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| author | Zdenek Dvorak <dvorakz@suse.cz> | 2004-12-25 23:53:54 +0100 |
|---|---|---|
| committer | Zdenek Dvorak <rakdver@gcc.gnu.org> | 2004-12-25 22:53:54 +0000 |
| commit | eec5fec983fd8738d842a5d916086b29aeb650bf (patch) | |
| tree | dd158a2937b61524aac9d3dd24821202ba8b51d8 | |
| parent | 6b262ee81e0c4a4d4e2c1afc0b9f6fdb980f7365 (diff) | |
| download | gcc-eec5fec983fd8738d842a5d916086b29aeb650bf.zip gcc-eec5fec983fd8738d842a5d916086b29aeb650bf.tar.gz gcc-eec5fec983fd8738d842a5d916086b29aeb650bf.tar.bz2 | |
re PR rtl-optimization/19078 (Poor quality code after loop unrolling.)
PR rtl-optimization/19078
* tree-ssa-loop-ivopts.c (determine_use_iv_cost_generic,
determine_use_iv_cost_outer): Fix computing of cost for the original
bivs.
(dump_use): Handle case related_cands == NULL.
From-SVN: r92608
| -rw-r--r-- | gcc/ChangeLog | 8 | ||||
| -rw-r--r-- | gcc/tree-ssa-loop-ivopts.c | 34 |
2 files changed, 38 insertions, 4 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 76b79a4..db26b3a 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,11 @@ +2004-12-25 Zdenek Dvorak <dvorakz@suse.cz> + + PR rtl-optimization/19078 + * tree-ssa-loop-ivopts.c (determine_use_iv_cost_generic, + determine_use_iv_cost_outer): Fix computing of cost for the original + bivs. + (dump_use): Handle case related_cands == NULL. + 2004-12-25 Marek Michalkiewicz <marekm@amelek.gda.pl> PR target/19059 diff --git a/gcc/tree-ssa-loop-ivopts.c b/gcc/tree-ssa-loop-ivopts.c index d1a1bdd..7303412 100644 --- a/gcc/tree-ssa-loop-ivopts.c +++ b/gcc/tree-ssa-loop-ivopts.c @@ -444,8 +444,11 @@ dump_use (FILE *file, struct iv_use *use) dump_iv (file, use->iv); - fprintf (file, " related candidates "); - dump_bitmap (file, use->related_cands); + if (use->related_cands) + { + fprintf (file, " related candidates "); + dump_bitmap (file, use->related_cands); + } } /* Dumps information about the uses to FILE. */ @@ -3116,8 +3119,20 @@ determine_use_iv_cost_generic (struct ivopts_data *data, struct iv_use *use, struct iv_cand *cand) { bitmap depends_on; - unsigned cost = get_computation_cost (data, use, cand, false, &depends_on); + unsigned cost; + + /* The simple case first -- if we need to express value of the preserved + original biv, the cost is 0. This also prevents us from counting the + cost of increment twice -- once at this use and once in the cost of + the candidate. */ + if (cand->pos == IP_ORIGINAL + && cand->incremented_at == use->stmt) + { + set_use_iv_cost (data, use, cand, 0, NULL); + return true; + } + cost = get_computation_cost (data, use, cand, false, &depends_on); set_use_iv_cost (data, use, cand, cost, depends_on); return cost != INFTY; @@ -3311,7 +3326,18 @@ determine_use_iv_cost_outer (struct ivopts_data *data, edge exit; tree value; struct loop *loop = data->current_loop; - + + /* The simple case first -- if we need to express value of the preserved + original biv, the cost is 0. This also prevents us from counting the + cost of increment twice -- once at this use and once in the cost of + the candidate. */ + if (cand->pos == IP_ORIGINAL + && cand->incremented_at == use->stmt) + { + set_use_iv_cost (data, use, cand, 0, NULL); + return true; + } + if (!cand->iv) { if (!may_replace_final_value (loop, use, &value)) |