From 4616ef9b8517396fc1b4edd6d1fcdbe3705c0892 Mon Sep 17 00:00:00 2001
From: Mikael Morin <mikael@gcc.gnu.org>
Date: Thu, 3 Nov 2011 23:45:19 +0000
Subject: [PATCH] trans.h (struct gfc_loopinfo): New field parent.

	* trans.h (struct gfc_loopinfo): New field parent.
	* trans-array.c (gfc_cleanup_loop): Free nested loops.
	(gfc_add_ss_to_loop): Set nested_loop's parent loop.
	(gfc_trans_array_constructor): Update assertion.
	(gfc_conv_loop_setup): Ditto.

From-SVN: r180899
---
 gcc/fortran/ChangeLog     |  8 ++++++++
 gcc/fortran/trans-array.c | 25 +++++++++++++++++++++++++
 gcc/fortran/trans.h       |  3 +++
 3 files changed, 36 insertions(+)

diff --git a/gcc/fortran/ChangeLog b/gcc/fortran/ChangeLog
index 653b262b81d..89ba5847fde 100644
--- a/gcc/fortran/ChangeLog
+++ b/gcc/fortran/ChangeLog
@@ -1,3 +1,11 @@
+2011-11-03  Mikael Morin  <mikael@gcc.gnu.org>
+
+	* trans.h (struct gfc_loopinfo): New field parent.
+	* trans-array.c (gfc_cleanup_loop): Free nested loops.
+	(gfc_add_ss_to_loop): Set nested_loop's parent loop.
+	(gfc_trans_array_constructor): Update assertion.
+	(gfc_conv_loop_setup): Ditto.
+
 2011-11-03  Mikael Morin  <mikael@gcc.gnu.org>
 
 	* trans-array.c (gfc_add_loop_ss_code): Skip non-nestedmost ss.
diff --git a/gcc/fortran/trans-array.c b/gcc/fortran/trans-array.c
index 27356a1a1d3..5659b70846e 100644
--- a/gcc/fortran/trans-array.c
+++ b/gcc/fortran/trans-array.c
@@ -604,6 +604,7 @@ gfc_get_scalar_ss (gfc_ss *next, gfc_expr *expr)
 void
 gfc_cleanup_loop (gfc_loopinfo * loop)
 {
+  gfc_loopinfo *loop_next, **ploop;
   gfc_ss *ss;
   gfc_ss *next;
 
@@ -615,6 +616,23 @@ gfc_cleanup_loop (gfc_loopinfo * loop)
       gfc_free_ss (ss);
       ss = next;
     }
+
+  /* Remove reference to self in the parent loop.  */
+  if (loop->parent)
+    for (ploop = &loop->parent->nested; *ploop; ploop = &(*ploop)->next)
+      if (*ploop == loop)
+	{
+	  *ploop = loop->next;
+	  break;
+	}
+
+  /* Free non-freed nested loops.  */
+  for (loop = loop->nested; loop; loop = loop_next)
+    {
+      loop_next = loop->next;
+      gfc_cleanup_loop (loop);
+      free (loop);
+    }
 }
 
 
@@ -664,10 +682,15 @@ gfc_add_ss_to_loop (gfc_loopinfo * loop, gfc_ss * head)
 	     added one, to avoid duplicate nested loops.  */
 	  if (nested_loop != loop->nested)
 	    {
+	      gcc_assert (nested_loop->parent == NULL);
+	      nested_loop->parent = loop;
+
 	      gcc_assert (nested_loop->next == NULL);
 	      nested_loop->next = loop->nested;
 	      loop->nested = nested_loop;
 	    }
+	  else
+	    gcc_assert (nested_loop->parent == loop);
 	}
 
       if (ss->next == gfc_ss_terminator)
@@ -2158,6 +2181,7 @@ trans_array_constructor (gfc_ss * ss, locus * where)
       mpz_t size;
 
       /* We should have a 1-dimensional, zero-based loop.  */
+      gcc_assert (loop->parent == NULL && loop->nested == NULL);
       gcc_assert (loop->dimen == 1);
       gcc_assert (integer_zerop (loop->from[0]));
 
@@ -4302,6 +4326,7 @@ gfc_conv_loop_setup (gfc_loopinfo * loop, locus * where)
 
       tmp_ss_info = tmp_ss->info;
       gcc_assert (tmp_ss_info->type == GFC_SS_TEMP);
+      gcc_assert (loop->parent == NULL);
 
       /* Make absolutely sure that this is a complete type.  */
       if (tmp_ss_info->string_length)
diff --git a/gcc/fortran/trans.h b/gcc/fortran/trans.h
index 0549aa79301..4d745f144ce 100644
--- a/gcc/fortran/trans.h
+++ b/gcc/fortran/trans.h
@@ -279,6 +279,9 @@ typedef struct gfc_loopinfo
   /* The SS describing the temporary used in an assignment.  */
   gfc_ss *temp_ss;
 
+  /* Non-null if this loop is nested in another one.  */
+  struct gfc_loopinfo *parent;
+
   /* Chain of nested loops.  */
   struct gfc_loopinfo *nested, *next;
 
-- 
2.30.2