re PR tree-optimization/36508 (ICE in compute_antic)

	PR tree-optimization/36508
	* tree-ssa-pre.c (compute_antic): Allow num_iterations up to
	499, don't check it at all in release compilers.

	* gcc.dg/pr36508.c: New test.

From-SVN: r137036

gcc/ChangeLog

+2008-06-23  Jakub Jelinek  <jakub@redhat.com>
+
+	PR tree-optimization/36508
+	* tree-ssa-pre.c (compute_antic): Allow num_iterations up to
+	499, don't check it at all in release compilers.
+
 2008-06-23  Uros Bizjak  <ubizjak@gmail.com>
 
 	* config/i386/i386.md (*fop_<mode>_1_i387): Use SSE_FLOAT_MODE_P

gcc/testsuite/ChangeLog

+2008-06-23  Jakub Jelinek  <jakub@redhat.com>
+
+	PR tree-optimization/36508
+	* gcc.dg/pr36508.c: New test.
+
 2008-06-20  Joseph Myers  <joseph@codesourcery.com>
 
 	* gcc.dg/inline-31.c: New test.

gcc/testsuite/gcc.dg/pr36508.c

+/* PR tree-optimization/36508 */
+/* { dg-do compile } */
+/* { dg-options "-O -ftree-pre" } */
+
+void
+foo (short *sp)
+{
+  int k;
+  k = 1;
+#define SP0 *sp++ = 1;
+  while (1)
+    {
+      if (k > 6)
+	break;
+      SP0
+      k++;
+    }
+  k = 1;
+  while (1)
+    {
+      if (k > 6)
+	break;
+      SP0
+      k++;
+    }
+#define SP1 SP0 SP0 SP0 SP0 SP0 SP0 SP0 SP0 SP0 SP0 SP0
+#define SP2 SP1 SP1 SP1 SP1 SP1 SP1 SP1 SP1 SP1 SP1 SP1
+  SP2
+}

gcc/tree-ssa-pre.c

@@ -2094,8 +2094,10 @@ compute_antic (void)
 						      block->index));
 	    }
 	}
+#ifdef ENABLE_CHECKING
       /* Theoretically possible, but *highly* unlikely.  */
-      gcc_assert (num_iterations < 50);
+      gcc_assert (num_iterations < 500);
+#endif
     }
 
   statistics_histogram_event (cfun, "compute_antic iterations",
@@ -2124,8 +2126,10 @@ compute_antic (void)
 							    block->index));
 		}
 	    }
+#ifdef ENABLE_CHECKING
 	  /* Theoretically possible, but *highly* unlikely.  */
-	  gcc_assert (num_iterations < 50);
+	  gcc_assert (num_iterations < 500);
+#endif
 	}
       statistics_histogram_event (cfun, "compute_partial_antic iterations",
 				  num_iterations);