Index: xz/src/common/tuklib_integer.h |
=================================================================== |
--- xz/src/common/tuklib_integer.h (revision 0) |
+++ xz/src/common/tuklib_integer.h (revision 0) |
@@ -0,0 +1,523 @@ |
+/////////////////////////////////////////////////////////////////////////////// |
+// |
+/// \file tuklib_integer.h |
+/// \brief Various integer and bit operations |
+/// |
+/// This file provides macros or functions to do some basic integer and bit |
+/// operations. |
+/// |
+/// Endianness related integer operations (XX = 16, 32, or 64; Y = b or l): |
+/// - Byte swapping: bswapXX(num) |
+/// - Byte order conversions to/from native: convXXYe(num) |
+/// - Aligned reads: readXXYe(ptr) |
+/// - Aligned writes: writeXXYe(ptr, num) |
+/// - Unaligned reads (16/32-bit only): unaligned_readXXYe(ptr) |
+/// - Unaligned writes (16/32-bit only): unaligned_writeXXYe(ptr, num) |
+/// |
+/// Since they can macros, the arguments should have no side effects since |
+/// they may be evaluated more than once. |
+/// |
+/// \todo PowerPC and possibly some other architectures support |
+/// byte swapping load and store instructions. This file |
+/// doesn't take advantage of those instructions. |
+/// |
+/// Bit scan operations for non-zero 32-bit integers: |
+/// - Bit scan reverse (find highest non-zero bit): bsr32(num) |
+/// - Count leading zeros: clz32(num) |
+/// - Count trailing zeros: ctz32(num) |
+/// - Bit scan forward (simply an alias for ctz32()): bsf32(num) |
+/// |
+/// The above bit scan operations return 0-31. If num is zero, |
+/// the result is undefined. |
+// |
+// Authors: Lasse Collin |
+// Joachim Henke |
+// |
+// This file has been put into the public domain. |
+// You can do whatever you want with this file. |
+// |
+/////////////////////////////////////////////////////////////////////////////// |
+ |
+#ifndef TUKLIB_INTEGER_H |
+#define TUKLIB_INTEGER_H |
+ |
+#include "tuklib_common.h" |
+ |
+ |
+//////////////////////////////////////// |
+// Operating system specific features // |
+//////////////////////////////////////// |
+ |
+#if defined(HAVE_BYTESWAP_H) |
+ // glibc, uClibc, dietlibc |
+# include <byteswap.h> |
+# ifdef HAVE_BSWAP_16 |
+# define bswap16(num) bswap_16(num) |
+# endif |
+# ifdef HAVE_BSWAP_32 |
+# define bswap32(num) bswap_32(num) |
+# endif |
+# ifdef HAVE_BSWAP_64 |
+# define bswap64(num) bswap_64(num) |
+# endif |
+ |
+#elif defined(HAVE_SYS_ENDIAN_H) |
+ // *BSDs and Darwin |
+# include <sys/endian.h> |
+ |
+#elif defined(HAVE_SYS_BYTEORDER_H) |
+ // Solaris |
+# include <sys/byteorder.h> |
+# ifdef BSWAP_16 |
+# define bswap16(num) BSWAP_16(num) |
+# endif |
+# ifdef BSWAP_32 |
+# define bswap32(num) BSWAP_32(num) |
+# endif |
+# ifdef BSWAP_64 |
+# define bswap64(num) BSWAP_64(num) |
+# endif |
+# ifdef BE_16 |
+# define conv16be(num) BE_16(num) |
+# endif |
+# ifdef BE_32 |
+# define conv32be(num) BE_32(num) |
+# endif |
+# ifdef BE_64 |
+# define conv64be(num) BE_64(num) |
+# endif |
+# ifdef LE_16 |
+# define conv16le(num) LE_16(num) |
+# endif |
+# ifdef LE_32 |
+# define conv32le(num) LE_32(num) |
+# endif |
+# ifdef LE_64 |
+# define conv64le(num) LE_64(num) |
+# endif |
+#endif |
+ |
+ |
+/////////////////// |
+// Byte swapping // |
