/* Delete NODE from HEAP. */
void *
fibheap_delete_node (fibheap_t heap, fibnode_t node)
{
void *ret = node->data;
/* To perform delete, we just make it the min key, and extract. */
fibheap_replace_key (heap, node, FIBHEAPKEY_MIN);
fibheap_extract_min (heap);
return ret;
}
fibnode_t
dirfibheap_insert_or_dec_key( dirfibheap_t self, Vertex* vtx, fibheapkey_t priority )
{
char* key = vtx->label;
fibnode_t fibnode = hashtable_search( self->dir, key );
if( fibnode ) {
fibheap_replace_key( self->heap, fibnode, priority );
} else {
fibnode = fibheap_insert( self->heap, priority, (void*)vtx );
hashtable_insert_string(self->dir, key, fibnode);
}
return fibnode;
}
static void
find_traces_1_round (int branch_th, int exec_th, gcov_type count_th,
struct trace *traces, int *n_traces, int round,
fibheap_t *heap)
{
/* Heap for discarded basic blocks which are possible starting points for
the next round. */
fibheap_t new_heap = fibheap_new ();
while (!fibheap_empty (*heap))
{
basic_block bb;
struct trace *trace;
edge best_edge, e;
fibheapkey_t key;
bb = fibheap_extract_min (*heap);
bbd[bb->index].heap = NULL;
bbd[bb->index].node = NULL;
if (rtl_dump_file)
fprintf (rtl_dump_file, "Getting bb %d\n", bb->index);
/* If the BB's frequency is too low send BB to the next round. */
if (round < N_ROUNDS - 1
&& (bb->frequency < exec_th || bb->count < count_th
|| probably_never_executed_bb_p (bb)))
{
int key = bb_to_key (bb);
bbd[bb->index].heap = new_heap;
bbd[bb->index].node = fibheap_insert (new_heap, key, bb);
if (rtl_dump_file)
fprintf (rtl_dump_file,
" Possible start point of next round: %d (key: %d)\n",
bb->index, key);
continue;
}
trace = traces + *n_traces;
trace->first = bb;
trace->round = round;
trace->length = 0;
(*n_traces)++;
do
{
int prob, freq;
/* The probability and frequency of the best edge. */
int best_prob = INT_MIN / 2;
int best_freq = INT_MIN / 2;
best_edge = NULL;
mark_bb_visited (bb, *n_traces);
trace->length++;
if (rtl_dump_file)
fprintf (rtl_dump_file, "Basic block %d was visited in trace %d\n",
bb->index, *n_traces - 1);
/* Select the successor that will be placed after BB. */
for (e = bb->succ; e; e = e->succ_next)
{
#ifdef ENABLE_CHECKING
if (e->flags & EDGE_FAKE)
abort ();
#endif
if (e->dest == EXIT_BLOCK_PTR)
continue;
if (e->dest->rbi->visited
&& e->dest->rbi->visited != *n_traces)
continue;
prob = e->probability;
freq = EDGE_FREQUENCY (e);
/* Edge that cannot be fallthru or improbable or infrequent
successor (ie. it is unsuitable successor). */
if (!(e->flags & EDGE_CAN_FALLTHRU) || (e->flags & EDGE_COMPLEX)
|| prob < branch_th || freq < exec_th || e->count < count_th)
continue;
if (better_edge_p (bb, e, prob, freq, best_prob, best_freq))
{
best_edge = e;
best_prob = prob;
best_freq = freq;
}
}
/* If the best destination has multiple predecessors, and can be
duplicated cheaper than a jump, don't allow it to be added
to a trace. We'll duplicate it when connecting traces. */
if (best_edge && best_edge->dest->pred->pred_next
&& copy_bb_p (best_edge->dest, 0))
best_edge = NULL;
/* Add all non-selected successors to the heaps. */
for (e = bb->succ; e; e = e->succ_next)
{
if (e == best_edge
|| e->dest == EXIT_BLOCK_PTR
|| e->dest->rbi->visited)
continue;
key = bb_to_key (e->dest);
if (bbd[e->dest->index].heap)
{
/* E->DEST is already in some heap. */
if (key != bbd[e->dest->index].node->key)
{
if (rtl_dump_file)
{
fprintf (rtl_dump_file,
