| // Inferno's libkern/vlrt-386.c |
| // http://code.google.com/p/inferno-os/source/browse/libkern/vlrt-386.c |
| // |
| // Copyright © 1994-1999 Lucent Technologies Inc. All rights reserved. |
| // Revisions Copyright © 2000-2007 Vita Nuova Holdings Limited (www.vitanuova.com). All rights reserved. |
| // Portions Copyright 2009 The Go Authors. All rights reserved. |
| // |
| // Permission is hereby granted, free of charge, to any person obtaining a copy |
| // of this software and associated documentation files (the "Software"), to deal |
| // in the Software without restriction, including without limitation the rights |
| // to use, copy, modify, merge, publish, distribute, sublicense, and/or sell |
| // copies of the Software, and to permit persons to whom the Software is |
| // furnished to do so, subject to the following conditions: |
| // |
| // The above copyright notice and this permission notice shall be included in |
| // all copies or substantial portions of the Software. |
| // |
| // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR |
| // IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, |
| // FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE |
| // AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER |
| // LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, |
| // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN |
| // THE SOFTWARE. |
| |
| /* |
| * C runtime for 64-bit divide, others. |
| * |
| * TODO(rsc): The simple functions are dregs--8c knows how |
| * to generate the code directly now. Find and remove. |
| */ |
| |
| typedef unsigned long ulong; |
| typedef unsigned int uint; |
| typedef unsigned short ushort; |
| typedef unsigned char uchar; |
| typedef signed char schar; |
| |
| #define SIGN(n) (1UL<<(n-1)) |
| |
| typedef struct Vlong Vlong; |
| struct Vlong |
| { |
| union |
| { |
| long long v; |
| struct |
| { |
| ulong lo; |
| ulong hi; |
| }; |
| struct |
| { |
| ushort lols; |
| ushort loms; |
| ushort hils; |
| ushort hims; |
| }; |
| }; |
| }; |
| |
| void abort(void); |
| |
| void |
| _d2v(Vlong *y, double d) |
| { |
| union { double d; struct Vlong; } x; |
| ulong xhi, xlo, ylo, yhi; |
| int sh; |
| |
| x.d = d; |
| |
| xhi = (x.hi & 0xfffff) | 0x100000; |
| xlo = x.lo; |
| sh = 1075 - ((x.hi >> 20) & 0x7ff); |
| |
| ylo = 0; |
| yhi = 0; |
| if(sh >= 0) { |
| /* v = (hi||lo) >> sh */ |
| if(sh < 32) { |
| if(sh == 0) { |
| ylo = xlo; |
| yhi = xhi; |
| } else { |
| ylo = (xlo >> sh) | (xhi << (32-sh)); |
| yhi = xhi >> sh; |
| } |
| } else { |
| if(sh == 32) { |
| ylo = xhi; |
| } else |
| if(sh < 64) { |
| ylo = xhi >> (sh-32); |
| } |
| } |
| } else { |
| /* v = (hi||lo) << -sh */ |
| sh = -sh; |
| if(sh <= 10) { |
| ylo = xlo << sh; |
| yhi = (xhi << sh) | (xlo >> (32-sh)); |
| } else { |
| /* overflow */ |
