| |
| /*-------------------------------------------------------------*/ |
| /*--- Block sorting machinery ---*/ |
| /*--- blocksort.c ---*/ |
| /*-------------------------------------------------------------*/ |
| |
| /*-- |
| This file is a part of bzip2 and/or libbzip2, a program and |
| library for lossless, block-sorting data compression. |
| |
| Copyright (C) 1996-2000 Julian R Seward. All rights reserved. |
| |
| Redistribution and use in source and binary forms, with or without |
| modification, are permitted provided that the following conditions |
| are met: |
| |
| 1. Redistributions of source code must retain the above copyright |
| notice, this list of conditions and the following disclaimer. |
| |
| 2. The origin of this software must not be misrepresented; you must |
| not claim that you wrote the original software. If you use this |
| software in a product, an acknowledgment in the product |
| documentation would be appreciated but is not required. |
| |
| 3. Altered source versions must be plainly marked as such, and must |
| not be misrepresented as being the original software. |
| |
| 4. The name of the author may not be used to endorse or promote |
| products derived from this software without specific prior written |
| permission. |
| |
| THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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. |
| |
| Julian Seward, Cambridge, UK. |
| jseward@acm.org |
| bzip2/libbzip2 version 1.0 of 21 March 2000 |
| |
| This program is based on (at least) the work of: |
| Mike Burrows |
| David Wheeler |
| Peter Fenwick |
| Alistair Moffat |
| Radford Neal |
| Ian H. Witten |
| Robert Sedgewick |
| Jon L. Bentley |
| |
| For more information on these sources, see the manual. |
| |
| To get some idea how the block sorting algorithms in this file |
| work, read my paper |
| On the Performance of BWT Sorting Algorithms |
| in Proceedings of the IEEE Data Compression Conference 2000, |
| Snowbird, Utah, USA, 27-30 March 2000. The main sort in this |
| file implements the algorithm called cache in the paper. |
| --*/ |
| |
| #include "os.h" |
| #include "bzlib.h" |
| #include "bzlib_private.h" |
| |
| /*---------------------------------------------*/ |
| /*--- Fallback O(N log(N)^2) sorting ---*/ |
| /*--- algorithm, for repetitive blocks ---*/ |
| /*---------------------------------------------*/ |
| |
| /*---------------------------------------------*/ |
| static |
| __inline__ |
| void fallbackSimpleSort ( UInt32* fmap, |
| UInt32* eclass, |
| Int32 lo, |
| Int32 hi ) |
| { |
| Int32 i, j, tmp; |
| UInt32 ec_tmp; |
| |
| if (lo == hi) return; |
| |
| if (hi - lo > 3) { |
| for ( i = hi-4; i >= lo; i-- ) { |
| tmp = fmap[i]; |
| ec_tmp = eclass[tmp]; |
| for ( j = i+4; j <= hi && ec_tmp > eclass[fmap[j]]; j += 4 ) |
| fmap[j-4] = fmap[j]; |
| fmap[j-4] = tmp; |
| } |
| } |
| |
| for ( i = hi-1; i >= lo; i-- ) { |
| tmp = fmap[i]; |
| ec_tmp = eclass[tmp]; |
| for ( j = i+1; j <= hi && ec_tmp > eclass[fmap[j]]; j++ ) |
| fmap[j-1] = fmap[j]; |
| fmap[j-1] = tmp; |
| } |
| } |
| |
| |
| /*---------------------------------------------*/ |
| #define fswap(zz1, zz2) \ |
| { Int32 zztmp = zz1; zz1 = zz2; zz2 = zztmp; } |
| |
| #define fvswap(zzp1, zzp2, zzn) \ |
| { \ |
| Int32 yyp1 = (zzp1); \ |
| Int32 yyp2 = (zzp2); \ |
| Int32 yyn = (zzn); \ |
| while (yyn > 0) { \ |
| fswap(fmap[yyp1], fmap[yyp2]); \ |
| yyp1++; yyp2++; yyn--; \ |
| } \ |
| } |
| |
| |
| #define fmin(a,b) ((a) < (b)) ? (a) : (b) |
| |
| #define fpush(lz,hz) { stackLo[sp] = lz; \ |
