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-rw-r--r--mesalib/src/gallium/auxiliary/util/u_math.h20
1 files changed, 20 insertions, 0 deletions
diff --git a/mesalib/src/gallium/auxiliary/util/u_math.h b/mesalib/src/gallium/auxiliary/util/u_math.h
index 3d27a59e8..3b4040f0e 100644
--- a/mesalib/src/gallium/auxiliary/util/u_math.h
+++ b/mesalib/src/gallium/auxiliary/util/u_math.h
@@ -42,6 +42,7 @@
#include "pipe/p_compiler.h"
#include "c99_math.h"
+#include <assert.h>
#include <float.h>
#include <stdarg.h>
@@ -424,6 +425,25 @@ util_last_bit(unsigned u)
}
/**
+ * Find last bit set in a word. The least significant bit is 1.
+ * Return 0 if no bits are set.
+ */
+static INLINE unsigned
+util_last_bit64(uint64_t u)
+{
+#if defined(HAVE___BUILTIN_CLZLL)
+ return u == 0 ? 0 : 64 - __builtin_clzll(u);
+#else
+ unsigned r = 0;
+ while (u) {
+ r++;
+ u >>= 1;
+ }
+ return r;
+#endif
+}
+
+/**
* Find last bit in a word that does not match the sign bit. The least
* significant bit is 1.
* Return 0 if no bits are set.