qemu/include/qemu/bswap.h
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   1#ifndef BSWAP_H
   2#define BSWAP_H
   3
   4#include "fpu/softfloat-types.h"
   5
   6#ifdef CONFIG_MACHINE_BSWAP_H
   7# include <sys/endian.h>
   8# include <machine/bswap.h>
   9#elif defined(__FreeBSD__)
  10# include <sys/endian.h>
  11#elif defined(CONFIG_BYTESWAP_H)
  12# include <byteswap.h>
  13
  14static inline uint16_t bswap16(uint16_t x)
  15{
  16    return bswap_16(x);
  17}
  18
  19static inline uint32_t bswap32(uint32_t x)
  20{
  21    return bswap_32(x);
  22}
  23
  24static inline uint64_t bswap64(uint64_t x)
  25{
  26    return bswap_64(x);
  27}
  28# else
  29static inline uint16_t bswap16(uint16_t x)
  30{
  31    return (((x & 0x00ff) << 8) |
  32            ((x & 0xff00) >> 8));
  33}
  34
  35static inline uint32_t bswap32(uint32_t x)
  36{
  37    return (((x & 0x000000ffU) << 24) |
  38            ((x & 0x0000ff00U) <<  8) |
  39            ((x & 0x00ff0000U) >>  8) |
  40            ((x & 0xff000000U) >> 24));
  41}
  42
  43static inline uint64_t bswap64(uint64_t x)
  44{
  45    return (((x & 0x00000000000000ffULL) << 56) |
  46            ((x & 0x000000000000ff00ULL) << 40) |
  47            ((x & 0x0000000000ff0000ULL) << 24) |
  48            ((x & 0x00000000ff000000ULL) <<  8) |
  49            ((x & 0x000000ff00000000ULL) >>  8) |
  50            ((x & 0x0000ff0000000000ULL) >> 24) |
  51            ((x & 0x00ff000000000000ULL) >> 40) |
  52            ((x & 0xff00000000000000ULL) >> 56));
  53}
  54#endif /* ! CONFIG_MACHINE_BSWAP_H */
  55
  56static inline void bswap16s(uint16_t *s)
  57{
  58    *s = bswap16(*s);
  59}
  60
  61static inline void bswap32s(uint32_t *s)
  62{
  63    *s = bswap32(*s);
  64}
  65
  66static inline void bswap64s(uint64_t *s)
  67{
  68    *s = bswap64(*s);
  69}
  70
  71#if defined(HOST_WORDS_BIGENDIAN)
  72#define be_bswap(v, size) (v)
  73#define le_bswap(v, size) glue(bswap, size)(v)
  74#define be_bswaps(v, size)
  75#define le_bswaps(p, size) do { *p = glue(bswap, size)(*p); } while(0)
  76#else
  77#define le_bswap(v, size) (v)
  78#define be_bswap(v, size) glue(bswap, size)(v)
  79#define le_bswaps(v, size)
  80#define be_bswaps(p, size) do { *p = glue(bswap, size)(*p); } while(0)
  81#endif
  82
  83/**
  84 * Endianness conversion functions between host cpu and specified endianness.
  85 * (We list the complete set of prototypes produced by the macros below
  86 * to assist people who search the headers to find their definitions.)
  87 *
  88 * uint16_t le16_to_cpu(uint16_t v);
  89 * uint32_t le32_to_cpu(uint32_t v);
  90 * uint64_t le64_to_cpu(uint64_t v);
  91 * uint16_t be16_to_cpu(uint16_t v);
  92 * uint32_t be32_to_cpu(uint32_t v);
  93 * uint64_t be64_to_cpu(uint64_t v);
  94 *
  95 * Convert the value @v from the specified format to the native
  96 * endianness of the host CPU by byteswapping if necessary, and
  97 * return the converted value.