+/////////////////// |
+ |
+#ifndef bswap16 |
+# define bswap16(num) \ |
+ (((uint16_t)(num) << 8) | ((uint16_t)(num) >> 8)) |
+#endif |
+ |
+#ifndef bswap32 |
+# define bswap32(num) \ |
+ ( (((uint32_t)(num) << 24) ) \ |
+ | (((uint32_t)(num) << 8) & UINT32_C(0x00FF0000)) \ |
+ | (((uint32_t)(num) >> 8) & UINT32_C(0x0000FF00)) \ |
+ | (((uint32_t)(num) >> 24) ) ) |
+#endif |
+ |
+#ifndef bswap64 |
+# define bswap64(num) \ |
+ ( (((uint64_t)(num) << 56) ) \ |
+ | (((uint64_t)(num) << 40) & UINT64_C(0x00FF000000000000)) \ |
+ | (((uint64_t)(num) << 24) & UINT64_C(0x0000FF0000000000)) \ |
+ | (((uint64_t)(num) << 8) & UINT64_C(0x000000FF00000000)) \ |
+ | (((uint64_t)(num) >> 8) & UINT64_C(0x00000000FF000000)) \ |
+ | (((uint64_t)(num) >> 24) & UINT64_C(0x0000000000FF0000)) \ |
+ | (((uint64_t)(num) >> 40) & UINT64_C(0x000000000000FF00)) \ |
+ | (((uint64_t)(num) >> 56) ) ) |
+#endif |
+ |
+// Define conversion macros using the basic byte swapping macros. |
+#ifdef WORDS_BIGENDIAN |
+# ifndef conv16be |
+# define conv16be(num) ((uint16_t)(num)) |
+# endif |
+# ifndef conv32be |
+# define conv32be(num) ((uint32_t)(num)) |
+# endif |
+# ifndef conv64be |
+# define conv64be(num) ((uint64_t)(num)) |
+# endif |
+# ifndef conv16le |
+# define conv16le(num) bswap16(num) |
+# endif |
+# ifndef conv32le |
+# define conv32le(num) bswap32(num) |
+# endif |
+# ifndef conv64le |
+# define conv64le(num) bswap64(num) |
+# endif |
+#else |
+# ifndef conv16be |
+# define conv16be(num) bswap16(num) |
+# endif |
+# ifndef conv32be |
+# define conv32be(num) bswap32(num) |
+# endif |
+# ifndef conv64be |
+# define conv64be(num) bswap64(num) |
+# endif |
+# ifndef conv16le |
+# define conv16le(num) ((uint16_t)(num)) |
+# endif |
+# ifndef conv32le |
+# define conv32le(num) ((uint32_t)(num)) |
+# endif |
+# ifndef conv64le |
+# define conv64le(num) ((uint64_t)(num)) |
+# endif |
+#endif |
+ |
+ |
+////////////////////////////// |
+// Aligned reads and writes // |
+////////////////////////////// |
+ |
+static inline uint16_t |
+read16be(const uint8_t *buf) |
+{ |
+ uint16_t num = *(const uint16_t *)buf; |
+ return conv16be(num); |
+} |
+ |
+ |
+static inline uint16_t |
+read16le(const uint8_t *buf) |
+{ |
+ uint16_t num = *(const uint16_t *)buf; |
+ return conv16le(num); |
+} |
+ |
+ |
+static inline uint32_t |
+read32be(const uint8_t *buf) |
+{ |
+ uint32_t num = *(const uint32_t *)buf; |
+ return conv32be(num); |
+} |
+ |
+ |
+static inline uint32_t |
+read32le(const uint8_t *buf) |
+{ |
+ uint32_t num = *(const uint32_t *)buf; |
+ return conv32le(num); |
+} |
+ |
+ |
+static inline uint64_t |
+read64be(const uint8_t *buf) |
+{ |
+ uint64_t num = *(const uint64_t *)buf; |
+ return conv64be(num); |
+} |
+ |
+ |
+static inline uint64_t |
+read64le(const uint8_t *buf) |
+{ |
+ uint64_t num = *(const uint64_t *)buf; |
+ return conv64le(num); |
+} |
+ |
+ |
+// NOTE: Possible byte swapping must be done in a macro to allow GCC |
+// to optimize byte swapping of constants when using glibc's or *BSD's |
+// byte swapping macros. The actual write is done in an inline function |
+// to make type checking of the buf pointer possible similarly to readXXYe() |
+// functions. |
+ |
+#define write16be(buf, num) write16ne((buf), conv16be(num)) |
