| /************************************************************************** |
| * |
| * Copyright 2011 Christian König. |
| * All Rights Reserved. |
| * |
| * Permission is hereby granted, free of charge, to any person obtaining a |
| * copy of this software and associated documentation files (the |
| * "Software"), to deal in the Software without restriction, including |
| * without limitation the rights to use, copy, modify, merge, publish, |
| * distribute, sub license, and/or sell copies of the Software, and to |
| * permit persons to whom the Software is furnished to do so, subject to |
| * the following conditions: |
| * |
| * The above copyright notice and this permission notice (including the |
| * next paragraph) shall be included in all copies or substantial portions |
| * of the Software. |
| * |
| * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS |
| * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF |
| * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. |
| * IN NO EVENT SHALL TUNGSTEN GRAPHICS AND/OR ITS SUPPLIERS BE LIABLE FOR |
| * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, |
| * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE |
| * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. |
| * |
| **************************************************************************/ |
| |
| #ifndef vl_vlc_h |
| #define vl_vlc_h |
| |
| #include <assert.h> |
| |
| #include <pipe/p_compiler.h> |
| |
| #include <util/u_math.h> |
| #include "util/u_pointer.h" |
| |
| struct vl_vlc |
| { |
| uint64_t buffer; |
| unsigned valid_bits; |
| uint32_t *data; |
| uint32_t *end; |
| }; |
| |
| struct vl_vlc_entry |
| { |
| int8_t length; |
| int8_t value; |
| }; |
| |
| struct vl_vlc_compressed |
| { |
| uint16_t bitcode; |
| struct vl_vlc_entry entry; |
| }; |
| |
| static INLINE void |
| vl_vlc_init_table(struct vl_vlc_entry *dst, unsigned dst_size, const struct vl_vlc_compressed *src, unsigned src_size) |
| { |
| unsigned i, bits = util_logbase2(dst_size); |
| |
| for (i=0;i<dst_size;++i) { |
| dst[i].length = 0; |
| dst[i].value = 0; |
| } |
| |
| for(; src_size > 0; --src_size, ++src) { |
| for(i=0; i<(1 << (bits - src->entry.length)); ++i) |
| dst[src->bitcode >> (16 - bits) | i] = src->entry; |
| } |
| } |
| |
| static INLINE void |
| vl_vlc_fillbits(struct vl_vlc *vlc) |
| { |
| if (vlc->valid_bits < 32) { |
| uint32_t value = *vlc->data; |
| |
| //assert(vlc->data <= vlc->end); |
| |
| #ifndef PIPE_ARCH_BIG_ENDIAN |
| value = util_bswap32(value); |
| #endif |
| |
| vlc->buffer |= (uint64_t)value << (32 - vlc->valid_bits); |
| ++vlc->data; |
| vlc->valid_bits += 32; |
| } |
| } |
| |
| static INLINE void |
| vl_vlc_init(struct vl_vlc *vlc, const uint8_t *data, unsigned len) |
| { |
| assert(vlc); |
| assert(data && len); |
| |
| vlc->buffer = 0; |
| vlc->valid_bits = 0; |
| |
| /* align the data pointer */ |
| while (pointer_to_uintptr(data) & 3) { |
| vlc->buffer |= (uint64_t)*data << (56 - vlc->valid_bits); |
| ++data; |
| --len; |
| vlc->valid_bits += 8; |
| } |
| vlc->data = (uint32_t*)data; |
| vlc->end = (uint32_t*)(data + len); |
| |
| vl_vlc_fillbits(vlc); |
| vl_vlc_fillbits(vlc); |
| } |
| |
| static INLINE unsigned |
| vl_vlc_bytes_left(struct vl_vlc *vlc) |
| { |
| return ((uint8_t*)vlc->end)-((uint8_t*)vlc->data); |
| } |
| |
| static INLINE unsigned |
| vl_vlc_peekbits(struct vl_vlc *vlc, unsigned num_bits) |
| { |
| //assert(vlc->valid_bits >= num_bits); |
| |
| return vlc->buffer >> (64 - num_bits); |
| } |
| |
| static INLINE void |
| vl_vlc_eatbits(struct vl_vlc *vlc, unsigned num_bits) |
| { |
| //assert(vlc->valid_bits > num_bits); |
| |
| vlc->buffer <<= num_bits; |
| vlc->valid_bits -= num_bits; |
| } |
| |
| static INLINE unsigned |
| vl_vlc_get_uimsbf(struct vl_vlc *vlc, unsigned num_bits) |
| { |
| unsigned value; |
| |
| //assert(vlc->valid_bits >= num_bits); |
| |
| value = vlc->buffer >> (64 - num_bits); |
| vl_vlc_eatbits(vlc, num_bits); |
| |
| return value; |
| } |
| |
| static INLINE signed |
| vl_vlc_get_simsbf(struct vl_vlc *vlc, unsigned num_bits) |
| { |
| signed value; |
| |
| //assert(vlc->valid_bits >= num_bits); |
| |
| value = ((int64_t)vlc->buffer) >> (64 - num_bits); |
| vl_vlc_eatbits(vlc, num_bits); |
| |
| return value; |
| } |
| |
| static INLINE int8_t |
| vl_vlc_get_vlclbf(struct vl_vlc *vlc, const struct vl_vlc_entry *tbl, unsigned num_bits) |
| { |
| tbl += vl_vlc_peekbits(vlc, num_bits); |
| vl_vlc_eatbits(vlc, tbl->length); |
| return tbl->value; |
| } |
| |
| #endif /* vl_vlc_h */ |