| stackHi[sp] = hz; \ |
| sp++; } |
| |
| #define fpop(lz,hz) { sp--; \ |
| lz = stackLo[sp]; \ |
| hz = stackHi[sp]; } |
| |
| #define FALLBACK_QSORT_SMALL_THRESH 10 |
| #define FALLBACK_QSORT_STACK_SIZE 100 |
| |
| |
| static |
| void fallbackQSort3 ( UInt32* fmap, |
| UInt32* eclass, |
| Int32 loSt, |
| Int32 hiSt ) |
| { |
| Int32 unLo, unHi, ltLo, gtHi, n, m; |
| Int32 sp, lo, hi; |
| UInt32 med, r, r3; |
| Int32 stackLo[FALLBACK_QSORT_STACK_SIZE]; |
| Int32 stackHi[FALLBACK_QSORT_STACK_SIZE]; |
| |
| r = 0; |
| |
| sp = 0; |
| fpush ( loSt, hiSt ); |
| |
| while (sp > 0) { |
| |
| AssertH ( sp < FALLBACK_QSORT_STACK_SIZE, 1004 ); |
| |
| fpop ( lo, hi ); |
| if (hi - lo < FALLBACK_QSORT_SMALL_THRESH) { |
| fallbackSimpleSort ( fmap, eclass, lo, hi ); |
| continue; |
| } |
| |
| /* Random partitioning. Median of 3 sometimes fails to |
| avoid bad cases. Median of 9 seems to help but |
| looks rather expensive. This too seems to work but |
| is cheaper. Guidance for the magic constants |
| 7621 and 32768 is taken from Sedgewick's algorithms |
| book, chapter 35. |
| */ |
| r = ((r * 7621) + 1) % 32768; |
| r3 = r % 3; |
| if (r3 == 0) med = eclass[fmap[lo]]; else |
| if (r3 == 1) med = eclass[fmap[(lo+hi)>>1]]; else |
| med = eclass[fmap[hi]]; |
| |
| unLo = ltLo = lo; |
| unHi = gtHi = hi; |
| |
| while (1) { |
| while (1) { |
| if (unLo > unHi) break; |
| n = (Int32)eclass[fmap[unLo]] - (Int32)med; |
| if (n == 0) { |
| fswap(fmap[unLo], fmap[ltLo]); |
| ltLo++; unLo++; |
| continue; |
| }; |
| if (n > 0) break; |
| unLo++; |
| } |
| while (1) { |
| if (unLo > unHi) break; |
| n = (Int32)eclass[fmap[unHi]] - (Int32)med; |
| if (n == 0) { |
| fswap(fmap[unHi], fmap[gtHi]); |
| gtHi--; unHi--; |
| continue; |
| }; |
| if (n < 0) break; |
| unHi--; |
| } |
| if (unLo > unHi) break; |
| fswap(fmap[unLo], fmap[unHi]); unLo++; unHi--; |
| } |
| |
| AssertD ( unHi == unLo-1, "fallbackQSort3(2)" ); |
| |
| if (gtHi < ltLo) continue; |
| |
| n = fmin(ltLo-lo, unLo-ltLo); fvswap(lo, unLo-n, n); |
| m = fmin(hi-gtHi, gtHi-unHi); fvswap(unLo, hi-m+1, m); |
| |
| n = lo + unLo - ltLo - 1; |
| m = hi - (gtHi - unHi) + 1; |
| |
| if (n - lo > hi - m) { |
| fpush ( lo, n ); |
| fpush ( m, hi ); |
| } else { |
| fpush ( m, hi ); |
| fpush ( lo, n ); |
| } |
| } |
| } |
| |
| #undef fmin |
| #undef fpush |
| #undef fpop |
| #undef fswap |
| #undef fvswap |
| #undef FALLBACK_QSORT_SMALL_THRESH |
| #undef FALLBACK_QSORT_STACK_SIZE |
| |
| |
| /*---------------------------------------------*/ |
| /* Pre: |
| nblock > 0 |
| eclass exists for [0 .. nblock-1] |
| ((UChar*)eclass) [0 .. nblock-1] holds block |
| ptr exists for [0 .. nblock-1] |
| |
| Post: |
| ((UChar*)eclass) [0 .. nblock-1] holds block |
| All other areas of eclass destroyed |
| fmap [0 .. nblock-1] holds sorted order |
| bhtab [ 0 .. 2+(nblock/32) ] destroyed |
| */ |
| |
| #define SET_BH(zz) bhtab[(zz) >> 5] |= (1 << ((zz) & 31)) |
| #define CLEAR_BH(zz) bhtab[(zz) >> 5] &= ~(1 << ((zz) & 31)) |
| #define ISSET_BH(zz) (bhtab[(zz) >> 5] & (1 << ((zz) & 31))) |
| #define WORD_BH(zz) bhtab[(zz) >> 5] |
| #define UNALIGNED_BH(zz) ((zz) & 0x01f) |
| |
| static |
| void fallbackSort ( UInt32* fmap, |
| UInt32* eclass, |
| UInt32* bhtab, |
| Int32 nblock, |
| Int32 verb ) |
| { |
| Int32 ftab[257]; |
| Int32 ftabCopy[256]; |
| Int32 H, i, j, k, l, r, cc, cc1; |
| Int32 nNotDone; |
| Int32 nBhtab; |
| UChar* eclass8 = (UChar*)eclass; |
| |
| /*-- |
| Initial 1-char radix sort to generate |
| initial fmap and initial BH bits. |
| --*/ |
| if (verb >= 4) |
| VPrintf0 ( " bucket sorting ...\n" ); |
