Re: [PATCH, 6/16] Add pass_oacc_kernels

[Tom de Vries <Tom_deVries at mentor dot com>]

On 19/11/15 14:50, Tom de Vries wrote:
> On 11/11/15 11:58, Richard Biener wrote:
> > On Mon, 9 Nov 2015, Tom de Vries wrote:
> >
> > > On 09/11/15 16:35, Tom de Vries wrote:
> > > > Hi,
> > > >
> > > > this patch series for stage1 trunk adds support to:
> > > > - parallelize oacc kernels regions using parloops, and
> > > > - map the loops onto the oacc gang dimension.
> > > >
> > > > The patch series contains these patches:
> > > >
> > > >        1    Insert new exit block only when needed in
> > > >           transform_to_exit_first_loop_alt
> > > >        2    Make create_parallel_loop return void
> > > >        3    Ignore reduction clause on kernels directive
> > > >        4    Implement -foffload-alias
> > > >        5    Add in_oacc_kernels_region in struct loop
> > > >        6    Add pass_oacc_kernels
> > > >        7    Add pass_dominator_oacc_kernels
> > > >        8    Add pass_ch_oacc_kernels
> > > >        9    Add pass_parallelize_loops_oacc_kernels
> > > >       10    Add pass_oacc_kernels pass group in passes.def
> > > >       11    Update testcases after adding kernels pass group
> > > >       12    Handle acc loop directive
> > > >       13    Add c-c++-common/goacc/kernels-*.c
> > > >       14    Add gfortran.dg/goacc/kernels-*.f95
> > > >       15    Add libgomp.oacc-c-c++-common/kernels-*.c
> > > >       16    Add libgomp.oacc-fortran/kernels-*.f95
> > > >
> > > > The first 9 patches are more or less independent, but patches 10-16 are
> > > > intended to be committed at the same time.
> > > >
> > > > Bootstrapped and reg-tested on x86_64.
> > > >
> > > > Build and reg-tested with nvidia accelerator, in combination with a
> > > > patch that enables accelerator testing (which is submitted at
> > > > https://gcc.gnu.org/ml/gcc-patches/2015-10/msg01771.html ).
> > > >
> > > > I'll post the individual patches in reply to this message.
> > >
> > > this patchs add a pass group pass_oacc_kernels (which will be added
> > > to the
> > > pass list as a whole in patch 10).
> >
> > Just to understand (while also skimming the HSA patches).
> >
> > You are basically relying on autopar for what the HSA patches call
> > "gridification"?  That is, OMP lowering produces loopy kernels
> > and autopar then will basically strip the outermost loop?
>
> Short answer: no. In more detail...
<SNIP>

Reposting patch, after splitting the pass group into two.

Thanks,
- TOm

Add pass_oacc_kernels

2015-11-09  Tom de Vries  <tom@codesourcery.com>

	* tree-pass.h (make_pass_oacc_kernels, make_pass_oacc_kernels2):
	Declare.
	* tree-ssa-loop.c (gate_oacc_kernels): New static function.
	(pass_data_oacc_kernels, pass_data_oacc_kernels2): New pass_data.
	(class pass_oacc_kernels, class pass_oacc_kernels2): New pass.
	(make_pass_oacc_kernels, make_pass_oacc_kernels2): New function.

---
 gcc/tree-pass.h     |   2 +
 gcc/tree-ssa-loop.c | 110 ++++++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 112 insertions(+)

diff --git a/gcc/tree-pass.h b/gcc/tree-pass.h
index dcd2d5e..9704918 100644
--- a/gcc/tree-pass.h
+++ b/gcc/tree-pass.h
@@ -465,6 +465,8 @@ extern gimple_opt_pass *make_pass_strength_reduction (gcc::context *ctxt);
 extern gimple_opt_pass *make_pass_vtable_verify (gcc::context *ctxt);
 extern gimple_opt_pass *make_pass_ubsan (gcc::context *ctxt);
 extern gimple_opt_pass *make_pass_sanopt (gcc::context *ctxt);
+extern gimple_opt_pass *make_pass_oacc_kernels (gcc::context *ctxt);
+extern gimple_opt_pass *make_pass_oacc_kernels2 (gcc::context *ctxt);
 
