| Message ID | CAAe5K+UGneuko=W_UDb9AZ63TQE7O1Ryk2=hwB7h5qBM1QKdAw@mail.gmail.com |
|---|---|
| State | New |
| Headers | show |
> This patch fixes a profile count insanity introduced by ssa tail > merging. When replacing bb1 with bb2, which has the same successors, > the bb counts were being merged, but the successor edge weights > were not. > > Bootstrapped and tested on x86_64-unknown-linux-gnu. Ok for trunk? > > Thanks, > Teresa > > 2013-10-15 Teresa Johnson <tejohnson@google.com> > > * tree-ssa-tail-merge.c (replace_block_by): Update edge > weights during merging. > > Index: tree-ssa-tail-merge.c > =================================================================== > --- tree-ssa-tail-merge.c (revision 203389) > +++ tree-ssa-tail-merge.c (working copy) > @@ -1462,6 +1462,8 @@ static void > replace_block_by (basic_block bb1, basic_block bb2) > { > edge pred_edge; > + edge e1; > + edge_iterator ei; > unsigned int i; > gimple bb2_phi; > > @@ -1488,6 +1490,15 @@ replace_block_by (basic_block bb1, basic_block bb2 > pred_edge, UNKNOWN_LOCATION); > } > > + /* Merge the outgoing edge counts from bb1 onto bb2. */ > + FOR_EACH_EDGE (e1, ei, bb1->succs) > + { > + edge e2; > + e2 = find_edge (bb2, e1->dest); > + gcc_assert (e2); > + e2->count += e1->count; Don't you need to redistribute the counts via edge probabilities? Honza > + } > + > bb2->frequency += bb1->frequency; > if (bb2->frequency > BB_FREQ_MAX) > bb2->frequency = BB_FREQ_MAX; > > > -- > Teresa Johnson | Software Engineer | tejohnson@google.com | 408-460-2413
Index: tree-ssa-tail-merge.c =================================================================== --- tree-ssa-tail-merge.c (revision 203389) +++ tree-ssa-tail-merge.c (working copy) @@ -1462,6 +1462,8 @@ static void replace_block_by (basic_block bb1, basic_block bb2) { edge pred_edge; + edge e1; + edge_iterator ei; unsigned int i; gimple bb2_phi; @@ -1488,6 +1490,15 @@ replace_block_by (basic_block bb1, basic_block bb2 pred_edge, UNKNOWN_LOCATION); } + /* Merge the outgoing edge counts from bb1 onto bb2. */ + FOR_EACH_EDGE (e1, ei, bb1->succs) + { + edge e2; + e2 = find_edge (bb2, e1->dest); + gcc_assert (e2); + e2->count += e1->count; + } + bb2->frequency += bb1->frequency; if (bb2->frequency > BB_FREQ_MAX) bb2->frequency = BB_FREQ_MAX;
This patch fixes a profile count insanity introduced by ssa tail merging. When replacing bb1 with bb2, which has the same successors, the bb counts were being merged, but the successor edge weights were not. Bootstrapped and tested on x86_64-unknown-linux-gnu. Ok for trunk? Thanks, Teresa 2013-10-15 Teresa Johnson <tejohnson@google.com> * tree-ssa-tail-merge.c (replace_block_by): Update edge weights during merging.