Re: [gomp4][PATCH] Handle casts in bound in try_transform_to_exit_first_loop_alt
On 22/06/15 16:36, Richard Biener wrote: On Thu, 18 Jun 2015, Tom de Vries wrote: On 13/06/15 16:24, Tom de Vries wrote: Hi, this patch allows try_transform_to_exit_first_loop_alt to succeed when handling cases where the expression representing the number of iterations contains a cast. Currently, transform_to_exit_first_loop_alt testcase gfortran/parloops-exit-first-loop-alt.f95 will fail. The nit is _19, which is defined as follows: ... _20 = _6 + -1; _19 = (unsigned int) _20; ... And transform_to_exit_first_loop_alt currently only handles nits with defining stmt 'nit = x - 1', for which it finds alt_bound 'x'. The patch: - uses try_get_loop_niter to get nit as a nested tree expression '(unsigned int) (_6 + -1)' - strips the outer nops (assuming no change in value) - uses '(unsigned int)_6' as the alt_bound, and - gimplifies the expression. Bootstrapped and reg-tested on x86_64. Cleaned up whitespace in testcases. Committed to gomp-4_0-branch as atttached. OK for trunk? I assume the above also handles the reverse, (int) (_6 + -1)? AFAIU, niter.niter is always unsigned. In this case what happens if _6 == INT_MAX + 1? nit is INT_MAX but (int) _6 is INT_MIN. Likewise what happens if _6 + -1 under-/overflows? While playing around with underflow/overflow cases, I ran into PR66652, which reproduces on trunk. I've submitted for trunk: - https://gcc.gnu.org/ml/gcc-patches/2015-06/msg02084.html , which fixes PR66652, and should handle all overflow concerns. - https://gcc.gnu.org/ml/gcc-patches/2015-06/msg02085.html , which deals with the case that nit is not defined by assignment nit = n - 1, in other words, with the case that this patch is trying to address. I'll revert this patch on gomp-4_0-branch, and commit these patches instead (in addition to https://gcc.gnu.org/ml/gcc-patches/2015-06/msg01768.html, which fixes low iteration count reduction loops handled by transform_to_exit_first_loop_alt). Thanks, - Tom
Re: [gomp4][PATCH] Handle casts in bound in try_transform_to_exit_first_loop_alt
On Thu, 18 Jun 2015, Tom de Vries wrote: On 13/06/15 16:24, Tom de Vries wrote: Hi, this patch allows try_transform_to_exit_first_loop_alt to succeed when handling cases where the expression representing the number of iterations contains a cast. Currently, transform_to_exit_first_loop_alt testcase gfortran/parloops-exit-first-loop-alt.f95 will fail. The nit is _19, which is defined as follows: ... _20 = _6 + -1; _19 = (unsigned int) _20; ... And transform_to_exit_first_loop_alt currently only handles nits with defining stmt 'nit = x - 1', for which it finds alt_bound 'x'. The patch: - uses try_get_loop_niter to get nit as a nested tree expression '(unsigned int) (_6 + -1)' - strips the outer nops (assuming no change in value) - uses '(unsigned int)_6' as the alt_bound, and - gimplifies the expression. Bootstrapped and reg-tested on x86_64. Cleaned up whitespace in testcases. Committed to gomp-4_0-branch as atttached. OK for trunk? I assume the above also handles the reverse, (int) (_6 + -1)? In this case what happens if _6 == INT_MAX + 1? nit is INT_MAX but (int) _6 is INT_MIN. Likewise what happens if _6 + -1 under-/overflows? Richard. Thanks, - Tom -- Richard Biener rguent...@suse.de SUSE LINUX GmbH, GF: Felix Imendoerffer, Jane Smithard, Dilip Upmanyu, Graham Norton, HRB 21284 (AG Nuernberg)
[gomp4][PATCH] Handle casts in bound in try_transform_to_exit_first_loop_alt
On 13/06/15 16:24, Tom de Vries wrote:
Hi,
this patch allows try_transform_to_exit_first_loop_alt to succeed when
handling cases where the expression representing the number of
iterations contains a cast.
