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Add edge predictions pruning
* analyze_brprob.py: Cover new dump output format. * predict.c (dump_prediction): Add new argument. (enum predictor_reason): New enum. (struct predictor_hash): New struct. (predictor_hash::hash): New function. (predictor_hash::equal): Likewise. (not_removed_prediction_p): New function. (prune_predictions_for_bb): Likewise. (combine_predictions_for_bb): Prune predictions. * g++.dg/predict-loop-exit-1.C: Scan for a new dump format. * g++.dg/predict-loop-exit-2.C: Likewise. * g++.dg/predict-loop-exit-3.C: Likewise. * gcc.dg/predict-1.c: Likewise. * gcc.dg/predict-2.c: Likewise. * gcc.dg/predict-3.c: Likewise. * gcc.dg/predict-4.c: Likewise. * gcc.dg/predict-5.c: Likewise. * gcc.dg/predict-6.c: Likewise. * gcc.dg/predict-7.c: Likewise. From-SVN: r237255
This commit is contained in:
Martin Liska
Martin Liska
parent
36d5798666
commit
e49efc14a1
@ -1,3 +1,7 @@
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2016-06-09 Martin Liska <mliska@suse.cz>
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* analyze_brprob.py: Cover new dump output format.
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2016-06-07 Rainer Orth <ro@CeBiTec.Uni-Bielefeld.DE>
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* update-copyright.py (LibMudflapFilter): Remove.
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@ -122,14 +122,14 @@ if len(sys.argv) != 2:
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exit(1)
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profile = Profile(sys.argv[1])
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r = re.compile(' (.*) heuristics: (.*)%.*exec ([0-9]*) hit ([0-9]*)')
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r = re.compile(' (.*) heuristics( of edge [0-9]*->[0-9]*)?( \\(.*\\))?: (.*)%.*exec ([0-9]*) hit ([0-9]*)')
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for l in open(profile.filename).readlines():
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m = r.match(l)
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if m != None:
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if m != None and m.group(3) == None:
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name = m.group(1)
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prediction = float(m.group(2))
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count = int(m.group(3))
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hits = int(m.group(4))
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prediction = float(m.group(4))
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count = int(m.group(5))
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hits = int(m.group(6))
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profile.add(name, prediction, count, hits)
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@ -4,6 +4,17 @@
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* tree-ssa-loop-manip.c (find_uses_to_rename): Guard against
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removed blocks.
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2016-06-09 Martin Liska <mliska@suse.cz>
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* predict.c (dump_prediction): Add new argument.
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(enum predictor_reason): New enum.
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(struct predictor_hash): New struct.
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(predictor_hash::hash): New function.
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(predictor_hash::equal): Likewise.
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(not_removed_prediction_p): New function.
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(prune_predictions_for_bb): Likewise.
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(combine_predictions_for_bb): Prune predictions.
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2016-06-09 Martin Liska <mliska@suse.cz>
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* predict.c (filter_predictions): New function.
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184
gcc/predict.c
184
gcc/predict.c
@ -55,13 +55,29 @@ along with GCC; see the file COPYING3. If not see
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#include "tree-ssa-loop.h"
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#include "tree-scalar-evolution.h"
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/* Enum with reasons why a predictor is ignored. */
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enum predictor_reason
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{
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NONE,
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IGNORED,
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SINGLE_EDGE_DUPLICATE,
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EDGE_PAIR_DUPLICATE
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};
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/* String messages for the aforementioned enum. */
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static const char *reason_messages[] = {"", " (ignored)",
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" (single edge duplicate)", " (edge pair duplicate)"};
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/* real constants: 0, 1, 1-1/REG_BR_PROB_BASE, REG_BR_PROB_BASE,
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1/REG_BR_PROB_BASE, 0.5, BB_FREQ_MAX. */
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static sreal real_almost_one, real_br_prob_base,
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real_inv_br_prob_base, real_one_half, real_bb_freq_max;
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static void combine_predictions_for_insn (rtx_insn *, basic_block);
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static void dump_prediction (FILE *, enum br_predictor, int, basic_block, int);
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static void dump_prediction (FILE *, enum br_predictor, int, basic_block,
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enum predictor_reason, edge);
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static void predict_paths_leading_to (basic_block, enum br_predictor, enum prediction);
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static void predict_paths_leading_to_edge (edge, enum br_predictor, enum prediction);
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static bool can_predict_insn_p (const rtx_insn *);
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@ -723,21 +739,31 @@ invert_br_probabilities (rtx insn)
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static void
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dump_prediction (FILE *file, enum br_predictor predictor, int probability,
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basic_block bb, int used)
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basic_block bb, enum predictor_reason reason = NONE,
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edge ep_edge = NULL)
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{
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edge e;
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edge e = ep_edge;
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edge_iterator ei;
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if (!file)
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return;
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FOR_EACH_EDGE (e, ei, bb->succs)
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if (! (e->flags & EDGE_FALLTHRU))
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break;
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if (e == NULL)
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FOR_EACH_EDGE (e, ei, bb->succs)
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if (! (e->flags & EDGE_FALLTHRU))
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break;
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fprintf (file, " %s heuristics%s: %.1f%%",
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char edge_info_str[128];
