vectorscan/src/nfa/truffle.c
2016-07-08 11:07:50 +10:00

326 lines
9.5 KiB
C

/*
* Copyright (c) 2015-2016, Intel Corporation
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* * Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* * Neither the name of Intel Corporation nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
/*
* Matches a byte in a charclass using three shuffles
*/
#include "ue2common.h"
#include "truffle.h"
#include "util/bitutils.h"
#include "util/simd_utils.h"
#include "truffle_common.h"
#if !defined(__AVX2__)
static really_inline
const u8 *lastMatch(const u8 *buf, u32 z) {
if (unlikely(z != 0xffff)) {
u32 pos = clz32(~z & 0xffff);
assert(pos >= 16 && pos < 32);
return buf + (31 - pos);
}
return NULL; // no match
}
static really_inline
const u8 *fwdBlock(m128 shuf_mask_lo_highclear, m128 shuf_mask_lo_highset,
m128 v, const u8 *buf) {
u32 z = block(shuf_mask_lo_highclear, shuf_mask_lo_highset, v);
return firstMatch(buf, z);
}
static really_inline
const u8 *revBlock(m128 shuf_mask_lo_highclear, m128 shuf_mask_lo_highset,
m128 v, const u8 *buf) {
u32 z = block(shuf_mask_lo_highclear, shuf_mask_lo_highset, v);
return lastMatch(buf, z);
}
const u8 *truffleExec(m128 shuf_mask_lo_highclear,
m128 shuf_mask_lo_highset,
const u8 *buf, const u8 *buf_end) {
DEBUG_PRINTF("len %zu\n", buf_end - buf);
assert(buf && buf_end);
assert(buf < buf_end);
const u8 *rv;
if (buf_end - buf < 16) {
return truffleMini(shuf_mask_lo_highclear, shuf_mask_lo_highset, buf,
buf_end);
}
size_t min = (size_t)buf % 16;
assert(buf_end - buf >= 16);
// Preconditioning: most of the time our buffer won't be aligned.
m128 chars = loadu128(buf);
rv = fwdBlock(shuf_mask_lo_highclear, shuf_mask_lo_highset, chars, buf);
if (rv) {
return rv;
}
buf += (16 - min);
const u8 *last_block = buf_end - 16;
while (buf < last_block) {
m128 lchars = load128(buf);
rv = fwdBlock(shuf_mask_lo_highclear, shuf_mask_lo_highset, lchars,
buf);
if (rv) {
return rv;
}
buf += 16;
}
// Use an unaligned load to mop up the last 16 bytes and get an accurate
// picture to buf_end.
assert(buf <= buf_end && buf >= buf_end - 16);
chars = loadu128(buf_end - 16);
rv = fwdBlock(shuf_mask_lo_highclear, shuf_mask_lo_highset, chars,
buf_end - 16);
if (rv) {
return rv;
}
return buf_end;
}
static
const u8 *truffleRevMini(m128 shuf_mask_lo_highclear,
m128 shuf_mask_lo_highset, const u8 *buf,
const u8 *buf_end) {
uintptr_t len = buf_end - buf;
assert(len < 16);
m128 chars = zeroes128();
memcpy(&chars, buf, len);
u32 mask = (0xFFFF >> (16 - len)) ^ 0xFFFF;
u32 z = block(shuf_mask_lo_highclear, shuf_mask_lo_highset, chars);
const u8 *rv = lastMatch(buf, z | mask);
if (rv) {
return rv;
}
return buf - 1;
}
const u8 *rtruffleExec(m128 shuf_mask_lo_highclear,
m128 shuf_mask_lo_highset,
const u8 *buf, const u8 *buf_end) {
assert(buf && buf_end);
assert(buf < buf_end);
const u8 *rv;
DEBUG_PRINTF("len %zu\n", buf_end - buf);
if (buf_end - buf < 16) {
return truffleRevMini(shuf_mask_lo_highclear, shuf_mask_lo_highset, buf,
buf_end);
}
assert(buf_end - buf >= 16);
// Preconditioning: most of the time our buffer won't be aligned.
m128 chars = loadu128(buf_end - 16);
rv = revBlock(shuf_mask_lo_highclear, shuf_mask_lo_highset, chars,
buf_end - 16);
if (rv) {
return rv;
}
buf_end = (const u8 *)((size_t)buf_end & ~((size_t)0xf));
const u8 *last_block = buf + 16;
while (buf_end > last_block) {
buf_end -= 16;
m128 lchars = load128(buf_end);
rv = revBlock(shuf_mask_lo_highclear, shuf_mask_lo_highset, lchars,
buf_end);
if (rv) {
return rv;
}
}
// Use an unaligned load to mop up the last 16 bytes and get an accurate
// picture to buf_end.
