This removes the fortunately unused tree_int_cst_msb with its
strange semantics
/* Note that using TYPE_PRECISION here is wrong. We care about the
actual bits, not the (arbitrary) range of the type. */
and "replaces" it by the existing tree_int_cst_sign_bit which has
the expected semantics.
Pending a bootstrap & regtest I'll commit this shortly.
Richard.
2011-08-18 Richard Guenther <rguent...@suse.de>
* tree.h (tree_int_cst_msb): Remove.
* tree.c (tree_int_cst_msb): Likewise.
(tree_int_cst_sign_bit): Move from ...
* tree-ssa-loop-ivopts.c (tree_int_cst_sign_bit): ... here.
Index: trunk/gcc/tree.c
===================================================================
--- trunk.orig/gcc/tree.c 2011-08-18 13:19:16.000000000 +0200
+++ trunk/gcc/tree.c 2011-08-18 13:17:45.000000000 +0200
@@ -6505,21 +6505,23 @@ tree_low_cst (const_tree t, int pos)
return TREE_INT_CST_LOW (t);
}
-/* Return the most significant bit of the integer constant T. */
+/* Return the most significant (sign) bit of T. */
int
-tree_int_cst_msb (const_tree t)
+tree_int_cst_sign_bit (const_tree t)
{
- int prec;
- HOST_WIDE_INT h;
- unsigned HOST_WIDE_INT l;
+ unsigned bitno = TYPE_PRECISION (TREE_TYPE (t)) - 1;
+ unsigned HOST_WIDE_INT w;
- /* Note that using TYPE_PRECISION here is wrong. We care about the
- actual bits, not the (arbitrary) range of the type. */
- prec = GET_MODE_BITSIZE (TYPE_MODE (TREE_TYPE (t))) - 1;
- rshift_double (TREE_INT_CST_LOW (t), TREE_INT_CST_HIGH (t), prec,
- 2 * HOST_BITS_PER_WIDE_INT, &l, &h, 0);
- return (l & 1) == 1;
+ if (bitno < HOST_BITS_PER_WIDE_INT)
+ w = TREE_INT_CST_LOW (t);
+ else
+ {
+ w = TREE_INT_CST_HIGH (t);
+ bitno -= HOST_BITS_PER_WIDE_INT;
+ }
+
+ return (w >> bitno) & 1;
}
/* Return an indication of the sign of the integer constant T.
Index: trunk/gcc/tree-ssa-loop-ivopts.c
===================================================================
--- trunk.orig/gcc/tree-ssa-loop-ivopts.c 2011-08-18 10:35:13.000000000
+0200
+++ trunk/gcc/tree-ssa-loop-ivopts.c 2011-08-18 13:17:48.000000000 +0200
@@ -2892,26 +2892,6 @@ var_at_stmt (struct loop *loop, struct i
return cand->var_before;
}
-/* Return the most significant (sign) bit of T. Similar to tree_int_cst_msb,
- but the bit is determined from TYPE_PRECISION, not MODE_BITSIZE. */
-
-int
-tree_int_cst_sign_bit (const_tree t)
-{
- unsigned bitno = TYPE_PRECISION (TREE_TYPE (t)) - 1;
- unsigned HOST_WIDE_INT w;
-
- if (bitno < HOST_BITS_PER_WIDE_INT)
- w = TREE_INT_CST_LOW (t);
- else
- {
- w = TREE_INT_CST_HIGH (t);
- bitno -= HOST_BITS_PER_WIDE_INT;
- }
-
- return (w >> bitno) & 1;
-}
-
/* If A is (TYPE) BA and B is (TYPE) BB, and the types of BA and BB have the
same precision that is at least as wide as the precision of TYPE, stores
BA to A and BB to B, and returns the type of BA. Otherwise, returns the
Index: trunk/gcc/tree.h
===================================================================
--- trunk.orig/gcc/tree.h 2011-08-18 10:35:13.000000000 +0200
+++ trunk/gcc/tree.h 2011-08-18 13:16:47.000000000 +0200
@@ -4380,7 +4380,6 @@ tree_low_cst (const_tree t, int pos)
return TREE_INT_CST_LOW (t);
}
#endif
-extern int tree_int_cst_msb (const_tree);
extern int tree_int_cst_sgn (const_tree);
extern int tree_int_cst_sign_bit (const_tree);
extern unsigned int tree_int_cst_min_precision (tree, bool);
