Maciej W. Rozycki wrote: > On Sat, 20 Sep 2008, Atsushi Nemoto wrote: > > > @@ -229,6 +239,9 @@ LEAF(csum_partial) > > > > /* Still a full word to go */ > > ulw t1, (src) > > +#ifdef USE_DOUBLE > > + add t1, zero /* clear upper 32bit */ > > +#endif > > PTR_ADDIU src, 4 > > ADDC(sum, t1) > > > > Unfortunately you can't zero-extend with a single instruction (you can > use a single sll(v) to sign-extend), unless the R2 ISA provides some > suitable oddity (which I haven't checked). AFAIR dext can do this for MIPS64 R2. Thiemo
