[gcc/devel/omp/gcc-11] openacc: Add "can_be_parallel" flag info to "graph" dumps

[Frederik Harwath <frederik@gcc.gnu.org>]

https://gcc.gnu.org/g:dce1c32758dbdba9b09ba4f9aae10b85cb0e8a55

commit dce1c32758dbdba9b09ba4f9aae10b85cb0e8a55
Author: Frederik Harwath <frederik@codesourcery.com>
Date:   Tue Nov 16 16:16:47 2021 +0100

    openacc: Add "can_be_parallel" flag info to "graph" dumps
    
    gcc/ChangeLog:
    
            * graph.c (oacc_get_fn_attrib): New declaration.
            (find_loop_location): New declaration.
            (draw_cfg_nodes_for_loop): Print value of the
            can_be_parallel flag at the top of loops in OpenACC
            functions.

Diff:
---
 gcc/graph.c | 35 ++++++++++++++++++++++++-----------
 1 file changed, 24 insertions(+), 11 deletions(-)

diff --git a/gcc/graph.c b/gcc/graph.c
index ce8de33ffe1..3ad07be3b30 100644
--- a/gcc/graph.c
+++ b/gcc/graph.c
@@ -191,6 +191,10 @@ draw_cfg_nodes_no_loops (pretty_printer *pp, struct function *fun)
     }
 }
 
+
+extern tree oacc_get_fn_attrib (tree);
+extern dump_user_location_t find_loop_location (class loop *);
+
 /* Draw all the basic blocks in LOOP.  Print the blocks in breath-first
    order to get a good ranking of the nodes.  This function is recursive:
    It first prints inner loops, then the body of LOOP itself.  */
@@ -205,17 +209,26 @@ draw_cfg_nodes_for_loop (pretty_printer *pp, int funcdef_no,
 
   if (loop->header != NULL
       && loop->latch != EXIT_BLOCK_PTR_FOR_FN (cfun))
-    pp_printf (pp,
-	       "\tsubgraph cluster_%d_%d {\n"
-	       "\tstyle=\"filled\";\n"
-	       "\tcolor=\"darkgreen\";\n"
-	       "\tfillcolor=\"%s\";\n"
-	       "\tlabel=\"loop %d\";\n"
-	       "\tlabeljust=l;\n"
-	       "\tpenwidth=2;\n",
-	       funcdef_no, loop->num,
-	       fillcolors[(loop_depth (loop) - 1) % 3],
-	       loop->num);
+    {
+      pp_printf (pp,
+                 "\tsubgraph cluster_%d_%d {\n"
+                 "\tstyle=\"filled\";\n"
+                 "\tcolor=\"darkgreen\";\n"
+                 "\tfillcolor=\"%s\";\n"
+                 "\tlabel=\"loop %d %s\";\n"
+                 "\tlabeljust=l;\n"
+                 "\tpenwidth=2;\n",
+                 funcdef_no, loop->num,
+                 fillcolors[(loop_depth (loop) - 1) % 3], loop->num,
+                 /* This is only meaningful for loops that have been processed
+                    by Graphite.
+
+                    TODO Use can_be_parallel_valid_p? */
+                 !oacc_get_fn_attrib (cfun->decl)
+                     ? ""
+                     : loop->can_be_parallel ? "(can_be_parallel = true)"
+                                             : "(can_be_parallel = false)");
+    }
 
   for (class loop *inner = loop->inner; inner; inner = inner->next)
     draw_cfg_nodes_for_loop (pp, funcdef_no, inner);