SELECTION *inter_sel = common_read_selection_writeblock(wbindex);
inter_sel->u.block.is_absolute_index = is_abs_idx;
inter_sel->u.block.is_sub_pg_selection = 1;
inter_sel->u.block.element_offset = inter_elem_offset;
inter_sel->u.block.nelements = inter_nelems;
return inter_sel;
} else {
return NULL;
}
} else if (wb1->is_sub_pg_selection) {
// Else, if only the first selection is sub-PG, so just use its range
ADIOS_SELECTION *newwb = common_read_selection_writeblock(wb1->index);
newwb->u.block = *wb1;
return newwb;
} else if (wb2->is_sub_pg_selection) {
// Else, only the second selection is sub-PG, so just use its range
ADIOS_SELECTION *newwb = common_read_selection_writeblock(wb2->index);
newwb->u.block = *wb2;
return newwb;
} else {
abort(); // Should not be possible'
return NULL;
}
}
ADIOS_SELECTION * adios_selection_writeblock (int index)
{
return common_read_selection_writeblock (index);
}
