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-rw-r--r--source/util/bit_stream.h88
1 files changed, 36 insertions, 52 deletions
diff --git a/source/util/bit_stream.h b/source/util/bit_stream.h
index f98b74bf..247ae354 100644
--- a/source/util/bit_stream.h
+++ b/source/util/bit_stream.h
@@ -21,8 +21,8 @@
#include <bitset>
#include <cstdint>
#include <functional>
-#include <string>
#include <sstream>
+#include <string>
#include <vector>
namespace spvutils {
@@ -60,9 +60,7 @@ inline T GetLowerBits(T in, size_t num_bits) {
// 2 -> 4
// Motivation: -1 is 0xFF...FF what doesn't work very well with
// WriteVariableWidth which prefers to have as many 0 bits as possible.
-inline uint64_t EncodeZigZag(int64_t val) {
- return (val << 1) ^ (val >> 63);
-}
+inline uint64_t EncodeZigZag(int64_t val) { return (val << 1) ^ (val >> 63); }
// Decodes signed integer encoded with EncodeZigZag.
inline int64_t DecodeZigZag(uint64_t val) {
@@ -92,7 +90,8 @@ inline int64_t DecodeZigZag(uint64_t val) {
inline uint64_t EncodeZigZag(int64_t val, size_t block_exponent) {
assert(block_exponent < 64);
const uint64_t uval = static_cast<uint64_t>(val >= 0 ? val : -val - 1);
- const uint64_t block_num = ((uval >> block_exponent) << 1) + (val >= 0 ? 0 : 1);
+ const uint64_t block_num =
+ ((uval >> block_exponent) << 1) + (val >= 0 ? 0 : 1);
const uint64_t pos = GetLowerBits(uval, block_exponent);
return (block_num << block_exponent) + pos;
}
@@ -139,13 +138,13 @@ std::vector<T> StreamToBuffer(std::string str) {
std::vector<T> buffer;
buffer.reserve(NumBitsToNumWords<sizeof(T)>(str.length()));
for (int index = str_length - word_size; index >= 0; index -= word_size) {
- buffer.push_back(static_cast<T>(std::bitset<sizeof(T) * 8>(
- str, index, word_size).to_ullong()));
+ buffer.push_back(static_cast<T>(
+ std::bitset<sizeof(T) * 8>(str, index, word_size).to_ullong()));
}
const size_t suffix_length = str.length() % word_size;
if (suffix_length != 0) {
- buffer.push_back(static_cast<T>(std::bitset<sizeof(T) * 8>(
- str, 0, suffix_length).to_ullong()));
+ buffer.push_back(static_cast<T>(
+ std::bitset<sizeof(T) * 8>(str, 0, suffix_length).to_ullong()));
}
return buffer;
}
@@ -154,8 +153,7 @@ std::vector<T> StreamToBuffer(std::string str) {
template <size_t N>
inline std::string PadToWord(std::string&& str) {
const size_t tail_length = str.size() % N;
- if (tail_length != 0)
- str += std::string(N - tail_length, '0');
+ if (tail_length != 0) str += std::string(N - tail_length, '0');
return str;
}
@@ -174,7 +172,8 @@ inline std::bitset<N> StreamToBitset(std::string str) {
// Converts first |num_bits| of std::bitset to a left-to-right stream of bits.
template <size_t N>
-inline std::string BitsetToStream(const std::bitset<N>& bits, size_t num_bits = N) {
+inline std::string BitsetToStream(const std::bitset<N>& bits,
+ size_t num_bits = N) {
std::string str = bits.to_string().substr(N - num_bits);
std::reverse(str.begin(), str.end());
return str;
@@ -237,14 +236,14 @@ class BitWriterInterface {
void WriteVariableWidthU32(uint32_t val, size_t chunk_length);
void WriteVariableWidthU16(uint16_t val, size_t chunk_length);
void WriteVariableWidthU8(uint8_t val, size_t chunk_length);
- void WriteVariableWidthS64(
- int64_t val, size_t chunk_length, size_t zigzag_exponent);
- void WriteVariableWidthS32(
- int32_t val, size_t chunk_length, size_t zigzag_exponent);
- void WriteVariableWidthS16(
- int16_t val, size_t chunk_length, size_t zigzag_exponent);
- void WriteVariableWidthS8(
- int8_t val, size_t chunk_length, size_t zigzag_exponent);
+ void WriteVariableWidthS64(int64_t val, size_t chunk_length,
+ size_t zigzag_exponent);
+ void WriteVariableWidthS32(int32_t val, size_t chunk_length,
+ size_t zigzag_exponent);
+ void WriteVariableWidthS16(int16_t val, size_t chunk_length,
+ size_t zigzag_exponent);
+ void WriteVariableWidthS8(int8_t val, size_t chunk_length,
+ size_t zigzag_exponent);
// Writes |val| using fixed bit width. Bit width is determined by |max_val|:
// max_val 0 -> bit width 1
@@ -262,14 +261,10 @@ class BitWriterInterface {
virtual size_t GetNumBits() const = 0;
// Provides direct access to the buffer data if implemented.
