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author | Markus F.X.J. Oberhumer <markus@oberhumer.com> | 2012-08-13 19:25:44 +0400 |
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committer | Markus F.X.J. Oberhumer <markus@oberhumer.com> | 2013-02-20 22:36:01 +0400 |
commit | 8b975bd3f9089f8ee5d7bbfd798537b992bbc7e7 (patch) | |
tree | 09078bdf5e805a5f921d8b7b592262ef3e877937 /lib/lzo/lzo1x_decompress_safe.c | |
parent | b6bec26cea948148a9420e7a0ac337f925de49e7 (diff) | |
download | linux-8b975bd3f9089f8ee5d7bbfd798537b992bbc7e7.tar.xz |
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_decompress_safe.c')
-rw-r--r-- | lib/lzo/lzo1x_decompress_safe.c | 350 |
1 files changed, 166 insertions, 184 deletions
diff --git a/lib/lzo/lzo1x_decompress_safe.c b/lib/lzo/lzo1x_decompress_safe.c index f2fd09850223..569985d522d5 100644 --- a/lib/lzo/lzo1x_decompress_safe.c +++ b/lib/lzo/lzo1x_decompress_safe.c @@ -1,12 +1,12 @@ /* - * LZO1X Decompressor from MiniLZO + * LZO1X Decompressor 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> */ @@ -15,225 +15,207 @@ #include <linux/module.h> #include <linux/kernel.h> #endif - #include <asm/unaligned.h> #include <linux/lzo.h> #include "lzodefs.h" -#define HAVE_IP(x, ip_end, ip) ((size_t)(ip_end - ip) < (x)) -#define HAVE_OP(x, op_end, op) ((size_t)(op_end - op) < (x)) -#define HAVE_LB(m_pos, out, op) (m_pos < out || m_pos >= op) - -#define COPY4(dst, src) \ - put_unaligned(get_unaligned((const u32 *)(src)), (u32 *)(dst)) +#define HAVE_IP(x) ((size_t)(ip_end - ip) >= (size_t)(x)) +#define HAVE_OP(x) ((size_t)(op_end - op) >= (size_t)(x)) +#define NEED_IP(x) if (!HAVE_IP(x)) goto input_overrun +#define NEED_OP(x) if (!HAVE_OP(x)) goto output_overrun +#define TEST_LB(m_pos) if ((m_pos) < out) goto lookbehind_overrun int lzo1x_decompress_safe(const unsigned char *in, size_t in_len, - unsigned char *out, size_t *out_len) + unsigned char *out, size_t *out_len) { + unsigned char *op; + const unsigned char *ip; + size_t t, next; + size_t state = 0; + const unsigned char *m_pos; const unsigned char * const ip_end = in + in_len; unsigned char * const op_end = out + *out_len; - const unsigned char *ip = in, *m_pos; - unsigned char *op = out; - size_t t; - *out_len = 0; + op = out; + ip = in; + if (unlikely(in_len < 3)) + goto input_overrun; if (*ip > 17) { t = *ip++ - 17; - if (t < 4) + if (t < 4) { + next = t; goto match_next; - if (HAVE_OP(t, op_end, op)) - goto output_overrun; - if (HAVE_IP(t + 1, ip_end, ip)) - goto input_overrun; - do { - *op++ = *ip++; - } while (--t > 0); - goto first_literal_run; - } - - while ((ip < ip_end)) { - t = *ip++; - if (t >= 16) - goto match; - if (t == 0) { - if (HAVE_IP(1, ip_end, ip)) - goto input_overrun; - while (*ip == 0) { - t += 255; - ip++; - if (HAVE_IP(1, ip_end, ip)) - goto