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 # ====================================================================
12 # The reason for undertaken effort is basically following. Even though
13 # Power 6 CPU operates at incredible 4.7GHz clock frequency, its PKI
14 # performance was observed to be less than impressive, essentially as
15 # fast as 1.8GHz PPC970, or 2.6 times(!) slower than one would hope.
16 # Well, it's not surprising that IBM had to make some sacrifices to
17 # boost the clock frequency that much, but no overall improvement?
18 # Having observed how much difference did switching to FPU make on
19 # UltraSPARC, playing same stunt on Power 6 appeared appropriate...
20 # Unfortunately the resulting performance improvement is not as
21 # impressive, ~30%, and in absolute terms is still very far from what
22 # one would expect from 4.7GHz CPU. There is a chance that I'm doing
23 # something wrong, but in the lack of assembler level micro-profiling
24 # data or at least decent platform guide I can't tell... Or better
25 # results might be achieved with VMX... Anyway, this module provides
26 # *worse* performance on other PowerPC implementations, ~40-15% slower
27 # on PPC970 depending on key length and ~40% slower on Power 5 for all
28 # key lengths. As it's obviously inappropriate as "best all-round"
29 # alternative, it has to be complemented with run-time CPU family
30 # detection. Oh! It should also be noted that unlike other PowerPC
31 # implementation IALU ppc-mont.pl module performs *suboptimaly* on
32 # >=1024-bit key lengths on Power 6. It should also be noted that
33 # *everything* said so far applies to 64-bit builds! As far as 32-bit
34 # application executed on 64-bit CPU goes, this module is likely to
35 # become preferred choice, because it's easy to adapt it for such
36 # case and *is* faster than 32-bit ppc-mont.pl on *all* processors.
40 # Micro-profiling assisted optimization results in ~15% improvement
41 # over original ppc64-mont.pl version, or overall ~50% improvement
42 # over ppc.pl module on Power 6. If compared to ppc-mont.pl on same
43 # Power 6 CPU, this module is 5-150% faster depending on key length,
44 # [hereafter] more for longer keys. But if compared to ppc-mont.pl
45 # on 1.8GHz PPC970, it's only 5-55% faster. Still far from impressive
46 # in absolute terms, but it's apparently the way Power 6 is...
50 if ($flavour =~ /32/) {
53 $FRAME= $SIZE_T*12+8*12;
54 $fname= "bn_mul_mont_ppc64";
56 $STUX= "stwux"; # store indexed and update
59 die "not implemented yet";
60 } elsif ($flavour =~ /64/) {
63 $FRAME= $SIZE_T*12+8*12;
64 $fname= "bn_mul_mont";
66 # same as above, but 64-bit mnemonics...
67 $STUX= "stdux"; # store indexed and update
70 } else { die "nonsense $flavour"; }
72 $0 =~ m/(.*[\/\\])[^\/\\]+$/; $dir=$1;
73 ( $xlate="${dir}ppc-xlate.pl" and -f $xlate ) or
74 ( $xlate="${dir}../../perlasm/ppc-xlate.pl" and -f $xlate) or
75 die "can't locate ppc-xlate.pl";