| yhi = d; /* causes something awful */ |
| } |
| } |
| if(x.hi & SIGN(32)) { |
| if(ylo != 0) { |
| ylo = -ylo; |
| yhi = ~yhi; |
| } else |
| yhi = -yhi; |
| } |
| |
| y->hi = yhi; |
| y->lo = ylo; |
| } |
| |
| void |
| _f2v(Vlong *y, float f) |
| { |
| |
| _d2v(y, f); |
| } |
| |
| double |
| _v2d(Vlong x) |
| { |
| if(x.hi & SIGN(32)) { |
| if(x.lo) { |
| x.lo = -x.lo; |
| x.hi = ~x.hi; |
| } else |
| x.hi = -x.hi; |
| return -((long)x.hi*4294967296. + x.lo); |
| } |
| return (long)x.hi*4294967296. + x.lo; |
| } |
| |
| float |
| _v2f(Vlong x) |
| { |
| return _v2d(x); |
| } |
| |
| ulong _div64by32(Vlong, ulong, ulong*); |
| void _mul64by32(Vlong*, Vlong, ulong); |
| |
| static void |
| slowdodiv(Vlong num, Vlong den, Vlong *q, Vlong *r) |
| { |
| ulong numlo, numhi, denhi, denlo, quohi, quolo, t; |
| int i; |
| |
| numhi = num.hi; |
| numlo = num.lo; |
| denhi = den.hi; |
| denlo = den.lo; |
| |
| /* |
| * get a divide by zero |
| */ |
| if(denlo==0 && denhi==0) { |
| numlo = numlo / denlo; |
| } |
| |
| /* |
| * set up the divisor and find the number of iterations needed |
| */ |
| if(numhi >= SIGN(32)) { |
| quohi = SIGN(32); |
| quolo = 0; |
| } else { |
| quohi = numhi; |
| quolo = numlo; |
| } |
| i = 0; |
| while(denhi < quohi || (denhi == quohi && denlo < quolo)) { |
| denhi = (denhi<<1) | (denlo>>31); |
| denlo <<= 1; |
| i++; |
| } |
| |
| quohi = 0; |
| quolo = 0; |
| for(; i >= 0; i--) { |
| quohi = (quohi<<1) | (quolo>>31); |
| quolo <<= 1; |
| if(numhi > denhi || (numhi == denhi && numlo >= denlo)) { |
| t = numlo; |
| numlo -= denlo; |
| if(numlo > t) |
| numhi--; |
| numhi -= denhi; |
| quolo |= 1; |
| } |
| denlo = (denlo>>1) | (denhi<<31); |
| denhi >>= 1; |
| } |
| |
| if(q) { |
| q->lo = quolo; |
| q->hi = quohi; |
| } |
| if(r) { |
| r->lo = numlo; |
| r->hi = numhi; |
| } |
| } |
| |
| static void |
| dodiv(Vlong num, Vlong den, Vlong *qp, Vlong *rp) |
| { |
| ulong n; |
| Vlong x, q, r; |
| |
| if(den.hi > num.hi || (den.hi == num.hi && den.lo > num.lo)){ |
| if(qp) { |
| qp->hi = 0; |
| qp->lo = 0; |
| } |
| if(rp) { |
| rp->hi = num.hi; |
| rp->lo = num.lo; |
| } |
| return; |
| } |
| |
| if(den.hi != 0){ |
| q.hi = 0; |
| n = num.hi/den.hi; |
| _mul64by32(&x, den, n); |
| if(x.hi > num.hi || (x.hi == num.hi && x.lo > num.lo)) |
| slowdodiv(num, den, &q, &r); |
| else { |
| q.lo = n; |
| r.v = num.v - x.v; |
| } |
| } else { |
| if(num.hi >= den.lo){ |
| q.hi = n = num.hi/den.lo; |
| num.hi -= den.lo*n; |
| } else { |
| q.hi = 0; |
| } |
| q.lo = _div64by32(num, den.lo, &r.lo); |
| r.hi = 0; |
| } |
| if(qp) { |
| qp->lo = q.lo; |
| qp->hi = q.hi; |
| } |
| if(rp) { |
| rp->lo = r.lo; |
| rp->hi = r.hi; |
| } |
| } |
| |
| void |
| _divvu(Vlong *q, Vlong n, Vlong d) |
| { |
| |
| if(n.hi == 0 && d.hi == 0) { |
| q->hi = 0; |
