[wide-int] Remove SHIFT_COUNT_TRUNCATED uses at tree/gimple level

[Richard Sandiford]

Following the removal of SHIFT_COUNT_TRUNCATED from double-int, this patch
reverts the changed I'd made to mimic the old behaviour on wide-int.

Tested on powerpc64-linux-gnu and by assembly comparison on a range of targets.
OK to install?

Thanks,
Richard


Index: gcc/fold-const.c
===================================================================
--- gcc/fold-const.c    2013-11-05 13:06:56.985255941 +0000
+++ gcc/fold-const.c    2013-11-05 13:12:28.805655903 +0000
@@ -1007,13 +1007,9 @@ int_const_binop_1 (enum tree_code code,
        /* It's unclear from the C standard whether shifts can overflow.
           The following code ignores overflow; perhaps a C standard
           interpretation ruling is needed.  */
-       res = wi::rshift (arg1, arg2, sign,
-                         SHIFT_COUNT_TRUNCATED
-                         ? GET_MODE_BITSIZE (TYPE_MODE (type)) : 0);
+       res = wi::rshift (arg1, arg2, sign);
       else
-       res = wi::lshift (arg1, arg2,
-                         SHIFT_COUNT_TRUNCATED
-                         ? GET_MODE_BITSIZE (TYPE_MODE (type)) : 0);
+       res = wi::lshift (arg1, arg2);
       break;
       
     case RROTATE_EXPR:
Index: gcc/tree-ssa-ccp.c
===================================================================
--- gcc/tree-ssa-ccp.c  2013-11-05 13:07:25.659474362 +0000
+++ gcc/tree-ssa-ccp.c  2013-11-05 13:12:28.806655910 +0000
@@ -1272,20 +1272,15 @@ bit_value_binop_1 (enum tree_code code,
                  else
                    code = RSHIFT_EXPR;
                }
-             int shift_precision = SHIFT_COUNT_TRUNCATED ? width : 0;
              if (code == RSHIFT_EXPR)
                {
-                 *mask = wi::rshift (wi::ext (r1mask, width, sgn),
-                                     shift, sgn, shift_precision);
-                 *val = wi::rshift (wi::ext (r1val, width, sgn),
-                                    shift, sgn, shift_precision);
+                 *mask = wi::rshift (wi::ext (r1mask, width, sgn), shift, sgn);
+                 *val = wi::rshift (wi::ext (r1val, width, sgn), shift, sgn);
                }
              else
                {
-                 *mask = wi::ext (wi::lshift (r1mask, shift, shift_precision),
-                                  width, sgn);
-                 *val = wi::ext (wi::lshift (r1val, shift, shift_precision),
-                                 width, sgn);
+                 *mask = wi::ext (wi::lshift (r1mask, shift), width, sgn);
+                 *val = wi::ext (wi::lshift (r1val, shift), width, sgn);
                }
            }
        }