  98 *
  99 * uint16_t cpu_to_le16(uint16_t v);
 100 * uint32_t cpu_to_le32(uint32_t v);
 101 * uint64_t cpu_to_le64(uint64_t v);
 102 * uint16_t cpu_to_be16(uint16_t v);
 103 * uint32_t cpu_to_be32(uint32_t v);
 104 * uint64_t cpu_to_be64(uint64_t v);
 105 *
 106 * Convert the value @v from the native endianness of the host CPU to
 107 * the specified format by byteswapping if necessary, and return
 108 * the converted value.
 109 *
 110 * void le16_to_cpus(uint16_t *v);
 111 * void le32_to_cpus(uint32_t *v);
 112 * void le64_to_cpus(uint64_t *v);
 113 * void be16_to_cpus(uint16_t *v);
 114 * void be32_to_cpus(uint32_t *v);
 115 * void be64_to_cpus(uint64_t *v);
 116 *
 117 * Do an in-place conversion of the value pointed to by @v from the
 118 * specified format to the native endianness of the host CPU.
 119 *
 120 * void cpu_to_le16s(uint16_t *v);
 121 * void cpu_to_le32s(uint32_t *v);
 122 * void cpu_to_le64s(uint64_t *v);
 123 * void cpu_to_be16s(uint16_t *v);
 124 * void cpu_to_be32s(uint32_t *v);
 125 * void cpu_to_be64s(uint64_t *v);
 126 *
 127 * Do an in-place conversion of the value pointed to by @v from the
 128 * native endianness of the host CPU to the specified format.
 129 *
 130 * Both X_to_cpu() and cpu_to_X() perform the same operation; you
 131 * should use whichever one is better documenting of the function your
 132 * code is performing.
 133 *
 134 * Do not use these functions for conversion of values which are in guest
 135 * memory, since the data may not be sufficiently aligned for the host CPU's
 136 * load and store instructions. Instead you should use the ld*_p() and
 137 * st*_p() functions, which perform loads and stores of data of any
 138 * required size and endianness and handle possible misalignment.
 139 */
 140
 141#define CPU_CONVERT(endian, size, type)\
 142static inline type endian ## size ## _to_cpu(type v)\
 143{\
 144    return glue(endian, _bswap)(v, size);\
 145}\
 146\
 147static inline type cpu_to_ ## endian ## size(type v)\
 148{\
 149    return glue(endian, _bswap)(v, size);\
 150}\
 151\
 152static inline void endian ## size ## _to_cpus(type *p)\
 153{\
 154    glue(endian, _bswaps)(p, size);\
 155}\
 156\
 157static inline void cpu_to_ ## endian ## size ## s(type *p)\
 158{\
 159    glue(endian, _bswaps)(p, size);\
 160}
 161
 162CPU_CONVERT(be, 16, uint16_t)
 163CPU_CONVERT(be, 32, uint32_t)
 164CPU_CONVERT(be, 64, uint64_t)
 165
 166CPU_CONVERT(le, 16, uint16_t)
 167CPU_CONVERT(le, 32, uint32_t)
 168CPU_CONVERT(le, 64, uint64_t)
 169
 170/* len must be one of 1, 2, 4 */
 171static inline uint32_t qemu_bswap_len(uint32_t value, int len)
 172{
 173    return bswap32(value) >> (32 - 8 * len);
 174}
 175
 176/*
 177 * Same as cpu_to_le{16,32}, except that gcc will figure the result is
 178 * a compile-time constant if you pass in a constant.  So this can be
 179 * used to initialize static variables.
