@@ -24,6 +24,7 @@
*/
#include "compiler.h" /* QEMU_GNUC_PREREQ */
+#include <string.h> /* ffsl */
#if defined(__x86_64__)
#define __HAVE_FAST_MULU64__
@@ -234,3 +235,28 @@ static inline int ctpop64(uint64_t val)
return val;
#endif
}
+
+/* glibc does not provide an inline version of ffsl, so always define
+ * ours. We need to give it a different name, however.
+ */
+#ifdef __GLIBC__
+#define ffsl qemu_ffsl
+#endif
+static inline int ffsl(long val)
+{
+ if (!val) {
+ return 0;
+ }
+
+#if QEMU_GNUC_PREREQ(3, 4)
+ return __builtin_ctzl(val) + 1;
+#else
+ if (sizeof(long) == 4) {
+ return ctz32(val) + 1;
+ } else if (sizeof(long) == 8) {
+ return ctz64(val) + 1;
+ } else {
+ abort();
+ }
+#endif
+}
We can provide fast versions based on the other functions defined by host-utils.h. Some care is required on glibc, which provides ffsl already. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> --- host-utils.h | 26 ++++++++++++++++++++++++++ 1 file modificato, 26 inserzioni(+)