// This may look like C code, but it is really -*- C++ -*- /* Copyright (C) 1988 Free Software Foundation written by Doug Lea (dl@rocky.oswego.edu) This file is part of GNU CC. GNU CC is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY. No author or distributor accepts responsibility to anyone for the consequences of using it or for whether it serves any particular purpose or works at all, unless he says so in writing. Refer to the GNU CC General Public License for full details. Everyone is granted permission to copy, modify and redistribute GNU CC, but only under the conditions described in the GNU CC General Public License. A copy of this license is supposed to have been given to you along with GNU CC so you can know your rights and responsibilities. It should be in a file named COPYING. Among other things, the copyright notice and this notice must be preserved on all copies. */ #ifdef __GNUG__ #pragma implementation #endif #include ".OXPSet.h" Pix OXPSet::seek( item) { int l = p.low(); int h = p.high(); while (l <= h) { int mid = (l + h) / 2; int cmp = CMP(item, p[mid]); if (cmp == 0) return p.index_to_Pix(mid); else if (cmp < 0) h = mid - 1; else l = mid + 1; } return 0; } Pix OXPSet::add( item) { if (count == 0) { ++count; return p.index_to_Pix(p.add_high(item)); } int l = p.low(); int h = p.high(); while (l <= h) { int mid = (l + h) / 2; int cmp = CMP(item, p[mid]); if (cmp == 0) return p.index_to_Pix(mid); else if (cmp < 0) h = mid - 1; else l = mid + 1; } // add on whichever side is shortest ++count; if (l == p.fence()) return p.index_to_Pix(p.add_high(item)); else if (l == p.low()) return p.index_to_Pix(p.add_low(item)); else { if (p.fence() - l < l - p.low()) { h = p.add_high(p.high_element()); for (int i = h - 1; i > l; --i) p[i] = p[i-1]; } else { --l; h = p.add_low(p.low_element()); for (int i = h + 1; i < l; ++i) p[i] = p[i+1]; } p[l] = item; return p.index_to_Pix(l); } } void OXPSet::del( item) { int l = p.low(); int h = p.high(); while (l <= h) { int mid = (l + h) / 2; int cmp = CMP(item, p[mid]); if (cmp == 0) { --count; if (p.high() - mid < mid - p.low()) { for (int i = mid; i < p.high(); ++i) p[i] = p[i+1]; p.del_high(); } else { for (int i = mid; i > p.low(); --i) p[i] = p[i-1]; p.del_low(); } return; } else if (cmp < 0) h = mid - 1; else l = mid + 1; } } int OXPSet::operator <= (OXPSet& b) { if (count > b.count) return 0; int i = p.low(); int j = b.p.low(); for (;;) { if (i >= p.fence()) return 1; else if (j >= b.p.fence()) return 0; int cmp = CMP(p[i], b.p[j]); if (cmp == 0) { ++i; ++j; } else if (cmp < 0) return 0; else ++j; } } int OXPSet::operator == (OXPSet& b) { int n = count; if (n != b.count) return 0; if (n == 0) return 1; int i = p.low(); int j = b.p.low(); while (n-- > 0) if (!EQ(p[i++], b.p[j++])) return 0; return 1; } void OXPSet::operator |= (OXPSet& b) { if (&b == this || b.count == 0) return; else if (b.count <= 2) // small b -- just add for (Pix i = b.first(); i; b.next(i)) add(b(i)); else { // strategy: merge into top of p, simultaneously killing old bottom int oldfence = p.fence(); int i = p.low(); int j = b.p.low(); for (;;) { if (i == oldfence) { while (j < b.p.fence()) p.add_high(b.p[j++]); break; } else if (j == b.p.fence()) { while (i++ < oldfence) { p.add_high(p.low_element()); p.del_low(); } break; } int cmp = CMP(p[i], b.p[j]); if (cmp <= 0) { ++i; if (cmp == 0) ++j; p.add_high(p.low_element()); p.del_low(); } else p.add_high(b.p[j++]); } count = p.length(); } } void OXPSet::operator -= (OXPSet& b) { if (&b == this) clear(); else if (count != 0 && b.count != 0) { int i = p.low(); int k = i; int j = b.p.low(); int oldfence = p.fence(); for (;;) { if (i >= oldfence) break; else if (j >= b.p.fence()) { if (k != i) while (i < oldfence) p[k++] = p[i++]; else k = oldfence; break; } int cmp = CMP(p[i], b.p[j]); if (cmp == 0) { ++i; ++j; } else if (cmp < 0) { if (k != i) p[k] = p[i]; ++i; ++k; } else j++; } while (k++ < oldfence) { --count; p.del_high(); } } } void OXPSet::operator &= (OXPSet& b) { if (b.count == 0) clear(); else if (&b != this && count != 0) { int i = p.low(); int k = i; int j = b.p.low(); int oldfence = p.fence(); for (;;) { if (i >= oldfence || j >= b.p.fence()) break; int cmp = CMP(p[i], b.p[j]); if (cmp == 0) { if (k != i) p[k] = p[i]; ++i; ++k; ++j; } else if (cmp < 0) ++i; else ++j; } while (k++ < oldfence) { --count; p.del_high(); } } } int OXPSet::OK() { int v = p.OK(); v &= count == p.length(); for (int i = p.low(); i < p.high(); ++i) v &= CMP(p[i], p[i+1]) < 0; if (!v) error("invariant failure"); return v; }