static int euclid(_MIPD_ big x,int num) { /* outputs next c.f. quotient from gcd(w5,w6) */ mr_small sr,m; #ifdef MR_FP mr_small dres; #endif mr_small lr,lq; big t; #ifndef MR_GENERIC_MT miracl *mr_mip=get_mip(); #endif if (num==0) { mr_mip->oldn=(-1); mr_mip->carryon=FALSE; mr_mip->last=FALSE; if (compare(mr_mip->w6,mr_mip->w5)>0) { /* ensure w5>w6 */ t=mr_mip->w5,mr_mip->w5=mr_mip->w6,mr_mip->w6=t; return (mr_mip->q=0); } } else if (num==mr_mip->oldn || mr_mip->q<0) return mr_mip->q; mr_mip->oldn=num; if (mr_mip->carryon) goto middle; start: if (size(mr_mip->w6)==0) return (mr_mip->q=(-1)); mr_mip->ndig=(int)mr_mip->w5->len; mr_mip->carryon=TRUE; mr_mip->a=1; mr_mip->b=0; mr_mip->c=0; mr_mip->d=1; if (mr_mip->ndig==1) { mr_mip->last=TRUE; mr_mip->u=mr_mip->w5->w[0]; mr_mip->v=mr_mip->w6->w[0]; } else { m=mr_mip->w5->w[mr_mip->ndig-1]+1; if (mr_mip->base==0) { #ifndef MR_NOFULLWIDTH if (m==0) { mr_mip->u=mr_mip->w5->w[mr_mip->ndig-1]; mr_mip->v=mr_mip->w6->w[mr_mip->ndig-1]; } else { mr_mip->u=muldvm(mr_mip->w5->w[mr_mip->ndig-1],mr_mip->w5->w[mr_mip->ndig-2],m,&sr); mr_mip->v=muldvm(mr_mip->w6->w[mr_mip->ndig-1],mr_mip->w6->w[mr_mip->ndig-2],m,&sr); } #endif } else { mr_mip->u=muldiv(mr_mip->w5->w[mr_mip->ndig-1],mr_mip->base,mr_mip->w5->w[mr_mip->ndig-2],m,&sr); mr_mip->v=muldiv(mr_mip->w6->w[mr_mip->ndig-1],mr_mip->base,mr_mip->w6->w[mr_mip->ndig-2],m,&sr); } } mr_mip->ku=mr_mip->u; mr_mip->kv=mr_mip->v; middle: forever { /* work only with most significant piece */ if (mr_mip->last) { if (mr_mip->v==0) return (mr_mip->q=(-1)); lq=MR_DIV(mr_mip->u,mr_mip->v); } else { if (((mr_mip->v+mr_mip->c)==0) || ((mr_mip->v+mr_mip->d)==0)) break; lq=MR_DIV((mr_mip->u+mr_mip->a),(mr_mip->v+mr_mip->c)); if (lq!=MR_DIV((mr_mip->u+mr_mip->b),(mr_mip->v+mr_mip->d))) break; } if (lq>=(mr_small)(MR_TOOBIG/mr_abs(mr_mip->d))) break; mr_mip->q=(int)lq; mr_mip->r=mr_mip->a-mr_mip->q*mr_mip->c; mr_mip->a=mr_mip->c; mr_mip->c=mr_mip->r; mr_mip->r=mr_mip->b-mr_mip->q*mr_mip->d; mr_mip->b=mr_mip->d; mr_mip->d=mr_mip->r; lr=mr_mip->u-lq*mr_mip->v; mr_mip->u=mr_mip->v; mr_mip->v=lr; return mr_mip->q; } mr_mip->carryon=FALSE; if (mr_mip->b==0) { /* update w5 and w6 */ mr_mip->check=OFF; divide(_MIPP_ mr_mip->w5,mr_mip->w6,mr_mip->w7); mr_mip->check=ON; if (mr_lent(mr_mip->w7)>mr_mip->nib) return (mr_mip->q=(-2)); t=mr_mip->w5,mr_mip->w5=mr_mip->w6,mr_mip->w6=t; /* swap(w5,w6) */ copy(mr_mip->w7,x); return (mr_mip->q=size(x)); } else { mr_mip->check=OFF; premult(_MIPP_ mr_mip->w5,mr_mip->c,mr_mip->w7); premult(_MIPP_ mr_mip->w5,mr_mip->a,mr_mip->w5); premult(_MIPP_ mr_mip->w6,mr_mip->b,mr_mip->w0); premult(_MIPP_ mr_mip->w6,mr_mip->d,mr_mip->w6); add(_MIPP_ mr_mip->w5,mr_mip->w0,mr_mip->w5); add(_MIPP_ mr_mip->w6,mr_mip->w7,mr_mip->w6); mr_mip->check=ON; } goto start; }
int xgcd(_MIPD_ big x,big y,big xd,big yd,big z) { /* greatest common divisor by Euclids method * * extended to also calculate xd and yd where * * z = x.xd + y.yd = gcd(x,y) * * if xd, yd not distinct, only xd calculated * * z only returned if distinct from xd and yd * * xd will always be positive, yd negative */ int s,n,iter; mr_small r,a,b,c,d; mr_small q,m,sr; #ifdef MR_FP mr_small dres; #endif #ifdef mr_dltype mr_large u,v,lr; #else mr_small u,v,lr; #endif BOOL last,dplus=TRUE; big t; #ifndef MR_GENERIC_MT miracl *mr_mip=get_mip(); #endif if (mr_mip->ERNUM) return 0; MR_IN(30) copy(x,mr_mip->w1); copy(y,mr_mip->w2); s=exsign(mr_mip->w1); insign(PLUS,mr_mip->w1); insign(PLUS,mr_mip->w2); convert(_MIPP_ 1,mr_mip->w3); zero(mr_mip->w4); last=FALSE; a=b=c=d=0; iter=0; while (size(mr_mip->w2)!=0) { if (b==0) { /* update mr_mip->w1 and mr_mip->w2 */ divide(_MIPP_ mr_mip->w1,mr_mip->w2,mr_mip->w5); t=mr_mip->w1,mr_mip->w1=mr_mip->w2,mr_mip->w2=t; /* swap(mr_mip->w1,mr_mip->w2) */ multiply(_MIPP_ mr_mip->w4,mr_mip->w5,mr_mip->w0); add(_MIPP_ mr_mip->w3,mr_mip->w0,mr_mip->w3); t=mr_mip->w3,mr_mip->w3=mr_mip->w4,mr_mip->w4=t; /* swap(xd,yd) */ iter++; } else { /* printf("a= %d b= %d c= %d d= %d \n",a,b,c,d); */ mr_pmul(_MIPP_ mr_mip->w1,c,mr_mip->w5); /* c*w1 */ mr_pmul(_MIPP_ mr_mip->w1,a,mr_mip->w1); /* a*w1 */ mr_pmul(_MIPP_ mr_mip->w2,b,mr_mip->w0); /* b*w2 */ mr_pmul(_MIPP_ mr_mip->w2,d,mr_mip->w2); /* d*w2 */ if (!dplus) { mr_psub(_MIPP_ mr_mip->w0,mr_mip->w1,mr_mip->w1); /* b*w2-a*w1 */ mr_psub(_MIPP_ mr_mip->w5,mr_mip->w2,mr_mip->w2); /* c*w1-d*w2 */ } else { mr_psub(_MIPP_ mr_mip->w1,mr_mip->w0,mr_mip->w1); /* a*w1-b*w2 */ mr_psub(_MIPP_ mr_mip->w2,mr_mip->w5,mr_mip->w2); /* d*w2-c*w1 */ } mr_pmul(_MIPP_ mr_mip->w3,c,mr_mip->w5); mr_pmul(_MIPP_ mr_mip->w3,a,mr_mip->w3); mr_pmul(_MIPP_ mr_mip->w4,b,mr_mip->w0); mr_pmul(_MIPP_ mr_mip->w4,d,mr_mip->w4); if (a==0) copy(mr_mip->w0,mr_mip->w3); else