| q->lo = n.lo / d.lo; |
| return; |
| } |
| dodiv(n, d, q, 0); |
| } |
| |
| void |
| sys·uint64div(Vlong n, Vlong d, Vlong q) |
| { |
| _divvu(&q, n, d); |
| } |
| |
| void |
| _modvu(Vlong *r, Vlong n, Vlong d) |
| { |
| |
| if(n.hi == 0 && d.hi == 0) { |
| r->hi = 0; |
| r->lo = n.lo % d.lo; |
| return; |
| } |
| dodiv(n, d, 0, r); |
| } |
| |
| void |
| sys·uint64mod(Vlong n, Vlong d, Vlong q) |
| { |
| _modvu(&q, n, d); |
| } |
| |
| static void |
| vneg(Vlong *v) |
| { |
| |
| if(v->lo == 0) { |
| v->hi = -v->hi; |
| return; |
| } |
| v->lo = -v->lo; |
| v->hi = ~v->hi; |
| } |
| |
| void |
| _divv(Vlong *q, Vlong n, Vlong d) |
| { |
| long nneg, dneg; |
| |
| if(n.hi == (((long)n.lo)>>31) && d.hi == (((long)d.lo)>>31)) { |
| if((long)n.lo == -0x80000000 && (long)d.lo == -1) { |
| // special case: 32-bit -0x80000000 / -1 causes divide error, |
| // but it's okay in this 64-bit context. |
| q->lo = 0x80000000; |
| q->hi = 0; |
| return; |
| } |
| q->lo = (long)n.lo / (long)d.lo; |
| q->hi = ((long)q->lo) >> 31; |
| return; |
| } |
| nneg = n.hi >> 31; |
| if(nneg) |
| vneg(&n); |
| dneg = d.hi >> 31; |
| if(dneg) |
| vneg(&d); |
| dodiv(n, d, q, 0); |
| if(nneg != dneg) |
| vneg(q); |
| } |
| |
| void |
| sys·int64div(Vlong n, Vlong d, Vlong q) |
| { |
| _divv(&q, n, d); |
| } |
| |
| void |
| _modv(Vlong *r, Vlong n, Vlong d) |
| { |
| long nneg, dneg; |
| |
| if(n.hi == (((long)n.lo)>>31) && d.hi == (((long)d.lo)>>31)) { |
| if((long)n.lo == -0x80000000 && (long)d.lo == -1) { |
| // special case: 32-bit -0x80000000 % -1 causes divide error, |
| // but it's okay in this 64-bit context. |
| r->lo = 0; |
| r->hi = 0; |
| return; |
| } |
| r->lo = (long)n.lo % (long)d.lo; |
| r->hi = ((long)r->lo) >> 31; |
| return; |
| } |
| nneg = n.hi >> 31; |
| if(nneg) |
| vneg(&n); |
| dneg = d.hi >> 31; |
| if(dneg) |
| vneg(&d); |
| dodiv(n, d, 0, r); |
| if(nneg) |
| vneg(r); |
| } |
| |
| void |
| sys·int64mod(Vlong n, Vlong d, Vlong q) |
| { |
| _modv(&q, n, d); |
| } |
| |
| void |
| _rshav(Vlong *r, Vlong a, int b) |
| { |
| long t; |
| |
| t = a.hi; |
| if(b >= 32) { |
| r->hi = t>>31; |
| if(b >= 64) { |
| /* this is illegal re C standard */ |
| r->lo = t>>31; |
| return; |
| } |
| r->lo = t >> (b-32); |
| return; |
| } |
| if(b <= 0) { |
| r->hi = t; |
| r->lo = a.lo; |
| return; |
| } |
| r->hi = t >> b; |
| r->lo = (t << (32-b)) | (a.lo >> b); |
| } |
| |
| void |
| _rshlv(Vlong *r, Vlong a, int b) |
| { |
| ulong t; |
| |
| t = a.hi; |
| if(b >= 32) { |
| r->hi = 0; |
| if(b >= 64) { |
| /* this is illegal re C standard */ |
| r->lo = 0; |
| return; |
| } |
| r->lo = t >> (b-32); |
| return; |
| } |
| if(b <= 0) { |
| r->hi = t; |
| r->lo = a.lo; |
| return; |
| } |
| r->hi = t >> b; |
| r->lo = (t << (32-b)) | (a.lo >> b); |
| } |
| |
| void |
| _lshv(Vlong *r, Vlong a, int b) |
