From d44bd40ef006102f4001a54a2ac37fbf3b67f128 Mon Sep 17 00:00:00 2001 From: Jeff Law Date: Wed, 7 Oct 2015 15:56:18 -0600 Subject: [PATCH] Re: [PATCH] Improve DOM's optimization of control statements * tree-ssa-dom.c (optimize_stmt): Don't set LOOPS_NEED_FIXUP here. * tree-ssa-threadupdate.c (remove_ctrl_stmt_and_useless_edges): Do it here instead. Tighten test to avoid setting LOOPS_NEED_FIXUP unnecessarily. @@ -1848,12 +1848,6 @@ optimize_stmt (basic_block bb, gimple_stmt_iterator si, From-SVN: r228585 --- gcc/ChangeLog | 8 ++++++++ gcc/tree-ssa-dom.c | 6 ------ gcc/tree-ssa-threadupdate.c | 11 +++++++++++ 3 files changed, 19 insertions(+), 6 deletions(-) diff --git a/gcc/ChangeLog b/gcc/ChangeLog index e2aad2295fa..86be03e5477 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,11 @@ +2015-10-07 Jeff Law + + * tree-ssa-dom.c (optimize_stmt): Don't set LOOPS_NEED_FIXUP here. + * tree-ssa-threadupdate.c (remove_ctrl_stmt_and_useless_edges): Do it + here instead. Tighten test to avoid setting LOOPS_NEED_FIXUP + unnecessarily. + +@@ -1848,12 +1848,6 @@ optimize_stmt (basic_block bb, gimple_stmt_iterator si, 2015-10-07 Aditya Kumar Sebastian Pop diff --git a/gcc/tree-ssa-dom.c b/gcc/tree-ssa-dom.c index 941087d56de..38cceff2c84 100644 --- a/gcc/tree-ssa-dom.c +++ b/gcc/tree-ssa-dom.c @@ -1848,12 +1848,6 @@ optimize_stmt (basic_block bb, gimple_stmt_iterator si, FOR_EACH_EDGE (e, ei, bb->succs) remove_jump_threads_including (e); - /* If BB is in a loop, then removing an outgoing edge from BB - may cause BB to move outside the loop, changes in the - loop exit edges, etc. So note that loops need fixing. */ - if (bb_loop_depth (bb) > 0) - loops_state_set (LOOPS_NEED_FIXUP); - /* Now clean up the control statement at the end of BB and remove unexecutable edges. */ remove_ctrl_stmt_and_useless_edges (bb, taken_edge->dest); diff --git a/gcc/tree-ssa-threadupdate.c b/gcc/tree-ssa-threadupdate.c index 26b199b2c79..e426c1db9e9 100644 --- a/gcc/tree-ssa-threadupdate.c +++ b/gcc/tree-ssa-threadupdate.c @@ -300,6 +300,17 @@ remove_ctrl_stmt_and_useless_edges (basic_block bb, basic_block dest_bb) else ei_next (&ei); } + + /* If the remaining edge is a loop exit, there must have + a removed edge that was not a loop exit. + + In that case BB and possibly other blocks were previously + in the loop, but are now outside the loop. Thus, we need + to update the loop structures. */ + if (single_succ_p (bb) + && loop_outer (bb->loop_father) + && loop_exit_edge_p (bb->loop_father, single_succ_edge (bb))) + loops_state_set (LOOPS_NEED_FIXUP); } /* Create a duplicate of BB. Record the duplicate block in an array -- 2.30.2