ec-bin (ec_binproj): Make curve setup faster.

[u/mdw/catacomb] / mpreduce.c

diff --git a/mpreduce.c b/mpreduce.c
index d99ff16..bc41f60 100644 (file)
--- a/mpreduce.c
+++ b/mpreduce.c
@@ -60,7 +60,7 @@ int mpreduce_create(mpreduce *r, mp *p)
   instr_v iv = DA_INIT;
   unsigned long d, i;
   unsigned op;
-  size_t w, b;
+  size_t w, b, bb;
 
   /* --- Fill in the easy stuff --- */
 
@@ -101,10 +101,12 @@ int mpreduce_create(mpreduce *r, mp *p)
       case X0 | 0: st =  Z; printf("+ %lu\n", i - 1); break;
     }
   }
-  if (st >= X) printf("+ %lu\n", i);
+  if (st >= X) printf("+ %lu\n", i - 1);
+  st = Z;
 #endif
 
-  for (i = 0, mp_scan(&sc, p); i < d  - 1 && mp_step(&sc); i++) {
+  bb = MPW_BITS - (d + 1)%MPW_BITS;
+  for (i = 0, mp_scan(&sc, p); i < d && mp_step(&sc); i++) {
     switch (st | mp_bit(&sc)) {
       case  Z | 1: st = Z1; break;
       case Z1 | 0: st =  Z; op = MPRI_SUB; goto instr;
@@ -114,11 +116,11 @@ int mpreduce_create(mpreduce *r, mp *p)
       case X0 | 0: st =  Z; op = MPRI_SUB; goto instr;
       instr:
        w = (d - i)/MPW_BITS + 1;
-       b = (MPW_BITS + i - d - 1)%MPW_BITS;
+       b = (bb + i)%MPW_BITS;
        INSTR(op | !!b, w, b);
     }
   }
-  if ((DA(&iv)[DA_LEN(&iv) - 1].op & ~1u) == MPRI_SUB) {
+  if (DA_LEN(&iv) && (DA(&iv)[DA_LEN(&iv) - 1].op & ~1u) == MPRI_SUB) {
     mp_drop(r->p);
     DA_DESTROY(&iv);
     return (-1);
@@ -129,7 +131,9 @@ int mpreduce_create(mpreduce *r, mp *p)
   /* --- Wrap up --- */
 
   r->in = DA_LEN(&iv);
-  if (!r->s) {
+  if (!r->in)
+    r->iv = 0;
+  else if (!r->s) {
     r->iv = xmalloc(r->in * sizeof(mpreduce_instr));
     memcpy(r->iv, DA(&iv), r->in * sizeof(mpreduce_instr));
   } else {
@@ -151,6 +155,10 @@ int mpreduce_create(mpreduce *r, mp *p)
     }
   }
   DA_DESTROY(&iv);
+
+#ifdef DEBUG
+  mpreduce_dump(r, stdout);
+#endif
   return (0);
 }
 
@@ -166,7 +174,7 @@ int mpreduce_create(mpreduce *r, mp *p)
 void mpreduce_destroy(mpreduce *r)
 {
   mp_drop(r->p);
-  xfree(r->iv);
+  if (r->iv) xfree(r->iv);
 }
 
 /* --- @mpreduce_dump@ --- *
@@ -285,9 +293,9 @@ mp *mpreduce_do(mpreduce *r, mp *d, mp *x)
        *vl = 0;
        run(r->iv, il, vl, z);
 #ifdef DEBUG
-  MP_PRINTX("x", x);
-  mp_div(0, &_rr, x, r->p);
-  assert(MP_EQ(_r, _rr));
+       MP_PRINTX("x", x);
+       mp_div(0, &_rr, x, r->p);
+       assert(MP_EQ(_r, _rr));
 #endif
       }
     }
@@ -297,9 +305,9 @@ mp *mpreduce_do(mpreduce *r, mp *d, mp *x)
        *vl &= ((1 << r->s) - 1);
        run(r->iv + r->in, il + r->in, vl, z);
 #ifdef DEBUG
-  MP_PRINTX("x", x);
-  mp_div(0, &_rr, x, r->p);
-  assert(MP_EQ(_r, _rr));
+       MP_PRINTX("x", x);
+       mp_div(0, &_rr, x, r->p);
+       assert(MP_EQ(_r, _rr));
 #endif
       }
     }