gcc/testsuite/gcc.c-torture/execute/20020406-1.c

   1 // Origin: abbott@dima.unige.it
   2 // PR c/5120
   3
   4 extern void * malloc (__SIZE_TYPE__);
   5 extern void * calloc (__SIZE_TYPE__, __SIZE_TYPE__);
   6
   7 typedef unsigned int FFelem;
   8
   9 FFelem FFmul(const FFelem x, const FFelem y)
  10 {
  11   return x;
  12 }
  13
  14
  15 struct DUPFFstruct
  16 {
  17   int maxdeg;
  18   int deg;
  19   FFelem *coeffs;
  20 };
  21
  22 typedef struct DUPFFstruct *DUPFF;
  23
  24
  25 int DUPFFdeg(const DUPFF f)
  26 {
  27   return f->deg;
  28 }
  29
  30
  31 DUPFF DUPFFnew(const int maxdeg)
  32 {
  33   DUPFF ans = (DUPFF)malloc(sizeof(struct DUPFFstruct));
  34   ans->coeffs = 0;
  35   if (maxdeg >= 0) ans->coeffs = (FFelem*)calloc(maxdeg+1,sizeof(FFelem));
  36   ans->maxdeg = maxdeg;
  37   ans->deg = -1;
  38   return ans;
  39 }
  40
  41 void DUPFFfree(DUPFF x)
  42 {
  43 }
  44
  45 void DUPFFswap(DUPFF x, DUPFF y)
  46 {
  47 }
  48
  49
  50 DUPFF DUPFFcopy(const DUPFF x)
  51 {
  52   return x;
  53 }
  54
  55
  56 void DUPFFshift_add(DUPFF f, const DUPFF g, int deg, const FFelem coeff)
  57 {
  58 }
  59
  60
  61 DUPFF DUPFFexgcd(DUPFF *fcofac, DUPFF *gcofac, const DUPFF f, const DUPFF g)
  62 {
  63   DUPFF u, v, uf, ug, vf, vg;
  64   FFelem q, lcu, lcvrecip, p;
  65   int df, dg, du, dv;
  66
  67   printf("DUPFFexgcd called on degrees %d and %d\n", DUPFFdeg(f), DUPFFdeg(g));
  68   if (DUPFFdeg(f) < DUPFFdeg(g)) return DUPFFexgcd(gcofac, fcofac, g, f);  /*** BUG IN THIS LINE ***/
  69   if (DUPFFdeg(f) != 2 || DUPFFdeg(g) != 1) abort();
  70   if (f->coeffs[0] == 0) return f;
  71   /****** NEVER REACH HERE IN THE EXAMPLE ******/
  72   p = 2;
  73
  74   df = DUPFFdeg(f);  if (df < 0) df = 0; /* both inputs are zero */
  75   dg = DUPFFdeg(g);  if (dg < 0) dg = 0; /* one input is zero */
  76   u = DUPFFcopy(f);
  77   v = DUPFFcopy(g);
  78
  79   uf = DUPFFnew(dg); uf->coeffs[0] = 1; uf->deg = 0;
  80   ug = DUPFFnew(df);
  81   vf = DUPFFnew(dg);
  82   vg = DUPFFnew(df); vg->coeffs[0] = 1; vg->deg = 0;
  83
  84   while (DUPFFdeg(v) > 0)
  85   {
  86     dv = DUPFFdeg(v);
  87     lcvrecip = FFmul(1, v->coeffs[dv]);
  88     while (DUPFFdeg(u) >= dv)
  89     {
  90       du = DUPFFdeg(u);
  91       lcu = u->coeffs[du];
  92       q = FFmul(lcu, lcvrecip);
  93       DUPFFshift_add(u, v, du-dv, p-q);
  94       DUPFFshift_add(uf, vf, du-dv, p-q);
  95       DUPFFshift_add(ug, vg, du-dv, p-q);
  96     }
  97     DUPFFswap(u, v);
  98     DUPFFswap(uf, vf);
  99     DUPFFswap(ug, vg);
 100   }
 101   if (DUPFFdeg(v) == 0)
 102   {
 103     DUPFFswap(u, v);
 104     DUPFFswap(uf, vf);
 105     DUPFFswap(ug, vg);
 106   }
 107   DUPFFfree(vf);
 108   DUPFFfree(vg);
 109   DUPFFfree(v);
 110   *fcofac = uf;
 111   *gcofac = ug;
 112   return u;
 113 }
 114
 115
 116
 117 int main()
 118 {
 119   DUPFF f, g, cf, cg, h;
 120   f = DUPFFnew(1); f->coeffs[1] = 1; f->deg = 1;
 121   g = DUPFFnew(2); g->coeffs[2] = 1; g->deg = 2;
 122
 123   printf("calling DUPFFexgcd on degrees %d and %d\n", DUPFFdeg(f), DUPFFdeg(g)) ;
 124   h = DUPFFexgcd(&cf, &cg, f, g);
 125   return 0;
 126 }