Add in_oacc_kernels_region in struct loop

2015-11-17  Tom de Vries  <tom@codesourcery.com>

	* cfgloop.h (struct loop): Add in_oacc_kernels_region field.
	* omp-low.c (mark_loops_in_oacc_kernels_region): New function.
	(expand_omp_target): Call mark_loops_in_oacc_kernels_region.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@230502 138bc75d-0d04-0410-961f-82ee72b054a4

4 files changed, 53 insertions, 0 deletions

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 869685077c8..b208b470c0b 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,9 @@
+2015-11-17  Tom de Vries  <tom@codesourcery.com>
+
+	* cfgloop.h (struct loop): Add in_oacc_kernels_region field.
+	* omp-low.c (mark_loops_in_oacc_kernels_region): New function.
+	(expand_omp_target): Call mark_loops_in_oacc_kernels_region.
+
 2015-11-17  Bernd Schmidt  <bschmidt@redhat.com>
 
 	* regrename.c (regrename_find_superclass): New function, code moved
diff --git a/gcc/cfgloop.h b/gcc/cfgloop.h
index 6af68939eda..ee73bf994c1 100644
--- a/gcc/cfgloop.h
+++ b/gcc/cfgloop.h
@@ -191,6 +191,9 @@ struct GTY ((chain_next ("%h.next"))) loop {
   /* True if we should try harder to vectorize this loop.  */
   bool force_vectorize;
 
+  /* True if the loop is part of an oacc kernels region.  */
+  bool in_oacc_kernels_region;
+
   /* For SIMD loops, this is a unique identifier of the loop, referenced
      by IFN_GOMP_SIMD_VF, IFN_GOMP_SIMD_LANE and IFN_GOMP_SIMD_LAST_LANE
      builtins.  */
diff --git a/gcc/cfgloopmanip.c b/gcc/cfgloopmanip.c
index 97df42f28dd..b327abd490d 100644
--- a/gcc/cfgloopmanip.c
+++ b/gcc/cfgloopmanip.c
@@ -1021,6 +1021,7 @@ copy_loop_info (struct loop *loop, struct loop *target)
   target->estimate_state = loop->estimate_state;
   target->warned_aggressive_loop_optimizations
     |= loop->warned_aggressive_loop_optimizations;
+  target->in_oacc_kernels_region = loop->in_oacc_kernels_region;
 }
 
 /* Copies copy of LOOP as subloop of TARGET loop, placing newly
diff --git a/gcc/omp-low.c b/gcc/omp-low.c
index efcc971b98a..830db75a0e6 100644
--- a/gcc/omp-low.c
+++ b/gcc/omp-low.c
@@ -12426,6 +12426,46 @@ get_oacc_ifn_dim_arg (const gimple *stmt)
   return (int) axis;
 }
 
+/* Mark the loops inside the kernels region starting at REGION_ENTRY and ending
+   at REGION_EXIT.  */
+
+static void
+mark_loops_in_oacc_kernels_region (basic_block region_entry,
+				   basic_block region_exit)
+{
+  struct loop *outer = region_entry->loop_father;
+  gcc_assert (region_exit == NULL || outer == region_exit->loop_father);
+
+  /* Don't parallelize the kernels region if it contains more than one outer
+     loop.  */
+  unsigned int nr_outer_loops = 0;
+  struct loop *single_outer;
+  for (struct loop *loop = outer->inner; loop != NULL; loop = loop->next)
+    {
+      gcc_assert (loop_outer (loop) == outer);
+
+      if (!dominated_by_p (CDI_DOMINATORS, loop->header, region_entry))
+	continue;
+
+      if (region_exit != NULL
+	  && dominated_by_p (CDI_DOMINATORS, loop->header, region_exit))
+	continue;
+
+      nr_outer_loops++;
+      single_outer = loop;
+    }
+  if (nr_outer_loops != 1)
+    return;
+
+  for (struct loop *loop = single_outer->inner; loop != NULL; loop = loop->inner)
+    if (loop->next)
+      return;
+
+  /* Mark the loops in the region.  */
+  for (struct loop *loop = single_outer; loop != NULL; loop = loop->inner)
+    loop->in_oacc_kernels_region = true;
+}
+
 /* Expand the GIMPLE_OMP_TARGET starting at REGION.  */
 
 static void
@@ -12481,6 +12521,9 @@ expand_omp_target (struct omp_region *region)
   entry_bb = region->entry;
   exit_bb = region->exit;
 
+  if (gimple_omp_target_kind (entry_stmt) == GF_OMP_TARGET_KIND_OACC_KERNELS)
+    mark_loops_in_oacc_kernels_region (region->entry, region->exit);
+
   if (offloaded)
     {
       unsigned srcidx, dstidx, num;