+#define write16le(buf, num) write16ne((buf), conv16le(num)) |
+#define write32be(buf, num) write32ne((buf), conv32be(num)) |
+#define write32le(buf, num) write32ne((buf), conv32le(num)) |
+#define write64be(buf, num) write64ne((buf), conv64be(num)) |
+#define write64le(buf, num) write64ne((buf), conv64le(num)) |
+ |
+ |
+static inline void |
+write16ne(uint8_t *buf, uint16_t num) |
+{ |
+ *(uint16_t *)buf = num; |
+ return; |
+} |
+ |
+ |
+static inline void |
+write32ne(uint8_t *buf, uint32_t num) |
+{ |
+ *(uint32_t *)buf = num; |
+ return; |
+} |
+ |
+ |
+static inline void |
+write64ne(uint8_t *buf, uint64_t num) |
+{ |
+ *(uint64_t *)buf = num; |
+ return; |
+} |
+ |
+ |
+//////////////////////////////// |
+// Unaligned reads and writes // |
+//////////////////////////////// |
+ |
+// NOTE: TUKLIB_FAST_UNALIGNED_ACCESS indicates only support for 16-bit and |
+// 32-bit unaligned integer loads and stores. It's possible that 64-bit |
+// unaligned access doesn't work or is slower than byte-by-byte access. |
+// Since unaligned 64-bit is probably not needed as often as 16-bit or |
+// 32-bit, we simply don't support 64-bit unaligned access for now. |
+#ifdef TUKLIB_FAST_UNALIGNED_ACCESS |
+# define unaligned_read16be read16be |
+# define unaligned_read16le read16le |
+# define unaligned_read32be read32be |
+# define unaligned_read32le read32le |
+# define unaligned_write16be write16be |
+# define unaligned_write16le write16le |
+# define unaligned_write32be write32be |
+# define unaligned_write32le write32le |
+ |
+#else |
+ |
+static inline uint16_t |
+unaligned_read16be(const uint8_t *buf) |
+{ |
+ uint16_t num = ((uint16_t)buf[0] << 8) | (uint16_t)buf[1]; |
+ return num; |
+} |
+ |
+ |
+static inline uint16_t |
+unaligned_read16le(const uint8_t *buf) |
+{ |
+ uint16_t num = ((uint16_t)buf[0]) | ((uint16_t)buf[1] << 8); |
+ return num; |
+} |
+ |
+ |
+static inline uint32_t |
+unaligned_read32be(const uint8_t *buf) |
+{ |
+ uint32_t num = (uint32_t)buf[0] << 24; |
+ num |= (uint32_t)buf[1] << 16; |
+ num |= (uint32_t)buf[2] << 8; |
+ num |= (uint32_t)buf[3]; |
+ return num; |
+} |
+ |
+ |
+static inline uint32_t |
+unaligned_read32le(const uint8_t *buf) |
+{ |
+ uint32_t num = (uint32_t)buf[0]; |
+ num |= (uint32_t)buf[1] << 8; |
+ num |= (uint32_t)buf[2] << 16; |
+ num |= (uint32_t)buf[3] << 24; |
+ return num; |
+} |
+ |
+ |
+static inline void |
+unaligned_write16be(uint8_t *buf, uint16_t num) |
+{ |
+ buf[0] = num >> 8; |
+ buf[1] = num; |
+ return; |
+} |
+ |
+ |
+static inline void |
+unaligned_write16le(uint8_t *buf, uint16_t num) |
+{ |
+ buf[0] = num; |
+ buf[1] = num >> 8; |
+ return; |
+} |
+ |
+ |
+static inline void |
+unaligned_write32be(uint8_t *buf, uint32_t num) |
+{ |
+ buf[0] = num >> 24; |
+ buf[1] = num >> 16; |
+ buf[2] = num >> 8; |
+ buf[3] = num; |
+ return; |
+} |
+ |
+ |
+static inline void |
+unaligned_write32le(uint8_t *buf, uint32_t num) |
+{ |
+ buf[0] = num; |
+ buf[1] = num >> 8; |
+ buf[2] = num >> 16; |
+ buf[3] = num >> 24; |
+ return; |
+} |
+ |
+#endif |
+ |
+ |
+static inline uint32_t |
+bsr32(uint32_t n) |
+{ |
+ // Check for ICC first, since it tends to define __GNUC__ too. |
+#if defined(__INTEL_COMPILER) |
+ return _bit_scan_reverse(n); |
+ |