| { |
| ulong t; |
| |
| t = a.lo; |
| if(b >= 32) { |
| r->lo = 0; |
| if(b >= 64) { |
| /* this is illegal re C standard */ |
| r->hi = 0; |
| return; |
| } |
| r->hi = t << (b-32); |
| return; |
| } |
| if(b <= 0) { |
| r->lo = t; |
| r->hi = a.hi; |
| return; |
| } |
| r->lo = t << b; |
| r->hi = (t >> (32-b)) | (a.hi << b); |
| } |
| |
| void |
| _andv(Vlong *r, Vlong a, Vlong b) |
| { |
| r->hi = a.hi & b.hi; |
| r->lo = a.lo & b.lo; |
| } |
| |
| void |
| _orv(Vlong *r, Vlong a, Vlong b) |
| { |
| r->hi = a.hi | b.hi; |
| r->lo = a.lo | b.lo; |
| } |
| |
| void |
| _xorv(Vlong *r, Vlong a, Vlong b) |
| { |
| r->hi = a.hi ^ b.hi; |
| r->lo = a.lo ^ b.lo; |
| } |
| |
| void |
| _vpp(Vlong *l, Vlong *r) |
| { |
| |
| l->hi = r->hi; |
| l->lo = r->lo; |
| r->lo++; |
| if(r->lo == 0) |
| r->hi++; |
| } |
| |
| void |
| _vmm(Vlong *l, Vlong *r) |
| { |
| |
| l->hi = r->hi; |
| l->lo = r->lo; |
| if(r->lo == 0) |
| r->hi--; |
| r->lo--; |
| } |
| |
| void |
| _ppv(Vlong *l, Vlong *r) |
| { |
| |
| r->lo++; |
| if(r->lo == 0) |
| r->hi++; |
| l->hi = r->hi; |
| l->lo = r->lo; |
| } |
| |
| void |
| _mmv(Vlong *l, Vlong *r) |
| { |
| |
| if(r->lo == 0) |
| r->hi--; |
| r->lo--; |
| l->hi = r->hi; |
| l->lo = r->lo; |
| } |
| |
| void |
| _vasop(Vlong *ret, void *lv, void fn(Vlong*, Vlong, Vlong), int type, Vlong rv) |
| { |
| Vlong t, u; |
| |
| u.lo = 0; |
| u.hi = 0; |
| switch(type) { |
| default: |
| abort(); |
| break; |
| |
| case 1: /* schar */ |
| t.lo = *(schar*)lv; |
| t.hi = t.lo >> 31; |
| fn(&u, t, rv); |
| *(schar*)lv = u.lo; |
| break; |
| |
| case 2: /* uchar */ |
| t.lo = *(uchar*)lv; |
| t.hi = 0; |
| fn(&u, t, rv); |
| *(uchar*)lv = u.lo; |
| break; |
| |
| case 3: /* short */ |
| t.lo = *(short*)lv; |
| t.hi = t.lo >> 31; |
| fn(&u, t, rv); |
| *(short*)lv = u.lo; |
| break; |
| |
| case 4: /* ushort */ |
| t.lo = *(ushort*)lv; |
| t.hi = 0; |
| fn(&u, t, rv); |
| *(ushort*)lv = u.lo; |
| break; |
| |
| case 9: /* int */ |
| t.lo = *(int*)lv; |
| t.hi = t.lo >> 31; |
| fn(&u, t, rv); |
| *(int*)lv = u.lo; |
| break; |
| |
| case 10: /* uint */ |
| t.lo = *(uint*)lv; |
| t.hi = 0; |
| fn(&u, t, rv); |
| *(uint*)lv = u.lo; |
| break; |
| |
| case 5: /* long */ |
| t.lo = *(long*)lv; |
| t.hi = t.lo >> 31; |
| fn(&u, t, rv); |
| *(long*)lv = u.lo; |
| break; |
| |
| case 6: /* ulong */ |
| t.lo = *(ulong*)lv; |
| t.hi = 0; |
| fn(&u, t, rv); |
| *(ulong*)lv = u.lo; |
| break; |
| |
| case 7: /* vlong */ |
| case 8: /* uvlong */ |
| fn(&u, *(Vlong*)lv, rv); |
| *(Vlong*)lv = u; |
| break; |
| } |
| *ret = u; |
| } |
| |
| void |
| _p2v(Vlong *ret, void *p) |
| { |
| long t; |
| |
| t = (ulong)p; |
| ret->lo = t; |
| ret->hi = 0; |
| } |
| |
| void |
| _sl2v(Vlong *ret, long sl) |
| { |
| long t; |
| |
| t = sl; |
| ret->lo = t; |
| ret->hi = t >> 31; |