"Changing key for bb %d from %ld to %ld.\n",
e->dest->index,
(long) bbd[e->dest->index].node->key,
key);
}
fibheap_replace_key (bbd[e->dest->index].heap,
bbd[e->dest->index].node, key);
}
}
else
{
fibheap_t which_heap = *heap;
prob = e->probability;
freq = EDGE_FREQUENCY (e);
if (!(e->flags & EDGE_CAN_FALLTHRU)
|| (e->flags & EDGE_COMPLEX)
|| prob < branch_th || freq < exec_th
|| e->count < count_th)
{
if (round < N_ROUNDS - 1)
which_heap = new_heap;
}
bbd[e->dest->index].heap = which_heap;
bbd[e->dest->index].node = fibheap_insert (which_heap,
key, e->dest);
if (rtl_dump_file)
{
fprintf (rtl_dump_file,
" Possible start of %s round: %d (key: %ld)\n",
(which_heap == new_heap) ? "next" : "this",
e->dest->index, (long) key);
}
}
}
if (best_edge) /* Suitable successor was found. */
{
if (best_edge->dest->rbi->visited == *n_traces)
{
/* We do nothing with one basic block loops. */
if (best_edge->dest != bb)
{
if (EDGE_FREQUENCY (best_edge)
> 4 * best_edge->dest->frequency / 5)
{
/* The loop has at least 4 iterations. If the loop
header is not the first block of the function
we can rotate the loop. */
if (best_edge->dest != ENTRY_BLOCK_PTR->next_bb)
{
if (rtl_dump_file)
{
fprintf (rtl_dump_file,
"Rotating loop %d - %d\n",
best_edge->dest->index, bb->index);
}
bb->rbi->next = best_edge->dest;
bb = rotate_loop (best_edge, trace, *n_traces);
}
}
else
{
/* The loop has less than 4 iterations. */
/* Check whether there is another edge from BB. */
edge another_edge;
for (another_edge = bb->succ;
another_edge;
another_edge = another_edge->succ_next)
if (another_edge != best_edge)
break;
if (!another_edge && copy_bb_p (best_edge->dest,
!optimize_size))
{
bb = copy_bb (best_edge->dest, best_edge, bb,
*n_traces);
}
}
}
/* Terminate the trace. */
break;
}
else
{
/* Check for a situation
A
/|
B |
\|
C
where
EDGE_FREQUENCY (AB) + EDGE_FREQUENCY (BC)
>= EDGE_FREQUENCY (AC).
(i.e. 2 * B->frequency >= EDGE_FREQUENCY (AC) )
Best ordering is then A B C.
This situation is created for example by:
if (A) B;
C;
*/
for (e = bb->succ; e; e = e->succ_next)
if (e != best_edge
&& (e->flags & EDGE_CAN_FALLTHRU)
&& !(e->flags & EDGE_COMPLEX)
&& !e->dest->rbi->visited
&& !e->dest->pred->pred_next
&& e->dest->succ
&& (e->dest->succ->flags & EDGE_CAN_FALLTHRU)
&& !(e->dest->succ->flags & EDGE_COMPLEX)
&& !e->dest->succ->succ_next
&& e->dest->succ->dest == best_edge->dest
&& 2 * e->dest->frequency >= EDGE_FREQUENCY (best_edge))
{
best_edge = e;
if (rtl_dump_file)
fprintf (rtl_dump_file, "Selecting BB %d\n",
best_edge->dest->index);
break;
}
bb->rbi->next = best_edge->dest;
bb = best_edge->dest;
}
}
}
while (best_edge);
trace->last = bb;
bbd[trace->first->index].start_of_trace = *n_traces - 1;
bbd[trace->last->index].end_of_trace = *n_traces - 1;
/* The trace is terminated so we have to recount the keys in heap
(some block can have a lower key because now one of its predecessors
is an end of the trace). */
for (e = bb->succ; e; e = e->succ_next)
{
if (e->dest == EXIT_BLOCK_PTR
|| e->dest->rbi->visited)
continue;
if (bbd[e->dest->index].heap)
{
key = bb_to_key (e->dest);
if (key != bbd[e->dest->index].node->key)
{
if (rtl_dump_file)
{
fprintf (rtl_dump_file,
"Changing key for bb %d from %ld to %ld.\n",
e->dest->index,
(long) bbd[e->dest->index].node->key, key);
}
fibheap_replace_key (bbd[e->dest->index].heap,
bbd[e->dest->index].node,
key);
}
}
}
}
fibheap_delete (*heap);
/* "Return" the new heap. */
*heap = new_heap;
}
