gallium/util: libunwind support

[mesa.git] / src / gallium / auxiliary / util / u_math.h

diff --git a/src/gallium/auxiliary/util/u_math.h b/src/gallium/auxiliary/util/u_math.h
index d983af332031369048f123e28e13b77dedb4741c..2ab5f03a6628b79bc4801ad4b1f8d26c1a035aa7 100644 (file)
--- a/src/gallium/auxiliary/util/u_math.h
+++ b/src/gallium/auxiliary/util/u_math.h
@@ -46,10 +46,7 @@
 #include <float.h>
 #include <stdarg.h>
 
-#ifdef PIPE_OS_UNIX
-#include <strings.h> /* for ffs */
-#endif
-
+#include "util/bitscan.h"
 
 #ifdef __cplusplus
 extern "C" {
@@ -349,186 +346,6 @@ util_half_inf_sign(int16_t x)
 }
 
 
-/**
- * Find first bit set in word.  Least significant bit is 1.
- * Return 0 if no bits set.
- */
-#ifndef FFS_DEFINED
-#define FFS_DEFINED 1
-
-#if defined(_MSC_VER) && (_M_IX86 || _M_AMD64 || _M_IA64)
-unsigned char _BitScanForward(unsigned long* Index, unsigned long Mask);
-#pragma intrinsic(_BitScanForward)
-static inline
-unsigned long ffs( unsigned long u )
-{
-   unsigned long i;
-   if (_BitScanForward(&i, u))
-      return i + 1;
-   else
-      return 0;
-}
-#elif defined(PIPE_CC_MSVC) && defined(PIPE_ARCH_X86)
-static inline
-unsigned ffs( unsigned u )
-{
-   unsigned i;
-
-   if (u == 0) {
-      return 0;
-   }
-
-   __asm bsf eax, [u]
-   __asm inc eax
-   __asm mov [i], eax
-
-   return i;
-}
-#elif defined(__MINGW32__) || defined(PIPE_OS_ANDROID) || \
-    defined(HAVE___BUILTIN_FFS)
-#define ffs __builtin_ffs
-#endif
-
-#ifdef HAVE___BUILTIN_FFSLL
-#define ffsll __builtin_ffsll
-#else
-static inline int
-ffsll(long long int val)
-{
-   int bit;
-
-   bit = ffs((unsigned) (val & 0xffffffff));
-   if (bit != 0)
-      return bit;
-
-   bit = ffs((unsigned) (val >> 32));
-   if (bit != 0)
-      return 32 + bit;
-
-   return 0;
-}
-#endif
-
-#endif /* FFS_DEFINED */
-
-/**
- * Find first bit set in long long.  Least significant bit is 1.
- * Return 0 if no bits set.
- */
-#ifndef FFSLL_DEFINED
-#define FFSLL_DEFINED 1
-
-#if defined(__MINGW32__) || defined(PIPE_OS_ANDROID) || \
-    defined(HAVE___BUILTIN_FFSLL)
-#define ffsll __builtin_ffsll
-#endif
-
-#endif /* FFSLL_DEFINED */
-
-/**
- * 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_bit(unsigned u)
-{
-#if defined(HAVE___BUILTIN_CLZ)
-   return u == 0 ? 0 : 32 - __builtin_clz(u);
-#else
-   unsigned r = 0;
-   while (u) {
-       r++;
-       u >>= 1;
-   }
-   return r;
-#endif
-}
-
-/**
- * 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.
- */
-static inline unsigned
-util_last_bit_signed(int i)
-{
-   if (i >= 0)
-      return util_last_bit(i);
-   else
-      return util_last_bit(~(unsigned)i);
-}
-
-/* Destructively loop over all of the bits in a mask as in:
- *
- * while (mymask) {
- *   int i = u_bit_scan(&mymask);
- *   ... process element i
- * }
- *
- */
-static inline int
-u_bit_scan(unsigned *mask)
-{
-   int i = ffs(*mask) - 1;
-   *mask &= ~(1u << i);
-   return i;
-}
-
-#ifndef _MSC_VER
-static inline int
-u_bit_scan64(uint64_t *mask)
-{
-   int i = ffsll(*mask) - 1;
-   *mask &= ~(1llu << i);
-   return i;
-}
-#endif
-
-/* For looping over a bitmask when you want to loop over consecutive bits
- * manually, for example:
- *
- * while (mask) {
- *    int start, count, i;
- *
- *    u_bit_scan_consecutive_range(&mask, &start, &count);
- *
- *    for (i = 0; i < count; i++)
- *       ... process element (start+i)
- * }
- */
-static inline void
-u_bit_scan_consecutive_range(unsigned *mask, int *start, int *count)
-{
-   if (*mask == 0xffffffff) {
-      *start = 0;
-      *count = 32;
-      *mask = 0;
-      return;
-   }
-   *start = ffs(*mask) - 1;
-   *count = ffs(~(*mask >> *start)) - 1;
-   *mask &= ~(((1u << *count) - 1) << *start);
-}
-
 /**
  * Return float bits.
  */
@@ -612,6 +429,18 @@ util_logbase2(unsigned n)
 #endif
 }
 
+/**
+ * Returns the ceiling of log n base 2, and 0 when n == 0. Equivalently,
+ * returns the smallest x such that n <= 2**x.
+ */
+static inline unsigned
+util_logbase2_ceil(unsigned n)
+{
+   if (n <= 1)
+      return 0;
+
+   return 1 + util_logbase2(n - 1);
+}
 
 /**
  * Returns the smallest power of two >= x
@@ -801,7 +630,7 @@ align(int value, int alignment)
 static inline uint64_t
 align64(uint64_t value, unsigned alignment)
 {
-   return (value + alignment - 1) & ~(alignment - 1);
+   return (value + alignment - 1) & ~((uint64_t)alignment - 1);
 }
 
 /**