mr_padd(_MIPP_ mr_mip->w3,mr_mip->w0,mr_mip->w3); mr_padd(_MIPP_ mr_mip->w4,mr_mip->w5,mr_mip->w4); } if (mr_mip->ERNUM || size(mr_mip->w2)==0) break; n=(int)mr_mip->w1->len; if (n==1) { last=TRUE; u=mr_mip->w1->w[0]; v=mr_mip->w2->w[0]; } else { m=mr_mip->w1->w[n-1]+1; if (mr_mip->base==0) { #ifndef MR_NOFULLWIDTH #ifdef mr_dltype /* use double length type if available */ if (n>2 && m!=0) { /* squeeze out as much significance as possible */ MR_TOP(u)=muldvm(mr_mip->w1->w[n-1],mr_mip->w1->w[n-2],m,&sr); MR_BOT(u)=muldvm(sr,mr_mip->w1->w[n-3],m,&sr); MR_TOP(v)=muldvm(mr_mip->w2->w[n-1],mr_mip->w2->w[n-2],m,&sr); MR_BOT(v)=muldvm(sr,mr_mip->w2->w[n-3],m,&sr); } else { MR_TOP(u)=mr_mip->w1->w[n-1]; MR_BOT(u)=mr_mip->w1->w[n-2]; MR_TOP(v)=mr_mip->w2->w[n-1]; MR_BOT(v)=mr_mip->w2->w[n-2]; if (n==2) last=TRUE; } #else if (m==0) { u=mr_mip->w1->w[n-1]; v=mr_mip->w2->w[n-1]; } else { u=muldvm(mr_mip->w1->w[n-1],mr_mip->w1->w[n-2],m,&sr); v=muldvm(mr_mip->w2->w[n-1],mr_mip->w2->w[n-2],m,&sr); } #endif #endif } else { #ifdef mr_dltype if (n>2) { /* squeeze out as much significance as possible */ u=muldiv(mr_mip->w1->w[n-1],mr_mip->base,mr_mip->w1->w[n-2],m,&sr); u=u*mr_mip->base+muldiv(sr,mr_mip->base,mr_mip->w1->w[n-3],m,&sr); v=muldiv(mr_mip->w2->w[n-1],mr_mip->base,mr_mip->w2->w[n-2],m,&sr); v=v*mr_mip->base+muldiv(sr,mr_mip->base,mr_mip->w2->w[n-3],m,&sr); } else { u=(mr_large)mr_mip->base*mr_mip->w1->w[n-1]+mr_mip->w1->w[n-2]; v=(mr_large)mr_mip->base*mr_mip->w2->w[n-1]+mr_mip->w2->w[n-2]; last=TRUE; } #else u=muldiv(mr_mip->w1->w[n-1],mr_mip->base,mr_mip->w1->w[n-2],m,&sr); v=muldiv(mr_mip->w2->w[n-1],mr_mip->base,mr_mip->w2->w[n-2],m,&sr); #endif } } dplus=TRUE; a=1; b=0; c=0; d=1; forever { /* work only with most significant piece */ if (last) { if (v==0) break; q=qdiv(u,v); if (q==0) break; } else { if (dplus) { if (v-c==0 || v+d==0) break; q=qdiv(u+a,v-c); if (q==0) break; if (q!=qdiv(u-b,v+d)) break; } else { if (v+c==0 || v-d==0) break; q=qdiv(u-a,v+c); if (q==0) break; if (q!=qdiv(u+b,v-d)) break; } } if (q==1) { if (b+d >= MAXBASE) break; r=a+c; a=c; c=r; r=b+d; b=d; d=r; lr=u-v; u=v; v=lr; } else { if (q>=MR_DIV(MAXBASE-b,d)) break; r=a+q*c; a=c; c=r; r=b+q*d; b=d; d=r; lr=u-q*v; u=v; v=lr; } iter++; dplus=!dplus; } iter%=2; } if (s==MINUS) iter++; if (iter%2==1) subtract(_MIPP_ y,mr_mip->w3,mr_mip->w3); if (xd!=yd) { negify(x,mr_mip->w2); mad(_MIPP_ mr_mip->w2,mr_mip->w3,mr_mip->w1,y,mr_mip->w4,mr_mip->w4); copy(mr_mip->w4,yd); } copy(mr_mip->w3,xd); if (z!=xd && z!=yd) copy(mr_mip->w1,z); MR_OUT return (size(mr_mip->w1)); }