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if (ep_edge)
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sprintf (edge_info_str, " of edge %d->%d", ep_edge->src->index,
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ep_edge->dest->index);
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else
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edge_info_str[0] = '\0';
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fprintf (file, " %s heuristics%s%s: %.1f%%",
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predictor_info[predictor].name,
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used ? "" : " (ignored)", probability * 100.0 / REG_BR_PROB_BASE);
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edge_info_str, reason_messages[reason],
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probability * 100.0 / REG_BR_PROB_BASE);
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if (bb->count)
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{
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@ -834,18 +860,18 @@ combine_predictions_for_insn (rtx_insn *insn, basic_block bb)
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if (!found)
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dump_prediction (dump_file, PRED_NO_PREDICTION,
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combined_probability, bb, true);
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combined_probability, bb);
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else
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{
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dump_prediction (dump_file, PRED_DS_THEORY, combined_probability,
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bb, !first_match);
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bb, !first_match ? NONE : IGNORED);
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dump_prediction (dump_file, PRED_FIRST_MATCH, best_probability,
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bb, first_match);
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bb, first_match ? NONE: IGNORED);
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}
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if (first_match)
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combined_probability = best_probability;
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dump_prediction (dump_file, PRED_COMBINED, combined_probability, bb, true);
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dump_prediction (dump_file, PRED_COMBINED, combined_probability, bb);
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while (*pnote)
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{
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@ -856,7 +882,8 @@ combine_predictions_for_insn (rtx_insn *insn, basic_block bb)
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int probability = INTVAL (XEXP (XEXP (*pnote, 0), 1));
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dump_prediction (dump_file, predictor, probability, bb,
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!first_match || best_predictor == predictor);
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(!first_match || best_predictor == predictor)
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? NONE : IGNORED);
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*pnote = XEXP (*pnote, 1);
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}
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else
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@ -887,6 +914,121 @@ combine_predictions_for_insn (rtx_insn *insn, basic_block bb)
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single_succ_edge (bb)->probability = REG_BR_PROB_BASE;
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}
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/* Edge prediction hash traits. */
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struct predictor_hash: pointer_hash <edge_prediction>
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{
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static inline hashval_t hash (const edge_prediction *);
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static inline bool equal (const edge_prediction *, const edge_prediction *);
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};
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/* Calculate hash value of an edge prediction P based on predictor and
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normalized probability. */
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inline hashval_t
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predictor_hash::hash (const edge_prediction *p)
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{
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inchash::hash hstate;
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hstate.add_int (p->ep_predictor);
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int prob = p->ep_probability;
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if (prob > REG_BR_PROB_BASE / 2)
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prob = REG_BR_PROB_BASE - prob;
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hstate.add_int (prob);
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return hstate.end ();
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}
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/* Return true whether edge predictions P1 and P2 use the same predictor and
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have equal (or opposed probability). */
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inline bool
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predictor_hash::equal (const edge_prediction *p1, const edge_prediction *p2)
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{
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return (p1->ep_predictor == p2->ep_predictor
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&& (p1->ep_probability == p2->ep_probability
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|| p1->ep_probability == REG_BR_PROB_BASE - p2->ep_probability));
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}
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struct predictor_hash_traits: predictor_hash,
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typed_noop_remove <edge_prediction *> {};
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/* Return true if edge prediction P is not in DATA hash set. */
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static bool
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not_removed_prediction_p (edge_prediction *p, void *data)
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{
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hash_set<edge_prediction *> *remove = (hash_set<edge_prediction *> *) data;
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return !remove->contains (p);
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}
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/* Prune predictions for a basic block BB. Currently we do following
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clean-up steps:
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1) remove duplicate prediction that is guessed with the same probability
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(different than 1/2) to both edge
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2) remove duplicates for a prediction that belongs with the same probability
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to a single edge
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*/
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static void
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prune_predictions_for_bb (basic_block bb)
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{
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edge_prediction **preds = bb_predictions->get (bb);
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if (preds)
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{
