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Moving RLE logic to inside ZSTD_compressBlock_internal and adding assert

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This commit is contained in:
bimbashrestha 2019-08-22 12:12:44 -07:00
parent 4c90d862e3
commit cba5350f88
1 changed files with 22 additions and 25 deletions
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47
lib/compress/zstd_compress.c
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@ -2264,6 +2264,16 @@ static size_t ZSTD_buildSeqStore(ZSTD_CCtx* zc, const void* src, size_t srcSize)
return ZSTDbss_compress; return ZSTDbss_compress;
} }
/* Returns true if the given block is a RLE block */
static int ZSTD_isRLE(const BYTE *ip, size_t length) {
size_t i;
if (length < 2) return 1;
for (i = 1; i < length; ++i) {
if (ip[0] != ip[i]) return 0;
}
return 1;
}
static size_t ZSTD_compressBlock_internal(ZSTD_CCtx* zc, static size_t ZSTD_compressBlock_internal(ZSTD_CCtx* zc,
void* dst, size_t dstCapacity, void* dst, size_t dstCapacity,
const void* src, size_t srcSize) const void* src, size_t srcSize)
@ -2287,8 +2297,15 @@ static size_t ZSTD_compressBlock_internal(ZSTD_CCtx* zc,
zc->entropyWorkspace, HUF_WORKSPACE_SIZE /* statically allocated in resetCCtx */, zc->entropyWorkspace, HUF_WORKSPACE_SIZE /* statically allocated in resetCCtx */,
zc->bmi2); zc->bmi2);
if (cSize < 10 && ZSTD_isRLE(src, srcSize)) {
cSize = 1;
((BYTE*)dst)[0] = ((const BYTE*)src)[0];
}
out: out:
if (!ZSTD_isError(cSize) && cSize != 0) { if (!ZSTD_isError(cSize) && cSize > 1) {
assert(!ZSTD_isRLE(src, srcSize));
/* confirm repcodes and entropy tables when emitting a compressed block */ /* confirm repcodes and entropy tables when emitting a compressed block */
ZSTD_compressedBlockState_t* const tmp = zc->blockState.prevCBlock; ZSTD_compressedBlockState_t* const tmp = zc->blockState.prevCBlock;
zc->blockState.prevCBlock = zc->blockState.nextCBlock; zc->blockState.prevCBlock = zc->blockState.nextCBlock;
@ -2323,16 +2340,6 @@ static void ZSTD_overflowCorrectIfNeeded(ZSTD_matchState_t* ms, ZSTD_CCtx_params
} }
} }
/* Returns true if the given block is a RLE block */
static int ZSTD_isRLE(const BYTE *ip, size_t length) {
if (length < 2) return 1;
size_t i;
for (i = 1; i < length; ++i) {
if (ip[0] != ip[i]) return 0;
}
return 1;
}
/*! ZSTD_compress_frameChunk() : /*! ZSTD_compress_frameChunk() :
* Compress a chunk of data into one or multiple blocks. * Compress a chunk of data into one or multiple blocks.
* All blocks will be terminated, all input will be consumed. * All blocks will be terminated, all input will be consumed.
@ -2381,21 +2388,11 @@ static size_t ZSTD_compress_frameChunk (ZSTD_CCtx* cctx,
cSize = ZSTD_noCompressBlock(op, dstCapacity, ip, blockSize, lastBlock); cSize = ZSTD_noCompressBlock(op, dstCapacity, ip, blockSize, lastBlock);
FORWARD_IF_ERROR(cSize); FORWARD_IF_ERROR(cSize);
} else { } else {
U32 cBlockHeader; const U32 cBlockHeader = cSize == 1 ?
/* lastBlock + (((U32)bt_rle)<<1) + (U32)(blockSize << 3) :
We check to see if the regularly compressed block size is lastBlock + (((U32)bt_compressed)<<1) + (U32)(cSize << 3);
less than 10 (the upper bound for RLE blocks) and we check
to see if the block is an RLE
*/
if (cSize < 10 && ZSTD_isRLE(ip, blockSize)) {
op[ZSTD_blockHeaderSize] = ip[0];
cBlockHeader = lastBlock + (((U32)bt_rle)<<1) + (U32)(blockSize << 3);
cSize = ZSTD_blockHeaderSize + 1;
} else {
cBlockHeader = lastBlock + (((U32)bt_compressed)<<1) + (U32)(cSize << 3);
cSize += ZSTD_blockHeaderSize;
}
MEM_writeLE24(op, (const U32) cBlockHeader); MEM_writeLE24(op, (const U32) cBlockHeader);
cSize += ZSTD_blockHeaderSize;
} }
ip += blockSize; ip += blockSize;