[gcc r12-1552] Add debugging helpers for ranger.

[Aldy Hernandez <aldyh@gcc.gnu.org>]

https://gcc.gnu.org/g:3f3ee13959f852de432fa7761a8e50ddee6d6e1b

commit r12-1552-g3f3ee13959f852de432fa7761a8e50ddee6d6e1b
Author: Aldy Hernandez <aldyh@redhat.com>
Date:   Mon Jun 14 11:39:33 2021 +0200

    Add debugging helpers for ranger.
    
    These are debugging aids for help in debugging ranger based passes.
    
    gcc/ChangeLog:
    
            * gimple-range.cc (debug_seed_ranger): New.
            (dump_ranger): New.
            (debug_ranger): New.

Diff:
---
 gcc/gimple-range.cc | 79 +++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 79 insertions(+)

diff --git a/gcc/gimple-range.cc b/gcc/gimple-range.cc
index efb919f1595..58109701f2f 100644
--- a/gcc/gimple-range.cc
+++ b/gcc/gimple-range.cc
@@ -1662,4 +1662,83 @@ disable_ranger (struct function *fun)
   fun->x_range_query = &global_ranges;
 }
 
+// =========================================
+// Debugging helpers.
+// =========================================
+
+// Query all statements in the IL to precalculate computable ranges in RANGER.
+
+static DEBUG_FUNCTION void
+debug_seed_ranger (gimple_ranger &ranger)
+{
+  // Recalculate SCEV to make sure the dump lists everything.
+  if (scev_initialized_p ())
+    {
+      scev_finalize ();
+      scev_initialize ();
+    }
+
+  basic_block bb;
+  int_range_max r;
+  gimple_stmt_iterator gsi;
+  FOR_EACH_BB_FN (bb, cfun)
+    for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
+      {
+	gimple *stmt = gsi_stmt (gsi);
+
+	if (is_gimple_debug (stmt))
+	  continue;
+
+	ranger.range_of_stmt (r, stmt);
+      }
+}
+
+// Dump all that ranger knows for the current function.
+
+DEBUG_FUNCTION void
+dump_ranger (FILE *out)
+{
+  gimple_ranger ranger;
+  debug_seed_ranger (ranger);
+  ranger.dump (out);
+}
+
+DEBUG_FUNCTION void
+debug_ranger ()
+{
+  dump_ranger (stderr);
+}
+
+// Dump all that ranger knows on a path of BBs.
+//
+// Note that the blocks are in reverse order, thus the exit block is
+// path[0].
+
+DEBUG_FUNCTION void
+dump_ranger (FILE *dump_file, const vec<basic_block> &path)
+{
+  if (path.length () == 0)
+    {
+      fprintf (dump_file, "empty\n");
+      return;
+    }
+
+  gimple_ranger ranger;
+  debug_seed_ranger (ranger);
+
+  unsigned i = path.length ();
+  do
+    {
+      i--;
+      ranger.dump_bb (dump_file, path[i]);
+    }
+  while (i > 0);
+}
+
+DEBUG_FUNCTION void
+debug_ranger (const vec<basic_block> &path)
+{
+  dump_ranger (stderr, path);
+}
+
 #include "gimple-range-tests.cc"