X-Git-Url: https://git.distorted.org.uk/u/mdw/catacomb/blobdiff_plain/ce541a0ec0b78847792b0a81b829bc76f9c5efcb..c29970a7717261e63ffaabb3c67381f13c5dbca5:/gfreduce.c

diff --git a/gfreduce.c b/gfreduce.c
index bdf3579..01ca678 100644
--- a/gfreduce.c
+++ b/gfreduce.c
@@ -90,7 +90,7 @@ void gfreduce_create(gfreduce *r, mp *p)
   unsigned long i;
   gfreduce_instr *ip;
   unsigned f = 0;
-  size_t w, ww, wi, wl, ll;
+  size_t w, ww, wi, wl, ll, bb;
 
   /* --- Sort out the easy stuff --- */
 
@@ -121,6 +121,7 @@ void gfreduce_create(gfreduce *r, mp *p)
   wi = DA_LEN(&iv);
   f = 0;
   ll = 0;
+  bb = MPW_BITS - dw;
   for (i = 0, mp_scan(&sc, p); mp_step(&sc) && i < d; i++) {
     if (!mp_bit(&sc))
       continue;
@@ -149,8 +150,8 @@ void gfreduce_create(gfreduce *r, mp *p)
       w = ww;
       wi = DA_LEN(&iv);
     }
-    INSTR(GFRI_LSL, (MPW_BITS + i - d)%MPW_BITS);
-    if ((MPW_BITS + i - d)%MPW_BITS)
+    INSTR(GFRI_LSL, (bb + i)%MPW_BITS);
+    if ((bb + i)%MPW_BITS)
       f |= f_lsr;
   }
   wl = DA_LEN(&iv);