+#elif TUKLIB_GNUC_REQ(3, 4) && UINT_MAX == UINT32_MAX |
+ // GCC >= 3.4 has __builtin_clz(), which gives good results on |
+ // multiple architectures. On x86, __builtin_clz() ^ 31U becomes |
+ // either plain BSR (so the XOR gets optimized away) or LZCNT and |
+ // XOR (if -march indicates that SSE4a instructions are supported). |
+ return __builtin_clz(n) ^ 31U; |
+ |
+#elif defined(__GNUC__) && (defined(__i386__) || defined(__x86_64__)) |
+ uint32_t i; |
+ __asm__("bsrl %1, %0" : "=r" (i) : "rm" (n)); |
+ return i; |
+ |
+#elif defined(_MSC_VER) && _MSC_VER >= 1400 |
+ // MSVC isn't supported by tuklib, but since this code exists, |
+ // it doesn't hurt to have it here anyway. |
+ uint32_t i; |
+ _BitScanReverse((DWORD *)&i, n); |
+ return i; |
+ |
+#else |
+ uint32_t i = 31; |
+ |
+ if ((n & UINT32_C(0xFFFF0000)) == 0) { |
+ n <<= 16; |
+ i = 15; |
+ } |
+ |
+ if ((n & UINT32_C(0xFF000000)) == 0) { |
+ n <<= 8; |
+ i -= 8; |
+ } |
+ |
+ if ((n & UINT32_C(0xF0000000)) == 0) { |
+ n <<= 4; |
+ i -= 4; |
+ } |
+ |
+ if ((n & UINT32_C(0xC0000000)) == 0) { |
+ n <<= 2; |
+ i -= 2; |
+ } |
+ |
+ if ((n & UINT32_C(0x80000000)) == 0) |
+ --i; |
+ |
+ return i; |
+#endif |
+} |
+ |
+ |
+static inline uint32_t |
+clz32(uint32_t n) |
+{ |
+#if defined(__INTEL_COMPILER) |
+ return _bit_scan_reverse(n) ^ 31U; |
+ |
+#elif TUKLIB_GNUC_REQ(3, 4) && UINT_MAX == UINT32_MAX |
+ return __builtin_clz(n); |
+ |
+#elif defined(__GNUC__) && (defined(__i386__) || defined(__x86_64__)) |
+ uint32_t i; |
+ __asm__("bsrl %1, %0\n\t" |
+ "xorl $31, %0" |
+ : "=r" (i) : "rm" (n)); |
+ return i; |
+ |
+#elif defined(_MSC_VER) && _MSC_VER >= 1400 |
+ uint32_t i; |
+ _BitScanReverse((DWORD *)&i, n); |
+ return i ^ 31U; |
+ |
+#else |
+ uint32_t i = 0; |
+ |
+ if ((n & UINT32_C(0xFFFF0000)) == 0) { |
+ n <<= 16; |
+ i = 16; |
+ } |
+ |
+ if ((n & UINT32_C(0xFF000000)) == 0) { |
+ n <<= 8; |
+ i += 8; |
+ } |
+ |
+ if ((n & UINT32_C(0xF0000000)) == 0) { |
+ n <<= 4; |
+ i += 4; |
+ } |
+ |
+ if ((n & UINT32_C(0xC0000000)) == 0) { |
+ n <<= 2; |
+ i += 2; |
+ } |
+ |
+ if ((n & UINT32_C(0x80000000)) == 0) |
+ ++i; |
+ |
+ return i; |
+#endif |
+} |
+ |
+ |
+static inline uint32_t |
+ctz32(uint32_t n) |
+{ |
+#if defined(__INTEL_COMPILER) |
+ return _bit_scan_forward(n); |
+ |
+#elif TUKLIB_GNUC_REQ(3, 4) && UINT_MAX >= UINT32_MAX |
+ return __builtin_ctz(n); |
+ |
+#elif defined(__GNUC__) && (defined(__i386__) || defined(__x86_64__)) |
+ uint32_t i; |
+ __asm__("bsfl %1, %0" : "=r" (i) : "rm" (n)); |
+ return i; |
+ |
+#elif defined(_MSC_VER) && _MSC_VER >= 1400 |
+ uint32_t i; |
+ _BitScanForward((DWORD *)&i, n); |
+ return i; |
+ |
+#else |
+ uint32_t i = 0; |
+ |
+ if ((n & UINT32_C(0x0000FFFF)) == 0) { |
+ n >>= 16; |
+ i = 16; |
+ } |
+ |
+ if ((n & UINT32_C(0x000000FF)) == 0) { |
+ n >>= 8; |
+ i += 8; |
+ } |
+ |
+ if ((n & UINT32_C(0x0000000F)) == 0) { |
+ n >>= 4; |
+ i += 4; |
+ } |
+ |
+ if ((n & UINT32_C(0x00000003)) == 0) { |
+ n >>= 2; |
+ i += 2; |
+ } |
+ |
+ if ((n & UINT32_C(0x00000001)) == 0) |
+ ++i; |
+ |
+ return i; |
+#endif |
+} |
+ |
+#define bsf32 ctz32 |
+ |
+#endif |
Property changes on: xz/src/common/tuklib_integer.h |
___________________________________________________________________ |
Added: svn:eol-style |
+ LF |