trans.c (can_equal_min_or_max_val_p): Be prepared for values outside of the range of the type.

* gcc-interface/trans.c (can_equal_min_or_max_val_p): Be prepared for
	values outside of the range of the type.

From-SVN: r201692

gcc/ada/ChangeLog

@@ -1,3 +1,8 @@
+2013-08-13  Eric Botcazou  <ebotcazou@adacore.com>
+
+	* gcc-interface/trans.c (can_equal_min_or_max_val_p): Be prepared for
+	values outside of the range of the type.
+
 2013-08-13  Eric Botcazou  <ebotcazou@adacore.com>
 
 	* gcc-interface/utils2.c (build_atomic_load): Do a mere view-conversion

gcc/ada/gcc-interface/trans.c

@@ -2391,7 +2391,10 @@ can_equal_min_or_max_val_p (tree val, tree type, bool max)
   if (TREE_CODE (val) != INTEGER_CST)
     return true;
 
-  return tree_int_cst_equal (val, min_or_max_val) == 1;
+  if (max)
+    return tree_int_cst_lt (val, min_or_max_val) == 0;
+  else
+    return tree_int_cst_lt (min_or_max_val, val) == 0;
 }
 
 /* Return true if VAL (of type TYPE) can equal the minimum value of TYPE.

gcc/testsuite/ChangeLog

@@ -1,3 +1,8 @@
+2013-08-13  Eric Botcazou  <ebotcazou@adacore.com>
+
+	* gnat.dg/loop_optimization16.adb: New test.
+	* gnat.dg/loop_optimization16_pkg.ad[sb]: New helper.
+
 2013-08-13  Marek Polacek  <polacek@redhat.com>
 
 	* gcc.dg/pr57980.c: Use vector of two elements, not just one.

gcc/testsuite/gnat.dg/loop_optimization16.adb

@@ -0,0 +1,24 @@
+-- { dg-do run }
+
+with Loop_Optimization16_Pkg; use Loop_Optimization16_Pkg;
+
+procedure Loop_Optimization16 is
+
+   Counter : Natural := 0;
+
+   C : constant Natural := F;
+
+   subtype Index_T is Index_Base range 1 .. Index_Base (C);
+
+begin
+
+   for I in Index_T'First .. Index_T'Last loop
+      Counter := Counter + 1;
+      exit when Counter > 200;
+   end loop;
+
+   if Counter > 200 then
+      raise Program_Error;
+   end if;
+
+end Loop_Optimization16;

gcc/testsuite/gnat.dg/loop_optimization16_pkg.adb

@@ -0,0 +1,8 @@
+package body Loop_Optimization16_Pkg is
+
+  function F return Natural is
+  begin
+    return Natural (Index_Base'Last);
+  end;
+
+end Loop_Optimization16_Pkg;

gcc/testsuite/gnat.dg/loop_optimization16_pkg.ads

@@ -0,0 +1,7 @@
+package Loop_Optimization16_Pkg is
+
+  type Index_Base is range 0 .. 127;
+
+  function F return Natural;
+
+end Loop_Optimization16_Pkg;