tree-ssa-threadupdate.c (freqs_to_counts_path): Scale frequencies up when synthesizing counts to avoid rounding errors.

2014-10-02  Teresa Johnson  <tejohnson@google.com>

	* tree-ssa-threadupdate.c (freqs_to_counts_path): Scale frequencies
	up when synthesizing counts to avoid rounding errors.

From-SVN: r215830
This commit is contained in:
Teresa Johnson 2014-10-03 00:46:16 +00:00 committed by Teresa Johnson
parent a3f5573622
commit 5d20321177
2 changed files with 18 additions and 3 deletions

View File

@ -1,3 +1,8 @@
2014-10-02 Teresa Johnson <tejohnson@google.com>
* tree-ssa-threadupdate.c (freqs_to_counts_path): Scale frequencies
up when synthesizing counts to avoid rounding errors.
2014-10-02 Teresa Johnson <tejohnson@google.com>
PR middle-end/63422

View File

@ -977,15 +977,25 @@ freqs_to_counts_path (struct redirection_data *rd)
edge ein;
edge_iterator ei;
FOR_EACH_EDGE (ein, ei, e->dest->preds)
ein->count = EDGE_FREQUENCY (ein);
{
/* Scale up the frequency by REG_BR_PROB_BASE, to avoid rounding
errors applying the probability when the frequencies are very
small. */
ein->count = apply_probability (ein->src->frequency * REG_BR_PROB_BASE,
ein->probability);
}
for (unsigned int i = 1; i < path->length (); i++)
{
edge epath = (*path)[i]->e;
edge esucc;
/* Scale up the frequency by REG_BR_PROB_BASE, to avoid rounding
errors applying the edge probability when the frequencies are very
small. */
epath->src->count = epath->src->frequency * REG_BR_PROB_BASE;
FOR_EACH_EDGE (esucc, ei, epath->src->succs)
esucc->count = EDGE_FREQUENCY (esucc);
epath->src->count = epath->src->frequency;
esucc->count = apply_probability (esucc->src->count,
esucc->probability);
}
}