77 open STDOUT,"| $^X $xlate $flavour ".shift || die "can't call $xlate: $!";
79 $FRAME=($FRAME+63)&~63;
91 $rp="r9"; # $rp is reassigned
95 # non-volatile registers
96 $nap_d="r14"; # interleaved ap and np in double format
98 $t0="r16"; # temporary registers
107 # PPC offers enough register bank capacity to unroll inner loops twice
131 $ba="f0"; $bb="f1"; $bc="f2"; $bd="f3";
132 $na="f4"; $nb="f5"; $nc="f6"; $nd="f7";
133 $dota="f8"; $dotb="f9";
134 $A0="f10"; $A1="f11"; $A2="f12"; $A3="f13";
135 $N0="f14"; $N1="f15"; $N2="f16"; $N3="f17";
136 $T0a="f18"; $T0b="f19";
137 $T1a="f20"; $T1b="f21";
138 $T2a="f22"; $T2b="f23";
139 $T3a="f24"; $T3b="f25";
141 # sp----------->+-------------------------------+
143 # +-------------------------------+
145 # +-------------------------------+
146 # | 10 saved gpr, r14-r23 |
149 # +12*size_t +-------------------------------+
150 # | 12 saved fpr, f14-f25 |
153 # +12*8 +-------------------------------+
154 # | padding to 64 byte boundary |
156 # +X +-------------------------------+
157 # | 16 gpr<->fpr transfer zone |
160 # +16*8 +-------------------------------+
161 # | __int64 tmp[-1] |
162 # +-------------------------------+
163 # | __int64 tmp[num] |
167 # +(num+1)*8 +-------------------------------+
168 # | padding to 64 byte boundary |
170 # +X +-------------------------------+
171 # | double nap_d[4*num] |
175 # +-------------------------------+
185 mr $rp,r3 ; $rp is reassigned
186 li r3,0 ; possible "not handled" return code
188 andi. r0,$num,1 ; $num has to be even
191 slwi $num,$num,3 ; num*=8
193 slwi $tp,$num,2 ; place for {an}p_{lh}[num], i.e. 4*num
194 add $tp,$tp,$num ; place for tp[num+1]
195 addi $tp,$tp,`$FRAME+$TRANSFER+8+64+$RZONE`
196 subf $tp,$tp,$sp ; $sp-$tp
197 and $tp,$tp,$i ; minimize TLB usage
198 subf $tp,$sp,$tp ; $tp-$sp
199 $STUX $sp,$sp,$tp ; alloca
201 $PUSH r14,`2*$SIZE_T`($sp)
202 $PUSH r15,`3*$SIZE_T`($sp)
203 $PUSH r16,`4*$SIZE_T`($sp)
204 $PUSH r17,`5*$SIZE_T`($sp)
205 $PUSH r18,`6*$SIZE_T`($sp)
206 $PUSH r19,`7*$SIZE_T`($sp)
207 $PUSH r20,`8*$SIZE_T`($sp)
208 $PUSH r21,`9*$SIZE_T`($sp)
209 $PUSH r22,`10*$SIZE_T`($sp)
210 $PUSH r23,`11*$SIZE_T`($sp)
211 stfd f14,`12*$SIZE_T+0`($sp)
212 stfd f15,`12*$SIZE_T+8`($sp)
213 stfd f16,`12*$SIZE_T+16`($sp)
214 stfd f17,`12*$SIZE_T+24`($sp)
215 stfd f18,`12*$SIZE_T+32`($sp)
216 stfd f19,`12*$SIZE_T+40`($sp)
217 stfd f20,`12*$SIZE_T+48`($sp)
218 stfd f21,`12*$SIZE_T+56`($sp)
219 stfd f22,`12*$SIZE_T+64`($sp)
220 stfd f23,`12*$SIZE_T+72`($sp)
221 stfd f24,`12*$SIZE_T+80`($sp)
222 stfd f25,`12*$SIZE_T+88`($sp)
224 ld $a0,0($ap) ; pull ap[0] value
225 ld $n0,0($n0) ; pull n0[0] value
226 ld $t3,0($bp) ; bp[0]
228 addi $tp,$sp,`$FRAME+$TRANSFER+8+64`
231 and $nap_d,$nap_d,$i ; align to 64 bytes
233 mulld $t7,$a0,$t3 ; ap[0]*bp[0]
234 ; nap_d is off by 1, because it's used with stfdu/lfdu
235 addi $nap_d,$nap_d,-8
236 srwi $j,$num,`3+1` ; counter register, num/2
237 mulld $t7,$t7,$n0 ; tp[0]*n0
239 addi $tp,$sp,`$FRAME+$TRANSFER-8`
