Changeset 73a9ffb in git for libpolys/coeffs/rmodulo2m.cc

Timestamp:

May 26, 2011, 10:29:03 AM (12 years ago)

Author:

Frank Seelisch <seelisch@…>

Branches:

(u'spielwiese', '8e0ad00ce244dfd0756200662572aef8402f13d5')

Children:

488808e90a9444d2ce5d16be059643fdd2e8629e

Parents:

e676cdf123bc41ae953d7fd58106263f5fd02d0c

git-author:

Frank Seelisch <seelisch@mathematik.uni-kl.de>2011-05-26 10:29:03+02:00

git-committer:

Mohamed Barakat <mohamed.barakat@rwth-aachen.de>2011-11-09 12:36:53+01:00

Message:

made sure that ch is properly set everywhere, and ch >= 0; more ASSUMEs

File:

• libpolys/coeffs/rmodulo2m.cc (modified) (5 diffs)

libpolys/coeffs/rmodulo2m.cc

@@ -24 +24 @@
 #include <string.h>
 
+/// Our Type!
+static const n_coeffType ID = n_Z2m;
+
 extern omBin gmp_nrz_bin; /* init in rintegers*/
 
@@ -44 +47 @@
 BOOLEAN nr2mInitChar (coeffs r, void* p)
 {
+  assume( getCoeffType(r) == ID );
   nr2mInitExp((int)(long)(p), r);
   r->cfKillChar    = ndKillChar; /* dummy*/
@@ -49 +53 @@
 
   r->ringtype = 1;
-  r->type = n_Z2m;
+  
+  /* next cast may yield an overflow as mod2mMask is an unsigned long */
+  r->ch = (int)r->mod2mMask + 1;
 
   r->cfInit        = nr2mInit;
@@ -640 +646 @@
   else
   {
-    /* code unexpectedly called with m = 1; we go on with m = 2: */
+    /* code unexpectedly called with m = 1; we continue with m = 2: */
     r->mod2mMask = 3; /* i.e., '11' in binary representation */
   }
-  r->ch = r->mod2mMask + 1;
 }
 
@@ -650 +655 @@
   nr2mSetExp(m, r);
   if (m < 2)
-    WarnS("nr2mInitExp unexpectedly called with m = 1 (we go on with Z/2^2");
+    WarnS("nr2mInitExp unexpectedly called with m = 1 (we continue with Z/2^2");
 }