 /* IPA Passes */
 extern simple_ipa_opt_pass *make_pass_ipa_lower_emutls (gcc::context *ctxt);
diff --git a/gcc/tree-ssa-loop.c b/gcc/tree-ssa-loop.c
index afdef12..cf7d94e 100644
--- a/gcc/tree-ssa-loop.c
+++ b/gcc/tree-ssa-loop.c
@@ -35,6 +35,7 @@ along with GCC; see the file COPYING3.  If not see
 #include "tree-inline.h"
 #include "tree-scalar-evolution.h"
 #include "tree-vectorizer.h"
+#include "omp-low.h"
 
 
 /* A pass making sure loops are fixed up.  */
@@ -141,6 +142,115 @@ make_pass_tree_loop (gcc::context *ctxt)
   return new pass_tree_loop (ctxt);
 }
 
+/* Gate for oacc kernels pass group.  */
+
+static bool
+gate_oacc_kernels (function *fn)
+{
+  if (flag_tree_parallelize_loops <= 1)
+    return false;
+
+  tree oacc_function_attr = get_oacc_fn_attrib (fn->decl);
+  if (oacc_function_attr == NULL_TREE)
+    return false;
+
+  tree val = TREE_VALUE (oacc_function_attr);
+  while (val != NULL_TREE && TREE_VALUE (val) == NULL_TREE)
+    val = TREE_CHAIN (val);
+
+  if (val != NULL_TREE)
+    return false;
+
+  struct loop *loop;
+  FOR_EACH_LOOP (loop, 0)
+    if (loop->in_oacc_kernels_region)
+      return true;
+
+  return false;
+}
+
+/* The oacc kernels superpass.  */
+
+namespace {
+
+const pass_data pass_data_oacc_kernels =
+{
+  GIMPLE_PASS, /* type */
+  "oacc_kernels", /* name */
+  OPTGROUP_LOOP, /* optinfo_flags */
+  TV_TREE_LOOP, /* tv_id */
+  PROP_cfg, /* properties_required */
+  0, /* properties_provided */
+  0, /* properties_destroyed */
+  0, /* todo_flags_start */
+  0, /* todo_flags_finish */
+};
+
+class pass_oacc_kernels : public gimple_opt_pass
+{
+public:
+  pass_oacc_kernels (gcc::context *ctxt)
+    : gimple_opt_pass (pass_data_oacc_kernels, ctxt)
+  {}
+
+  /* opt_pass methods: */
+  virtual bool gate (function *fn) { return gate_oacc_kernels (fn); }
+
+}; // class pass_oacc_kernels
+
+} // anon namespace
+
+gimple_opt_pass *
+make_pass_oacc_kernels (gcc::context *ctxt)
+{
+  return new pass_oacc_kernels (ctxt);
+}
+
+namespace {
+
+const pass_data pass_data_oacc_kernels2 =
+{
+  GIMPLE_PASS, /* type */
+  "oacc_kernels2", /* name */
+  OPTGROUP_LOOP, /* optinfo_flags */
+  TV_TREE_LOOP, /* tv_id */
+  PROP_cfg, /* properties_required */
+  0, /* properties_provided */
+  0, /* properties_destroyed */
+  0, /* todo_flags_start */
+  0, /* todo_flags_finish */
+};
+
+class pass_oacc_kernels2 : public gimple_opt_pass
+{
+public:
+  pass_oacc_kernels2 (gcc::context *ctxt)
+    : gimple_opt_pass (pass_data_oacc_kernels2, ctxt)
+  {}
+
+  /* opt_pass methods: */
+  virtual bool gate (function *fn) { return gate_oacc_kernels (fn); }
+  virtual unsigned int execute (function *fn)
+    {
+      /* Rather than having a copy of the previous dump, get some use out of
+	 this dump, and try to minimize differences with the following pass
+	 (pass_lim), which will initizalize the loop optimizer with
+	 LOOPS_NORMAL.  */
+      loop_optimizer_init (LOOPS_NORMAL);
+      loop_optimizer_finalize (fn);
+      return 0;
+    }
+
+}; // class pass_oacc_kernels2
+
+} // anon namespace
+
+gimple_opt_pass *
+make_pass_oacc_kernels2 (gcc::context *ctxt)
+{
+  return new pass_oacc_kernels2 (ctxt);
+}
+
 /* The no-loop superpass.  */
 
 namespace {