[Bug tree-optimization/65518] gcc consumes all memory with -O3

2015-03-23 Thread rguenth at gcc dot gnu.org 
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=65518

--- Comment #4 from Richard Biener rguenth at gcc dot gnu.org ---
Author: rguenth
Date: Mon Mar 23 14:59:57 2015
New Revision: 221595

URL: https://gcc.gnu.org/viewcvs?rev=221595root=gccview=rev
Log:
2015-03-23  Richard Biener  rguent...@suse.de

PR tree-optimization/65518
* tree-vect-stmts.c (vectorizable_load): Reject single-element
interleaving cases we generate absymal code for.

* gcc.dg/vect/pr65518.c: New testcase.

Added:
trunk/gcc/testsuite/gcc.dg/vect/pr65518.c
Modified:
trunk/gcc/ChangeLog
trunk/gcc/testsuite/ChangeLog
trunk/gcc/tree-vect-stmts.c

[Bug tree-optimization/65518] gcc consumes all memory with -O3

2015-03-23 Thread rguenth at gcc dot gnu.org 
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=65518

Richard Biener rguenth at gcc dot gnu.org changed:

   What|Removed |Added

  Known to work||5.0
  Known to fail|5.0 |4.8.3, 4.9.2

--- Comment #3 from Richard Biener rguenth at gcc dot gnu.org ---
Fixed on trunk sofar.

[Bug tree-optimization/65518] gcc consumes all memory with -O3

2015-03-23 Thread rguenth at gcc dot gnu.org 
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=65518

Richard Biener rguenth at gcc dot gnu.org changed:

   What|Removed |Added

 Status|UNCONFIRMED |ASSIGNED
   Last reconfirmed||2015-03-23
   Assignee|unassigned at gcc dot gnu.org  |rguenth at gcc dot 
gnu.org
 Ever confirmed|0   |1
  Known to fail||5.0

--- Comment #2 from Richard Biener rguenth at gcc dot gnu.org ---
Confirmed.

  else
{
  for (i = 0; i  vec_num; i++)
{

and vec_num is 268435456 (after some time) ...  looks uninitialized to me.

(gdb) p group_size
$21 = 268435456

for some reason we detect a grouped load with a single load and group size
268435456:

t.c:9:3: note: === vect_analyze_data_ref_accesses ===
t.c:9:3: note: Detected single element interleaving _6-g[0] step 2147483648
t.c:9:3: note: Data access with gaps requires scalar epilogue loop

[Bug tree-optimization/65518] gcc consumes all memory with -O3

2015-03-22 Thread ikonomisma at googlemail dot com 
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=65518

ikonomisma at googlemail dot com changed:

   What|Removed |Added

  Component|c   |tree-optimization

--- Comment #1 from ikonomisma at googlemail dot com ---
A comment on
http://stackoverflow.com/questions/29200652/gcc-consumes-all-memory-when-optimizing-o3
suggests -ftree-vectorize triggers the condition