[PATCH] Dump number of loops in a function plus fixup state

[Richard Biener]

I've found this useful several times.  Note that currently
number_of_loops returns loops plus freed ones, the patch prepares
to change that, adjusting number_of_loops callers to use
vec_safe_length if they really want the maximum allocated loop
number.

Bootstrapped on x86_64-unknown-linux-gnu, testing in progress.

Richard.

2016-12-13  Richard Biener  <rguent...@suse.de>

        * cfgloopmanip.c (place_new_loop): Use vec_safe_length to
        get at the maximum allocated loop number.
        * loop-init.c (fix_loop_structure): Likewise.
        * tree-cfg.c (fixup_loop_arrays_after_move): Use place_new_loop.
        (dump_function_to_file): Dump the number of loops in the function
        as well as whether they need fixup.

Index: gcc/cfgloopmanip.c
===================================================================
--- gcc/cfgloopmanip.c  (revision 243599)
+++ gcc/cfgloopmanip.c  (working copy)
@@ -430,7 +430,7 @@ remove_path (edge e, bool *irred_invalid
 void
 place_new_loop (struct function *fn, struct loop *loop)
 {
-  loop->num = number_of_loops (fn);
+  loop->num = vec_safe_length (loops_for_fn (fn)->larray);
   vec_safe_push (loops_for_fn (fn)->larray, loop);
 }
 
Index: gcc/loop-init.c
===================================================================
--- gcc/loop-init.c     (revision 243599)
+++ gcc/loop-init.c     (working copy)
@@ -253,7 +258,7 @@ fix_loop_structure (bitmap changed_bbs)
 
   /* Remember the number of loops so we can return how many new loops
      flow_loops_find discovered.  */
-  old_nloops = number_of_loops (cfun);
+  old_nloops = vec_safe_length (current_loops->larray);
 
   /* Re-compute loop structure in-place.  */
   flow_loops_find (current_loops);
@@ -321,7 +327,7 @@ fix_loop_structure (bitmap changed_bbs)
 
   timevar_pop (TV_LOOP_INIT);
 
-  return number_of_loops (cfun) - old_nloops;
+  return vec_safe_length (current_loops->larray) - old_nloops;
 }
 
 /* The RTL loop superpass.  The actual passes are subpasses.  See passes.c for
Index: gcc/tree-cfg.c
===================================================================
--- gcc/tree-cfg.c      (revision 243597)
+++ gcc/tree-cfg.c      (working copy)
@@ -7095,8 +7095,7 @@ fixup_loop_arrays_after_move (struct fun
   (*get_loops (fn1))[loop->num] = NULL;
 
   /* Place it in the new loop array, assigning it a new number.  */
-  loop->num = number_of_loops (fn2);
-  vec_safe_push (loops_for_fn (fn2)->larray, loop);
+  place_new_loop (fn2, loop);
 
   /* Recurse to children.  */
   for (loop = loop->inner; loop; loop = loop->next)
@@ -7561,7 +7560,14 @@ dump_function_to_file (tree fndecl, FILE
       fprintf (file, " __GIMPLE ()\n%s (", function_name (fun));
     }
   else
-    fprintf (file, "%s %s(", function_name (fun), tmclone ? "[tm-clone] " : 
"");
+    {
+      if (loops_for_fn (fun))
+       fprintf (file, ";; %d loops found%s\n", number_of_loops (fun),
+                loops_for_fn (fun)->state & LOOPS_NEED_FIXUP
+                ? " (fixup required)" : "");
+      fprintf (file, "%s %s(", function_name (fun),
+              tmclone ? "[tm-clone] " : "");
+    }
 
   arg = DECL_ARGUMENTS (fndecl);
   while (arg)