Currently, transform_to_exit_first_loop_alt testcase
gfortran/parloops-exit-first-loop-alt.f95 will fail.
The nit is _19, which is defined as follows:
...
_20 = _6 + -1;
_19 = (unsigned int) _20;
...
And transform_to_exit_first_loop_alt currently only handles nits with
defining stmt 'nit = x - 1', for which it finds alt_bound 'x'.
The patch:
- uses try_get_loop_niter to get nit as a nested tree expression
'(unsigned int) (_6 + -1)'
- strips the outer nops (assuming no change in value)
- uses '(unsigned int)_6' as the alt_bound, and
- gimplifies the expression.
Bootstrapped and reg-tested on x86_64.
Cleaned up whitespace in testcases.
Committed to gomp-4_0-branch as atttached.
OK for trunk?
Thanks,
- Tom
Handle casts in bound in transform_to_exit_first_loop_alt
2015-06-13 Tom de Vries t...@codesourcery.com
* tree-parloops.c (transform_to_exit_first_loop_alt): Add update_stmt
for cond_stmt.
(try_get_loop_niter): Declare forward.
(try_transform_to_exit_first_loop_alt): Use try_get_loop_niter to get
updated number of iterations. Extract alt_bount, and instantiate it.
* testsuite/libgomp.fortran/parloops-exit-first-loop-alt-2.f95: New test.
* testsuite/libgomp.fortran/parloops-exit-first-loop-alt.f95: New test.
* gfortran.dg/parloops-exit-first-loop-alt-2.f95: New test.
* gfortran.dg/parloops-exit-first-loop-alt.f95: New test.
---
.../gfortran.dg/parloops-exit-first-loop-alt-2.f95 | 24 +
.../gfortran.dg/parloops-exit-first-loop-alt.f95 | 25 +
gcc/tree-parloops.c| 59 +-
.../parloops-exit-first-loop-alt-2.f95 | 40 +++
.../parloops-exit-first-loop-alt.f95 | 41 +++
5 files changed, 164 insertions(+), 25 deletions(-)
create mode 100644 gcc/testsuite/gfortran.dg/parloops-exit-first-loop-alt-2.f95
create mode 100644 gcc/testsuite/gfortran.dg/parloops-exit-first-loop-alt.f95
create mode 100644 libgomp/testsuite/libgomp.fortran/parloops-exit-first-loop-alt-2.f95
create mode 100644 libgomp/testsuite/libgomp.fortran/parloops-exit-first-loop-alt.f95
diff --git a/gcc/testsuite/gfortran.dg/parloops-exit-first-loop-alt-2.f95 b/gcc/testsuite/gfortran.dg/parloops-exit-first-loop-alt-2.f95
new file mode 100644
index 000..f26a6e3
--- /dev/null
+++ b/gcc/testsuite/gfortran.dg/parloops-exit-first-loop-alt-2.f95
@@ -0,0 +1,24 @@
+! { dg-additional-options -O2 }
+! { dg-require-effective-target pthread }
+! { dg-additional-options -ftree-parallelize-loops=2 }
+! { dg-additional-options -fdump-tree-parloops }
+
+! Constant bound, vector addition.
+
+subroutine foo ()
+ integer, parameter :: n = 1000
+ integer, dimension (0:n-1) :: a, b, c
+ common a, b, c
+ integer :: ii
+
+ do ii = 0, n - 1
+ c(ii) = a(ii) + b(ii) + 25
+ end do
+end subroutine foo
+
+! Three times plus 25:
+! - once in f._loopfn.0
+! - once in the parallel
+! - once in the low iteration count loop
+! Crucially, none for a peeled off last iteration following the parallel.