243 ; transfer bp[0] to FPU as 4x16-bit values
248 std $t0,`$FRAME+0`($sp)
249 std $t1,`$FRAME+8`($sp)
250 std $t2,`$FRAME+16`($sp)
251 std $t3,`$FRAME+24`($sp)
252 ; transfer (ap[0]*bp[0])*n0 to FPU as 4x16-bit values
257 std $t4,`$FRAME+32`($sp)
258 std $t5,`$FRAME+40`($sp)
259 std $t6,`$FRAME+48`($sp)
260 std $t7,`$FRAME+56`($sp)
261 lwz $t0,4($ap) ; load a[j] as 32-bit word pair
263 lwz $t2,12($ap) ; load a[j+1] as 32-bit word pair
265 lwz $t4,4($np) ; load n[j] as 32-bit word pair
267 lwz $t6,12($np) ; load n[j+1] as 32-bit word pair
269 lfd $ba,`$FRAME+0`($sp)
270 lfd $bb,`$FRAME+8`($sp)
271 lfd $bc,`$FRAME+16`($sp)
272 lfd $bd,`$FRAME+24`($sp)
273 lfd $na,`$FRAME+32`($sp)
274 lfd $nb,`$FRAME+40`($sp)
275 lfd $nc,`$FRAME+48`($sp)
276 lfd $nd,`$FRAME+56`($sp)
277 std $t0,`$FRAME+64`($sp)
278 std $t1,`$FRAME+72`($sp)
279 std $t2,`$FRAME+80`($sp)
280 std $t3,`$FRAME+88`($sp)
281 std $t4,`$FRAME+96`($sp)
282 std $t5,`$FRAME+104`($sp)
283 std $t6,`$FRAME+112`($sp)
284 std $t7,`$FRAME+120`($sp)
294 lfd $A0,`$FRAME+64`($sp)
295 lfd $A1,`$FRAME+72`($sp)
296 lfd $A2,`$FRAME+80`($sp)
297 lfd $A3,`$FRAME+88`($sp)
298 lfd $N0,`$FRAME+96`($sp)
299 lfd $N1,`$FRAME+104`($sp)
300 lfd $N2,`$FRAME+112`($sp)
301 lfd $N3,`$FRAME+120`($sp)
315 stfd $A0,8($nap_d) ; save a[j] in double format
319 stfd $A2,24($nap_d) ; save a[j+1] in double format
323 stfd $N0,40($nap_d) ; save n[j] in double format
327 stfd $N2,56($nap_d) ; save n[j+1] in double format
330 fmadd $T1a,$A0,$bc,$T1a
331 fmadd $T1b,$A0,$bd,$T1b
332 fmadd $T2a,$A1,$bc,$T2a
333 fmadd $T2b,$A1,$bd,$T2b
334 fmadd $T3a,$A2,$bc,$T3a
335 fmadd $T3b,$A2,$bd,$T3b
339 fmadd $T1a,$N1,$na,$T1a
340 fmadd $T1b,$N1,$nb,$T1b
341 fmadd $T2a,$N2,$na,$T2a
342 fmadd $T2b,$N2,$nb,$T2b
343 fmadd $T3a,$N3,$na,$T3a
344 fmadd $T3b,$N3,$nb,$T3b
345 fmadd $T0a,$N0,$na,$T0a
346 fmadd $T0b,$N0,$nb,$T0b
348 fmadd $T1a,$N0,$nc,$T1a
349 fmadd $T1b,$N0,$nd,$T1b
350 fmadd $T2a,$N1,$nc,$T2a
351 fmadd $T2b,$N1,$nd,$T2b
352 fmadd $T3a,$N2,$nc,$T3a
353 fmadd $T3b,$N2,$nd,$T3b
354 fmadd $dota,$N3,$nc,$dota
355 fmadd $dotb,$N3,$nd,$dotb
366 stfd $T0a,`$FRAME+0`($sp)
367 stfd $T0b,`$FRAME+8`($sp)
368 stfd $T1a,`$FRAME+16`($sp)
369 stfd $T1b,`$FRAME+24`($sp)
370 stfd $T2a,`$FRAME+32`($sp)
371 stfd $T2b,`$FRAME+40`($sp)
372 stfd $T3a,`$FRAME+48`($sp)
373 stfd $T3b,`$FRAME+56`($sp)
377 lwz $t0,4($ap) ; load a[j] as 32-bit word pair
379 lwz $t2,12($ap) ; load a[j+1] as 32-bit word pair
381 lwz $t4,4($np) ; load n[j] as 32-bit word pair
383 lwz $t6,12($np) ; load n[j+1] as 32-bit word pair
385 std $t0,`$FRAME+64`($sp)
386 std $t1,`$FRAME+72`($sp)
387 std $t2,`$FRAME+80`($sp)
388 std $t3,`$FRAME+88`($sp)
389 std $t4,`$FRAME+96`($sp)
390 std $t5,`$FRAME+104`($sp)
391 std $t6,`$FRAME+112`($sp)
392 std $t7,`$FRAME+120`($sp)
393 ld $t0,`$FRAME+0`($sp)
394 ld $t1,`$FRAME+8`($sp)
395 ld $t2,`$FRAME+16`($sp)
396 ld $t3,`$FRAME+24`($sp)
397 ld $t4,`$FRAME+32`($sp)
398 ld $t5,`$FRAME+40`($sp)
399 ld $t6,`$FRAME+48`($sp)
400 ld $t7,`$FRAME+56`($sp)
401 lfd $A0,`$FRAME+64`($sp)