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hash_table <predictor_hash_traits> s (13);
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hash_set <edge_prediction *> remove;
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/* Step 1: identify predictors that should be removed. */
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for (edge_prediction *pred = *preds; pred; pred = pred->ep_next)
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{
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edge_prediction *existing = s.find (pred);
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if (existing)
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{
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if (pred->ep_edge == existing->ep_edge
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&& pred->ep_probability == existing->ep_probability)
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{
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/* Remove a duplicate predictor. */
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dump_prediction (dump_file, pred->ep_predictor,
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pred->ep_probability, bb,
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SINGLE_EDGE_DUPLICATE, pred->ep_edge);
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remove.add (pred);
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}
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else if (pred->ep_edge != existing->ep_edge
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&& pred->ep_probability == existing->ep_probability
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&& pred->ep_probability != REG_BR_PROB_BASE / 2)
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{
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/* Remove both predictors as they predict the same
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for both edges. */
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dump_prediction (dump_file, existing->ep_predictor,
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pred->ep_probability, bb,
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EDGE_PAIR_DUPLICATE,
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existing->ep_edge);
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dump_prediction (dump_file, pred->ep_predictor,
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pred->ep_probability, bb,
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EDGE_PAIR_DUPLICATE,
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pred->ep_edge);
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remove.add (existing);
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remove.add (pred);
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}
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}
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edge_prediction **slot2 = s.find_slot (pred, INSERT);
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*slot2 = pred;
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}
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/* Step 2: Remove predictors. */
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filter_predictions (preds, not_removed_prediction_p, &remove);
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}
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}
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/* Combine predictions into single probability and store them into CFG.
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Remove now useless prediction entries.
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If DRY_RUN is set, only produce dumps and do not modify profile. */
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@ -935,7 +1077,10 @@ combine_predictions_for_bb (basic_block bb, bool dry_run)
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if (dump_file)
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fprintf (dump_file, "Predictions for bb %i\n", bb->index);
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prune_predictions_for_bb (bb);
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edge_prediction **preds = bb_predictions->get (bb);
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if (preds)
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{
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/* We implement "first match" heuristics and use probability guessed
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@ -1001,18 +1146,18 @@ combine_predictions_for_bb (basic_block bb, bool dry_run)
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first_match = true;
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if (!found)
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dump_prediction (dump_file, PRED_NO_PREDICTION, combined_probability, bb, true);
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dump_prediction (dump_file, PRED_NO_PREDICTION, combined_probability, bb);
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else
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{
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dump_prediction (dump_file, PRED_DS_THEORY, combined_probability, bb,
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!first_match);
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!first_match ? NONE : IGNORED);
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dump_prediction (dump_file, PRED_FIRST_MATCH, best_probability, bb,
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first_match);
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first_match ? NONE : IGNORED);
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}
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if (first_match)
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combined_probability = best_probability;
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dump_prediction (dump_file, PRED_COMBINED, combined_probability, bb, true);
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dump_prediction (dump_file, PRED_COMBINED, combined_probability, bb);
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if (preds)
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{
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@ -1021,10 +1166,9 @@ combine_predictions_for_bb (basic_block bb, bool dry_run)
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enum br_predictor predictor = pred->ep_predictor;
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int probability = pred->ep_probability;
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if (pred->ep_edge != EDGE_SUCC (bb, 0))
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probability = REG_BR_PROB_BASE - probability;
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dump_prediction (dump_file, predictor, probability, bb,
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!first_match || best_predictor == predictor);
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(!first_match || best_predictor == predictor)
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? NONE : IGNORED, pred->ep_edge);
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}
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}
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clear_bb_predictions (bb);
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@ -1,3 +1,16 @@
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2016-06-09 Martin Liska <mliska@suse.cz>
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* g++.dg/predict-loop-exit-1.C: Scan for a new dump format.
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* g++.dg/predict-loop-exit-2.C: Likewise.
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* g++.dg/predict-loop-exit-3.C: Likewise.
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* gcc.dg/predict-1.c: Likewise.
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* gcc.dg/predict-2.c: Likewise.
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* gcc.dg/predict-3.c: Likewise.
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* gcc.dg/predict-4.c: Likewise.
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* gcc.dg/predict-5.c: Likewise.
