re PR tree-optimization/40087 (Number of iterations analysis wrong)

	PR tree-optimization/40087
	* tree-ssa-loop-niter.c (number_of_iterations_ne_max,
	number_of_iterations_ne): Rename never_infinite argument.
	(number_of_iterations_lt_to_ne, number_of_iterations_lt,
	number_of_iterations_le): Handle pointer-type ivs when
	exit_must_be_taken is false.
	(number_of_iterations_cond):  Do not always assume that
	exit_must_be_taken if the control variable is a pointer.

	* gcc.dg/tree-ssa/pr40087.c: New test.

From-SVN: r147727

gcc/ChangeLog

+2009-05-19  Zdenek Dvorak  <ook@ucw.cz>
+
+	PR tree-optimization/40087
+	* tree-ssa-loop-niter.c (number_of_iterations_ne_max,
+	number_of_iterations_ne): Rename never_infinite argument.
+	(number_of_iterations_lt_to_ne, number_of_iterations_lt,
+	number_of_iterations_le): Handle pointer-type ivs when
+	exit_must_be_taken is false.
+	(number_of_iterations_cond):  Do not always assume that
+	exit_must_be_taken if the control variable is a pointer.
+
 2009-05-19  Andrew Pinski  <andrew_pinski@playstation.sony.com>
 
 	* c-typeck.c (build_binary_op): Allow % on integal vectors.

gcc/testsuite/ChangeLog

+2009-05-19  Zdenek Dvorak  <ook@ucw.cz>
+
+	PR tree-optimization/40087
+	* gcc.dg/tree-ssa/pr40087.c: New test.
+
 2009-05-19  Andrew Pinski  <andrew_pinski@playstation.sony.com>
 
 	* gcc.dg/vector-4.c: New testcase.

gcc/testsuite/gcc.dg/tree-ssa/pr40087.c

+/* { dg-do run } */
+/* { dg-options "-O1 " } */
+
+extern void abort (void);
+
+static void __attribute__((always_inline))
+reverse(int *first, int *last)
+{
+  if (first == last--) 
+    return;
+  while (first != last)
+    {
+      int t = *first;
+      *first = *last;
+      *last = t;
+      if (++first == last--)
+        break;
+    }
+}
+
+int main()
+{
+  int seq[] = { 1, 2, 3, 4, 5, 6, 7, 8 };
+
+  reverse(seq, seq + 8);
+  if (seq[3] != 5 || seq[4] != 4)
+    abort ();
+
+  return 0;
+}