[PATCH] Improve comments in pass_tree_loop_init::execute
Hi, this no-functional-changes patch improves comments in pass_tree_loop_init::execute. For the discussion related to the comment for scev_initialize, see: - https://gcc.gnu.org/ml/gcc-patches/2013-02/msg01127.html - https://gcc.gnu.org/bugzilla/show_bug.cgi?id=56426 OK for trunk? Thanks, - Tom Improve comments in pass_tree_loop_init::execute 2015-11-17 Tom de Vries* tree-ssa-loop.c (pass_tree_loop_init::execute): Improve comments. --- gcc/tree-ssa-loop.c | 13 +++-- 1 file changed, 11 insertions(+), 2 deletions(-) diff --git a/gcc/tree-ssa-loop.c b/gcc/tree-ssa-loop.c index 570406f..40df84f 100644 --- a/gcc/tree-ssa-loop.c +++ b/gcc/tree-ssa-loop.c @@ -276,12 +276,21 @@ public: unsigned int pass_tree_loop_init::execute (function *fun ATTRIBUTE_UNUSED) { + /* When processing a loop in the loop pipeline, we should be able to assert + that: + (loops_state_satisfies_p (LOOPS_NORMAL | LOOPS_HAVE_RECORDED_EXITS + | LOOP_CLOSED_SSA) + && scev_initialized_p ()) + */ + loop_optimizer_init (LOOPS_NORMAL | LOOPS_HAVE_RECORDED_EXITS); rewrite_into_loop_closed_ssa (NULL, TODO_update_ssa); - /* We might discover new loops, e.g. when turning irreducible - regions into reducible. */ + /* Note that we run scev_initialize here even if number_of_loops () <= 1. + Even if we have no real loops now, we might discover new loops while + executing the loop pipeline, e.g. when turning irreducible regions into + reducible, in which case we still would need scev to be initialized. */ scev_initialize (); return 0;
Re: [PATCH] Improve comments in pass_tree_loop_init::execute
On Tue, 17 Nov 2015, Tom de Vries wrote: > Hi, > > this no-functional-changes patch improves comments in > pass_tree_loop_init::execute. > > For the discussion related to the comment for scev_initialize, see: > - https://gcc.gnu.org/ml/gcc-patches/2013-02/msg01127.html > - https://gcc.gnu.org/bugzilla/show_bug.cgi?id=56426 > > OK for trunk? The comment about SCEV is no longer accurate as we gate pass_tree_loop on having "real" loops. Richard. > Thanks, > - Tom > -- Richard BienerSUSE LINUX GmbH, GF: Felix Imendoerffer, Jane Smithard, Graham Norton, HRB 21284 (AG Nuernberg)
Re: [PATCH] Improve comments in pass_tree_loop_init::execute
On 17/11/15 12:41, Richard Biener wrote: On Tue, 17 Nov 2015, Tom de Vries wrote: Hi, this no-functional-changes patch improves comments in pass_tree_loop_init::execute. For the discussion related to the comment for scev_initialize, see: - https://gcc.gnu.org/ml/gcc-patches/2013-02/msg01127.html - https://gcc.gnu.org/bugzilla/show_bug.cgi?id=56426 OK for trunk? The comment about SCEV is no longer accurate as we gate pass_tree_loop on having "real" loops. I see. Removed scev comment, committed as attached. Thanks, - Tom Improve comments in pass_tree_loop_init::execute 2015-11-17 Tom de Vries* tree-ssa-loop.c (pass_tree_loop_init::execute): Improve comments. --- gcc/tree-ssa-loop.c | 9 ++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/gcc/tree-ssa-loop.c b/gcc/tree-ssa-loop.c index 8ecd140..afdef12 100644 --- a/gcc/tree-ssa-loop.c +++ b/gcc/tree-ssa-loop.c @@ -211,12 +211,15 @@ public: unsigned int pass_tree_loop_init::execute (function *fun ATTRIBUTE_UNUSED) { + /* When processing a loop in the loop pipeline, we should be able to assert + that: + (loops_state_satisfies_p (LOOPS_NORMAL | LOOPS_HAVE_RECORDED_EXITS + | LOOP_CLOSED_SSA) + && scev_initialized_p ()) + */ loop_optimizer_init (LOOPS_NORMAL | LOOPS_HAVE_RECORDED_EXITS); rewrite_into_loop_closed_ssa (NULL, TODO_update_ssa); - - /* We might discover new loops, e.g. when turning irreducible - regions into reducible. */ scev_initialize (); return 0;