From 6e456f4cf4deee3e2ccd9849286f59b90644c48b Mon Sep 17 00:00:00 2001 From: Jakub Jelinek Date: Mon, 12 Dec 2011 22:00:36 +0100 Subject: re PR rtl-optimization/51495 (ICE: in force_nonfallthru_and_redirect, at cfgrtl.c:1171 with computed goto) PR rtl-optimization/51495 * function.c (thread_prologue_and_epilogue_insns): Don't add to bb_tail basic blocks that have EDGE_COMPLEX predecessor edges from basic blocks not needing prologue. * gcc.c-torture/compile/pr51495.c: New test. From-SVN: r182265 --- gcc/function.c | 19 ++++++++++++++++--- 1 file changed, 16 insertions(+), 3 deletions(-) (limited to 'gcc/function.c') diff --git a/gcc/function.c b/gcc/function.c index a081b27..506ec03 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 -- cgit v1.1