X-Git-Url: http://erislabs.net/gitweb/?a=blobdiff_plain;f=lib%2Fcount-one-bits.h;h=97b0f8a3f4bf4b508c31a73ca44d3f86cd26fc38;hb=7ef6c64e210ac0979d7e8ac69bc5b5208c2405ab;hp=7553bec4ecbfc850f62901ac1fbcf0b96eb99453;hpb=e9cfd9f2d0d75d5d09d0acff6cb578a5c039c45c;p=gnulib.git
diff --git a/lib/count-one-bits.h b/lib/count-one-bits.h
index 7553bec4e..97b0f8a3f 100644
--- a/lib/count-one-bits.h
+++ b/lib/count-one-bits.h
@@ -1,10 +1,10 @@
/* count-one-bits.h -- counts the number of 1-bits in a word.
- Copyright (C) 2007 Free Software Foundation, Inc.
+ Copyright (C) 2007-2014 Free Software Foundation, Inc.
- This program is free software; you can redistribute it and/or modify
+ This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
- the Free Software Foundation; either version 2, or (at your option)
- any later version.
+ the Free Software Foundation; either version 3 of the License, or
+ (at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
@@ -12,32 +12,52 @@
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
- along with this program; if not, write to the Free Software Foundation,
- Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */
+ along with this program. If not, see . */
/* Written by Ben Pfaff. */
#ifndef COUNT_ONE_BITS_H
-# define COUNT_ONE_BITS_H 1
+#define COUNT_ONE_BITS_H 1
#include
#include
-#include "verify.h"
-#if __GNUC__ > 3 || (__GNUC__ == 3 && __GNUC_MINOR >= 4)
-#define COUNT_ONE_BITS(BUILTIN, TYPE) \
- return BUILTIN (x);
+#ifndef _GL_INLINE_HEADER_BEGIN
+ #error "Please include config.h first."
+#endif
+_GL_INLINE_HEADER_BEGIN
+#ifndef COUNT_ONE_BITS_INLINE
+# define COUNT_ONE_BITS_INLINE _GL_INLINE
+#endif
+
+/* Expand to code that computes the number of 1-bits of the local
+ variable 'x' of type TYPE (an unsigned integer type) and return it
+ from the current function. */
+#define COUNT_ONE_BITS_GENERIC(TYPE) \
+ do \
+ { \
+ int count = 0; \
+ int bits; \
+ for (bits = 0; bits < sizeof (TYPE) * CHAR_BIT; bits += 32) \
+ { \
+ count += count_one_bits_32 (x); \
+ x = x >> 31 >> 1; \
+ } \
+ return count; \
+ } \
+ while (0)
+
+/* Assuming the GCC builtin is BUILTIN and the MSC builtin is MSC_BUILTIN,
+ expand to code that computes the number of 1-bits of the local
+ variable 'x' of type TYPE (an unsigned integer type) and return it
+ from the current function. */
+#if __GNUC__ > 3 || (__GNUC__ == 3 && __GNUC_MINOR__ >= 4)
+# define COUNT_ONE_BITS(BUILTIN, MSC_BUILTIN, TYPE) return BUILTIN (x)
#else
-#define COUNT_ONE_BITS(BUILTIN, TYPE) \
- int count = count_one_bits_32 (x); \
- if (CHAR_BIT * sizeof (TYPE) > 32) \
- count += count_one_bits_32 (x >> 31 >> 1); \
- (void) verify_true (CHAR_BIT * sizeof (TYPE) <= 64); \
- return count;
-
-/* Compute and return the the number of 1-bits set in the least
+
+/* Compute and return the number of 1-bits set in the least
significant 32 bits of X. */
-static inline int
+COUNT_ONE_BITS_INLINE int
count_one_bits_32 (unsigned int x)
{
x = ((x & 0xaaaaaaaaU) >> 1) + (x & 0x55555555U);
@@ -46,29 +66,71 @@ count_one_bits_32 (unsigned int x)
x = ((x & 0xf0f0) >> 4) + (x & 0x0f0f);
return (x >> 8) + (x & 0x00ff);
}
+
+# if 1500 <= _MSC_VER && (defined _M_IX86 || defined _M_X64)
+
+/* While gcc falls back to its own generic code if the machine
+ on which it's running doesn't support popcount, with Microsoft's
+ compiler we need to detect and fallback ourselves. */
+# pragma intrinsic __cpuid
+# pragma intrinsic __popcnt
+# pragma intrinsic __popcnt64
+
+/* Return nonzero if popcount is supported. */
+
+/* 1 if supported, 0 if not supported, -1 if unknown. */
+extern int popcount_support;
+
+COUNT_ONE_BITS_INLINE int
+popcount_supported (void)
+{
+ if (popcount_support < 0)
+ {
+ int cpu_info[4];
+ __cpuid (cpu_info, 1);
+ popcount_support = (cpu_info[2] >> 23) & 1; /* See MSDN. */
+ }
+ return popcount_support;
+}
+
+# define COUNT_ONE_BITS(BUILTIN, MSC_BUILTIN, TYPE) \
+ do \
+ { \
+ if (popcount_supported ()) \
+ return MSC_BUILTIN (x); \
+ else \
+ COUNT_ONE_BITS_GENERIC (TYPE); \
+ } \
+ while (0)
+# else
+# define COUNT_ONE_BITS(BUILTIN, MSC_BUILTIN, TYPE) \
+ COUNT_ONE_BITS_GENERIC (TYPE)
+# endif
#endif
/* Compute and return the number of 1-bits set in X. */
-static inline int
+COUNT_ONE_BITS_INLINE int
count_one_bits (unsigned int x)
{
- COUNT_ONE_BITS (__builtin_popcount, unsigned int);
+ COUNT_ONE_BITS (__builtin_popcount, __popcnt, unsigned int);
}
/* Compute and return the number of 1-bits set in X. */
-static inline int
+COUNT_ONE_BITS_INLINE int
count_one_bits_l (unsigned long int x)
{
- COUNT_ONE_BITS (__builtin_popcountl, unsigned long int);
+ COUNT_ONE_BITS (__builtin_popcountl, __popcnt, unsigned long int);
}
#if HAVE_UNSIGNED_LONG_LONG_INT
/* Compute and return the number of 1-bits set in X. */
-static inline int
+COUNT_ONE_BITS_INLINE int
count_one_bits_ll (unsigned long long int x)
{
- COUNT_ONE_BITS (__builtin_popcountll, unsigned long long int);
+ COUNT_ONE_BITS (__builtin_popcountll, __popcnt64, unsigned long long int);
}
#endif
+_GL_INLINE_HEADER_END
+
#endif /* COUNT_ONE_BITS_H */