| for (i = 0; i < 257; i++) ftab[i] = 0; |
| for (i = 0; i < nblock; i++) ftab[eclass8[i]]++; |
| for (i = 0; i < 256; i++) ftabCopy[i] = ftab[i]; |
| for (i = 1; i < 257; i++) ftab[i] += ftab[i-1]; |
| |
| for (i = 0; i < nblock; i++) { |
| j = eclass8[i]; |
| k = ftab[j] - 1; |
| ftab[j] = k; |
| fmap[k] = i; |
| } |
| |
| nBhtab = 2 + (nblock / 32); |
| for (i = 0; i < nBhtab; i++) bhtab[i] = 0; |
| for (i = 0; i < 256; i++) SET_BH(ftab[i]); |
| |
| /*-- |
| Inductively refine the buckets. Kind-of an |
| "exponential radix sort" (!), inspired by the |
| Manber-Myers suffix array construction algorithm. |
| --*/ |
| |
| /*-- set sentinel bits for block-end detection --*/ |
| for (i = 0; i < 32; i++) { |
| SET_BH(nblock + 2*i); |
| CLEAR_BH(nblock + 2*i + 1); |
| } |
| |
| /*-- the log(N) loop --*/ |
| H = 1; |
| while (1) { |
| |
| if (verb >= 4) |
| VPrintf1 ( " depth %6d has ", H ); |
| |
| j = 0; |
| for (i = 0; i < nblock; i++) { |
| if (ISSET_BH(i)) j = i; |
| k = fmap[i] - H; if (k < 0) k += nblock; |
| eclass[k] = j; |
| } |
| |
| nNotDone = 0; |
| r = -1; |
| while (1) { |
| |
| /*-- find the next non-singleton bucket --*/ |
| k = r + 1; |
| while (ISSET_BH(k) && UNALIGNED_BH(k)) k++; |
| if (ISSET_BH(k)) { |
| while (WORD_BH(k) == 0xffffffff) k += 32; |
| while (ISSET_BH(k)) k++; |
| } |
| l = k - 1; |
| if (l >= nblock) break; |
| while (!ISSET_BH(k) && UNALIGNED_BH(k)) k++; |
| if (!ISSET_BH(k)) { |
| while (WORD_BH(k) == 0x00000000) k += 32; |
| while (!ISSET_BH(k)) k++; |
| } |
| r = k - 1; |
| if (r >= nblock) break; |
| |
| /*-- now [l, r] bracket current bucket --*/ |
| if (r > l) { |
| nNotDone += (r - l + 1); |
| fallbackQSort3 ( fmap, eclass, l, r ); |
| |
| /*-- scan bucket and generate header bits-- */ |
| cc = -1; |
| for (i = l; i <= r; i++) { |
| cc1 = eclass[fmap[i]]; |
| if (cc != cc1) { SET_BH(i); cc = cc1; }; |
| } |
| } |
| } |
| |
| if (verb >= 4) |
| VPrintf1 ( "%6d unresolved strings\n", nNotDone ); |
| |
| H *= 2; |
| if (H > nblock || nNotDone == 0) break; |
| } |
| |
| /*-- |
| Reconstruct the original block in |
| eclass8 [0 .. nblock-1], since the |
| previous phase destroyed it. |
| --*/ |
| if (verb >= 4) |
| VPrintf0 ( " reconstructing block ...\n" ); |
| j = 0; |
| for (i = 0; i < nblock; i++) { |
| while (ftabCopy[j] == 0) j++; |
| ftabCopy[j]--; |
| eclass8[fmap[i]] = (UChar)j; |
| } |
| AssertH ( j < 256, 1005 ); |
| } |
| |
| #undef SET_BH |
| #undef CLEAR_BH |
| #undef ISSET_BH |
| #undef WORD_BH |
| #undef UNALIGNED_BH |
| |
| |
| /*---------------------------------------------*/ |
| /*--- The main, O(N^2 log(N)) sorting ---*/ |
| /*--- algorithm. Faster for "normal" ---*/ |
| /*--- non-repetitive blocks. ---*/ |
| /*---------------------------------------------*/ |
| |
| /*---------------------------------------------*/ |
| static |
| __inline__ |
| Bool mainGtU ( UInt32 i1, |
| UInt32 i2, |
| UChar* block, |
| UInt16* quadrant, |
| UInt32 nblock, |
| Int32* budget ) |
| { |
| Int32 k; |
| UChar c1, c2; |
| UInt16 s1, s2; |
| |
| AssertD ( i1 != i2, "mainGtU" ); |
| /* 1 */ |
| c1 = block[i1]; c2 = block[i2]; |
| if (c1 != c2) return (c1 > c2); |
| i1++; i2++; |
| /* 2 */ |
| c1 = block[i1]; c2 = block[i2]; |
| if (c1 != c2) return (c1 > c2); |
| i1++; i2++; |
| /* 3 */ |
| c1 = block[i1]; c2 = block[i2]; |
| if (c1 != c2) return (c1 > c2); |
| i1++; i2++; |
| /* 4 */ |
| c1 = block[i1]; c2 = block[i2]; |
| if (c1 != c2) return (c1 > c2); |
| i1++; i2++; |
| /* 5 */ |
| c1 = block[i1]; c2 = block[i2]; |
| if (c1 != c2) return (c1 > c2); |
