[Bug tree-optimization/66652] try_transform_to_exit_first_loop_alt generates incorrect loop

["vries at gcc dot gnu.org" <gcc-bugzilla at gcc dot gnu dot org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66652

--- Comment #7 from vries at gcc dot gnu.org ---
Author: vries
Date: Tue Jun 30 09:57:20 2015
New Revision: 225166

URL: https://gcc.gnu.org/viewcvs?rev=225166&root=gcc&view=rev
Log:
Backport transform_to_exit_first_loop_alt-related patches

2015-06-30  Tom de Vries  <tom@codesourcery.com>

        backport from trunk:
        2015-06-30  Tom de Vries  <tom@codesourcery.com>

        PR tree-optimization/66652
        * tree-parloops.c (try_transform_to_exit_first_loop_alt): Use
        max_loop_iterations to determine if nit + 1 overflows.

        * testsuite/libgomp.c/parloops-exit-first-loop-alt-3.c (f): Rewrite
        using restrict pointers.
        (main): Add arguments to calls to f.
        * testsuite/libgomp.c/parloops-exit-first-loop-alt.c: Same.

        * gcc.dg/parloops-exit-first-loop-alt-pr66652.c: New test.
        * gcc.dg/parloops-exit-first-loop-alt-3.c (f):  Rewrite using restrict
        pointers.
        * gcc.dg/parloops-exit-first-loop-alt.c: Same.

        2015-06-29  Tom de Vries  <tom@codesourcery.com>

        * tree-parloops.c (try_transform_to_exit_first_loop_alt): Simplify
        function structure.

        2015-06-23  Tom de Vries  <tom@codesourcery.com>

        * testsuite/libgomp.c/parloops-exit-first-loop-alt-3.c (main): Use
        abort.
        * testsuite/libgomp.c/parloops-exit-first-loop-alt-4.c (main): Same.

        2015-06-22  Tom de Vries  <tom@codesourcery.com>

        * tree-parloops.c (transform_to_exit_first_loop_alt): Add update_stmt
        for cond_stmt.

        2015-06-13  Tom de Vries  <tom@codesourcery.com>

        * gcc.dg/parloops-exit-first-loop-alt-4.c: New test.

        * testsuite/libgomp.c/parloops-exit-first-loop-alt-4.c: New test.

        * testsuite/libgomp.c/parloops-exit-first-loop-alt-2.c: Add comment.
        * testsuite/libgomp.c/parloops-exit-first-loop-alt.c: Same.
        * testsuite/libgomp.c/parloops-exit-first-loop-alt-3.c: Add comment.
        (N): Define.
        (main): Use N instead of hardcoded constants.

        * gcc.dg/parloops-exit-first-loop-alt-2.c: Add comment.
        (main): Remove superfluous attributes.
        * gcc.dg/parloops-exit-first-loop-alt-3.c: Same.
        * gcc.dg/parloops-exit-first-loop-alt.c: Same.

Added:
   
branches/gomp-4_0-branch/gcc/testsuite/gcc.dg/parloops-exit-first-loop-alt-4.c
      - copied, changed from r225165,
branches/gomp-4_0-branch/gcc/testsuite/gcc.dg/parloops-exit-first-loop-alt-3.c
   
branches/gomp-4_0-branch/gcc/testsuite/gcc.dg/parloops-exit-first-loop-alt-pr66652.c
   
branches/gomp-4_0-branch/libgomp/testsuite/libgomp.c/parloops-exit-first-loop-alt-4.c
      - copied, changed from r225165,
branches/gomp-4_0-branch/libgomp/testsuite/libgomp.c/parloops-exit-first-loop-alt-3.c
Modified:
    branches/gomp-4_0-branch/gcc/ChangeLog.gomp
    branches/gomp-4_0-branch/gcc/testsuite/ChangeLog.gomp
   
branches/gomp-4_0-branch/gcc/testsuite/gcc.dg/parloops-exit-first-loop-alt-2.c
   
branches/gomp-4_0-branch/gcc/testsuite/gcc.dg/parloops-exit-first-loop-alt-3.c
   
branches/gomp-4_0-branch/gcc/testsuite/gcc.dg/parloops-exit-first-loop-alt.c
    branches/gomp-4_0-branch/gcc/tree-parloops.c
    branches/gomp-4_0-branch/libgomp/ChangeLog.gomp
   
branches/gomp-4_0-branch/libgomp/testsuite/libgomp.c/parloops-exit-first-loop-alt-2.c
   
branches/gomp-4_0-branch/libgomp/testsuite/libgomp.c/parloops-exit-first-loop-alt-3.c
   
branches/gomp-4_0-branch/libgomp/testsuite/libgomp.c/parloops-exit-first-loop-alt.c