[PATCH 1/3] Extended if-conversion

[Yuri Rumyantsev <ysrumyan at gmail dot com>]

Hi ALL,

I decided to resend all patches related to extended if-conversion.
Here is the first patch which contains minimal changes to current
if-conversion pass. Note that FLAG_FORCE_VECTORIZE is temporarily
set-up to false to not break algorithm.

ChangeLog:

2014-11-12  Yuri Rumyantsev  <ysrumyan@gmail.com>

(flag_force_vectorize): New variable.
(edge_predicate): New function.
(set_edge_predicate): New function.
(add_to_dst_predicate_list): Conditionally invoke add_to_predicate_list
if destination block of edge is not always executed. Set-up predicate
for critical edge.
(if_convertible_phi_p): Accept phi nodes with more than two args
if FLAG_FORCE_VECTORIZE was set-up.
(if_convertible_stmt_p): Fix up pre-function comments.
(all_preds_critical_p): New function.
(if_convertible_bb_p): Use call of all_preds_critical_p
to reject temporarily block if-conversion with incoming critical edges
if FLAG_FORCE_VECTORIZE was not set-up. This restriction will be deleted
after adding support for extended predication.
(predicate_bbs): Skip loop exit block also.Invoke build2_loc
to compute predicate instead of fold_build2_loc.
Add zeroing of edge 'aux' field.
(tree_if_conversion): Temporarily set-up FLAG_FORCE_VECTORIZE to false.
Nullify 'aux' field of edges for blocks with two successors.

Attachment: if-conv.patch1
Description: Binary data