| i1++; i2++; |
| /* 6 */ |
| c1 = block[i1]; c2 = block[i2]; |
| if (c1 != c2) return (c1 > c2); |
| i1++; i2++; |
| /* 7 */ |
| c1 = block[i1]; c2 = block[i2]; |
| if (c1 != c2) return (c1 > c2); |
| i1++; i2++; |
| /* 8 */ |
| c1 = block[i1]; c2 = block[i2]; |
| if (c1 != c2) return (c1 > c2); |
| i1++; i2++; |
| /* 9 */ |
| c1 = block[i1]; c2 = block[i2]; |
| if (c1 != c2) return (c1 > c2); |
| i1++; i2++; |
| /* 10 */ |
| c1 = block[i1]; c2 = block[i2]; |
| if (c1 != c2) return (c1 > c2); |
| i1++; i2++; |
| /* 11 */ |
| c1 = block[i1]; c2 = block[i2]; |
| if (c1 != c2) return (c1 > c2); |
| i1++; i2++; |
| /* 12 */ |
| c1 = block[i1]; c2 = block[i2]; |
| if (c1 != c2) return (c1 > c2); |
| i1++; i2++; |
| |
| k = nblock + 8; |
| |
| do { |
| /* 1 */ |
| c1 = block[i1]; c2 = block[i2]; |
| if (c1 != c2) return (c1 > c2); |
| s1 = quadrant[i1]; s2 = quadrant[i2]; |
| if (s1 != s2) return (s1 > s2); |
| i1++; i2++; |
| /* 2 */ |
| c1 = block[i1]; c2 = block[i2]; |
| if (c1 != c2) return (c1 > c2); |
| s1 = quadrant[i1]; s2 = quadrant[i2]; |
| if (s1 != s2) return (s1 > s2); |
| i1++; i2++; |
| /* 3 */ |
| c1 = block[i1]; c2 = block[i2]; |
| if (c1 != c2) return (c1 > c2); |
| s1 = quadrant[i1]; s2 = quadrant[i2]; |
| if (s1 != s2) return (s1 > s2); |
| i1++; i2++; |
| /* 4 */ |
| c1 = block[i1]; c2 = block[i2]; |
| if (c1 != c2) return (c1 > c2); |
| s1 = quadrant[i1]; s2 = quadrant[i2]; |
| if (s1 != s2) return (s1 > s2); |
| i1++; i2++; |
| /* 5 */ |
| c1 = block[i1]; c2 = block[i2]; |
| if (c1 != c2) return (c1 > c2); |
| s1 = quadrant[i1]; s2 = quadrant[i2]; |
| if (s1 != s2) return (s1 > s2); |
| i1++; i2++; |
| /* 6 */ |
| c1 = block[i1]; c2 = block[i2]; |
| if (c1 != c2) return (c1 > c2); |
| s1 = quadrant[i1]; s2 = quadrant[i2]; |
| if (s1 != s2) return (s1 > s2); |
| i1++; i2++; |
| /* 7 */ |
| c1 = block[i1]; c2 = block[i2]; |
| if (c1 != c2) return (c1 > c2); |
| s1 = quadrant[i1]; s2 = quadrant[i2]; |
| if (s1 != s2) return (s1 > s2); |
| i1++; i2++; |
| /* 8 */ |
| c1 = block[i1]; c2 = block[i2]; |
| if (c1 != c2) return (c1 > c2); |
| s1 = quadrant[i1]; s2 = quadrant[i2]; |
| if (s1 != s2) return (s1 > s2); |
| i1++; i2++; |
| |
| if (i1 >= nblock) i1 -= nblock; |
| if (i2 >= nblock) i2 -= nblock; |
| |
| k -= 8; |
| (*budget)--; |
| } |
| while (k >= 0); |
| |
| return False; |
| } |
| |
| |
| /*---------------------------------------------*/ |
| /*-- |
| Knuth's increments seem to work better |
| than Incerpi-Sedgewick here. Possibly |
| because the number of elems to sort is |
| usually small, typically <= 20. |
| --*/ |
| static |
| Int32 incs[14] = { 1, 4, 13, 40, 121, 364, 1093, 3280, |
| 9841, 29524, 88573, 265720, |
| 797161, 2391484 }; |
| |
| static |
| void mainSimpleSort ( UInt32* ptr, |
| UChar* block, |
| UInt16* quadrant, |
| Int32 nblock, |
| Int32 lo, |
| Int32 hi, |
| Int32 d, |
| Int32* budget ) |
| { |
| Int32 i, j, h, bigN, hp; |
| UInt32 v; |
| |
| bigN = hi - lo + 1; |
| if (bigN < 2) return; |
| |
| hp = 0; |
| while (incs[hp] < bigN) hp++; |
| hp--; |
| |
| for (; hp >= 0; hp--) { |
| h = incs[hp]; |
| |
| i = lo + h; |
| while (True) { |
| |
| /*-- copy 1 --*/ |
| if (i > hi) break; |
| v = ptr[i]; |
| j = i; |
| while ( mainGtU ( |
| ptr[j-h]+d, v+d, block, quadrant, nblock, budget |
| ) ) { |
| ptr[j] = ptr[j-h]; |
| j = j - h; |
| if (j <= (lo + h - 1)) break; |
| } |
| ptr[j] = v; |
| i++; |
| |
| /*-- copy 2 --*/ |
| if (i > hi) break; |
| v = ptr[i]; |
| j = i; |
| while ( mainGtU ( |
| ptr[j-h]+d, v+d, block, quadrant, nblock, budget |
| ) ) { |
| ptr[j] = ptr[j-h]; |
