diff options
Diffstat (limited to 'gcc/tree-inline.c')
| -rw-r--r-- | gcc/tree-inline.c | 41 |
1 files changed, 41 insertions, 0 deletions
diff --git a/gcc/tree-inline.c b/gcc/tree-inline.c index 77013b3..0d1f1c7 100644 --- a/gcc/tree-inline.c +++ b/gcc/tree-inline.c @@ -2353,6 +2353,29 @@ redirect_all_calls (copy_body_data * id, basic_block bb) } } +/* Convert estimated frequencies into counts for NODE, scaling COUNT + with each bb's frequency. Used when NODE has a 0-weight entry + but we are about to inline it into a non-zero count call bb. + See the comments for handle_missing_profiles() in predict.c for + when this can happen for COMDATs. */ + +void +freqs_to_counts (struct cgraph_node *node, gcov_type count) +{ + basic_block bb; + edge_iterator ei; + edge e; + struct function *fn = DECL_STRUCT_FUNCTION (node->decl); + + FOR_ALL_BB_FN(bb, fn) + { + bb->count = apply_scale (count, + GCOV_COMPUTE_SCALE (bb->frequency, BB_FREQ_MAX)); + FOR_EACH_EDGE (e, ei, bb->succs) + e->count = apply_probability (e->src->count, e->probability); + } +} + /* Make a copy of the body of FN so that it can be inserted inline in another function. Walks FN via CFG, returns new fndecl. */ @@ -2373,6 +2396,24 @@ copy_cfg_body (copy_body_data * id, gcov_type count, int frequency_scale, int incoming_frequency = 0; gcov_type incoming_count = 0; + /* This can happen for COMDAT routines that end up with 0 counts + despite being called (see the comments for handle_missing_profiles() + in predict.c as to why). Apply counts to the blocks in the callee + before inlining, using the guessed edge frequencies, so that we don't + end up with a 0-count inline body which can confuse downstream + optimizations such as function splitting. */ + if (!ENTRY_BLOCK_PTR_FOR_FUNCTION (src_cfun)->count && count) + { + /* Apply the larger of the call bb count and the total incoming + call edge count to the callee. */ + gcov_type in_count = 0; + struct cgraph_edge *in_edge; + for (in_edge = id->src_node->callers; in_edge; + in_edge = in_edge->next_caller) + in_count += in_edge->count; + freqs_to_counts (id->src_node, count > in_count ? count : in_count); + } + if (ENTRY_BLOCK_PTR_FOR_FUNCTION (src_cfun)->count) count_scale = GCOV_COMPUTE_SCALE (count, |