--- /dev/null
+/* Copyright (C) 2009 Pierre-Marc Fournier
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library 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 GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#ifndef UST_PROCESSOR_H
+#define UST_PROCESSOR_H
+
+#define ____cacheline_aligned __attribute__((aligned(CAA_CACHE_LINE_SIZE)))
+
+#ifdef __i386
+
+static inline int fls(int x)
+{
+ int r;
+ asm("bsrl %1,%0\n\t"
+ "cmovzl %2,%0"
+ : "=&r" (r) : "rm" (x), "rm" (-1));
+ return r + 1;
+}
+
+#elif defined(__x86_64)
+
+static inline int fls(int x)
+{
+ int r;
+ asm("bsrl %1,%0\n\t"
+ "cmovzl %2,%0"
+ : "=&r" (r) : "rm" (x), "rm" (-1));
+ return r + 1;
+}
+
+#elif defined(__PPC__)
+
+static __inline__ int fls(unsigned int x)
+{
+ int lz;
+
+ asm ("cntlzw %0,%1" : "=r" (lz) : "r" (x));
+ return 32 - lz;
+}
+
+#else /* arch-agnostic */
+
+static __inline__ int fls(unsigned int x)
+{
+ int r = 32;
+
+ if (!x)
+ return 0;
+ if (!(x & 0xFFFF0000U)) {
+ x <<= 16;
+ r -= 16;
+ }
+ if (!(x & 0xFF000000U)) {
+ x <<= 8;
+ r -= 8;
+ }
+ if (!(x & 0xF0000000U)) {
+ x <<= 4;
+ r -= 4;
+ }
+ if (!(x & 0xC0000000U)) {
+ x <<= 2;
+ r -= 2;
+ }
+ if (!(x & 0x80000000U)) {
+ x <<= 1;
+ r -= 1;
+ }
+ return r;
+}
+
+#endif
+
+#endif /* UST_PROCESSOR_H */