| j = j - h; |
| if (j <= (lo + h - 1)) break; |
| } |
| ptr[j] = v; |
| i++; |
| |
| /*-- copy 3 --*/ |
| if (i > hi) break; |
| v = ptr[i]; |
| j = i; |
| while ( mainGtU ( |
| ptr[j-h]+d, v+d, block, quadrant, nblock, budget |
| ) ) { |
| ptr[j] = ptr[j-h]; |
| j = j - h; |
| if (j <= (lo + h - 1)) break; |
| } |
| ptr[j] = v; |
| i++; |
| |
| if (*budget < 0) return; |
| } |
| } |
| } |
| |
| |
| /*---------------------------------------------*/ |
| /*-- |
| The following is an implementation of |
| an elegant 3-way quicksort for strings, |
| described in a paper "Fast Algorithms for |
| Sorting and Searching Strings", by Robert |
| Sedgewick and Jon L. Bentley. |
| --*/ |
| |
| #define mswap(zz1, zz2) \ |
| { Int32 zztmp = zz1; zz1 = zz2; zz2 = zztmp; } |
| |
| #define mvswap(zzp1, zzp2, zzn) \ |
| { \ |
| Int32 yyp1 = (zzp1); \ |
| Int32 yyp2 = (zzp2); \ |
| Int32 yyn = (zzn); \ |
| while (yyn > 0) { \ |
| mswap(ptr[yyp1], ptr[yyp2]); \ |
| yyp1++; yyp2++; yyn--; \ |
| } \ |
| } |
| |
| static |
| __inline__ |
| UChar mmed3 ( UChar a, UChar b, UChar c ) |
| { |
| UChar t; |
| if (a > b) { t = a; a = b; b = t; }; |
| if (b > c) { |
| b = c; |
| if (a > b) b = a; |
| } |
| return b; |
| } |
| |
| #define mmin(a,b) ((a) < (b)) ? (a) : (b) |
| |
| #define mpush(lz,hz,dz) { stackLo[sp] = lz; \ |
| stackHi[sp] = hz; \ |
| stackD [sp] = dz; \ |
| sp++; } |
| |
| #define mpop(lz,hz,dz) { sp--; \ |
| lz = stackLo[sp]; \ |
| hz = stackHi[sp]; \ |
| dz = stackD [sp]; } |
| |
| |
| #define mnextsize(az) (nextHi[az]-nextLo[az]) |
| |
| #define mnextswap(az,bz) \ |
| { Int32 tz; \ |
| tz = nextLo[az]; nextLo[az] = nextLo[bz]; nextLo[bz] = tz; \ |
| tz = nextHi[az]; nextHi[az] = nextHi[bz]; nextHi[bz] = tz; \ |
| tz = nextD [az]; nextD [az] = nextD [bz]; nextD [bz] = tz; } |
| |
| |
| #define MAIN_QSORT_SMALL_THRESH 20 |
| #define MAIN_QSORT_DEPTH_THRESH (BZ_N_RADIX + BZ_N_QSORT) |
| #define MAIN_QSORT_STACK_SIZE 100 |
| |
| static |
| void mainQSort3 ( UInt32* ptr, |
| UChar* block, |
| UInt16* quadrant, |
| Int32 nblock, |
| Int32 loSt, |
| Int32 hiSt, |
| Int32 dSt, |
| Int32* budget ) |
| { |
| Int32 unLo, unHi, ltLo, gtHi, n, m, med; |
| Int32 sp, lo, hi, d; |
| |
| Int32 stackLo[MAIN_QSORT_STACK_SIZE]; |
| Int32 stackHi[MAIN_QSORT_STACK_SIZE]; |
| Int32 stackD [MAIN_QSORT_STACK_SIZE]; |
| |
| Int32 nextLo[3]; |
| Int32 nextHi[3]; |
| Int32 nextD [3]; |
| |
| sp = 0; |
| mpush ( loSt, hiSt, dSt ); |
| |
| while (sp > 0) { |
| |
| AssertH ( sp < MAIN_QSORT_STACK_SIZE, 1001 ); |
| |
| mpop ( lo, hi, d ); |
| if (hi - lo < MAIN_QSORT_SMALL_THRESH || |
| d > MAIN_QSORT_DEPTH_THRESH) { |
| mainSimpleSort ( ptr, block, quadrant, nblock, lo, hi, d, budget ); |
| if (*budget < 0) return; |
| continue; |
| } |
| |
| med = (Int32) |
| mmed3 ( block[ptr[ lo ]+d], |
| block[ptr[ hi ]+d], |
| block[ptr[ (lo+hi)>>1 ]+d] ); |
| |
| unLo = ltLo = lo; |
| unHi = gtHi = hi; |
| |
| while (True) { |
| while (True) { |
| if (unLo > unHi) break; |
| n = ((Int32)block[ptr[unLo]+d]) - med; |
| if (n == 0) { |
| mswap(ptr[unLo], ptr[ltLo]); |
| ltLo++; unLo++; continue; |
| }; |
| if (n > 0) break; |
| unLo++; |
| } |
| while (True) { |
| if (unLo > unHi) break; |
| n = ((Int32)block[ptr[unHi]+d]) - med; |
| if (n == 0) { |
| mswap(ptr[unHi], ptr[gtHi]); |
| gtHi--; unHi--; continue; |
| }; |
| if (n < 0) break; |
| unHi--; |
| } |
| if (unLo > unHi) break; |
| mswap(ptr[unLo], ptr[unHi]); unLo++; unHi--; |
| } |
| |
| AssertD ( unHi == unLo-1, "mainQSort3(2)" ); |
| |
| if (gtHi < ltLo) { |
| mpush(lo, hi, d+1 ); |
| continue; |
| } |
| |
