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[svn-r2510] Took memory allocation out of loop and used some temporary variable instead of

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multi-dereferenced pointer chains.  This buys us another ~20% improvement in
the hyperslab I/O speed. (From ~30 seconds to ~25 seconds on the h5hypers
benchmark)
This commit is contained in:
Quincey Koziol 2000-09-06 10:36:37 -05:00
parent 25ee8b4e8f
commit 24b64938a1
1 changed files with 21 additions and 8 deletions
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29
src/H5Shyper.c
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@ -253,7 +253,11 @@ H5S_hyper_get_regions (size_t *num_regions, uintn rank, uintn dim,
{
H5S_hyper_region_t *ret_value=NULL; /* Pointer to array of regions to return */
H5S_hyper_region_t *reg=NULL; /* Pointer to array of regions */
H5S_hyper_bound_t *lo_bound_dim; /* Pointer to the boundary nodes for a given dimension */
H5S_hyper_node_t *node; /* Region node for a given boundary */
hssize_t *node_start,*node_end; /* Extra pointers to node's start & end arrays */
hssize_t *tmp_pos,*tmp_off; /* Extra pointers into the position and offset arrays */
hssize_t pos_dim,off_dim; /* The position & offset in the dimension passed in */
size_t num_reg=0; /* Number of regions in array */
intn curr_reg=-1; /* The current region we are working with */
intn temp_dim; /* Temporary dim. holder */
@ -276,15 +280,27 @@ H5S_hyper_get_regions (size_t *num_regions, uintn rank, uintn dim,
#endif /* QAK */
/* Iterate over the blocks which fit the position, or all of the blocks, if pos[dim]==-1 */
for(i=0; i<bound_count && (pos[dim]<0 || pos[dim]>=lo_bounds[dim][i].bound+offset[dim]); i++) {
lo_bound_dim=lo_bounds[dim];
pos_dim=pos[dim];
off_dim=offset[dim];
for(i=0; i<bound_count && (pos_dim<0 || pos_dim>=lo_bound_dim->bound+off_dim); i++,lo_bound_dim++) {
#ifdef QAK
printf("%s: check 1.2, i=%d, num_reg=%d, curr_reg=%d\n",FUNC,(int)i,(int)num_reg,(int)curr_reg);
#endif /* QAK */
/* Check if each boundary overlaps in the higher dimensions */
node=lo_bounds[dim][i].node;
node=lo_bound_dim->node;
temp_dim=(dim-1);
while(temp_dim>=0 && pos[temp_dim]>=(node->start[temp_dim]+offset[temp_dim]) && pos[temp_dim]<=(node->end[temp_dim]+offset[temp_dim]))
node_start=node->start+temp_dim;
node_end=node->end+temp_dim;
tmp_pos=pos+temp_dim;
tmp_off=offset+temp_dim;
while(temp_dim>=0 && *tmp_pos>=(*node_start+*tmp_off) && *tmp_pos<=(*node_end+*tmp_off)) {
temp_dim--;
node_start--;
node_end--;
tmp_pos--;
tmp_off--;
}
#ifdef QAK
printf("%s: check 1.3, i=%d, temp_dim=%d\n",FUNC,(int)i,(int)temp_dim);
@ -293,8 +309,8 @@ printf("%s: check 1.3, i=%d, temp_dim=%d\n",FUNC,(int)i,(int)temp_dim);
if(temp_dim<0) {
/* Check if we've allocated the array yet */
if(num_reg==0) {
/* Allocate temporary buffer */
reg=H5FL_ARR_ALLOC(H5S_hyper_region_t,1,0);
/* Allocate temporary buffer, big enough for worst case size */
reg=H5FL_ARR_ALLOC(H5S_hyper_region_t,bound_count,0);
/* Initialize with first region */
reg[num_reg].start=MAX(node->start[dim],pos[dim])+offset[dim];
@ -309,9 +325,6 @@ printf("%s: check 1.3, i=%d, temp_dim=%d\n",FUNC,(int)i,(int)temp_dim);
if(dim<(rank-1) && (node->start[dim]+offset[dim])<=(reg[curr_reg].end+1)) {
reg[curr_reg].end=MAX(node->end[dim],reg[curr_reg].end)+offset[dim];
} else { /* no overlap with previous region, add new region */
/* Enlarge array */
reg=H5FL_ARR_REALLOC(H5S_hyper_region_t,reg,num_reg+1);
/* Initialize with new region */
reg[num_reg].start=node->start[dim]+offset[dim];
reg[num_reg].end=node->end[dim]+offset[dim];