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-rw-r--r--thirdparty/libwebp/utils/bit_reader_inl_utils.h190
1 files changed, 0 insertions, 190 deletions
diff --git a/thirdparty/libwebp/utils/bit_reader_inl_utils.h b/thirdparty/libwebp/utils/bit_reader_inl_utils.h
deleted file mode 100644
index fd7fb0446c..0000000000
--- a/thirdparty/libwebp/utils/bit_reader_inl_utils.h
+++ /dev/null
@@ -1,190 +0,0 @@
-// 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 (pascal.massimino@gmail.com)
-
-#ifndef WEBP_UTILS_BIT_READER_INL_H_
-#define WEBP_UTILS_BIT_READER_INL_H_
-
-#ifdef HAVE_CONFIG_H
-#include "../webp/config.h"
-#endif
-
-#include <string.h> // for memcpy
-
-#include "../dsp/dsp.h"
-#include "./bit_reader_utils.h"
-#include "./endian_inl_utils.h"
-#include "./utils.h"
-
-#ifdef __cplusplus
-extern "C" {
-#endif
-
-//------------------------------------------------------------------------------
-// Derived type lbit_t = natural type for memory I/O
-
-#if (BITS > 32)
-typedef uint64_t 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* const br) {
- assert(br != NULL && br->buf_ != NULL);
- // Read 'BITS' bits at a time if possible.
- if (br->buf_ < br->buf_max_) {
- // convert memory type to register type (with some zero'ing!)
- bit_t bits;
-#if defined(WEBP_USE_MIPS32)
- // This is needed because of un-aligned read.
- lbit_t in_bits;
- lbit_t* p_buf_ = (lbit_t*)br->buf_;
- __asm__ volatile(
- ".set push \n\t"
- ".set at \n\t"
- ".set macro \n\t"
- "ulw %[in_bits], 0(%[p_buf_]) \n\t"
- ".set pop \n\t"
- : [in_bits]"=r"(in_bits)
- : [p_buf_]"r"(p_buf_)
- : "memory", "at"
- );
-#else
- lbit_t in_bits;
- memcpy(&in_bits, br->buf_, sizeof(in_bits));
-#endif
- br->buf_ += BITS >> 3;
-#if !defined(WORDS_BIGENDIAN)
-#if (BITS > 32)
- bits = BSwap64(in_bits);
- bits >>= 64 - BITS;
-#elif (BITS >= 24)
- bits = BSwap32(in_bits);
- bits >>= (32 - BITS);
-#elif (BITS == 16)
- bits = BSwap16(in_bits);
-#else // BITS == 8
- bits = (bit_t)in_bits;
-#endif // BITS > 32
-#else // WORDS_BIGENDIAN
- bits = (bit_t)in_bits;
- if (BITS != 8 * sizeof(bit_t)) bits >>= (8 * sizeof(bit_t) - BITS);
-#endif
- br->value_ = bits | (br->value_ << BITS);
- br->bits_ += BITS;
- } else {
- VP8LoadFinalBytes(br); // no need to be inlined
- }
-}
-
-// Read a bit with proba 'prob'. Speed-critical function!
-static WEBP_INLINE int VP8GetBit(VP8BitReader* const br, int prob) {
- // Don't move this declaration! It makes a big speed difference to store
- // 'range' *before* calling VP8LoadNewBytes(), even if this function doesn't
- // alter br->range_ value.
- range_t range = br->range_;
- if (br->bits_ < 0) {
- VP8LoadNewBytes(br);
- }
- {
- const int pos = br->bits_;
- const range_t split = (range * prob) >> 8;
- const range_t value = (range_t)(br->value_ >> pos);
- const int bit = (value > split);
- if (bit) {
- range -= split;
- br->value_ -= (bit_t)(split + 1) << pos;
- } else {
- range = split + 1;
- }
- {
- const int shift = 7 ^ BitsLog2Floor(range);
- range <<= shift;
- br->bits_ -= shift;
- }
- br->range_ = range - 1;
- return bit;
- }
-}
-
-// simplified version of VP8GetBit() for prob=0x80 (note shift is always 1 here)
-static WEBP_UBSAN_IGNORE_UNSIGNED_OVERFLOW WEBP_INLINE
-int VP8GetSigned(VP8BitReader* const br, int v) {
- if (br->bits_ < 0) {
- VP8LoadNewBytes(br);
- }
- {
- const int pos = br->bits_;
- const range_t split = br->range_ >> 1;
- const range_t value = (range_t)(br->value_ >> pos);
- const int32_t mask = (int32_t)(split - value) >> 31; // -1 or 0
- br->bits_ -= 1;
- br->range_ += mask;
- br->range_ |= 1;
- br->value_ -= (bit_t)((split + 1) & mask) << pos;
- return (v ^ mask) - mask;
- }
-}
-
-static WEBP_INLINE int VP8GetBitAlt(VP8BitReader* const br, int prob) {
- // Don't move this declaration! It makes a big speed difference to store
- // 'range' *before* calling VP8LoadNewBytes(), even if this function doesn't
- // alter br->range_ value.
- range_t range = br->range_;
- if (br->bits_ < 0) {
- VP8LoadNewBytes(br);
- }
- {
- const int pos = br->bits_;
- const range_t split = (range * prob) >> 8;
- const range_t value = (range_t)(br->value_ >> pos);
- int bit; // Don't use 'const int bit = (value > split);", it's slower.
- if (value > split) {
- range -= split + 1;
- br->value_ -= (bit_t)(split + 1) << pos;
- bit = 1;
- } else {
- range = split;
- bit = 0;
- }
- if (range <= (range_t)0x7e) {
- const int shift = kVP8Log2Range[range];
- range = kVP8NewRange[range];
- br->bits_ -= shift;
- }
- br->range_ = range;
- return bit;
- }
-}
-
-#ifdef __cplusplus
-} // extern "C"
-#endif
-
-#endif // WEBP_UTILS_BIT_READER_INL_H_
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