[Bug tree-optimization/71595] [7 Regression] ICE on valid code at -O2 and -O3 on x86_64-linux-gnu: in check_loop_closed_ssa_use, at tree-ssa-loop-manip.c:704

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=71595

--- Comment #8 from Richard Biener  ---
Author: rguenth
Date: Thu Nov 24 12:25:22 2016
New Revision: 242835

URL: https://gcc.gnu.org/viewcvs?rev=242835=gcc=rev
Log:
2016-11-24  Richard Biener  

PR tree-optimization/71595
* cfgloopmanip.h (remove_path): Add irred_invalidated and
loop_closed_ssa_invalidated parameters, defaulted to NULL.
* cfgloopmanip.c (remove_path): Likewise, pass them along to
called functions.  Only fix irred flags if the caller didn't
request state.
* tree-ssa-loop-ivcanon.c (unloop_loops): Use add_bb_to_loop.
(unloop_loops): Pass irred_invalidated and loop_closed_ssa_invalidated
to remove_path.

* gcc.dg/torture/pr71595.c: New testcase.

Added:
trunk/gcc/testsuite/gcc.dg/torture/pr71595.c
Modified:
trunk/gcc/ChangeLog
trunk/gcc/cfgloopmanip.c
trunk/gcc/cfgloopmanip.h
trunk/gcc/testsuite/ChangeLog
trunk/gcc/tree-ssa-loop-ivcanon.c

[Bug tree-optimization/71595] [7 Regression] ICE on valid code at -O2 and -O3 on x86_64-linux-gnu: in check_loop_closed_ssa_use, at tree-ssa-loop-manip.c:704

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=71595

Richard Biener  changed:

   What|Removed |Added

 Status|ASSIGNED|RESOLVED
 Resolution|--- |FIXED

--- Comment #7 from Richard Biener  ---
Fixed.

[Bug tree-optimization/71595] [7 Regression] ICE on valid code at -O2 and -O3 on x86_64-linux-gnu: in check_loop_closed_ssa_use, at tree-ssa-loop-manip.c:704

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=71595

--- Comment #6 from Richard Biener  ---
diff --git a/gcc/tree-ssa-loop-ivcanon.c b/gcc/tree-ssa-loop-ivcanon.c
index beb65b0..4af39fa 100644
--- a/gcc/tree-ssa-loop-ivcanon.c
+++ b/gcc/tree-ssa-loop-ivcanon.c
@@ -647,7 +647,7 @@ unloop_loops (bitmap loop_closed_ssa_invalidated,
   latch_edge->flags |= flags;
   latch_edge->goto_locus = locus;

-  latch_edge->dest->loop_father = current_loops->tree_root;
+  add_bb_to_loop (latch_edge->dest, current_loops->tree_root);
   latch_edge->dest->count = 0;
   latch_edge->dest->frequency = 0;
   set_immediate_dominator (CDI_DOMINATORS, latch_edge->dest,
latch_edge->src);

fixes that verification issue (but not the loop-closed SSA issue).  It looks
like remove_path doesn't properly update loop_closed_ssa_invalidated.

[Bug tree-optimization/71595] [7 Regression] ICE on valid code at -O2 and -O3 on x86_64-linux-gnu: in check_loop_closed_ssa_use, at tree-ssa-loop-manip.c:704

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=71595

--- Comment #4 from Richard Biener  ---
The real reason is probably that after

  if (changed)
{
  unsigned i;

  unloop_loops (loop_closed_ssa_invalidated, _invalidated);

the loop tree is hosed.  The following into-loop-closed-SSA rewrite cannot
be possibly successful then.

[Bug tree-optimization/71595] [7 Regression] ICE on valid code at -O2 and -O3 on x86_64-linux-gnu: in check_loop_closed_ssa_use, at tree-ssa-loop-manip.c:704

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=71595

Richard Biener  changed:

   What|Removed |Added

 Status|NEW |ASSIGNED
  Known to work||6.2.1
   Assignee|unassigned at gcc dot gnu.org  |rguenth at gcc dot 
gnu.org

--- Comment #5 from Richard Biener  ---
Debug patch:

diff --git a/gcc/tree-ssa-loop-ivcanon.c b/gcc/tree-ssa-loop-ivcanon.c
index beb65b0..6948e62 100644
--- a/gcc/tree-ssa-loop-ivcanon.c
+++ b/gcc/tree-ssa-loop-ivcanon.c
@@ -1379,6 +1379,8 @@ tree_unroll_loops_completely (bool may_increase_size,
bool unroll_outer)

   unloop_loops (loop_closed_ssa_invalidated, _invalidated);

+ verify_loop_structure ();
+
  /* We can not use TODO_update_ssa_no_phi because VOPS gets confused. 
*/
  if (loop_closed_ssa_invalidated
  && !bitmap_empty_p (loop_closed_ssa_invalidated))


mine.

[Bug tree-optimization/71595] [7 Regression] ICE on valid code at -O2 and -O3 on x86_64-linux-gnu: in check_loop_closed_ssa_use, at tree-ssa-loop-manip.c:704

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=71595

Andrew Pinski  changed:

   What|Removed |Added

   Target Milestone|--- |7.0

[Bug tree-optimization/71595] [7 Regression] ICE on valid code at -O2 and -O3 on x86_64-linux-gnu: in check_loop_closed_ssa_use, at tree-ssa-loop-manip.c:704

[msebor at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=71595

Martin Sebor  changed:

   What|Removed |Added

 CC||msebor at gcc dot gnu.org
  Known to fail||7.0

--- Comment #3 from Martin Sebor  ---
The ICE was introduced in r236874:

r236874 | hubicka | 2016-05-30 06:40:33 -0400 (Mon, 30 May 2016) | 10 lines

* predict.h (force_edge_cold): Declare.
* predict.c (force_edge_cold): New function.
* tree-ssa-loop-ivcanon.c (try_unroll_loop_completely): Fix profile
updating.
(canonicalize_loop_induction_variables): Fix formating.

* gcc.dg/tree-ssa/cunroll-12.c: New testcase.
* gcc.dg/tree-ssa/cunroll-13.c: New testcase.
* gcc.dg/tree-ssa/cunroll-14.c: New testcase.