int egcd(_MIPD_ big x,big y,big z) { /* greatest common divisor z=gcd(x,y) by Euclids * * method using Lehmers algorithm for big numbers */ int q,r,a,b,c,d,n; mr_small sr,m,sm; mr_small u,v,lq,lr; #ifdef MR_FP mr_small dres; #endif big t; #ifdef MR_OS_THREADS miracl *mr_mip=get_mip(); #endif if (mr_mip->ERNUM) return 0; MR_IN(12) copy(x,mr_mip->w1); copy(y,mr_mip->w2); insign(PLUS,mr_mip->w1); insign(PLUS,mr_mip->w2); a=b=c=d=0; while (size(mr_mip->w2)!=0) { /* printf("a= %d b= %d c= %d d=%d\n",a,b,c,d); */ if (b==0) { /* update w1 and w2 */ divide(_MIPP_ mr_mip->w1,mr_mip->w2,mr_mip->w2); t=mr_mip->w1,mr_mip->w1=mr_mip->w2,mr_mip->w2=t; /* swap(w1,w2) */ } else { premult(_MIPP_ mr_mip->w1,c,z); premult(_MIPP_ mr_mip->w1,a,mr_mip->w1); premult(_MIPP_ mr_mip->w2,b,mr_mip->w0); premult(_MIPP_ mr_mip->w2,d,mr_mip->w2); add(_MIPP_ mr_mip->w1,mr_mip->w0,mr_mip->w1); add(_MIPP_ mr_mip->w2,z,mr_mip->w2); } if (mr_mip->ERNUM || size(mr_mip->w2)==0) break; n=(int)mr_mip->w1->len; if (mr_mip->w2->len==1) { /* special case if mr_mip->w2 is now small */ sm=mr_mip->w2->w[0]; #ifdef MR_FP_ROUNDING sr=mr_sdiv(_MIPP_ mr_mip->w1,sm,mr_invert(sm),mr_mip->w1); #else sr=mr_sdiv(_MIPP_ mr_mip->w1,sm,mr_mip->w1); #endif if (sr==0) { copy(mr_mip->w2,mr_mip->w1); break; } zero(mr_mip->w1); mr_mip->w1->len=1; mr_mip->w1->w[0]=sr; while ((sr=MR_REMAIN(mr_mip->w2->w[0],mr_mip->w1->w[0]))!=0) mr_mip->w2->w[0]=mr_mip->w1->w[0],mr_mip->w1->w[0]=sr; break; } a=1; b=0; c=0; d=1; m=mr_mip->w1->w[n-1]+1; /* printf("m= %d\n",m); */ #ifndef MR_SIMPLE_BASE if (mr_mip->base==0) { #endif #ifndef MR_NOFULLWIDTH if (m==0) { u=mr_mip->w1->w[n-1]; v=mr_mip->w2->w[n-1]; } else { /* printf("w1[n-1]= %d w1[n-2]= %d\n", mr_mip->w1->w[n-1],mr_mip->w1->w[n-2]); printf("w2[n-1]= %d w2[n-2]= %d\n", mr_mip->w2->w[n-1],mr_mip->w2->w[n-2]);*/ u=muldvm(mr_mip->w1->w[n-1],mr_mip->w1->w[n-2],m,&sr); v=muldvm(mr_mip->w2->w[n-1],mr_mip->w2->w[n-2],m,&sr); } #endif #ifndef MR_SIMPLE_BASE } else { u=muldiv(mr_mip->w1->w[n-1],mr_mip->base,mr_mip->w1->w[n-2],m,&sr); v=muldiv(mr_mip->w2->w[n-1],mr_mip->base,mr_mip->w2->w[n-2],m,&sr); } #endif /* printf("u= %d v= %d\n",u,v);*/ forever { /* work only with most significant piece */ if (((v+c)==0) || ((v+d)==0)) break; lq=MR_DIV((u+a),(v+c)); if (lq!