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Diffstat (limited to 'modules/brotli/enc/write_bits.h')
-rw-r--r--modules/brotli/enc/write_bits.h52
1 files changed, 27 insertions, 25 deletions
diff --git a/modules/brotli/enc/write_bits.h b/modules/brotli/enc/write_bits.h
index 36515a6893..f6f88b45be 100644
--- a/modules/brotli/enc/write_bits.h
+++ b/modules/brotli/enc/write_bits.h
@@ -16,8 +16,6 @@
extern "C" {
#endif
-/*#define BIT_WRITER_DEBUG */
-
/* This function writes bits into bytes in increasing addresses, and within
a byte least-significant-bit first.
@@ -28,7 +26,7 @@ extern "C" {
0000 0RRR 0000 0000 0000 0000
- Now, we could write 5 or less bits in MSB by just sifting by 3
+ Now, we could write 5 or less bits in MSB by just shifting by 3
and OR'ing to BYTE-0.
For n bits, we take the last 5 bits, OR that with high bits in BYTE-0,
@@ -37,37 +35,41 @@ static BROTLI_INLINE void BrotliWriteBits(size_t n_bits,
uint64_t bits,
size_t* BROTLI_RESTRICT pos,
uint8_t* BROTLI_RESTRICT array) {
+ BROTLI_LOG(("WriteBits %2d 0x%08x%08x %10d\n", (int)n_bits,
+ (uint32_t)(bits >> 32), (uint32_t)(bits & 0xFFFFFFFF),
+ (int)*pos));
+ BROTLI_DCHECK((bits >> n_bits) == 0);
+ BROTLI_DCHECK(n_bits <= 56);
#if defined(BROTLI_LITTLE_ENDIAN)
/* This branch of the code can write up to 56 bits at a time,
7 bits are lost by being perhaps already in *p and at least
1 bit is needed to initialize the bit-stream ahead (i.e. if 7
bits are in *p and we write 57 bits, then the next write will
access a byte that was never initialized). */
- uint8_t* p = &array[*pos >> 3];
- uint64_t v = (uint64_t)(*p); /* Zero-extend 8 to 64 bits. */
- BROTLI_LOG(("WriteBits %2d 0x%08x%08x %10d\n", (int)n_bits,
- (uint32_t)(bits >> 32), (uint32_t)(bits & 0xFFFFFFFF),
- (int)*pos));
- BROTLI_DCHECK((bits >> n_bits) == 0);
- BROTLI_DCHECK(n_bits <= 56);
- v |= bits << (*pos & 7);
- BROTLI_UNALIGNED_STORE64LE(p, v); /* Set some bits. */
- *pos += n_bits;
+ {
+ uint8_t* p = &array[*pos >> 3];
+ uint64_t v = (uint64_t)(*p); /* Zero-extend 8 to 64 bits. */
+ v |= bits << (*pos & 7);
+ BROTLI_UNALIGNED_STORE64LE(p, v); /* Set some bits. */
+ *pos += n_bits;
+ }
#else
/* implicit & 0xFF is assumed for uint8_t arithmetics */
- uint8_t* array_pos = &array[*pos >> 3];
- const size_t bits_reserved_in_first_byte = (*pos & 7);
- size_t bits_left_to_write;
- bits <<= bits_reserved_in_first_byte;
- *array_pos++ |= (uint8_t)bits;
- for (bits_left_to_write = n_bits + bits_reserved_in_first_byte;
- bits_left_to_write >= 9;
- bits_left_to_write -= 8) {
- bits >>= 8;
- *array_pos++ = (uint8_t)bits;
+ {
+ uint8_t* array_pos = &array[*pos >> 3];
+ const size_t bits_reserved_in_first_byte = (*pos & 7);
+ size_t bits_left_to_write;
+ bits <<= bits_reserved_in_first_byte;
+ *array_pos++ |= (uint8_t)bits;
+ for (bits_left_to_write = n_bits + bits_reserved_in_first_byte;
+ bits_left_to_write >= 9;
+ bits_left_to_write -= 8) {
+ bits >>= 8;
+ *array_pos++ = (uint8_t)bits;
+ }
+ *array_pos = 0;
+ *pos += n_bits;
}
- *array_pos = 0;
- *pos += n_bits;
#endif
}