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Diffstat (limited to 'fill_window_sse.c')
| -rw-r--r-- | fill_window_sse.c | 182 |
1 files changed, 0 insertions, 182 deletions
diff --git a/fill_window_sse.c b/fill_window_sse.c deleted file mode 100644 index a841c99..0000000 --- a/fill_window_sse.c +++ /dev/null @@ -1,182 +0,0 @@ -/* - * Fill Window with SSE2-optimized hash shifting - * - * Copyright (C) 2013 Intel Corporation - * Authors: - * Arjan van de Ven <arjan@linux.intel.com> - * Jim Kukunas <james.t.kukunas@linux.intel.com> - * - * For conditions of distribution and use, see copyright notice in zlib.h - */ - -#include "deflate.h" - -#ifdef DEFLATE_FILL_WINDOW_SSE2 - -#define UPDATE_HASH(s,h,i) \ - {\ - if (s->level < 6) { \ - h = (3483 * (s->window[i]) +\ - 23081* (s->window[i+1]) +\ - 6954 * (s->window[i+2]) +\ - 20947* (s->window[i+3])) & s->hash_mask;\ - } else {\ - h = (25881* (s->window[i]) +\ - 24674* (s->window[i+1]) +\ - 25811* (s->window[i+2])) & s->hash_mask;\ - }\ - }\ - -extern int deflate_read_buf OF((z_streamp strm, Bytef *buf, unsigned size)); - -#include <immintrin.h> - -void fill_window_sse(deflate_state *s) -{ - const __m128i xmm_wsize = _mm_set1_epi16(s->w_size); - - register unsigned n; - register Posf *p; - unsigned more; /* Amount of free space at the end of the window. */ - uInt wsize = s->w_size; - - Assert(s->lookahead < MIN_LOOKAHEAD, "already enough lookahead"); - - do { - more = (unsigned)(s->window_size -(ulg)s->lookahead -(ulg)s->strstart); - - /* Deal with !@#$% 64K limit: */ - if (sizeof(int) <= 2) { - if (more == 0 && s->strstart == 0 && s->lookahead == 0) { - more = wsize; - - } else if (more == (unsigned)(-1)) { - /* Very unlikely, but possible on 16 bit machine if - * strstart == 0 && lookahead == 1 (input done a byte at time) - */ - more--; - } - } - - /* If the window is almost full and there is insufficient lookahead, - * move the upper half to the lower one to make room in the upper half. - */ - if (s->strstart >= wsize+MAX_DIST(s)) { - - zmemcpy(s->window, s->window+wsize, (unsigned)wsize); - s->match_start -= wsize; - s->strstart -= wsize; /* we now have strstart >= MAX_DIST */ - s->block_start -= (long) wsize; - - /* Slide the hash table (could be avoided with 32 bit values - at the expense of memory usage). We slide even when level == 0 - to keep the hash table consistent if we switch back to level > 0 - later. (Using level 0 permanently is not an optimal usage of - zlib, so we don't care about this pathological case.) - */ - n = s->hash_size; - p = &s->head[n]; - p -= 8; - do { - __m128i value, result; - - value = _mm_loadu_si128((__m128i *)p); - result = _mm_subs_epu16(value, xmm_wsize); - _mm_storeu_si128((__m128i *)p, result); - - p -= 8; - n -= 8; - } while (n > 0); - - n = wsize; -#ifndef FASTEST - p = &s->prev[n]; - p -= 8; - do { - __m128i value, result; - - value = _mm_loadu_si128((__m128i *)p); - result = _mm_subs_epu16(value, xmm_wsize); - _mm_storeu_si128((__m128i *)p, result); - - p -= 8; - n -= 8; - } while (n > 0); -#endif - more += wsize; - } - if (s->strm->avail_in == 0) break; - - /* If there was no sliding: - * strstart <= WSIZE+MAX_DIST-1 && lookahead <= MIN_LOOKAHEAD - 1 && - * more == window_size - lookahead - strstart - * => more >= window_size - (MIN_LOOKAHEAD-1 + WSIZE + MAX_DIST-1) - * => more >= window_size - 2*WSIZE + 2 - * In the BIG_MEM or MMAP case (not yet supported), - * window_size == input_size + MIN_LOOKAHEAD && - * strstart + s->lookahead <= input_size => more >= MIN_LOOKAHEAD. - * Otherwise, window_size == 2*WSIZE so more >= 2. - * If there was sliding, more >= WSIZE. So in all cases, more >= 2. - */ - Assert(more >= 2, "more < 2"); - - n = deflate_read_buf(s->strm, - s->window + s->strstart + s->lookahead, - more); - s->lookahead += n; - - /* Initialize the hash value now that we have some input: */ - if (s->lookahead >= MIN_MATCH) { - uInt str = s->strstart; - s->ins_h = s->window[str]; - if (str >= 1) - UPDATE_HASH(s, s->ins_h, str + 1 - (MIN_MATCH-1)); -#if MIN_MATCH != 3 - Call UPDATE_HASH() MIN_MATCH-3 more times -#endif - } - /* If the whole input has less than MIN_MATCH bytes, ins_h is garbage, - * but this is not important since only literal bytes will be emitted. - */ - - } while (s->lookahead < MIN_LOOKAHEAD && s->strm->avail_in != 0); - - /* If the WIN_INIT bytes after the end of the current data have never been - * written, then zero those bytes in order to avoid memory check reports of - * the use of uninitialized (or uninitialised as Julian writes) bytes by - * the longest match routines. Update the high water mark for the next - * time through here. WIN_INIT is set to MAX_MATCH since the longest match - * routines allow scanning to strstart + MAX_MATCH, ignoring lookahead. - */ - if (s->high_water < s->window_size) { - ulg curr = s->strstart + (ulg)(s->lookahead); - ulg init; - - if (s->high_water < curr) { - /* Previous high water mark below current data -- zero WIN_INIT - * bytes or up to end of window, whichever is less. - */ - init = s->window_size - curr; - if (init > WIN_INIT) - init = WIN_INIT; - zmemzero(s->window + curr, (unsigned)init); - s->high_water = curr + init; - } - else if (s->high_water < (ulg)curr + WIN_INIT) { - /* High water mark at or above current data, but below current data - * plus WIN_INIT -- zero out to current data plus WIN_INIT, or up - * to end of window, whichever is less. - */ - init = (ulg)curr + WIN_INIT - s->high_water; - if (init > s->window_size - s->high_water) - init = s->window_size - s->high_water; - zmemzero(s->window + s->high_water, (unsigned)init); - s->high_water += init; - } - } - - Assert((ulg)s->strstart <= s->window_size - MIN_LOOKAHEAD, - "not enough room for search"); -} - -#endif /* DEFLATE_FILL_WINDOW_SSE2 */ |