 180 */
 181#if defined(HOST_WORDS_BIGENDIAN)
 182# define const_le32(_x)                          \
 183    ((((_x) & 0x000000ffU) << 24) |              \
 184     (((_x) & 0x0000ff00U) <<  8) |              \
 185     (((_x) & 0x00ff0000U) >>  8) |              \
 186     (((_x) & 0xff000000U) >> 24))
 187# define const_le16(_x)                          \
 188    ((((_x) & 0x00ff) << 8) |                    \
 189     (((_x) & 0xff00) >> 8))
 190#else
 191# define const_le32(_x) (_x)
 192# define const_le16(_x) (_x)
 193#endif
 194
 195/* Unions for reinterpreting between floats and integers.  */
 196
 197typedef union {
 198    float32 f;
 199    uint32_t l;
 200} CPU_FloatU;
 201
 202typedef union {
 203    float64 d;
 204#if defined(HOST_WORDS_BIGENDIAN)
 205    struct {
 206        uint32_t upper;
 207        uint32_t lower;
 208    } l;
 209#else
 210    struct {
 211        uint32_t lower;
 212        uint32_t upper;
 213    } l;
 214#endif
 215    uint64_t ll;
 216} CPU_DoubleU;
 217
 218typedef union {
 219     floatx80 d;
 220     struct {
 221         uint64_t lower;
 222         uint16_t upper;
 223     } l;
 224} CPU_LDoubleU;
 225
 226typedef union {
 227    float128 q;
 228#if defined(HOST_WORDS_BIGENDIAN)
 229    struct {
 230        uint32_t upmost;
 231        uint32_t upper;
 232        uint32_t lower;
 233        uint32_t lowest;
 234    } l;
 235    struct {
 236        uint64_t upper;
 237        uint64_t lower;
 238    } ll;
 239#else
 240    struct {
 241        uint32_t lowest;
 242        uint32_t lower;
 243        uint32_t upper;
 244        uint32_t upmost;
 245    } l;
 246    struct {
 247        uint64_t lower;
 248        uint64_t upper;
 249    } ll;
 250#endif
 251} CPU_QuadU;
 252
 253/* unaligned/endian-independent pointer access */
 254
 255/*
 256 * the generic syntax is:
 257 *
 258 * load: ld{type}{sign}{size}_{endian}_p(ptr)
 259 *
 260 * store: st{type}{size}_{endian}_p(ptr, val)
 261 *
 262 * Note there are small differences with the softmmu access API!
 263 *
 264 * type is:
 265 * (empty): integer access
 266 *   f    : float access
 267 *
 268 * sign is:
 269 * (empty): for 32 or 64 bit sizes (including floats and doubles)
 270 *   u    : unsigned
 271 *   s    : signed
 272 *
 273 * size is:
 274 *   b: 8 bits
 275 *   w: 16 bits
 276 *   l: 32 bits
 277 *   q: 64 bits
 278 *
 279 * endian is:
 280 *   he   : host endian
 281 *   be   : big endian
 282 *   le   : little endian
 283 *   te   : target endian
 284 * (except for byte accesses, which have no endian infix).
 285 *
 286 * The target endian accessors are obviously only available to source
 287 * files which are built per-target; they are defined in cpu-all.h.
 288 *
 289 * In all cases these functions take a host pointer.
 290 * For accessors that take a guest address rather than a
 291 * host address, see the cpu_{ld,st}_* accessors defined in
 292 * cpu_ldst.h.
 293 *
 294 * For cases where the size to be used is not fixed at compile time,
 295 * there are
 296 *  stn_{endian}_p(ptr, sz, val)
 297 * which stores @val to @ptr as an @endian-order number @sz bytes in size
 298 * and
 299 *  ldn_{endian}_p(ptr, sz)
 300 * which loads @sz bytes from @ptr as an unsigned @endian-order number
 301 * and returns it in a uint64_t.
 302 */
 303
 304static inline int ldub_p(const void *ptr)
 305{
 306    return *(uint8_t *)ptr;
 307}
 308
 309static inline int ldsb_p(const void *ptr)
 310{
 311    return *(int8_t *)ptr;
 312}
 313
 314static inline void stb_p(void *ptr, uint8_t v)
 315{
 316    *(uint8_t *)ptr = v;
 317}
 318
 319/*
 320 * Any compiler worth its salt will turn these memcpy into native unaligned
 321 * operations.  Thus we don't need to play games with packed attributes, or
 322 * inline byte-by-byte stores.
