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/*
 *  Copyright (c) 2010 The WebM project authors. All Rights Reserved.
 *
 *  Use of this source code is governed by a BSD-style license
 *  that can be found in the LICENSE file in the root of the source
 *  tree. An additional intellectual property rights grant can be found
 *  in the file PATENTS.  All contributing project authors may
 *  be found in the AUTHORS file in the root of the source tree.
 */


/* \file mem_ops_aligned.h
 * \brief Provides portable memory access primatives for operating on aligned
 *        data
 *
 * This file is split from mem_ops.h for easier maintainence. See mem_ops.h
 * for a more detailed description of these primatives.
 */
#ifndef INCLUDED_BY_MEM_OPS_H
#error Include mem_ops.h, not mem_ops_aligned.h directly.
#endif

/* Architectures that provide instructions for doing this byte swapping
 * could redefine these macros.
 */
#define swap_endian_16(val,raw) do {\
        val = ((raw>>8) & 0x00ff) \
              | ((raw<<8) & 0xff00);\
    } while(0)
#define swap_endian_32(val,raw) do {\
        val = ((raw>>24) & 0x000000ff) \
              | ((raw>>8)  & 0x0000ff00) \
              | ((raw<<8)  & 0x00ff0000) \
              | ((raw<<24) & 0xff000000); \
    } while(0)
#define swap_endian_16_se(val,raw) do {\
        swap_endian_16(val,raw);\
        val = ((val << 16) >> 16);\
    } while(0)
#define swap_endian_32_se(val,raw) swap_endian_32(val,raw)

#define mem_get_ne_aligned_generic(end,sz) \
    static unsigned MEM_VALUE_T mem_get_##end##sz##_aligned(const void *vmem) {\
        const uint##sz##_t *mem = (const uint##sz##_t *)vmem;\
        return *mem;\
    }

#define mem_get_sne_aligned_generic(end,sz) \
    static signed MEM_VALUE_T mem_get_s##end##sz##_aligned(const void *vmem) {\
        const int##sz##_t *mem = (const int##sz##_t *)vmem;\
        return *mem;\
    }

#define mem_get_se_aligned_generic(end,sz) \
    static unsigned MEM_VALUE_T mem_get_##end##sz##_aligned(const void *vmem) {\
        const uint##sz##_t *mem = (const uint##sz##_t *)vmem;\
        unsigned MEM_VALUE_T val, raw = *mem;\
        swap_endian_##sz(val,raw);\
        return val;\
    }

#define mem_get_sse_aligned_generic(end,sz) \
    static signed MEM_VALUE_T mem_get_s##end##sz##_aligned(const void *vmem) {\
        const int##sz##_t *mem = (const int##sz##_t *)vmem;\
        unsigned MEM_VALUE_T val, raw = *mem;\
        swap_endian_##sz##_se(val,raw);\
        return val;\
    }

#define mem_put_ne_aligned_generic(end,sz) \
    static void mem_put_##end##sz##_aligned(void *vmem, MEM_VALUE_T val) {\
        uint##sz##_t *mem = (uint##sz##_t *)vmem;\
        *mem = (uint##sz##_t)val;\
    }

#define mem_put_se_aligned_generic(end,sz) \
    static void mem_put_##end##sz##_aligned(void *vmem, MEM_VALUE_T val) {\
        uint##sz##_t *mem = (uint##sz##_t *)vmem, raw;\
        swap_endian_##sz(raw,val);\
        *mem = (uint##sz##_t)raw;\
    }

#include "config.h"
#if CONFIG_BIG_ENDIAN
#define mem_get_be_aligned_generic(sz)  mem_get_ne_aligned_generic(be,sz)
#define mem_get_sbe_aligned_generic(sz) mem_get_sne_aligned_generic(be,sz)
#define mem_get_le_aligned_generic(sz)  mem_get_se_aligned_generic(le,sz)
#define mem_get_sle_aligned_generic(sz) mem_get_sse_aligned_generic(le,sz)
#define mem_put_be_aligned_generic(sz)  mem_put_ne_aligned_generic(be,sz)
#define mem_put_le_aligned_generic(sz)  mem_put_se_aligned_generic(le,sz)
#else
#define mem_get_be_aligned_generic(sz)  mem_get_se_aligned_generic(be,sz)
#define mem_get_sbe_aligned_generic(sz) mem_get_sse_aligned_generic(be,sz)
#define mem_get_le_aligned_generic(sz)  mem_get_ne_aligned_generic(le,sz)
#define mem_get_sle_aligned_generic(sz) mem_get_sne_aligned_generic(le,sz)
#define mem_put_be_aligned_generic(sz)  mem_put_se_aligned_generic(be,sz)
#define mem_put_le_aligned_generic(sz)  mem_put_ne_aligned_generic(le,sz)
#endif

#undef  mem_get_be16_aligned
#define mem_get_be16_aligned mem_ops_wrap_symbol(mem_get_be16_aligned)
mem_get_be_aligned_generic(16);

#undef  mem_get_be32_aligned
#define mem_get_be32_aligned mem_ops_wrap_symbol(mem_get_be32_aligned)
mem_get_be_aligned_generic(32);

#undef  mem_get_le16_aligned
#define mem_get_le16_aligned mem_ops_wrap_symbol(mem_get_le16_aligned)
mem_get_le_aligned_generic(16);

#undef  mem_get_le32_aligned
#define mem_get_le32_aligned mem_ops_wrap_symbol(mem_get_le32_aligned)
mem_get_le_aligned_generic(32);

#undef  mem_get_sbe16_aligned
#define mem_get_sbe16_aligned mem_ops_wrap_symbol(mem_get_sbe16_aligned)
mem_get_sbe_aligned_generic(16);

#undef  mem_get_sbe32_aligned
#define mem_get_sbe32_aligned mem_ops_wrap_symbol(mem_get_sbe32_aligned)
mem_get_sbe_aligned_generic(32);

#undef  mem_get_sle16_aligned
#define mem_get_sle16_aligned mem_ops_wrap_symbol(mem_get_sle16_aligned)
mem_get_sle_aligned_generic(16);

#undef  mem_get_sle32_aligned
#define mem_get_sle32_aligned mem_ops_wrap_symbol(mem_get_sle32_aligned)
mem_get_sle_aligned_generic(32);

#undef  mem_put_be16_aligned
#define mem_put_be16_aligned mem_ops_wrap_symbol(mem_put_be16_aligned)
mem_put_be_aligned_generic(16);

#undef  mem_put_be32_aligned
#define mem_put_be32_aligned mem_ops_wrap_symbol(mem_put_be32_aligned)
mem_put_be_aligned_generic(32);

#undef  mem_put_le16_aligned
#define mem_put_le16_aligned mem_ops_wrap_symbol(mem_put_le16_aligned)
mem_put_le_aligned_generic(16);

#undef  mem_put_le32_aligned
#define mem_put_le32_aligned mem_ops_wrap_symbol(mem_put_le32_aligned)
mem_put_le_aligned_generic(32);

#undef mem_get_ne_aligned_generic
#undef mem_get_se_aligned_generic
#undef mem_get_sne_aligned_generic
#undef mem_get_sse_aligned_generic
#undef mem_put_ne_aligned_generic
#undef mem_put_se_aligned_generic
#undef swap_endian_16
#undef swap_endian_32
#undef swap_endian_16_se
#undef swap_endian_32_se