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* gcc.dg/predict-6.c: Likewise.
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* gcc.dg/predict-7.c: Likewise.
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2016-06-09 Richard Biener <rguenther@suse.de>
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PR tree-optimization/71462
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@ -9,5 +9,5 @@ void test() {
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return;
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}
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/* { dg-final { scan-tree-dump-times "extra loop exit heuristics:" 2 "profile_estimate"} } */
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/* { dg-final { scan-tree-dump-times "loop exit heuristics:" 3 "profile_estimate"} } */
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/* { dg-final { scan-tree-dump-times "extra loop exit heuristics of edge\[^:\]*:" 2 "profile_estimate"} } */
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/* { dg-final { scan-tree-dump-times "loop exit heuristics of edge\[^:\]*:" 3 "profile_estimate"} } */
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@ -9,5 +9,5 @@ void test() {
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return;
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}
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/* { dg-final { scan-tree-dump-times "extra loop exit heuristics:" 1 "profile_estimate"} } */
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/* { dg-final { scan-tree-dump-times "loop exit heuristics:" 2 "profile_estimate"} } */
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/* { dg-final { scan-tree-dump-times "extra loop exit heuristics of edge\[^:\]*:" 1 "profile_estimate"} } */
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/* { dg-final { scan-tree-dump-times "loop exit heuristics of edge\[^:\]*:" 2 "profile_estimate"} } */
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@ -9,5 +9,5 @@ void test() {
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return;
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}
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/* { dg-final { scan-tree-dump-times "extra loop exit heuristics:" 2 "profile_estimate"} } */
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/* { dg-final { scan-tree-dump-times "loop exit heuristics:" 3 "profile_estimate"} } */
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/* { dg-final { scan-tree-dump-times "extra loop exit heuristics of edge\[^:\]*:" 2 "profile_estimate"} } */
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/* { dg-final { scan-tree-dump-times "loop exit heuristics of edge\[^:\]*:" 3 "profile_estimate"} } */
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@ -23,4 +23,4 @@ void foo (int bound)
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}
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}
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/* { dg-final { scan-tree-dump-times "loop iv compare heuristics: 2.0%" 5 "profile_estimate"} } */
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/* { dg-final { scan-tree-dump-times "loop iv compare heuristics of edge\[^:\]*: 2.0%" 5 "profile_estimate"} } */
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@ -23,4 +23,4 @@ void foo (int base, int bound)
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}
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}
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/* { dg-final { scan-tree-dump-not "loop iv compare heuristics" "profile_estimate"} } */
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/* { dg-final { scan-tree-dump-not "loop iv compare heuristics of edge\[^:\]*:" "profile_estimate"} } */
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@ -25,4 +25,4 @@ void foo (int bound)
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}
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}
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/* { dg-final { scan-tree-dump-times "loop iv compare heuristics: 98.0%" 3 "profile_estimate"} } */
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/* { dg-final { scan-tree-dump-times "loop iv compare heuristics of edge\[^:\]*: 98.0%" 3 "profile_estimate"} } */
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@ -15,4 +15,4 @@ void foo (int bound)
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}
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}
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/* { dg-final { scan-tree-dump "loop iv compare heuristics: 50.0%" "profile_estimate"} } */
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/* { dg-final { scan-tree-dump "loop iv compare heuristics of edge\[^:\]*: 50.0%" "profile_estimate"} } */
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@ -21,4 +21,4 @@ void foo (int base, int bound)
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}
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}
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/* { dg-final { scan-tree-dump-times "loop iv compare heuristics: 98.0%" 4 "profile_estimate"} } */
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/* { dg-final { scan-tree-dump-times "loop iv compare heuristics of edge\[^:\]*: 98.0%" 4 "profile_estimate"} } */
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@ -21,4 +21,4 @@ void foo (int base, int bound)
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}
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}
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/* { dg-final { scan-tree-dump-times "loop iv compare heuristics: 2.0%" 4 "profile_estimate"} } */
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/* { dg-final { scan-tree-dump-times "loop iv compare heuristics of edge\[^:\]*: 2.0%" 4 "profile_estimate"} } */
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@ -13,4 +13,4 @@ void foo (int base)
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bar (i);
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}
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/* { dg-final { scan-tree-dump-times "loop branch heuristics" 0 "profile_estimate"} } */
|
||||
/* { dg-final { scan-tree-dump-times "loop branch heuristics of edge\[^:\]*" 0 "profile_estimate"} } */
|
||||
|
||||
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Reference in New Issue
Block a user