| n = mmin(ltLo-lo, unLo-ltLo); mvswap(lo, unLo-n, n); |
| m = mmin(hi-gtHi, gtHi-unHi); mvswap(unLo, hi-m+1, m); |
| |
| n = lo + unLo - ltLo - 1; |
| m = hi - (gtHi - unHi) + 1; |
| |
| nextLo[0] = lo; nextHi[0] = n; nextD[0] = d; |
| nextLo[1] = m; nextHi[1] = hi; nextD[1] = d; |
| nextLo[2] = n+1; nextHi[2] = m-1; nextD[2] = d+1; |
| |
| if (mnextsize(0) < mnextsize(1)) mnextswap(0,1); |
| if (mnextsize(1) < mnextsize(2)) mnextswap(1,2); |
| if (mnextsize(0) < mnextsize(1)) mnextswap(0,1); |
| |
| AssertD (mnextsize(0) >= mnextsize(1), "mainQSort3(8)" ); |
| AssertD (mnextsize(1) >= mnextsize(2), "mainQSort3(9)" ); |
| |
| mpush (nextLo[0], nextHi[0], nextD[0]); |
| mpush (nextLo[1], nextHi[1], nextD[1]); |
| mpush (nextLo[2], nextHi[2], nextD[2]); |
| } |
| } |
| |
| #undef mswap |
| #undef mvswap |
| #undef mpush |
| #undef mpop |
| #undef mmin |
| #undef mnextsize |
| #undef mnextswap |
| #undef MAIN_QSORT_SMALL_THRESH |
| #undef MAIN_QSORT_DEPTH_THRESH |
| #undef MAIN_QSORT_STACK_SIZE |
| |
| |
| /*---------------------------------------------*/ |
| /* Pre: |
| nblock > N_OVERSHOOT |
| block32 exists for [0 .. nblock-1 +N_OVERSHOOT] |
| ((UChar*)block32) [0 .. nblock-1] holds block |
| ptr exists for [0 .. nblock-1] |
| |
| Post: |
| ((UChar*)block32) [0 .. nblock-1] holds block |
| All other areas of block32 destroyed |
| ftab [0 .. 65536 ] destroyed |
| ptr [0 .. nblock-1] holds sorted order |
| if (*budget < 0), sorting was abandoned |
| */ |
| |
| #define BIGFREQ(b) (ftab[((b)+1) << 8] - ftab[(b) << 8]) |
| #define SETMASK (1 << 21) |
| #define CLEARMASK (~(SETMASK)) |
| |
| static |
| void mainSort ( UInt32* ptr, |
| UChar* block, |
| UInt16* quadrant, |
| UInt32* ftab, |
| Int32 nblock, |
| Int32 verb, |
| Int32* budget ) |
| { |
| Int32 i, j, k, ss, sb; |
| Int32 runningOrder[256]; |
| Bool bigDone[256]; |
| Int32 copyStart[256]; |
| Int32 copyEnd [256]; |
| UChar c1; |
| Int32 numQSorted; |
| UInt16 s; |
| if (verb >= 4) VPrintf0 ( " main sort initialise ...\n" ); |
| |
| /*-- set up the 2-byte frequency table --*/ |
| for (i = 65536; i >= 0; i--) ftab[i] = 0; |
| |
| j = block[0] << 8; |
| i = nblock-1; |
| for (; i >= 3; i -= 4) { |
| quadrant[i] = 0; |
| j = (j >> 8) | ( ((UInt16)block[i]) << 8); |
| ftab[j]++; |
| quadrant[i-1] = 0; |
| j = (j >> 8) | ( ((UInt16)block[i-1]) << 8); |
| ftab[j]++; |
| quadrant[i-2] = 0; |
| j = (j >> 8) | ( ((UInt16)block[i-2]) << 8); |
| ftab[j]++; |
| quadrant[i-3] = 0; |
| j = (j >> 8) | ( ((UInt16)block[i-3]) << 8); |
| ftab[j]++; |
| } |
| for (; i >= 0; i--) { |
| quadrant[i] = 0; |
| j = (j >> 8) | ( ((UInt16)block[i]) << 8); |
| ftab[j]++; |
| } |
| |
| /*-- (emphasises close relationship of block & quadrant) --*/ |
| for (i = 0; i < BZ_N_OVERSHOOT; i++) { |
| block [nblock+i] = block[i]; |
| quadrant[nblock+i] = 0; |
| } |
| |
| if (verb >= 4) VPrintf0 ( " bucket sorting ...\n" ); |
| |
| /*-- Complete the initial radix sort --*/ |
| for (i = 1; i <= 65536; i++) ftab[i] += ftab[i-1]; |
| |
| s = block[0] << 8; |
| i = nblock-1; |
| for (; i >= 3; i -= 4) { |
| s = (s >> 8) | (block[i] << 8); |
| j = ftab[s] -1; |
| ftab[s] = j; |
| ptr[j] = i; |
| s = (s >> 8) | (block[i-1] << 8); |
| j = ftab[s] -1; |
| ftab[s] = j; |
| ptr[j] = i-1; |
| s = (s >> 8) | (block[i-2] << 8); |
| j = ftab[s] -1; |
| ftab[s] = j; |
| ptr[j] = i-2; |
| s = (s >> 8) | (block[i-3] << 8); |
| j = ftab[s] -1; |
| ftab[s] = j; |
| ptr[j] = i-3; |
| } |
| for (; i >= 0; i--) { |
| s = (s >> 8) | (block[i] << 8); |
| j = ftab[s] -1; |
| ftab[s] = j; |
| ptr[j] = i; |
| } |
| |
| /*-- |