+! { dg-final { scan-tree-dump-times (?n) \\+ 25; 3 parloops } }
diff --git a/gcc/testsuite/gfortran.dg/parloops-exit-first-loop-alt.f95 b/gcc/testsuite/gfortran.dg/parloops-exit-first-loop-alt.f95
new file mode 100644
index 000..6dc8a38
--- /dev/null
+++ b/gcc/testsuite/gfortran.dg/parloops-exit-first-loop-alt.f95
@@ -0,0 +1,25 @@
+! { dg-additional-options -O2 }
+! { dg-require-effective-target pthread }
+! { dg-additional-options -ftree-parallelize-loops=2 }
+! { dg-additional-options -fdump-tree-parloops }
+
+! Variable bound, vector addition.
+
+subroutine foo (nr)
+ integer, intent(in) :: nr
+ integer, parameter :: n = 1000
+ integer, dimension (0:n-1) :: a, b, c
+ common a, b, c
+ integer :: ii
+
+ do ii = 0, nr - 1
+ c(ii) = a(ii) + b(ii) + 25
+ end do
+end subroutine foo
+
+! Three times plus 25:
+! - once in f._loopfn.0
+! - once in the parallel
+! - once in the low iteration count loop
+! Crucially, none for a peeled off last iteration following the parallel.
+! { dg-final { scan-tree-dump-times (?n) \\+ 25; 3 parloops } }
diff --git a/gcc/tree-parloops.c b/gcc/tree-parloops.c
index 209cf0c..678e458 100644
--- a/gcc/tree-parloops.c
+++ b/gcc/tree-parloops.c
@@ -1684,6 +1684,7 @@ transform_to_exit_first_loop_alt (struct loop *loop,
/* Set the new loop bound. */
gimple_cond_set_rhs (cond_stmt, bound);
+ update_stmt (cond_stmt);
/* Repair the ssa. */
vecedge_var_map *v = redirect_edge_var_map_vector (post_inc_edge);
@@ -1761,6 +1762,8 @@ transform_to_exit_first_loop_alt (struct loop *loop,
calculate_dominance_info (CDI_DOMINATORS);
}
+static bool try_get_loop_niter (loop_p, struct tree_niter_desc *);
+
/* Tries to moves the exit condition of LOOP to the beginning of its
[PATCH] Handle casts in bound in try_transform_to_exit_first_loop_alt
Hi,
this patch allows try_transform_to_exit_first_loop_alt to succeed when
handling cases where the expression representing the number of
iterations contains a cast.
Currently, transform_to_exit_first_loop_alt testcase
gfortran/parloops-exit-first-loop-alt.f95 will fail.
The nit is _19, which is defined as follows:
...
_20 = _6 + -1;
_19 = (unsigned int) _20;
...
And transform_to_exit_first_loop_alt currently only handles nits with
defining stmt 'nit = x - 1', for which it finds alt_bound 'x'.
The patch:
- uses try_get_loop_niter to get nit as a nested tree expression
'(unsigned int) (_6 + -1)'
- strips the outer nops (assuming no change in value)
- uses '(unsigned int)_6' as the alt_bound, and
- gimplifies the expression.
Bootstrapped and reg-tested on x86_64.
OK for trunk?
Thanks,
- Tom
Handle casts in bound in transform_to_exit_first_loop_alt
2015-06-13 Tom de Vries t...@codesourcery.com
* tree-parloops.c (transform_to_exit_first_loop_alt): Add update_stmt
for cond_stmt.
(try_get_loop_niter): Declare forward.
(try_transform_to_exit_first_loop_alt): Use try_get_loop_niter to get
updated number of iterations. Extract alt_bount, and instantiate it.
* testsuite/libgomp.fortran/parloops-exit-first-loop-alt-2.f95: New test.
* testsuite/libgomp.fortran/parloops-exit-first-loop-alt.f95: New test.
* gfortran.dg/parloops-exit-first-loop-alt-2.f95: New test.
* gfortran.dg/parloops-exit-first-loop-alt.f95: New test.
