bit_reader_inl_utils.h | Explore in Territory

// Copyright 2014 Google Inc. All Rights Reserved.
//
// Use of this source code is governed by a BSD-style license
// that can be found in the COPYING 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.
// -----------------------------------------------------------------------------
//
// Specific inlined methods for boolean decoder [VP8GetBit() ...]
// This file should be included by the .c sources that actually need to call
// these methods.
//
// Author: Skal ([email protected])

#ifndef WEBP_UTILS_BIT_READER_INL_UTILS_H_
#define WEBP_UTILS_BIT_READER_INL_UTILS_H_

#ifdef HAVE_CONFIG_H
#include "src/webp/config.h"
#endif

#include <string.h>  // for memcpy

#include "src/dsp/dsp.h"
#include "src/utils/bit_reader_utils.h"
#include "src/utils/endian_inl_utils.h"
#include "src/utils/utils.h"

#ifdef __cplusplus
extern "C" {
#endif

//------------------------------------------------------------------------------
// Derived type lbit_t = natural type for memory I/O

#if   (BITS > 32)
lbit_t;
#elif (BITS > 16)
typedef uint32_t lbit_t;
#elif (BITS >  8)
typedef uint16_t lbit_t;
#else
typedef uint8_t lbit_t;
#endif

extern const uint8_t kVP8Log2Range[128];
extern const uint8_t kVP8NewRange[128];

// special case for the tail byte-reading
void VP8LoadFinalBytes(VP8BitReader* const br);

//------------------------------------------------------------------------------
// Inlined critical functions

// makes sure br->value_ has at least BITS bits worth of data
static WEBP_UBSAN_IGNORE_UNDEF WEBP_INLINE
void VP8LoadNewBytes(VP8BitReader* WEBP_RESTRICT const br) { … }

// Read a bit with proba 'prob'. Speed-critical function!
static WEBP_INLINE int VP8GetBit(VP8BitReader* WEBP_RESTRICT const br,
                                 int prob, const char label[]) { … }

// simplified version of VP8GetBit() for prob=0x80 (note shift is always 1 here)
static WEBP_UBSAN_IGNORE_UNSIGNED_OVERFLOW WEBP_INLINE
int VP8GetSigned(VP8BitReader* WEBP_RESTRICT const br, int v,
                 const char label[]) { … }

static WEBP_INLINE int VP8GetBitAlt(VP8BitReader* WEBP_RESTRICT const br,
                                    int prob, const char label[]) { … }

#ifdef __cplusplus
}    // extern "C"
#endif

#endif  // WEBP_UTILS_BIT_READER_INL_UTILS_H_
godot/thirdparty/libwebp/src/utils/bit_reader_inl_utils.h
