Commit 7db2145a authored by Richard Henderson's avatar Richard Henderson Committed by Blue Swirl
Browse files

bswap: Add host endian unaligned access functions 



Signed-off-by: default avatarRichard Henderson <rth@twiddle.net>
Signed-off-by: default avatarBlue Swirl <blauwirbel@gmail.com>
parent cdfe2851

include/qemu/bswap.h

+50 −1
Original line number Diff line number Diff line
@@ -226,6 +226,8 @@ static inline uint32_t qemu_bswap_len(uint32_t value, int len) 
    return bswap32(value) >> (32 - 8 * len);

}



/* Unions for reinterpreting between floats and integers.  */



typedef union {

    float32 f;

    uint32_t l;
@@ -309,7 +311,7 @@ typedef union { 
 *   q: 64 bits

 *

 * endian is:

 * (empty): 8 bit access

 * (empty): host endian

 *   be   : big endian

 *   le   : little endian

 */
@@ -328,6 +330,53 @@ static inline void stb_p(void *ptr, int v) 
    *(uint8_t *)ptr = v;

}



/* Any compiler worth its salt will turn these memcpy into native unaligned

   operations.  Thus we don't need to play games with packed attributes, or

   inline byte-by-byte stores.  */



static inline int lduw_p(const void *ptr)

{

    uint16_t r;

    memcpy(&r, ptr, sizeof(r));

    return r;

}



static inline int ldsw_p(const void *ptr)

{

    int16_t r;

    memcpy(&r, ptr, sizeof(r));

    return r;

}



static inline void stw_p(void *ptr, uint16_t v)

{

    memcpy(ptr, &v, sizeof(v));

}



static inline int ldl_p(const void *ptr)

{

    int32_t r;

    memcpy(&r, ptr, sizeof(r));

    return r;

}



static inline void stl_p(void *ptr, uint32_t v)

{

    memcpy(ptr, &v, sizeof(v));

}



static inline uint64_t ldq_p(const void *ptr)

{

    uint64_t r;

    memcpy(&r, ptr, sizeof(r));

    return r;

}



static inline void stq_p(void *ptr, uint64_t v)

{

    memcpy(ptr, &v, sizeof(v));

}



/* NOTE: on arm, putting 2 in /proc/sys/debug/alignment so that the

   kernel handles unaligned load/stores may give better results, but

   it is a system wide setting : bad */