---
.../gfortran.dg/parloops-exit-first-loop-alt-2.f95 | 24 +
.../gfortran.dg/parloops-exit-first-loop-alt.f95 | 25 +
gcc/tree-parloops.c| 59 +-
.../parloops-exit-first-loop-alt-2.f95 | 40 +++
.../parloops-exit-first-loop-alt.f95 | 41 +++
5 files changed, 164 insertions(+), 25 deletions(-)
create mode 100644 gcc/testsuite/gfortran.dg/parloops-exit-first-loop-alt-2.f95
create mode 100644 gcc/testsuite/gfortran.dg/parloops-exit-first-loop-alt.f95
create mode 100644 libgomp/testsuite/libgomp.fortran/parloops-exit-first-loop-alt-2.f95
create mode 100644 libgomp/testsuite/libgomp.fortran/parloops-exit-first-loop-alt.f95
diff --git a/gcc/testsuite/gfortran.dg/parloops-exit-first-loop-alt-2.f95 b/gcc/testsuite/gfortran.dg/parloops-exit-first-loop-alt-2.f95
new file mode 100644
index 000..a785bf9
--- /dev/null
+++ b/gcc/testsuite/gfortran.dg/parloops-exit-first-loop-alt-2.f95
@@ -0,0 +1,24 @@
+! { dg-additional-options -O2 }
+! { dg-require-effective-target pthread }
+! { dg-additional-options -ftree-parallelize-loops=2 }
+! { dg-additional-options -fdump-tree-parloops }
+
+! Constant bound, vector addition.
+
+subroutine foo()
+ integer, parameter :: n = 1000
+ integer, dimension (0:n-1) :: a, b, c
+ common a, b, c
+ integer:: ii
+
+ do ii = 0, n - 1
+ c(ii) = a(ii) + b(ii) + 25
+ end do
+end subroutine foo
+
+! Three times plus 25:
+! - once in f._loopfn.0
+! - once in the parallel
+! - once in the low iteration count loop
+! Crucially, none for a peeled off last iteration following the parallel.
+! { dg-final { scan-tree-dump-times (?n) \\+ 25; 3 parloops } }
diff --git a/gcc/testsuite/gfortran.dg/parloops-exit-first-loop-alt.f95 b/gcc/testsuite/gfortran.dg/parloops-exit-first-loop-alt.f95
new file mode 100644
index 000..3873ca2a
--- /dev/null
+++ b/gcc/testsuite/gfortran.dg/parloops-exit-first-loop-alt.f95
@@ -0,0 +1,25 @@
+! { dg-additional-options -O2 }
+! { dg-require-effective-target pthread }
+! { dg-additional-options -ftree-parallelize-loops=2 }
+! { dg-additional-options -fdump-tree-parloops }
+
+! Variable bound, vector addition.
+
+subroutine foo(nr)
+ integer, intent(in) :: nr
+ integer, parameter :: n = 1000
+ integer, dimension (0:n-1) :: a, b, c
+ common a, b, c
+ integer:: ii
+
+ do ii = 0, nr - 1
+ c(ii) = a(ii) + b(ii) + 25
+ end do
+end subroutine foo
+
+! Three times plus 25:
+! - once in f._loopfn.0
+! - once in the parallel
+! - once in the low iteration count loop
+! Crucially, none for a peeled off last iteration following the parallel.
+! { dg-final { scan-tree-dump-times (?n) \\+ 25; 3 parloops } }
diff --git a/gcc/tree-parloops.c b/gcc/tree-parloops.c
index 3495ac1..6e10901 100644
--- a/gcc/tree-parloops.c
+++ b/gcc/tree-parloops.c
@@ -1678,6 +1678,7 @@ transform_to_exit_first_loop_alt (struct loop *loop,
/* Set the new loop bound. */
gimple_cond_set_rhs (cond_stmt, bound);
+ update_stmt (cond_stmt);
/* Repair the ssa. */
vecedge_var_map *v = redirect_edge_var_map_vector (post_inc_edge);
@@ -1755,6 +1756,8 @@ transform_to_exit_first_loop_alt (struct loop *loop,
calculate_dominance_info (CDI_DOMINATORS);
}
+static bool try_get_loop_niter (loop_p, struct tree_niter_desc *);
+
/* Tries to moves the exit condition of LOOP to the beginning of its header
without duplication of the loop body. NIT is the
