re PR rtl-optimization/13985 (ICE in gcc.c-torture/compile/930621-1.c)

	PR optimization/13985
	* cfgloopmanip.c (fix_loop_placements): New prototype.
	Call fix_bb_placements on the preheader of loops that have
	been reparented.
	(remove_path): Adjust call to fix_loop_placements.

From-SVN: r81112

gcc/ChangeLog

+2004-04-23  Eric Botcazou  <ebotcazou@libertysurf.fr>
+
+	PR optimization/13985
+	* cfgloopmanip.c (fix_loop_placements): New prototype.
+	Call fix_bb_placements on the preheader of loops that have
+	been reparented.
+	(remove_path): Adjust call to fix_loop_placements.
+
 2004-04-23  Andrew Pinski  <pinskia@physics.uc.edu>
 
 	* config/darwin7.h: New file.
@@ -241,7 +249,7 @@
 	to "Not triggered by any -O level" section.  Adjust commentary
 	accordingly.
 
-2004-04-20  Anil Paranjpe   <anilp1@kpitcummins.com>
+2004-04-20  Anil Paranjpe <anilp1@kpitcummins.com>
 
 	* toplev.c (compile_file): Move targetm.asm_out.file_end call to end.
 

gcc/cfgloopmanip.c

@@ -41,7 +41,7 @@ static bool rpe_enum_p (basic_block, void *);
 static int find_path (edge, basic_block **);
 static bool alp_enum_p (basic_block, void *);
 static void add_loop (struct loops *, struct loop *);
-static void fix_loop_placements (struct loop *);
+static void fix_loop_placements (struct loops *, struct loop *);
 static bool fix_bb_placement (struct loops *, basic_block);
 static void fix_bb_placements (struct loops *, basic_block);
 static void place_new_loop (struct loops *, struct loop *);
@@ -413,7 +413,7 @@ remove_path (struct loops *loops, edge e)
   /* Fix placements of basic blocks inside loops and the placement of
      loops in the loop tree.  */
   fix_bb_placements (loops, from);
-  fix_loop_placements (from->loop_father);
+  fix_loop_placements (loops, from->loop_father);
 
   return true;
 }
@@ -668,7 +668,7 @@ fix_loop_placement (struct loop *loop)
    It is used in case when we removed some edges coming out of LOOP, which
    may cause the right placement of LOOP inside loop tree to change.  */
 static void
-fix_loop_placements (struct loop *loop)
+fix_loop_placements (struct loops *loops, struct loop *loop)
 {
   struct loop *outer;
 
@@ -677,6 +677,13 @@ fix_loop_placements (struct loop *loop)
       outer = loop->outer;
       if (!fix_loop_placement (loop))
         break;
+
+      /* Changing the placement of a loop in the loop tree may alter the
+	 validity of condition 2) of the description of fix_bb_placement
+	 for its preheader, because the successor is the header and belongs
+	 to the loop.  So call fix_bb_placements to fix up the placement
+	 of the preheader and (possibly) of its predecessors.  */
+      fix_bb_placements (loops, loop_preheader_edge (loop)->src);
       loop = outer;
     }
 }

gcc/testsuite/ChangeLog

+2004-04-23  Eric Botcazou  <ebotcazou@libertysurf.fr>
+
+	* gcc.dg/loop-3.c: New test.
+
 2004-04-23  Daniel Jacobowitz  <drow@mvista.com>
 
 	* gcc.c-torture/execute/simd-5.c: New test.

gcc/testsuite/gcc.dg/loop-3.c

+/* PR optimization/13985 */
+/* Copied from gcc.c-torture/compile/930621-1.c */
+
+/* { dg-do compile } */
+/* { dg-options "-O3" } */
+/* { dg-options "-O3 -mtune=i386" { target i?86-*-* x86_64-*-* } } */
+
+#if defined(STACK_SIZE) && (STACK_SIZE < 65536)
+# define BYTEMEM_SIZE 10000L
+#endif
+
+#ifndef BYTEMEM_SIZE
+# define BYTEMEM_SIZE 45000L
+#endif
+
+int bytestart[5000 + 1];
+unsigned char modtext[400 + 1];
+unsigned char bytemem[2][BYTEMEM_SIZE + 1];
+
+long
+modlookup (int l)
+{
+  signed char c;
+  long j;
+  long k;
+  signed char w;
+  long p;
+  while (p != 0)
+    {
+      while ((k < bytestart[p + 2]) && (j <= l) && (modtext[j] == bytemem[w][k]))
+	{
+	  k = k + 1;
+	  j = j + 1;
+	}
+      if (k == bytestart[p + 2])
+	if (j > l)
+	  c = 1;
+	else c = 4;
+      else if (j > l)
+	c = 3;
+      else if (modtext[j] < bytemem[w][k])
+	c = 0;
+      else c = 2;
+    }
+}