=MR_DIV((u+b),(v+d))) break; if (lq>=(mr_small)(MR_TOOBIG/mr_abs(d))) break; q=(int)lq; r=a-q*c; a=c; c=r; r=b-q*d; b=d; d=r; lr=u-lq*v; u=v; v=lr; } } copy(mr_mip->w1,z); MR_OUT return (size(mr_mip->w1)); }
void build(_MIPD_ flash x,int (*gen)(_MIPT_ big,int)) { /* Build x from its regular c.f. * * generated by gen() */ mr_small ex1,ex2,ex,st,sr; int a,b,c,d,rm,q,n,prc,lw2,lw4,lz; BOOL finoff,last; big t; #ifdef MR_OS_THREADS miracl *mr_mip=get_mip(); #endif if (mr_mip->ERNUM) return; MR_IN(48) zero(mr_mip->w1); convert(_MIPP_ 1,mr_mip->w2); convert(_MIPP_ 1,mr_mip->w3); zero(mr_mip->w4); finoff=FALSE; last=FALSE; n=0; q=(*gen)(_MIPP_ x,n); /* Note - first quotient may be zero */ ex=mr_mip->base-1; if (mr_mip->nib==mr_mip->workprec) prc=mr_mip->nib; else prc=mr_mip->workprec+1; while (!mr_mip->ERNUM && q>=0) { if (q==MR_TOOBIG || n==0 || finoff) { if (q!=MR_TOOBIG) convert(_MIPP_ q,x); else last=FALSE; mr_mip->check=OFF; multiply(_MIPP_ mr_mip->w2,x,mr_mip->w0); subtract(_MIPP_ mr_mip->w1,mr_mip->w0,mr_mip->w7); mr_mip->check=ON; if ((int)(mr_mip->w7->len&MR_OBITS)>mr_mip->nib) break; copy(mr_mip->w7,mr_mip->w1); t=mr_mip->w1,mr_mip->w1=mr_mip->w2,mr_mip->w2=t; /* swap(w1,w2) */ mr_mip->check=OFF; multiply(_MIPP_ mr_mip->w4,x,mr_mip->w0); subtract(_MIPP_ mr_mip->w3,mr_mip->w0,mr_mip->w7); mr_mip->check=ON; if ((int)(mr_mip->w7->len&MR_OBITS)>mr_mip->nib) { /* oops! */ fpack(_MIPP_ mr_mip->w1,mr_mip->w4,x); negify(x,x); mr_mip->EXACT=FALSE; MR_OUT return; } copy(mr_mip->w7,mr_mip->w3); t=mr_mip->w3,mr_mip->w3=mr_mip->w4,mr_mip->w4=t; /* swap(w3,w4) */ n++; } lw2=(int)(mr_mip->w2->len&MR_OBITS); lw4=(int)(mr_mip->w4->len&MR_OBITS); lz=lw2+lw4; if (lz > prc) break; /* too big - exit */ if (last) { if (finoff) break; finoff=TRUE; q=(*gen)(_MIPP_ x,n); continue; } if (lz>=prc-1) { /* nearly finished - so be careful not to overshoot */ if (mr_mip->base==0) { #ifndef MR_NOFULLWIDTH st=mr_mip->w2->w[lw2-1]+1; if (st==0) ex1=1; else ex1=muldvm((mr_small)1,(mr_small)0,st,&sr); st=mr_mip->w4->w[lw4-1]+1; if (st==0) ex2=1; else ex2=muldvm((mr_small)1,(mr_small)0,st,&sr); #endif } else { ex1=mr_mip->base/(mr_mip->w2->w[lw2-1]+1); ex2=mr_mip->base/(mr_mip->w4->w[lw4-1]+1); } if (ex2>ex1) ex=ex1,ex1=ex2,ex2=ex; if (lz==prc) ex=ex2; else ex=ex1; last=TRUE; } a=1; b=0; c=0; d=1; forever { q=(*gen)(_MIPP_ x,n); if (q<0 || q>=MR_TOOBIG/mr_abs(d)) { /* there could be more.... *** V3.21 mod *** */ last=FALSE; break; } rm=b-q*d; b=d; d=rm; rm=a-q*c; a=c; c=rm; n++; if ((mr_small)(mr_abs(c-d))>ex) break; } premult(_MIPP_ mr_mip->w1,c,mr_mip->w7); premult(_MIPP_ mr_mip->w1,a,mr_mip->w1); premult(_MIPP_ mr_mip->w2,b,mr_mip->w0); premult(_MIPP_ mr_mip->w2,d,mr_mip->w2); add(_MIPP_ mr_mip->w1,mr_mip->w0,mr_mip->w1); add(_MIPP_ mr_mip->w2,mr_mip->w7,mr_mip->w2); premult(_MIPP_ mr_mip->w3,c,mr_mip->w7); premult(_MIPP_ mr_mip->w3,a,mr_mip->w3); premult(_MIPP_ mr_mip->w4,b,mr_mip->w0); premult(_MIPP_ mr_mip->w4,d,mr_mip->w4); add(_MIPP_ mr_mip->w3,mr_mip->w0,mr_mip->w3); add(_MIPP_ mr_mip->w4,mr_mip->w7,mr_mip->w4); }
int xgcd(_MIPD_ big x,big y,big xd,big yd,big z) { /* greatest common divisor by Euclids method * * extended to also calculate xd and yd where * * z = x.xd + y.yd = gcd(x,y) * * if xd, yd not distinct, only xd calculated * * z only returned if distinct from xd and yd * * xd will always be positive, yd negative */ int q,r,a,b,c,d,s,n; mr_small m,sr; #ifdef mr_dltype mr_large u,v,lq,lr; #else mr_small u,v,lq,lr; #endif BOOL last; big t; #ifndef MR_GENERIC_MT miracl *mr_mip=get_mip(); #endif if (mr_mip->ERNUM) return 0; MR_IN(30) copy(x,mr_mip->w1); copy(y,mr_mip->w2); s=exsign(mr_mip->w1); insign(PLUS,mr_mip->w1); insign(PLUS,mr_mip->w2); /* copy(mr_mip->w1,mr_mip->w3); copy(mr_mip->w2,mr_mip->w4); */ convert(_MIPP_ 1,mr_mip->w3); zero(mr_mip->w4); last=FALSE; a=b=c=d=0; while (size(mr_mip->w2)!=0) { if (b==0) { /* update mr_mip->w1 and mr_mip->w2 */ divide(_MIPP_ mr_mip->w1,mr_mip->w2,mr_mip->w5); t=mr_mip->w1,mr_mip->w1=mr_mip->w2,mr_mip->w2=t; /* swap(mr_mip->w1,mr_mip->w2) */ multiply(_MIPP_ mr_mip->w4,mr_mip->w5,mr_mip->w0); subtract(_MIPP_ mr_mip->w3,mr_mip->w0,mr_mip->w3); t=mr_mip->w3,mr_mip->w3=mr_mip->w4,mr_mip->w4=t; /* swap(xd,yd) */ } else { premult(_MIPP_ mr_mip->w1,c,mr_mip->w5); premult(_MIPP_ mr_mip->w1,a,mr_mip->w1); premult(_MIPP_ mr_mip->w2,b,mr_mip->w0); premult(_MIPP_ mr_mip->w2,d,mr_mip->w2); add_r(_MIPP_ mr_mip->w1,mr_mip->w0,mr_mip->w1); add_r(_MIPP_ mr_mip->w2,mr_mip->w5,mr_mip->w2); premult(_MIPP_ mr_mip->w3,c,mr_mip->w5); premult(_MIPP_ mr_mip->w3,a,mr_mip->w3); premult(_MIPP_ mr_mip->w4,b,mr_mip->w0); premult(_MIPP_ mr_mip->w4,d,mr_mip->w4); add_r(_MIPP_ mr_mip->w3,mr_mip->w0,mr_mip->w3); add_r(_MIPP_ mr_mip->w4,mr_mip->w5,mr_mip->w4); } if (mr_mip->ERNUM || size(mr_mip->w2)==0) break; n=(int)mr_mip->w1[0]; a=1; b=0; c=0; d=1; if (n==1) { last=TRUE; u=mr_mip->w1[1]; v=mr_mip->w2[1]; } else { m=mr_mip->w1[n]+1; if (mr_mip->base==0) { #ifdef mr_dltype /* use double length type if available */ if (n>2 && m!=0) { /* squeeze out as much significance as possible */ MR_TOP(u)=muldvm(mr_mip->w1[n],mr_mip->w1[n-1],m,&sr); MR_BOT(u)=muldvm(sr,mr_mip->w1[n-2],m,&sr); MR_TOP(v)=muldvm(mr_mip->w2[n],mr_mip->w2[n-1],m,&sr); MR_BOT(v)=muldvm(sr,mr_mip->w2[n-2],m,&sr); } else { MR_TOP(u)=mr_mip->w1[n]; MR_BOT(u)=mr_mip->w1[n-1]; MR_TOP(v)=mr_mip->w2[n]; MR_BOT(v)=mr_mip->w2[n-1]; if (n==2) last=TRUE; } #else if (m==0) { u=mr_mip->w1[n]; v=mr_mip->w2[n]; } else { u=muldvm(mr_mip->w1[n],mr_mip->w1[n-1],m,&sr); v=muldvm(mr_mip->w2[n],mr_mip->w2[n-1],m,&sr); } #endif } else { #ifdef mr_dltype /* use double length type if available */ if (n>2) { /* squeeze out as much significance as possible */ u=muldiv(mr_mip->w1[n],mr_mip->base,mr_mip->w1[n-1],m,&sr); u=u*mr_mip->base+muldiv(sr,mr_mip->base,mr_mip->w1[n-2],m,&sr); v=muldiv(mr_mip->w2[n],mr_mip->base,mr_mip->w2[n-1],m,&sr); v=v*mr_mip->base+muldiv(sr,mr_mip->base,mr_mip->w2[n-2],m,&sr); } else { u=(mr_large)mr_mip->base*mr_mip->w1[n]+mr_mip->w1[n-1]; v=(mr_large)mr_mip->base*mr_mip->w2[n]+mr_mip->w2[n-1]; last=TRUE; } #else u=muldiv(mr_mip->w1[n],mr_mip->base,mr_mip->w1[n-1],m,&sr); v=muldiv(mr_mip->w2[n],mr_mip->base,mr_mip->w2[n-1],m,&sr); #endif } } forever { /* work only with most significant piece */ if (last) { if (v==0) break; lq=u/v; } else { if (((v+c)==0) || ((v+d)==0)) break; lq=(u+a)/(v+c); if (lq!=(u+b)/(v+d)) break; } #ifdef mr_dltype if (lq>=(mr_large)(MR_TOOBIG/abs(d))) break; #else if (lq>=(mr_small)(MR_TOOBIG/abs(d))) break; #endif q=(int)lq; r=a-q*c; a=c; c=r; r=b-q*d; b=d; d=r; lr=u-lq*v; u=v; v=lr; } } if (s==MINUS) negate(mr_mip->w3,mr_mip->w3); if (size(mr_mip->w3)<=0) add_r(_MIPP_ mr_mip->w3,y,mr_mip->w3); if (xd!=yd) { negate(x,mr_mip->w2); mad(_MIPP_ mr_mip->w2,mr_mip->w3,mr_mip->w1,y,mr_mip->w4,mr_mip->w4); copy(mr_mip->w4,yd); } copy(mr_mip->w3,xd); if (z!=xd && z!=yd) copy(mr_mip->w1,z); MR_OUT return (size(mr_mip->w1)); }