input_overrun; - } - t += 15 + *ip++; - } - if (HAVE_OP(t + 3, op_end, op)) - goto output_overrun; - if (HAVE_IP(t + 4, ip_end, ip)) - goto input_overrun; - - COPY4(op, ip); - op += 4; - ip += 4; - if (--t > 0) { - if (t >= 4) { - do { - COPY4(op, ip); - op += 4; - ip += 4; - t -= 4; - } while (t >= 4); - if (t > 0) { - do { - *op++ = *ip++; - } while (--t > 0); - } - } else { - do { - *op++ = *ip++; - } while (--t > 0); - } } + goto copy_literal_run; + } -first_literal_run: + for (;;) { t = *ip++; - if (t >= 16) - goto match; - m_pos = op - (1 + M2_MAX_OFFSET); - m_pos -= t >> 2; - m_pos -= *ip++ << 2; - - if (HAVE_LB(m_pos, out, op)) - goto lookbehind_overrun; - - if (HAVE_OP(3, op_end, op)) - goto output_overrun; - *op++ = *m_pos++; - *op++ = *m_pos++; - *op++ = *m_pos; - - goto match_done; - - do { -match: - if (t >= 64) { - m_pos = op - 1; - m_pos -= (t >> 2) & 7; - m_pos -= *ip++ << 3; - t = (t >> 5) - 1; - if (HAVE_LB(m_pos, out, op)) - goto lookbehind_overrun; - if (HAVE_OP(t + 3 - 1, op_end, op)) - goto output_overrun; - goto copy_match; - } else if (t >= 32) { - t &= 31; - if (t == 0) { - if (HAVE_IP(1, ip_end, ip)) - goto input_overrun; - while (*ip == 0) { + if (t < 16) { + if (likely(state == 0)) { + if (unlikely(t == 0)) { + while (unlikely(*ip == 0)) { t += 255; ip++; - if (HAVE_IP(1, ip_end, ip)) - goto input_overrun; + NEED_IP(1); } - t += 31 + *ip++; + t += 15 + *ip++; } - m_pos = op - 1; - m_pos -= get_unaligned_le16(ip) >> 2; - ip += 2; - } else if (t >= 16) { - m_pos = op; - m_pos -= (t & 8) << 11; - - t &= 7; - if (t == 0) { - if (HAVE_IP(1, ip_end, ip)) - goto input_overrun; - while (*ip == 0) { - t += 255; - ip++; - if (HAVE_IP(1, ip_end, ip)) - goto input_overrun; - } - t += 7 + *ip++; + t += 3; +copy_literal_run: +#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) + if (likely(HAVE_IP(t + 15) && HAVE_OP(t + 15))) { + const unsigned char *ie = ip + t; + unsigned char *oe = op + t; + do { + COPY8(op, ip); + op += 8; + ip += 8; + COPY8(op, ip); + op += 8; + ip += 8; + } while (ip < ie); + ip = ie; + op = oe; + } else +#endif + { + NEED_OP(t); + NEED_IP(t + 3); + do { + *op++ = *ip++; + } while (--t > 0); } - m_pos -= get_unaligned_le16(ip) >> 2; - ip += 2; - if (m_pos == op) - goto eof_found; - m_pos -= 0x4000; - } else { + state = 4; + continue; + } else if (state != 4) { + next = t & 3; m_pos = op - 1; m_pos -= t >> 2; m_pos -= *ip++ << 2; - - if (HAVE_LB(m_pos, out, op)) - goto lookbehind_overrun; - if (HAVE_OP(2, op_end, op)) - goto output_overrun; - - *op++ = *m_pos++; - *op++ = *m_pos; - goto match_done; + TEST_LB(m_pos); + NEED_OP(2); + op[0] = m_pos[0]; + op[1] = m_pos[1]; + op += 2; + goto match_next; + } else { + next = t & 3; + m_pos = op - (1 + M2_MAX_OFFSET); + m_pos -= t >> 2; + m_pos -= *ip++ << 2; + t = 3; } - - if (HAVE_LB(m_pos, out, op)) - goto lookbehind_overrun; - if (HAVE_OP(t + 3 - 1, op_end, op)) - goto output_overrun; - - if (t >= 2 * 4 - (3 - 1) && (op - m_pos) >= 4) { - COPY4(op, m_pos); - op += 4; - m_pos += 4; - t -= 4 - (3 - 1); + } else if (t >= 64) { + next = t & 3; + m_pos = op - 1; + m_pos -= (t >> 2) & 7; + m_pos -= *ip++ << 3; + t = (t >> 5) - 1 + (3 - 1); + } else if (t >= 32) { + t = (t & 31) + (3 - 1); + if (unlikely(t == 2)) { + while (unlikely(*ip == 0)) { + t += 255; + ip++; + NEED_IP(1); + } + t += 31 + *ip++; + NEED_IP(2); + } + m_pos = op - 1; + next = get_unaligned_le16(ip); + ip += 2; + m_pos -= next >> 2; + next &= 3; + } else { + m_pos = op; + m_pos -= (t & 8) << 11; + t = (t & 7) + (3 - 1); + if (unlikely(t == 2)) { + while (unlikely(*ip == 0)) { + t += 255; + ip++; + NEED_IP(1); + } + t += 7 + *ip++; + NEED_IP(2); + } + next = get_unaligned_le16(ip); + ip += 2; + m_pos -= next >> 2; + next &= 3; + if (m_pos == op) + goto eof_found; + m_pos -= 0x4000; + } + TEST_LB(m_pos); +#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) + if (op - m_pos >= 8) { + unsigned char *oe = op + t; + if (likely(HAVE_OP(t + 15))) { do { - COPY4(op, m_pos); - op += 4; - m_pos += 4; - t -= 4; - } while (t >= 4); - if (t > 0) - do { - *op++ = *m_pos++; - } while (--t > 0); + COPY8(op, m_pos); + op += 8; + m_pos += 8; + COPY8(op, m_pos); + op += 8; + m_pos += 8; + } while (op < oe); + op = oe; + if (HAVE_IP(6)) { + state = next; + COPY4(op, ip); + op += next; + ip += next; + continue; + } } else { -copy_match: - *op++ = *m_pos++; - *op++ = *m_pos++; + NEED_OP(t); do { *op++ = *m_pos++; - } while (--t > 0); + } while (op < oe); } -match_done: - t = ip[-2] & 3; - if (t == 0) - break; + } else +#endif + { + unsigned char *oe = op + t; + NEED_OP(t); + op[0] = m_pos[0]; + op[1] = m_pos[1]; + op += 2; + m_pos += 2; + do { + *op++ = *m_pos++; + } while (op < oe); + } match_next: - if (HAVE_OP(t, op_end, op)) - goto output_overrun; - if (HAVE_IP(t + 1, ip_end, ip)) - goto input_overrun; - - *op++ = *ip++; - if (t > 1) { + state = next; + t = next; +#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) + if (likely(HAVE_IP(6) && HAVE_OP(4))) { + COPY4(op, ip); + op += t; + ip += t; + } else +#endif + { + NEED_IP(t + 3); + NEED_OP(t); + while (t > 0) { *op++ = *ip++; - if (t > 2) - *op++ = *ip++; + t--; } - - t = *ip++; - } while (ip < ip_end); + } } - *out_len = op - out; - return LZO_E_EOF_NOT_FOUND; - eof_found: *out_len = op - out; - return (ip == ip_end ? LZO_E_OK : - (ip < ip_end ? LZO_E_INPUT_NOT_CONSUMED : LZO_E_INPUT_OVERRUN)); + return (t != 3 ? LZO_E_ERROR : + ip == ip_end ? LZO_E_OK : + ip < ip_end ? LZO_E_INPUT_NOT_CONSUMED : LZO_E_INPUT_OVERRUN); + input_overrun: *out_len = op - out; return LZO_E_INPUT_OVERRUN; |