 323 * Some compilation environments (eg some fortify-source implementations)
 324 * may intercept memcpy() in a way that defeats the compiler optimization,
 325 * though, so we use __builtin_memcpy() to give ourselves the best chance
 326 * of good performance.
 327 */
 328
 329static inline int lduw_he_p(const void *ptr)
 330{
 331    uint16_t r;
 332    __builtin_memcpy(&r, ptr, sizeof(r));
 333    return r;
 334}
 335
 336static inline int ldsw_he_p(const void *ptr)
 337{
 338    int16_t r;
 339    __builtin_memcpy(&r, ptr, sizeof(r));
 340    return r;
 341}
 342
 343static inline void stw_he_p(void *ptr, uint16_t v)
 344{
 345    __builtin_memcpy(ptr, &v, sizeof(v));
 346}
 347
 348static inline int ldl_he_p(const void *ptr)
 349{
 350    int32_t r;
 351    __builtin_memcpy(&r, ptr, sizeof(r));
 352    return r;
 353}
 354
 355static inline void stl_he_p(void *ptr, uint32_t v)
 356{
 357    __builtin_memcpy(ptr, &v, sizeof(v));
 358}
 359
 360static inline uint64_t ldq_he_p(const void *ptr)
 361{
 362    uint64_t r;
 363    __builtin_memcpy(&r, ptr, sizeof(r));
 364    return r;
 365}
 366
 367static inline void stq_he_p(void *ptr, uint64_t v)
 368{
 369    __builtin_memcpy(ptr, &v, sizeof(v));
 370}
 371
 372static inline int lduw_le_p(const void *ptr)
 373{
 374    return (uint16_t)le_bswap(lduw_he_p(ptr), 16);
 375}
 376
 377static inline int ldsw_le_p(const void *ptr)
 378{
 379    return (int16_t)le_bswap(lduw_he_p(ptr), 16);
 380}
 381
 382static inline int ldl_le_p(const void *ptr)
 383{
 384    return le_bswap(ldl_he_p(ptr), 32);
 385}
 386
 387static inline uint64_t ldq_le_p(const void *ptr)
 388{
 389    return le_bswap(ldq_he_p(ptr), 64);
 390}
 391
 392static inline void stw_le_p(void *ptr, uint16_t v)
 393{
 394    stw_he_p(ptr, le_bswap(v, 16));
 395}
 396
 397static inline void stl_le_p(void *ptr, uint32_t v)
 398{
 399    stl_he_p(ptr, le_bswap(v, 32));
 400}
 401
 402static inline void stq_le_p(void *ptr, uint64_t v)
 403{
 404    stq_he_p(ptr, le_bswap(v, 64));
 405}
 406
 407/* float access */
 408
 409static inline float32 ldfl_le_p(const void *ptr)
 410{
 411    CPU_FloatU u;
 412    u.l = ldl_le_p(ptr);
 413    return u.f;
 414}
 415
 416static inline void stfl_le_p(void *ptr, float32 v)
 417{
 418    CPU_FloatU u;
 419    u.f = v;
 420    stl_le_p(ptr, u.l);
 421}
 422
 423static inline float64 ldfq_le_p(const void *ptr)
 424{
 425    CPU_DoubleU u;
 426    u.ll = ldq_le_p(ptr);
 427    return u.d;
 428}
 429
 430static inline void stfq_le_p(void *ptr, float64 v)
 431{
 432    CPU_DoubleU u;
 433    u.d = v;
 434    stq_le_p(ptr, u.ll);
 435}
 436
 437static inline int lduw_be_p(const void *ptr)
 438{
 439    return (uint16_t)be_bswap(lduw_he_p(ptr), 16);
 440}
 441
 442static inline int ldsw_be_p(const void *ptr)
 443{
 444    return (int16_t)be_bswap(lduw_he_p(ptr), 16);
 445}
 446
 447static inline int ldl_be_p(const void *ptr)
 448{
 449    return be_bswap(ldl_he_p(ptr), 32);
 450}
 451
 452static inline uint64_t ldq_be_p(const void *ptr)
 453{
 454    return be_bswap(ldq_he_p(ptr), 64);
 455}
 456
 457static inline void stw_be_p(void *ptr, uint16_t v)
 458{
 459    stw_he_p(ptr, be_bswap(v, 16));
 460}
 461
 462static inline void stl_be_p(void *ptr, uint32_t v)
 463{
 464    stl_he_p(ptr, be_bswap(v, 32));
 465}
 466
 467static inline void stq_be_p(void *ptr, uint64_t v)
 468{
 469    stq_he_p(ptr, be_bswap(v, 64));
 470}
 471
 472/* float access */
 473
 474static inline float32 ldfl_be_p(const void *ptr)
 475{
 476    CPU_FloatU u;
 477    u.l = ldl_be_p(ptr);
 478    return u.f;