- virtual const uint8_t* GetData() const {
- return nullptr;
- }
+ virtual const uint8_t* GetData() const { return nullptr; }
// Returns buffer size in bytes.
- size_t GetDataSizeBytes() const {
- return NumBitsToNumWords<8>(GetNumBits());
- }
+ size_t GetDataSizeBytes() const { return NumBitsToNumWords<8>(GetNumBits()); }
// Generates and returns byte array containing written bits.
virtual std::vector<uint8_t> GetDataCopy() const = 0;
@@ -286,9 +281,7 @@ class BitWriterWord64 : public BitWriterInterface {
void WriteBits(uint64_t bits, size_t num_bits) override;
- size_t GetNumBits() const override {
- return end_;
- }
+ size_t GetNumBits() const override { return end_; }
const uint8_t* GetData() const override {
return reinterpret_cast<const uint8_t*>(buffer_.data());
@@ -300,9 +293,7 @@ class BitWriterWord64 : public BitWriterInterface {
// Returns written stream as std::string, padded with zeroes so that the
// length is a multiple of 64.
- std::string GetStreamPadded64() const {
- return BufferToStream(buffer_);
- }
+ std::string GetStreamPadded64() const { return BufferToStream(buffer_); }
// Sets callback to emit bit sequences after every write.
void SetCallback(std::function<void(const std::string&)> callback) {
@@ -312,8 +303,7 @@ class BitWriterWord64 : public BitWriterInterface {
protected:
// Sends string generated from arguments to callback_ if defined.
void EmitSequence(uint64_t bits, size_t num_bits) const {
- if (callback_)
- callback_(BitsToStream(bits, num_bits));
+ if (callback_) callback_(BitsToStream(bits, num_bits));
}
private:
@@ -363,8 +353,7 @@ class BitReaderInterface {
static_assert(sizeof(T) <= 64, "Type size too large");
uint64_t bits = 0;
const size_t num_read = ReadBits(&bits, sizeof(T) * 8);
- if (num_read != sizeof(T) * 8)
- return false;
+ if (num_read != sizeof(T) * 8) return false;
memcpy(val, &bits, sizeof(T));
return true;
}
@@ -384,9 +373,7 @@ class BitReaderInterface {
// the buffer stream ends with padding zeroes, and would accept this as a
// 'soft' EOF. Implementations of this class do not necessarily need to
// implement this, default behavior can simply delegate to ReachedEnd().
- virtual bool OnlyZeroesLeft() const {
- return ReachedEnd();
- }
+ virtual bool OnlyZeroesLeft() const { return ReachedEnd(); }
// Reads value encoded with WriteVariableWidthXXX (see BitWriterInterface).
// Reader and writer must use the same |chunk_length| and variable type.
@@ -395,14 +382,14 @@ class BitReaderInterface {
bool ReadVariableWidthU32(uint32_t* val, size_t chunk_length);
bool ReadVariableWidthU16(uint16_t* val, size_t chunk_length);
bool ReadVariableWidthU8(uint8_t* val, size_t chunk_length);
- bool ReadVariableWidthS64(
- int64_t* val, size_t chunk_length, size_t zigzag_exponent);
- bool ReadVariableWidthS32(
- int32_t* val, size_t chunk_length, size_t zigzag_exponent);
- bool ReadVariableWidthS16(
- int16_t* val, size_t chunk_length, size_t zigzag_exponent);
- bool ReadVariableWidthS8(
- int8_t* val, size_t chunk_length, size_t zigzag_exponent);
+ bool ReadVariableWidthS64(int64_t* val, size_t chunk_length,
+ size_t zigzag_exponent);
+ bool ReadVariableWidthS32(int32_t* val, size_t chunk_length,
+ size_t zigzag_exponent);
+ bool ReadVariableWidthS16(int16_t* val, size_t chunk_length,
+ size_t zigzag_exponent);
+ bool ReadVariableWidthS8(int8_t* val, size_t chunk_length,
+ size_t zigzag_exponent);
// Reads value written by WriteFixedWidth (|max_val| needs to be the same).
// Returns true on success, false if the bit stream ends prematurely.
@@ -428,9 +415,7 @@ class BitReaderWord64 : public BitReaderInterface {
size_t ReadBits(uint64_t* bits, size_t num_bits) override;
- size_t GetNumReadBits() const override {
- return pos_;
- }
+ size_t GetNumReadBits() const override { return pos_; }
bool ReachedEnd() const override;
bool OnlyZeroesLeft() const override;
@@ -445,8 +430,7 @@ class BitReaderWord64 : public BitReaderInterface {
protected:
// Sends string generated from arguments to callback_ if defined.
void EmitSequence(uint64_t bits, size_t num_bits) const {
- if (callback_)
- callback_(BitsToStream(bits, num_bits));
+ if (callback_) callback_(BitsToStream(bits, num_bits));
}
private:
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-27 12:30:17 +0000