aboutsummaryrefslogtreecommitdiff
path: root/gcc/hwint.h
diff options
context:
space:
mode:
Diffstat (limited to 'gcc/hwint.h')
-rw-r--r--gcc/hwint.h73
1 files changed, 72 insertions, 1 deletions
diff --git a/gcc/hwint.h b/gcc/hwint.h
index c7fcd34..8bd7c5e 100644
--- a/gcc/hwint.h
+++ b/gcc/hwint.h
@@ -1,5 +1,6 @@
/* HOST_WIDE_INT definitions for the GNU compiler.
- Copyright (C) 1998, 2002, 2004, 2008, 2009 Free Software Foundation, Inc.
+ Copyright (C) 1998, 2002, 2004, 2008, 2009, 2010
+ Free Software Foundation, Inc.
This file is part of GCC.
@@ -157,4 +158,74 @@ extern char sizeof_long_long_must_be_8[sizeof(long long) == 8 ? 1 : -1];
# define HOST_BITS_PER_WIDEST_FAST_INT HOST_BITS_PER_LONG
#endif
+/* Inline functions operating on HOST_WIDE_INT. */
+#if GCC_VERSION < 3004
+
+extern int clz_hwi (unsigned HOST_WIDE_INT x);
+extern int ctz_hwi (unsigned HOST_WIDE_INT x);
+extern int ffs_hwi (unsigned HOST_WIDE_INT x);
+
+/* Return log2, or -1 if not exact. */
+extern int exact_log2 (unsigned HOST_WIDE_INT);
+
+/* Return floor of log2, with -1 for zero. */
+extern int floor_log2 (unsigned HOST_WIDE_INT);
+
+#else /* GCC_VERSION >= 3004 */
+
+/* For convenience, define 0 -> word_size. */
+static inline int
+clz_hwi (unsigned HOST_WIDE_INT x)
+{
+ if (x == 0)
+ return HOST_BITS_PER_WIDE_INT;
+# if HOST_BITS_PER_WIDE_INT == HOST_BITS_PER_LONG
+ return __builtin_clzl (x);
+# elif HOST_BITS_PER_WIDE_INT == HOST_BITS_PER_LONGLONG
+ return __builtin_clzll (x);
+# else
+ return __builtin_clz (x);
+# endif
+}
+
+static inline int
+ctz_hwi (unsigned HOST_WIDE_INT x)
+{
+ if (x == 0)
+ return HOST_BITS_PER_WIDE_INT;
+# if HOST_BITS_PER_WIDE_INT == HOST_BITS_PER_LONG
+ return __builtin_ctzl (x);
+# elif HOST_BITS_PER_WIDE_INT == HOST_BITS_PER_LONGLONG
+ return __builtin_ctzll (x);
+# else
+ return __builtin_ctz (x);
+# endif
+}
+
+static inline int
+ffs_hwi (unsigned HOST_WIDE_INT x)
+{
+# if HOST_BITS_PER_WIDE_INT == HOST_BITS_PER_LONG
+ return __builtin_ffsl (x);
+# elif HOST_BITS_PER_WIDE_INT == HOST_BITS_PER_LONGLONG
+ return __builtin_ffsll (x);
+# else
+ return __builtin_ffs (x);
+# endif
+}
+
+static inline int
+floor_log2 (unsigned HOST_WIDE_INT x)
+{
+ return HOST_BITS_PER_WIDE_INT - 1 - clz_hwi (x);
+}
+
+static inline int
+exact_log2 (unsigned HOST_WIDE_INT x)
+{
+ return x == (x & -x) && x ? ctz_hwi (x) : -1;
+}
+
+#endif /* GCC_VERSION >= 3004 */
+
#endif /* ! GCC_HWINT_H */