 479}
 480
 481static inline void stfl_be_p(void *ptr, float32 v)
 482{
 483    CPU_FloatU u;
 484    u.f = v;
 485    stl_be_p(ptr, u.l);
 486}
 487
 488static inline float64 ldfq_be_p(const void *ptr)
 489{
 490    CPU_DoubleU u;
 491    u.ll = ldq_be_p(ptr);
 492    return u.d;
 493}
 494
 495static inline void stfq_be_p(void *ptr, float64 v)
 496{
 497    CPU_DoubleU u;
 498    u.d = v;
 499    stq_be_p(ptr, u.ll);
 500}
 501
 502static inline unsigned long leul_to_cpu(unsigned long v)
 503{
 504#if HOST_LONG_BITS == 32
 505    return le_bswap(v, 32);
 506#elif HOST_LONG_BITS == 64
 507    return le_bswap(v, 64);
 508#else
 509# error Unknown sizeof long
 510#endif
 511}
 512
 513/* Store v to p as a sz byte value in host order */
 514#define DO_STN_LDN_P(END) \
 515    static inline void stn_## END ## _p(void *ptr, int sz, uint64_t v)  \
 516    {                                                                   \
 517        switch (sz) {                                                   \
 518        case 1:                                                         \
 519            stb_p(ptr, v);                                              \
 520            break;                                                      \
 521        case 2:                                                         \
 522            stw_ ## END ## _p(ptr, v);                                  \
 523            break;                                                      \
 524        case 4:                                                         \
 525            stl_ ## END ## _p(ptr, v);                                  \
 526            break;                                                      \
 527        case 8:                                                         \
 528            stq_ ## END ## _p(ptr, v);                                  \
 529            break;                                                      \
 530        default:                                                        \
 531            g_assert_not_reached();                                     \
 532        }                                                               \
 533    }                                                                   \
 534    static inline uint64_t ldn_## END ## _p(const void *ptr, int sz)    \
 535    {                                                                   \
 536        switch (sz) {                                                   \
 537        case 1:                                                         \
 538            return ldub_p(ptr);                                         \
 539        case 2:                                                         \
 540            return lduw_ ## END ## _p(ptr);                             \
 541        case 4:                                                         \
 542            return (uint32_t)ldl_ ## END ## _p(ptr);                    \
 543        case 8:                                                         \
 544            return ldq_ ## END ## _p(ptr);                              \
 545        default:                                                        \
 546            g_assert_not_reached();                                     \
 547        }                                                               \
 548    }
 549
 550DO_STN_LDN_P(he)
 551DO_STN_LDN_P(le)
 552DO_STN_LDN_P(be)
 553
 554#undef DO_STN_LDN_P
 555
 556#undef le_bswap
 557#undef be_bswap
 558#undef le_bswaps
 559#undef be_bswaps
 560
 561#endif /* BSWAP_H */
 562