| Now ftab contains the first loc of every small bucket. |
| Calculate the running order, from smallest to largest |
| big bucket. |
| --*/ |
| for (i = 0; i <= 255; i++) { |
| bigDone [i] = False; |
| runningOrder[i] = i; |
| } |
| |
| { |
| Int32 vv; |
| Int32 h = 1; |
| do h = 3 * h + 1; while (h <= 256); |
| do { |
| h = h / 3; |
| for (i = h; i <= 255; i++) { |
| vv = runningOrder[i]; |
| j = i; |
| while ( BIGFREQ(runningOrder[j-h]) > BIGFREQ(vv) ) { |
| runningOrder[j] = runningOrder[j-h]; |
| j = j - h; |
| if (j <= (h - 1)) goto zero; |
| } |
| zero: |
| runningOrder[j] = vv; |
| } |
| } while (h != 1); |
| } |
| |
| /*-- |
| The main sorting loop. |
| --*/ |
| |
| numQSorted = 0; |
| |
| for (i = 0; i <= 255; i++) { |
| |
| /*-- |
| Process big buckets, starting with the least full. |
| Basically this is a 3-step process in which we call |
| mainQSort3 to sort the small buckets [ss, j], but |
| also make a big effort to avoid the calls if we can. |
| --*/ |
| ss = runningOrder[i]; |
| |
| /*-- |
| Step 1: |
| Complete the big bucket [ss] by quicksorting |
| any unsorted small buckets [ss, j], for j != ss. |
| Hopefully previous pointer-scanning phases have already |
| completed many of the small buckets [ss, j], so |
| we don't have to sort them at all. |
| --*/ |
| for (j = 0; j <= 255; j++) { |
| if (j != ss) { |
| sb = (ss << 8) + j; |
| if ( ! (ftab[sb] & SETMASK) ) { |
| Int32 lo = ftab[sb] & CLEARMASK; |
| Int32 hi = (ftab[sb+1] & CLEARMASK) - 1; |
| if (hi > lo) { |
| if (verb >= 4) |
| VPrintf4 ( " qsort [0x%x, 0x%x] " |
| "done %d this %d\n", |
| ss, j, numQSorted, hi - lo + 1 ); |
| mainQSort3 ( |
| ptr, block, quadrant, nblock, |
| lo, hi, BZ_N_RADIX, budget |
| ); |
| numQSorted += (hi - lo + 1); |
| if (*budget < 0) return; |
| } |
| } |
| ftab[sb] |= SETMASK; |
| } |
| } |
| |
| AssertH ( !bigDone[ss], 1006 ); |
| |
| /*-- |
| Step 2: |
| Now scan this big bucket [ss] so as to synthesise the |
| sorted order for small buckets [t, ss] for all t, |
| including, magically, the bucket [ss,ss] too. |
| This will avoid doing Real Work in subsequent Step 1's. |
| --*/ |
| { |
| for (j = 0; j <= 255; j++) { |
| copyStart[j] = ftab[(j << 8) + ss] & CLEARMASK; |
| copyEnd [j] = (ftab[(j << 8) + ss + 1] & CLEARMASK) - 1; |
| } |
| for (j = ftab[ss << 8] & CLEARMASK; j < copyStart[ss]; j++) { |
| k = ptr[j]-1; if (k < 0) k += nblock; |
| c1 = block[k]; |
| if (!bigDone[c1]) |
| ptr[ copyStart[c1]++ ] = k; |
| } |
| for (j = (ftab[(ss+1) << 8] & CLEARMASK) - 1; j > copyEnd[ss]; j--) { |
| k = ptr[j]-1; if (k < 0) k += nblock; |
| c1 = block[k]; |
| if (!bigDone[c1]) |
| ptr[ copyEnd[c1]-- ] = k; |
| } |
| } |
| |
| AssertH ( copyStart[ss]-1 == copyEnd[ss], 1007 ); |
| |
| for (j = 0; j <= 255; j++) ftab[(j << 8) + ss] |= SETMASK; |
| |
| /*-- |
| Step 3: |
| The [ss] big bucket is now done. Record this fact, |
| and update the quadrant descriptors. Remember to |
| update quadrants in the overshoot area too, if |
| necessary. The "if (i < 255)" test merely skips |
| this updating for the last bucket processed, since |
| updating for the last bucket is pointless. |
| |
| The quadrant array provides a way to incrementally |
| cache sort orderings, as they appear, so as to |
| make subsequent comparisons in fullGtU() complete |
| faster. For repetitive blocks this makes a big |
| difference (but not big enough to be able to avoid |
| the fallback sorting mechanism, exponential radix sort). |
| |
| The precise meaning is: at all times: |
| |
| for 0 <= i < nblock and 0 <= j <= nblock |
| |
| if block[i] != block[j], |
