util: Use designated initializers to clean up the format tables' pack/unpack.

[mesa.git] / src / util / bitscan.h

diff --git a/src/util/bitscan.h b/src/util/bitscan.h
index dc89ac93f28b08eed85d54d2aba4484609bc5d50..895a1e7a3721a2f90a22babbcd60eb9fabe1b034 100644 (file)
--- a/src/util/bitscan.h
+++ b/src/util/bitscan.h
@@ -72,7 +72,7 @@ int ffs(int i);
 
 #ifdef HAVE___BUILTIN_FFSLL
 #define ffsll __builtin_ffsll
-#elif defined(_MSC_VER) && (_M_AMD64 || _M_ARM || _M_IA64)
+#elif defined(_MSC_VER) && (_M_AMD64 || _M_ARM64 || _M_IA64)
 static inline int
 ffsll(long long int i)
 {
@@ -235,7 +235,7 @@ util_last_bit64(uint64_t u)
 {
 #if defined(HAVE___BUILTIN_CLZLL)
    return u == 0 ? 0 : 64 - __builtin_clzll(u);
-#elif defined(_MSC_VER) && (_M_AMD64 || _M_ARM || _M_IA64)
+#elif defined(_MSC_VER) && (_M_AMD64 || _M_ARM64 || _M_IA64)
    unsigned long index;
    if (_BitScanReverse64(&index, u))
       return index + 1;
@@ -286,6 +286,38 @@ u_bit_consecutive64(unsigned start, unsigned count)
    return (((uint64_t)1 << count) - 1) << start;
 }
 
+/**
+ * Return number of bits set in n.
+ */
+static inline unsigned
+util_bitcount(unsigned n)
+{
+#if defined(HAVE___BUILTIN_POPCOUNT)
+   return __builtin_popcount(n);
+#else
+   /* K&R classic bitcount.
+    *
+    * For each iteration, clear the LSB from the bitfield.
+    * Requires only one iteration per set bit, instead of
+    * one iteration per bit less than highest set bit.
+    */
+   unsigned bits;
+   for (bits = 0; n; bits++) {
+      n &= n - 1;
+   }
+   return bits;
+#endif
+}
+
+static inline unsigned
+util_bitcount64(uint64_t n)
+{
+#ifdef HAVE___BUILTIN_POPCOUNTLL
+   return __builtin_popcountll(n);
+#else
+   return util_bitcount(n) + util_bitcount(n >> 32);
+#endif
+}
 
 #ifdef __cplusplus
 }