3 # ====================================================================
4 # Written by Andy Polyakov <appro@fy.chalmers.se> for the OpenSSL
5 # project. The module is, however, dual licensed under OpenSSL and
6 # CRYPTOGAMS licenses depending on where you obtain it. For further
7 # details see http://www.openssl.org/~appro/cryptogams/.
8 # ====================================================================
10 # On 21264 RSA sign performance improves by 70/35/20/15 percent for
11 # 512/1024/2048/4096 bit key lengths. This is against vendor compiler
12 # instructed to '-tune host' code with in-line assembler. Other
13 # benchmarks improve by 15-20%. To anchor it to something else, the
14 # code provides approximately the same performance per GHz as AMD64.
15 # I.e. if you compare 1GHz 21264 and 2GHz Opteron, you'll observe ~2x
19 $rp="a0"; # BN_ULONG *rp,
20 $ap="a1"; # const BN_ULONG *ap,
21 $bp="a2"; # const BN_ULONG *bp,
22 $np="a3"; # const BN_ULONG *np,
23 $n0="a4"; # const BN_ULONG *n0,
24 $num="a5"; # int num);
45 #include <asm/regdef.h>
78 ldq $hi0,0($ap) # ap[0]
82 ldq $bi,0($bp) # bp[0]
83 lda AT,-4096(zero) # mov -4096,AT
88 ldq $hi1,0($np) # np[0]
203 s8addq $j,$np,$nj #U0
207 addq $alo,$hi0,$lo0 #L1
210 mulq $aj,$bi,$alo #U1
211 cmpult $lo0,$hi0,AT #L0
212 addq $nlo,$hi1,$lo1 #L1
215 mulq $nj,$m1,$nlo #U1
216 addq $ahi,AT,$hi0 #L0
217 addq $lo0,$tj,$lo0 #L1
218 cmpult $lo1,$hi1,v0 #U0
220 umulh $aj,$bi,$ahi #U1
221 cmpult $lo0,$tj,AT #L0
222 addq $lo1,$lo0,$lo1 #L1
223 addq $nhi,v0,$hi1 #U0
225 umulh $nj,$m1,$nhi #U1
226 s8addq $j,$ap,$aj #L0
227 cmpult $lo1,$lo0,v0 #L1
228 cmplt $j,$num,$tj #U0 # borrow $tj
230 addq $hi0,AT,$hi0 #L0
231 addq $hi1,v0,$hi1 #U1
255 cmpult $lo1,$hi0,$hi1
261 cmplt $i,$num,$tj # borrow $tj
265 s8addq $num,sp,$tj # &tp[num]
266 mov $rp,$bp # put rp aside
269 mov 0,$hi0 # clear borrow bit
272 .Lsub: ldq $lo0,0($tp)
276 subq $lo0,$lo1,$lo1 # tp[i]-np[i]
279 cmpult $lo1,$lo0,$hi0
286 subq $hi1,$hi0,$hi0 # handle upmost overflow bit
288 mov $bp,$rp # restore rp
292 bis $bp,$ap,$ap # ap=borrow?tp:rp
295 .Lcopy: ldq $aj,0($ap) # copy or in-place refresh
299 stq zero,-8($tp) # zap tp
316 .ascii "Montgomery Multiplication for Alpha, CRYPTOGAMS by <appro\@openssl.org>"