diff options
Diffstat (limited to 'gcc/function.c')
-rw-r--r-- | gcc/function.c | 19 |
1 files changed, 16 insertions, 3 deletions
diff --git a/gcc/function.c b/gcc/function.c index a081b270ec0..506ec030745 100644 --- a/gcc/function.c +++ b/gcc/function.c @@ -5956,9 +5956,22 @@ thread_prologue_and_epilogue_insns (void) FOR_EACH_EDGE (e, ei, tmp_bb->preds) if (single_succ_p (e->src) && !bitmap_bit_p (&bb_on_list, e->src->index) - && can_duplicate_block_p (e->src) - && bitmap_set_bit (&bb_tail, e->src->index)) - VEC_quick_push (basic_block, vec, e->src); + && can_duplicate_block_p (e->src)) + { + edge pe; + edge_iterator pei; + + /* If there is predecessor of e->src which doesn't + need prologue and the edge is complex, + we might not be able to redirect the branch + to a copy of e->src. */ + FOR_EACH_EDGE (pe, pei, e->src->preds) + if ((pe->flags & EDGE_COMPLEX) != 0 + && !bitmap_bit_p (&bb_flags, pe->src->index)) + break; + if (pe == NULL && bitmap_set_bit (&bb_tail, e->src->index)) + VEC_quick_push (basic_block, vec, e->src); + } } /* Now walk backwards from every block that is marked as needing |