| } |
| |
| void |
| _ul2v(Vlong *ret, ulong ul) |
| { |
| long t; |
| |
| t = ul; |
| ret->lo = t; |
| ret->hi = 0; |
| } |
| |
| void |
| _si2v(Vlong *ret, int si) |
| { |
| long t; |
| |
| t = si; |
| ret->lo = t; |
| ret->hi = t >> 31; |
| } |
| |
| void |
| _ui2v(Vlong *ret, uint ui) |
| { |
| long t; |
| |
| t = ui; |
| ret->lo = t; |
| ret->hi = 0; |
| } |
| |
| void |
| _sh2v(Vlong *ret, long sh) |
| { |
| long t; |
| |
| t = (sh << 16) >> 16; |
| ret->lo = t; |
| ret->hi = t >> 31; |
| } |
| |
| void |
| _uh2v(Vlong *ret, ulong ul) |
| { |
| long t; |
| |
| t = ul & 0xffff; |
| ret->lo = t; |
| ret->hi = 0; |
| } |
| |
| void |
| _sc2v(Vlong *ret, long uc) |
| { |
| long t; |
| |
| t = (uc << 24) >> 24; |
| ret->lo = t; |
| ret->hi = t >> 31; |
| } |
| |
| void |
| _uc2v(Vlong *ret, ulong ul) |
| { |
| long t; |
| |
| t = ul & 0xff; |
| ret->lo = t; |
| ret->hi = 0; |
| } |
| |
| long |
| _v2sc(Vlong rv) |
| { |
| long t; |
| |
| t = rv.lo & 0xff; |
| return (t << 24) >> 24; |
| } |
| |
| long |
| _v2uc(Vlong rv) |
| { |
| |
| return rv.lo & 0xff; |
| } |
| |
| long |
| _v2sh(Vlong rv) |
| { |
| long t; |
| |
| t = rv.lo & 0xffff; |
| return (t << 16) >> 16; |
| } |
| |
| long |
| _v2uh(Vlong rv) |
| { |
| |
| return rv.lo & 0xffff; |
| } |
| |
| long |
| _v2sl(Vlong rv) |
| { |
| |
| return rv.lo; |
| } |
| |
| long |
| _v2ul(Vlong rv) |
| { |
| |
| return rv.lo; |
| } |
| |
| long |
| _v2si(Vlong rv) |
| { |
| |
| return rv.lo; |
| } |
| |
| long |
| _v2ui(Vlong rv) |
| { |
| |
| return rv.lo; |
| } |
| |
| int |
| _testv(Vlong rv) |
| { |
| return rv.lo || rv.hi; |
| } |
| |
| int |
| _eqv(Vlong lv, Vlong rv) |
| { |
| return lv.lo == rv.lo && lv.hi == rv.hi; |
| } |
| |
| int |
| _nev(Vlong lv, Vlong rv) |
| { |
| return lv.lo != rv.lo || lv.hi != rv.hi; |
| } |
| |
| int |
| _ltv(Vlong lv, Vlong rv) |
| { |
| return (long)lv.hi < (long)rv.hi || |
| (lv.hi == rv.hi && lv.lo < rv.lo); |
| } |
| |
| int |
| _lev(Vlong lv, Vlong rv) |
| { |
| return (long)lv.hi < (long)rv.hi || |
| (lv.hi == rv.hi && lv.lo <= rv.lo); |
| } |
| |
| int |
| _gtv(Vlong lv, Vlong rv) |
| { |
| return (long)lv.hi > (long)rv.hi || |
| (lv.hi == rv.hi && lv.lo > rv.lo); |
| } |
| |
| int |
| _gev(Vlong lv, Vlong rv) |
| { |
| return (long)lv.hi > (long)rv.hi || |
| (lv.hi == rv.hi && lv.lo >= rv.lo); |
| } |
| |
| int |
| _lov(Vlong lv, Vlong rv) |
| { |
| return lv.hi < rv.hi || |
| (lv.hi == rv.hi && lv.lo < rv.lo); |
| } |
| |
| int |
| _lsv(Vlong lv, Vlong rv) |
| { |
| return lv.hi < rv.hi || |
| (lv.hi == rv.hi && lv.lo <= rv.lo); |
| } |
| |
| int |
| _hiv(Vlong lv, Vlong rv) |
| { |
| return lv.hi > rv.hi || |
| (lv.hi == rv.hi && lv.lo > rv.lo); |
| } |
| |
| int |
| _hsv(Vlong lv, Vlong rv) |
| { |
| return lv.hi > rv.hi || |
| (lv.hi == rv.hi && lv.lo >= rv.lo); |
| } |