bitops: rename bit scan functions

[wimlib] / include / wimlib / compiler.h

diff --git a/include/wimlib/compiler.h b/include/wimlib/compiler.h
index c469010bdfa86e178274a7a1d5b64ced21e7d068..6bce5d0152e11742905461df5d1b6fcc1b71411d 100644 (file)
--- a/include/wimlib/compiler.h
+++ b/include/wimlib/compiler.h
@@ -3,8 +3,21 @@
  *
  * Compiler-specific definitions.  Currently, only GCC and clang are supported.
  *
- * The author dedicates this file to the public domain.
- * You can do whatever you want with this file.
+ * The following copying information applies to this specific source code file:
+ *
+ * Written in 2013-2016 by Eric Biggers <ebiggers3@gmail.com>
+ *
+ * To the extent possible under law, the author(s) have dedicated all copyright
+ * and related and neighboring rights to this software to the public domain
+ * worldwide via the Creative Commons Zero 1.0 Universal Public Domain
+ * Dedication (the "CC0").
+ *
+ * This software is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+ * FOR A PARTICULAR PURPOSE. See the CC0 for more details.
+ *
+ * You should have received a copy of the CC0 along with this software; if not
+ * see <http://creativecommons.org/publicdomain/zero/1.0/>.
  */
 
 #ifndef _WIMLIB_COMPILER_H
@@ -84,8 +97,15 @@
  * returns will not alias any pointer previously in use by the program.  */
 #define _malloc_attribute      __attribute__((malloc))
 
-/* TODO: _format_attribute is currently ignored.  */
-#define _format_attribute(type, format_str, format_start)
+/* Hint that the annotated function takes a printf()-like format string and
+ * arguments.  This is currently disabled on Windows because MinGW does not
+ * support this attribute on functions taking wide-character strings.  */
+#ifdef __WIN32__
+#  define _format_attribute(type, format_str, format_start)
+#else
+#  define _format_attribute(type, format_str, format_start)    \
+                       __attribute__((format(type, format_str, format_start)))
+#endif
 
 /* Hint that the annotated function is intentionally not used.  This might be
  * the case if the function contains only static assertions.  */
@@ -151,10 +171,10 @@
 #endif
 
 /* (Optional) Find Last Set bit and Find First Set bit macros.  */
-#define compiler_fls32(n)      (31 - __builtin_clz(n))
-#define compiler_fls64(n)      (63 - __builtin_clzll(n))
-#define compiler_ffs32(n)      __builtin_ctz(n)
-#define compiler_ffs64(n)      __builtin_ctzll(n)
+#define compiler_bsr32(n)      (31 - __builtin_clz(n))
+#define compiler_bsr64(n)      (63 - __builtin_clzll(n))
+#define compiler_bsf32(n)      __builtin_ctz(n)
+#define compiler_bsf64(n)      __builtin_ctzll(n)
 
 /* Optional definitions for checking with 'sparse'.  */
 #ifdef __CHECKER__
@@ -172,6 +192,10 @@
 #  define STATIC_ASSERT(expr)  ((void)sizeof(char[1 - 2 * !(expr)]))
 #endif
 
+/* STATIC_ASSERT_ZERO() - verify the truth of an expression at compilation time
+ * and also produce a result of value '0' to be used in constant expressions */
+#define STATIC_ASSERT_ZERO(expr) ((int)sizeof(char[-!(expr)]))
+
 #define CONCAT_IMPL(s1, s2)    s1##s2
 
 /* CONCAT() - concatenate two tokens at preprocessing time.  */