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diff --git a/media/libwebp/utils/bit_reader_inl_utils.h b/media/libwebp/utils/bit_reader_inl_utils.h
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+// 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_