libavutil/arm/intreadwrite.h

   1 /*
   2  * This file is part of FFmpeg.
   3  *
   4  * FFmpeg is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU Lesser General Public
   6  * License as published by the Free Software Foundation; either
   7  * version 2.1 of the License, or (at your option) any later version.
   8  *
   9  * FFmpeg is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  * Lesser General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU Lesser General Public
  15  * License along with FFmpeg; if not, write to the Free Software
  16  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  17  */
  18
  19 #ifndef AVUTIL_ARM_INTREADWRITE_H
  20 #define AVUTIL_ARM_INTREADWRITE_H
  21
  22 #include <stdint.h>
  23 #include "config.h"
  24
  25 #if HAVE_FAST_UNALIGNED && HAVE_INLINE_ASM
  26
  27 #define AV_RN16 AV_RN16
  28 static inline uint16_t AV_RN16(const void *p)
  29 {
  30     uint16_t v;
  31     __asm__ ("ldrh %0, %1" : "=r"(v) : "m"(*(const uint16_t *)p));
  32     return v;
  33 }
  34
  35 #define AV_WN16 AV_WN16
  36 static inline void AV_WN16(void *p, uint16_t v)
  37 {
  38     __asm__ ("strh %1, %0" : "=m"(*(uint16_t *)p) : "r"(v));
  39 }
  40
  41 #define AV_RN32 AV_RN32
  42 static inline uint32_t AV_RN32(const void *p)
  43 {
  44     uint32_t v;
  45     __asm__ ("ldr  %0, %1" : "=r"(v) : "m"(*(const uint32_t *)p));
  46     return v;
  47 }
  48
  49 #define AV_WN32 AV_WN32
  50 static inline void AV_WN32(void *p, uint32_t v)
  51 {
  52     __asm__ ("str  %1, %0" : "=m"(*(uint32_t *)p) : "r"(v));
  53 }
  54
  55 #define AV_RN64 AV_RN64
  56 static inline uint64_t AV_RN64(const void *p)
  57 {
  58     union { uint64_t v; uint32_t hl[2]; } v;
  59     __asm__ ("ldr   %0, %2  \n\t"
  60              "ldr   %1, %3  \n\t"
  61              : "=&r"(v.hl[0]), "=r"(v.hl[1])
  62              : "m"(*(const uint32_t*)p), "m"(*((const uint32_t*)p+1)));
  63     return v.v;
  64 }
  65
  66 #define AV_WN64 AV_WN64
  67 static inline void AV_WN64(void *p, uint64_t v)
  68 {
  69     union { uint64_t v; uint32_t hl[2]; } vv = { v };
  70     __asm__ ("str  %2, %0  \n\t"
  71              "str  %3, %1  \n\t"
  72              : "=m"(*(uint32_t*)p), "=m"(*((uint32_t*)p+1))
  73              : "r"(vv.hl[0]), "r"(vv.hl[1]));
  74 }
  75
  76 #endif /* HAVE_INLINE_ASM */
  77
  78 #endif /* AVUTIL_ARM_INTREADWRITE_H */