chars = loadu128(buf);
rv = revBlock(shuf_mask_lo_highclear, shuf_mask_lo_highset, chars, buf);
if (rv) {
return rv;
}
return buf - 1;
}
#else
static really_inline
const u8 *lastMatch(const u8 *buf, u32 z) {
if (unlikely(z != 0xffffffff)) {
u32 pos = clz32(~z);
assert(pos < 32);
return buf + (31 - pos);
}
return NULL; // no match
}
static really_inline
const u8 *fwdBlock(m256 shuf_mask_lo_highclear, m256 shuf_mask_lo_highset,
m256 v, const u8 *buf) {
u32 z = block(shuf_mask_lo_highclear, shuf_mask_lo_highset, v);
return firstMatch(buf, z);
}
static really_inline
const u8 *revBlock(m256 shuf_mask_lo_highclear, m256 shuf_mask_lo_highset,
m256 v, const u8 *buf) {
u32 z = block(shuf_mask_lo_highclear, shuf_mask_lo_highset, v);
return lastMatch(buf, z);
}
const u8 *truffleExec(m128 shuf_mask_lo_highclear,
m128 shuf_mask_lo_highset,
const u8 *buf, const u8 *buf_end) {
DEBUG_PRINTF("len %zu\n", buf_end - buf);
const m256 wide_clear = set2x128(shuf_mask_lo_highclear);
const m256 wide_set = set2x128(shuf_mask_lo_highset);
assert(buf && buf_end);
assert(buf < buf_end);
const u8 *rv;
if (buf_end - buf < 32) {
return truffleMini(wide_clear, wide_set, buf, buf_end);
}
size_t min = (size_t)buf % 32;
assert(buf_end - buf >= 32);
// Preconditioning: most of the time our buffer won't be aligned.
m256 chars = loadu256(buf);
rv = fwdBlock(wide_clear, wide_set, chars, buf);
if (rv) {
return rv;
}
buf += (32 - min);
const u8 *last_block = buf_end - 32;
while (buf < last_block) {
m256 lchars = load256(buf);
rv = fwdBlock(wide_clear, wide_set, lchars, buf);
if (rv) {
return rv;
}
buf += 32;
}
// Use an unaligned load to mop up the last 32 bytes and get an accurate
// picture to buf_end.
assert(buf <= buf_end && buf >= buf_end - 32);
chars = loadu256(buf_end - 32);
rv = fwdBlock(wide_clear, wide_set, chars, buf_end - 32);
if (rv) {
return rv;
}
return buf_end;
}
static
const u8 *truffleRevMini(m256 shuf_mask_lo_highclear,
m256 shuf_mask_lo_highset, const u8 *buf,
const u8 *buf_end) {
uintptr_t len = buf_end - buf;
assert(len < 32);
m256 chars = zeroes256();
memcpy(&chars, buf, len);
u32 mask = (0xFFFFFFFF >> (32 - len)) ^ 0xFFFFFFFF;
u32 z = block(shuf_mask_lo_highclear, shuf_mask_lo_highset, chars);
const u8 *rv = lastMatch(buf, z | mask);
if (rv) {
return rv;
}
return buf - 1;
}
const u8 *rtruffleExec(m128 shuf_mask_lo_highclear,
m128 shuf_mask_lo_highset,
const u8 *buf, const u8 *buf_end) {
const m256 wide_clear = set2x128(shuf_mask_lo_highclear);
const m256 wide_set = set2x128(shuf_mask_lo_highset);
assert(buf && buf_end);
assert(buf < buf_end);
const u8 *rv;
DEBUG_PRINTF("len %zu\n", buf_end - buf);
if (buf_end - buf < 32) {
return truffleRevMini(wide_clear, wide_set, buf, buf_end);
}
assert(buf_end - buf >= 32);
// Preconditioning: most of the time our buffer won't be aligned.
m256 chars = loadu256(buf_end - 32);
rv = revBlock(wide_clear, wide_set, chars,
buf_end - 32);
if (rv) {
return rv;
}
buf_end = (const u8 *)((size_t)buf_end & ~((size_t)0x1f));
const u8 *last_block = buf + 32;
while (buf_end > last_block) {
buf_end -= 32;
m256 lchars = load256(buf_end);
rv = revBlock(wide_clear, wide_set, lchars, buf_end);
if (rv) {
return rv;
}
}
// Use an unaligned load to mop up the last 32 bytes and get an accurate
// picture to buf_end.
chars = loadu256(buf);
rv = revBlock(wide_clear, wide_set, chars, buf);
if (rv) {
return rv;
}
return buf - 1;
}
#endif