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the divisor was a bit more complex than I first saw. The lost bit can't just be discarded, as there are cases where it is important. For example, look at dividing 320000 with 80000 vs. 80001 (all decimals), the difference is crucial. The trick here is to check if that lost bit was 1, and in that case, do the following: 1. subtract the quotient from the remainder 2. as long as the remainder is negative, add the divisor (the whole divisor, not the shofted down copy) to it, and decrease the quotient by one. There's probably a nice mathematical proof for this already, but I won't bother with that, unless someone requests it from me. |
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| .. | ||
| alpha | ||
| alpha.works | ||
| x86 | ||
| .cvsignore | ||
| alpha.s | ||
| alpha.s.works | ||
| bn-586.pl | ||
| bn-alpha.pl | ||
| ca.pl | ||
| co-586.pl | ||
| co-alpha.pl | ||
| ia64.S | ||
| mips1.s | ||
| mips3.s | ||
| pa-risc2.s | ||
| pa-risc2.s.old | ||
| pa-risc2W.s | ||
| pa-risc.s | ||
| r3000.s | ||
| README | ||
| sparcv8.S | ||
| sparcv8plus.S | ||
| vms.mar | ||
| x86.pl | ||
<OBSOLETE> All assember in this directory are just version of the file crypto/bn/bn_asm.c. Quite a few of these files are just the assember output from gcc since on quite a few machines they are 2 times faster than the system compiler. For the x86, I have hand written assember because of the bad job all compilers seem to do on it. This normally gives a 2 time speed up in the RSA routines. For the DEC alpha, I also hand wrote the assember (except the division which is just the output from the C compiler pasted on the end of the file). On the 2 alpha C compilers I had access to, it was not possible to do 64b x 64b -> 128b calculations (both long and the long long data types were 64 bits). So the hand assember gives access to the 128 bit result and a 2 times speedup :-). There are 3 versions of assember for the HP PA-RISC. pa-risc.s is the origional one which works fine and generated using gcc :-) pa-risc2W.s and pa-risc2.s are 64 and 32-bit PA-RISC 2.0 implementations by Chris Ruemmler from HP (with some help from the HP C compiler). </OBSOLETE>