| |
| then the relative values of quadrant[i] and |
| quadrant[j] are meaningless. |
| |
| else { |
| if quadrant[i] < quadrant[j] |
| then the string starting at i lexicographically |
| precedes the string starting at j |
| |
| else if quadrant[i] > quadrant[j] |
| then the string starting at j lexicographically |
| precedes the string starting at i |
| |
| else |
| the relative ordering of the strings starting |
| at i and j has not yet been determined. |
| } |
| --*/ |
| bigDone[ss] = True; |
| |
| if (i < 255) { |
| Int32 bbStart = ftab[ss << 8] & CLEARMASK; |
| Int32 bbSize = (ftab[(ss+1) << 8] & CLEARMASK) - bbStart; |
| Int32 shifts = 0; |
| |
| while ((bbSize >> shifts) > 65534) shifts++; |
| |
| for (j = bbSize-1; j >= 0; j--) { |
| Int32 a2update = ptr[bbStart + j]; |
| UInt16 qVal = (UInt16)(j >> shifts); |
| quadrant[a2update] = qVal; |
| if (a2update < BZ_N_OVERSHOOT) |
| quadrant[a2update + nblock] = qVal; |
| } |
| AssertH ( ((bbSize-1) >> shifts) <= 65535, 1002 ); |
| } |
| |
| } |
| |
| if (verb >= 4) |
| VPrintf3 ( " %d pointers, %d sorted, %d scanned\n", |
| nblock, numQSorted, nblock - numQSorted ); |
| } |
| |
| #undef BIGFREQ |
| #undef SETMASK |
| #undef CLEARMASK |
| |
| |
| /*---------------------------------------------*/ |
| /* Pre: |
| nblock > 0 |
| arr2 exists for [0 .. nblock-1 +N_OVERSHOOT] |
| ((UChar*)arr2) [0 .. nblock-1] holds block |
| arr1 exists for [0 .. nblock-1] |
| |
| Post: |
| ((UChar*)arr2) [0 .. nblock-1] holds block |
| All other areas of block destroyed |
| ftab [ 0 .. 65536 ] destroyed |
| arr1 [0 .. nblock-1] holds sorted order |
| */ |
| void BZ2_blockSort ( EState* s ) |
| { |
| UInt32* ptr = s->ptr; |
| UChar* block = s->block; |
| UInt32* ftab = s->ftab; |
| Int32 nblock = s->nblock; |
| Int32 verb = s->verbosity; |
| Int32 wfact = s->workFactor; |
| UInt16* quadrant; |
| Int32 budget; |
| Int32 budgetInit; |
| Int32 i; |
| |
| if (nblock < 10000) { |
| fallbackSort ( s->arr1, s->arr2, ftab, nblock, verb ); |
| } else { |
| /* Calculate the location for quadrant, remembering to get |
| the alignment right. Assumes that &(block[0]) is at least |
| 2-byte aligned -- this should be ok since block is really |
| the first section of arr2. |
| */ |
| i = nblock+BZ_N_OVERSHOOT; |
| if (i & 1) i++; |
| quadrant = (UInt16*)(&(block[i])); |
| |
| /* (wfact-1) / 3 puts the default-factor-30 |
| transition point at very roughly the same place as |
| with v0.1 and v0.9.0. |
| Not that it particularly matters any more, since the |
| resulting compressed stream is now the same regardless |
| of whether or not we use the main sort or fallback sort. |
| */ |
| if (wfact < 1 ) wfact = 1; |
| if (wfact > 100) wfact = 100; |
| budgetInit = nblock * ((wfact-1) / 3); |
| budget = budgetInit; |
| |
| mainSort ( ptr, block, quadrant, ftab, nblock, verb, &budget ); |
| if (verb >= 3) |
| VPrintf3 ( " %d work, %d block, ratio %5.2f\n", |
| budgetInit - budget, |
| nblock, |
| (float)(budgetInit - budget) / |
| (float)(nblock==0 ? 1 : nblock) ); |
| if (budget < 0) { |
| if (verb >= 2) |
| VPrintf0 ( " too repetitive; using fallback" |
| " sorting algorithm\n" ); |
| fallbackSort ( s->arr1, s->arr2, ftab, nblock, verb ); |
| } |
| } |
| |
| s->origPtr = -1; |
| for (i = 0; i < s->nblock; i++) |
| if (ptr[i] == 0) |
| { s->origPtr = i; break; }; |
| |
| AssertH( s->origPtr != -1, 1003 ); |
| } |
| |
| |
| /*-------------------------------------------------------------*/ |
| /*--- end blocksort.c ---*/ |
| /*-------------------------------------------------------------*/ |
