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author | Markus F.X.J. Oberhumer <markus@oberhumer.com> | 2012-08-13 17:25:44 +0200 |
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committer | Markus F.X.J. Oberhumer <markus@oberhumer.com> | 2013-02-20 19:36:01 +0100 |
commit | 8b975bd3f9089f8ee5d7bbfd798537b992bbc7e7 (patch) | |
tree | 09078bdf5e805a5f921d8b7b592262ef3e877937 /lib/lzo/lzo1x_compress.c | |
parent | b6bec26cea948148a9420e7a0ac337f925de49e7 (diff) | |
download | op-kernel-dev-8b975bd3f9089f8ee5d7bbfd798537b992bbc7e7.zip op-kernel-dev-8b975bd3f9089f8ee5d7bbfd798537b992bbc7e7.tar.gz |
lib/lzo: Update LZO compression to current upstream version
This commit updates the kernel LZO code to the current upsteam version
which features a significant speed improvement - benchmarking the Calgary
and Silesia test corpora typically shows a doubled performance in
both compression and decompression on modern i386/x86_64/powerpc machines.
Signed-off-by: Markus F.X.J. Oberhumer <markus@oberhumer.com>
Diffstat (limited to 'lib/lzo/lzo1x_compress.c')
-rw-r--r-- | lib/lzo/lzo1x_compress.c | 335 |
1 files changed, 194 insertions, 141 deletions
diff --git a/lib/lzo/lzo1x_compress.c b/lib/lzo/lzo1x_compress.c index a604099..236eb21 100644 --- a/lib/lzo/lzo1x_compress.c +++ b/lib/lzo/lzo1x_compress.c @@ -1,194 +1,243 @@ /* - * LZO1X Compressor from MiniLZO + * LZO1X Compressor from LZO * - * Copyright (C) 1996-2005 Markus F.X.J. Oberhumer <markus@oberhumer.com> + * Copyright (C) 1996-2012 Markus F.X.J. Oberhumer <markus@oberhumer.com> * * The full LZO package can be found at: * http://www.oberhumer.com/opensource/lzo/ * - * Changed for kernel use by: + * Changed for Linux kernel use by: * Nitin Gupta <nitingupta910@gmail.com> * Richard Purdie <rpurdie@openedhand.com> */ #include <linux/module.h> #include <linux/kernel.h> -#include <linux/lzo.h> #include <asm/unaligned.h> +#include <linux/lzo.h> #include "lzodefs.h" static noinline size_t -_lzo1x_1_do_compress(const unsigned char *in, size_t in_len, - unsigned char *out, size_t *out_len, void *wrkmem) +lzo1x_1_do_compress(const unsigned char *in, size_t in_len, + unsigned char *out, size_t *out_len, + size_t ti, void *wrkmem) { + const unsigned char *ip; + unsigned char *op; const unsigned char * const in_end = in + in_len; - const unsigned char * const ip_end = in + in_len - M2_MAX_LEN - 5; - const unsigned char ** const dict = wrkmem; - const unsigned char *ip = in, *ii = ip; - const unsigned char *end, *m, *m_pos; - size_t m_off, m_len, dindex; - unsigned char *op = out; + const unsigned char * const ip_end = in + in_len - 20; + const unsigned char *ii; + lzo_dict_t * const dict = (lzo_dict_t *) wrkmem; - ip += 4; + op = out; + ip = in; + ii = ip; + ip += ti < 4 ? 4 - ti : 0; for (;;) { - dindex = ((size_t)(0x21 * DX3(ip, 5, 5, 6)) >> 5) & D_MASK; - m_pos = dict[dindex]; - - if (m_pos < in) - goto literal; - - if (ip == m_pos || ((size_t)(ip - m_pos) > M4_MAX_OFFSET)) - goto literal; - - m_off = ip - m_pos; - if (m_off <= M2_MAX_OFFSET || m_pos[3] == ip[3]) - goto try_match; - - dindex = (dindex & (D_MASK & 0x7ff)) ^ (D_HIGH | 0x1f); - m_pos = dict[dindex]; - - if (m_pos < in) - goto literal; - - if (ip == m_pos || ((size_t)(ip - m_pos) > M4_MAX_OFFSET)) - goto literal; - - m_off = ip - m_pos; - if (m_off <= M2_MAX_OFFSET || m_pos[3] == ip[3]) - goto try_match; - - goto literal; - -try_match: - if (get_unaligned((const unsigned short *)m_pos) - == get_unaligned((const unsigned short *)ip)) { - if (likely(m_pos[2] == ip[2])) - goto match; - } - + const unsigned char *m_pos; + size_t t, m_len, m_off; + u32 dv; literal: - dict[dindex] = ip; - ++ip; + ip += 1 + ((ip - ii) >> 5); +next: if (unlikely(ip >= ip_end)) break; - continue; - -match: - dict[dindex] = ip; - if (ip != ii) { - size_t t = ip - ii; + dv = get_unaligned_le32(ip); + t = ((dv * 0x1824429d) >> (32 - D_BITS)) & D_MASK; + m_pos = in + dict[t]; + dict[t] = (lzo_dict_t) (ip - in); + if (unlikely(dv != get_unaligned_le32(m_pos))) + goto literal; + ii -= ti; + ti = 0; + t = ip - ii; + if (t != 0) { if (t <= 3) { op[-2] |= t; - } else if (t <= 18) { + COPY4(op, ii); + op += t; + } else if (t <= 16) { *op++ = (t - 3); + COPY8(op, ii); + COPY8(op + 8, ii + 8); + op += t; } else { - size_t tt = t - 18; - - *op++ = 0; - while (tt > 255) { - tt -= 255; + if (t <= 18) { + *op++ = (t - 3); + } else { + size_t tt = t - 18; *op++ = 0; + while (unlikely(tt > 255)) { + tt -= 255; + *op++ = 0; + } + *op++ = tt; } - *op++ = tt; + do { + COPY8(op, ii); + COPY8(op + 8, ii + 8); + op += 16; + ii += 16; + t -= 16; + } while (t >= 16); + if (t > 0) do { + *op++ = *ii++; + } while (--t > 0); } - do { - *op++ = *ii++; - } while (--t > 0); } - ip += 3; - if (m_pos[3] != *ip++ || m_pos[4] != *ip++ - || m_pos[5] != *ip++ || m_pos[6] != *ip++ - || m_pos[7] != *ip++ || m_pos[8] != *ip++) { - --ip; - m_len = ip - ii; + m_len = 4; + { +#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && defined(LZO_USE_CTZ64) + u64 v; + v = get_unaligned((const u64 *) (ip + m_len)) ^ + get_unaligned((const u64 *) (m_pos + m_len)); + if (unlikely(v == 0)) { + do { + m_len += 8; + v = get_unaligned((const u64 *) (ip + m_len)) ^ + get_unaligned((const u64 *) (m_pos + m_len)); + if (unlikely(ip + m_len >= ip_end)) + goto m_len_done; + } while (v == 0); + } +# if defined(__LITTLE_ENDIAN) + m_len += (unsigned) __builtin_ctzll(v) / 8; +# elif defined(__BIG_ENDIAN) + m_len += (unsigned) __builtin_clzll(v) / 8; +# else +# error "missing endian definition" +# endif +#elif defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && defined(LZO_USE_CTZ32) + u32 v; + v = get_unaligned((const u32 *) (ip + m_len)) ^ + get_unaligned((const u32 *) (m_pos + m_len)); + if (unlikely(v == 0)) { + do { + m_len += 4; + v = get_unaligned((const u32 *) (ip + m_len)) ^ + get_unaligned((const u32 *) (m_pos + m_len)); + if (v != 0) + break; + m_len += 4; + v = get_unaligned((const u32 *) (ip + m_len)) ^ + get_unaligned((const u32 *) (m_pos + m_len)); + if (unlikely(ip + m_len >= ip_end)) + goto m_len_done; + } while (v == 0); + } +# if defined(__LITTLE_ENDIAN) + m_len += (unsigned) __builtin_ctz(v) / 8; +# elif defined(__BIG_ENDIAN) + m_len += (unsigned) __builtin_clz(v) / 8; +# else +# error "missing endian definition" +# endif +#else + if (unlikely(ip[m_len] == m_pos[m_len])) { + do { + m_len += 1; + if (ip[m_len] != m_pos[m_len]) + break; + m_len += 1; + if (ip[m_len] != m_pos[m_len]) + break; + m_len += 1; + if (ip[m_len] != m_pos[m_len]) + break; + m_len += 1; + if (ip[m_len] != m_pos[m_len]) + break; + m_len += 1; + if (ip[m_len] != m_pos[m_len]) + break; + m_len += 1; + if (ip[m_len] != m_pos[m_len]) + break; + m_len += 1; + if (ip[m_len] != m_pos[m_len]) + break; + m_len += 1; + if (unlikely(ip + m_len >= ip_end)) + goto m_len_done; + } while (ip[m_len] == m_pos[m_len]); + } +#endif + } +m_len_done: - if (m_off <= M2_MAX_OFFSET) { - m_off -= 1; - *op++ = (((m_len - 1) << 5) - | ((m_off & 7) << 2)); - *op++ = (m_off >> 3); - } else if (m_off <= M3_MAX_OFFSET) { - m_off -= 1; + m_off = ip - m_pos; + ip += m_len; + ii = ip; + if (m_len <= M2_MAX_LEN && m_off <= M2_MAX_OFFSET) { + m_off -= 1; + *op++ = (((m_len - 1) << 5) | ((m_off & 7) << 2)); + *op++ = (m_off >> 3); + } else if (m_off <= M3_MAX_OFFSET) { + m_off -= 1; + if (m_len <= M3_MAX_LEN) *op++ = (M3_MARKER | (m_len - 2)); - goto m3_m4_offset; - } else { - m_off -= 0x4000; - - *op++ = (M4_MARKER | ((m_off & 0x4000) >> 11) - | (m_len - 2)); - goto m3_m4_offset; + else { + m_len -= M3_MAX_LEN; + *op++ = M3_MARKER | 0; + while (unlikely(m_len > 255)) { + m_len -= 255; + *op++ = 0; + } + *op++ = (m_len); } + *op++ = (m_off << 2); + *op++ = (m_off >> 6); } else { - end = in_end; - m = m_pos + M2_MAX_LEN + 1; - - while (ip < end && *m == *ip) { - m++; - ip++; - } - m_len = ip - ii; - - if (m_off <= M3_MAX_OFFSET) { - m_off -= 1; - if (m_len <= 33) { - *op++ = (M3_MARKER | (m_len - 2)); - } else { - m_len -= 33; - *op++ = M3_MARKER | 0; - goto m3_m4_len; - } - } else { - m_off -= 0x4000; - if (m_len <= M4_MAX_LEN) { - *op++ = (M4_MARKER - | ((m_off & 0x4000) >> 11) + m_off -= 0x4000; + if (m_len <= M4_MAX_LEN) + *op++ = (M4_MARKER | ((m_off >> 11) & 8) | (m_len - 2)); - } else { - m_len -= M4_MAX_LEN; - *op++ = (M4_MARKER - | ((m_off & 0x4000) >> 11)); -m3_m4_len: - while (m_len > 255) { - m_len -= 255; - *op++ = 0; - } - - *op++ = (m_len); + else { + m_len -= M4_MAX_LEN; + *op++ = (M4_MARKER | ((m_off >> 11) & 8)); + while (unlikely(m_len > 255)) { + m_len -= 255; + *op++ = 0; } + *op++ = (m_len); } -m3_m4_offset: - *op++ = ((m_off & 63) << 2); + *op++ = (m_off << 2); *op++ = (m_off >> 6); } - - ii = ip; - if (unlikely(ip >= ip_end)) - break; + goto next; } - *out_len = op - out; - return in_end - ii; + return in_end - (ii - ti); } -int lzo1x_1_compress(const unsigned char *in, size_t in_len, unsigned char *out, - size_t *out_len, void *wrkmem) +int lzo1x_1_compress(const unsigned char *in, size_t in_len, + unsigned char *out, size_t *out_len, + void *wrkmem) { - const unsigned char *ii; + const unsigned char *ip = in; unsigned char *op = out; - size_t t; + size_t l = in_len; + size_t t = 0; - if (unlikely(in_len <= M2_MAX_LEN + 5)) { - t = in_len; - } else { - t = _lzo1x_1_do_compress(in, in_len, op, out_len, wrkmem); + while (l > 20) { + size_t ll = l <= (M4_MAX_OFFSET + 1) ? l : (M4_MAX_OFFSET + 1); + uintptr_t ll_end = (uintptr_t) ip + ll; + if ((ll_end + ((t + ll) >> 5)) <= ll_end) + break; + BUILD_BUG_ON(D_SIZE * sizeof(lzo_dict_t) > LZO1X_1_MEM_COMPRESS); + memset(wrkmem, 0, D_SIZE * sizeof(lzo_dict_t)); + t = lzo1x_1_do_compress(ip, ll, op, out_len, t, wrkmem); + ip += ll; op += *out_len; + l -= ll; } + t += l; if (t > 0) { - ii = in + in_len - t; + const unsigned char *ii = in + in_len - t; if (op == out && t <= 238) { *op++ = (17 + t); @@ -198,16 +247,21 @@ int lzo1x_1_compress(const unsigned char *in, size_t in_len, unsigned char *out, *op++ = (t - 3); } else { size_t tt = t - 18; - *op++ = 0; while (tt > 255) { tt -= 255; *op++ = 0; } - *op++ = tt; } - do { + if (t >= 16) do { + COPY8(op, ii); + COPY8(op + 8, ii + 8); + op += 16; + ii += 16; + t -= 16; + } while (t >= 16); + if (t > 0) do { *op++ = *ii++; } while (--t > 0); } @@ -223,4 +277,3 @@ EXPORT_SYMBOL_GPL(lzo1x_1_compress); MODULE_LICENSE("GPL"); MODULE_DESCRIPTION("LZO1X-1 Compressor"); - |