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predict.c (block_info_def): Add nvisited.

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* predict.c (block_info_def): Add nvisited.
	(propagate_freq): Count nvisited; re-queue delayed blocks; handle
	irreducible regions.

	* flow.c (dump_edge_info): Dump the probability of edge.
	(combine_predictions_for_insn): Dump the basic block.

From-SVN: r43522
This commit is contained in:
Jan Hubicka 2001-06-23 01:19:22 +02:00 committed by Jan Hubicka
parent c6922dda98
commit 44f498639c
3 changed files with 49 additions and 2 deletions
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9
gcc/ChangeLog
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@ -1,3 +1,12 @@
Sat Jun 23 01:16:42 CEST 2001 Jan Hubicka <jh@suse.cz>
* predict.c (block_info_def): Add nvisited.
(propagate_freq): Count nvisited; re-queue delayed blocks; handle
irreducible regions.
* flow.c (dump_edge_info): Dump the probability of edge.
(combine_predictions_for_insn): Dump the basic block.
2001-06-22 Joseph S. Myers <jsm28@cam.ac.uk>
* doc/gcc.texi: Update documentation of source files of C

3
gcc/flow.c
View File

@ -6405,6 +6405,9 @@ dump_edge_info (file, e, do_succ)
else
fprintf (file, " %d", side->index);
if (e->probability)
fprintf (file, " [%.1f%%] ", e->probability * 100.0 / REG_BR_PROB_BASE);
if (e->count)
{
fprintf (file, " count:");

39
gcc/predict.c
View File

@ -215,7 +215,8 @@ combine_predictions_for_insn (insn, bb)
int best_predictor = END_PREDICTORS;
if (rtl_dump_file)
fprintf (rtl_dump_file, "Predictions for insn %i\n", INSN_UID (insn));
fprintf (rtl_dump_file, "Predictions for insn %i bb %i\n", INSN_UID (insn),
bb->index);
/* We implement "first match" heuristics and use probability guessed
by predictor with smallest index. In future we will use better
@ -541,6 +542,10 @@ typedef struct block_info_def
/* True if block already converted. */
int visited:1;
/* Number of block proceeded before adding basic block to the queue. Used
to recognize irregular regions. */
int nvisited;
} *block_info;
/* Similar information for edges. */
@ -567,6 +572,7 @@ propagate_freq (head)
basic_block last = bb;
edge e;
basic_block nextbb;
int nvisited = 0;
BLOCK_INFO (head)->frequency = 1;
for (; bb; bb = nextbb)
@ -581,12 +587,39 @@ propagate_freq (head)
{
for (e = bb->pred; e; e = e->pred_next)
if (!BLOCK_INFO (e->src)->visited && !EDGE_INFO (e)->back_edge)
break;
/* We didn't proceeded all predecesors of edge e yet. These may
be waiting in the queue or we may hit irreducible region.
To avoid infinite looping on irrecudible regions, count number
of block proceeded at the time basic block has been queued. In the
case number didn't changed, we've hit irreducible region and we
forget the backward edge. This can increase time complexity
by the number of irreducible blocks, but in same way standard the
loop does, so it should not result in noticeable slowodwn.
Alternativly we may distinquish backward and cross edges in the
DFS tree by preprocesing pass and ignore existence of non-loop
backward edges. */
if (e && BLOCK_INFO (bb)->nvisited != nvisited)
{
if (!nextbb)
nextbb = e->dest;
else
BLOCK_INFO (last)->next = e->dest;
BLOCK_INFO (last)->nvisited = nvisited;
last = e->dest;
continue;
}
else if (e && rtl_dump_file)
fprintf (rtl_dump_file, "Irreducible region hit, ignoring edge to bb %i\n",
bb->index);
for (e = bb->pred; e; e = e->pred_next)
if (EDGE_INFO (e)->back_edge)
cyclic_probability += EDGE_INFO (e)->back_edge_prob;
else
else if (BLOCK_INFO (e->src)->visited)
frequency += (e->probability
* BLOCK_INFO (e->src)->frequency /
REG_BR_PROB_BASE);
@ -616,8 +649,10 @@ propagate_freq (head)
nextbb = e->dest;
else
BLOCK_INFO (last)->next = e->dest;
BLOCK_INFO (last)->nvisited = nvisited;
last = e->dest;
}
nvisited ++;
}
}