402 lfd $A1,`$FRAME+72`($sp)
403 lfd $A2,`$FRAME+80`($sp)
404 lfd $A3,`$FRAME+88`($sp)
405 lfd $N0,`$FRAME+96`($sp)
406 lfd $N1,`$FRAME+104`($sp)
407 lfd $N2,`$FRAME+112`($sp)
408 lfd $N3,`$FRAME+120`($sp)
424 stfd $A0,8($nap_d) ; save a[j] in double format
428 fmadd $T0a,$A0,$ba,$dota
429 fmadd $T0b,$A0,$bb,$dotb
430 stfd $A2,24($nap_d) ; save a[j+1] in double format
433 fmadd $T1a,$A0,$bc,$T1a
434 fmadd $T1b,$A0,$bd,$T1b
435 fmadd $T2a,$A1,$bc,$T2a
436 fmadd $T2b,$A1,$bd,$T2b
437 stfd $N0,40($nap_d) ; save n[j] in double format
439 fmadd $T3a,$A2,$bc,$T3a
440 fmadd $T3b,$A2,$bd,$T3b
441 add $t0,$t0,$carry ; can not overflow
444 stfd $N2,56($nap_d) ; save n[j+1] in double format
450 fmadd $T1a,$N1,$na,$T1a
451 fmadd $T1b,$N1,$nb,$T1b
453 fmadd $T2a,$N2,$na,$T2a
454 fmadd $T2b,$N2,$nb,$T2b
456 fmadd $T3a,$N3,$na,$T3a
457 fmadd $T3b,$N3,$nb,$T3b
459 fmadd $T0a,$N0,$na,$T0a
460 fmadd $T0b,$N0,$nb,$T0b
465 fmadd $T1a,$N0,$nc,$T1a
466 fmadd $T1b,$N0,$nd,$T1b
467 insrdi $t0,$t3,16,0 ; 0..63 bits
468 fmadd $T2a,$N1,$nc,$T2a
469 fmadd $T2b,$N1,$nd,$T2b
471 fmadd $T3a,$N2,$nc,$T3a
472 fmadd $T3b,$N2,$nd,$T3b
474 fmadd $dota,$N3,$nc,$dota
475 fmadd $dotb,$N3,$nd,$dotb
492 insrdi $t4,$t7,16,0 ; 64..127 bits
493 srdi $carry,$t7,16 ; upper 33 bits
495 stfd $T0a,`$FRAME+0`($sp)
496 stfd $T0b,`$FRAME+8`($sp)
497 stfd $T1a,`$FRAME+16`($sp)
498 stfd $T1b,`$FRAME+24`($sp)
499 stfd $T2a,`$FRAME+32`($sp)
500 stfd $T2b,`$FRAME+40`($sp)
501 stfd $T3a,`$FRAME+48`($sp)
502 stfd $T3b,`$FRAME+56`($sp)
503 std $t0,8($tp) ; tp[j-1]
504 stdu $t4,16($tp) ; tp[j]
510 ld $t0,`$FRAME+0`($sp)
511 ld $t1,`$FRAME+8`($sp)
512 ld $t2,`$FRAME+16`($sp)
513 ld $t3,`$FRAME+24`($sp)
514 ld $t4,`$FRAME+32`($sp)
515 ld $t5,`$FRAME+40`($sp)
516 ld $t6,`$FRAME+48`($sp)
517 ld $t7,`$FRAME+56`($sp)
518 stfd $dota,`$FRAME+64`($sp)
519 stfd $dotb,`$FRAME+72`($sp)
521 add $t0,$t0,$carry ; can not overflow
531 insrdi $t0,$t3,16,0 ; 0..63 bits
541 insrdi $t4,$t7,16,0 ; 64..127 bits
542 srdi $carry,$t7,16 ; upper 33 bits
543 ld $t6,`$FRAME+64`($sp)
544 ld $t7,`$FRAME+72`($sp)
546 std $t0,8($tp) ; tp[j-1]
547 stdu $t4,16($tp) ; tp[j]
549 add $t6,$t6,$carry ; can not overflow
554 std $t6,8($tp) ; tp[num-1]
557 subf $nap_d,$t7,$nap_d ; rewind pointer
562 ldx $t3,$bp,$i ; bp[i]
563 ld $t6,`$FRAME+$TRANSFER+8`($sp) ; tp[0]
564 mulld $t7,$a0,$t3 ; ap[0]*bp[i]
566 addi $tp,$sp,`$FRAME+$TRANSFER`
567 add $t7,$t7,$t6 ; ap[0]*bp[i]+tp[0]
569 mulld $t7,$t7,$n0 ; tp[0]*n0
572 ; transfer bp[i] to FPU as 4x16-bit values
577 std $t0,`$FRAME+0`($sp)
578 std $t1,`$FRAME+8`($sp)
579 std $t2,`$FRAME+16`($sp)
580 std $t3,`$FRAME+24`($sp)
581 ; transfer (ap[0]*bp[i]+tp[0])*n0 to FPU as 4x16-bit values
586 std $t4,`$FRAME+32`($sp)
587 std $t5,`$FRAME+40`($sp)
588 std $t6,`$FRAME+48`($sp)
589 std $t7,`$FRAME+56`($sp)
591 lfd $A0,8($nap_d) ; load a[j] in double format
593 lfd $A2,24($nap_d) ; load a[j+1] in double format
595 lfd $N0,40($nap_d) ; load n[j] in double format
597 lfd $N2,56($nap_d) ; load n[j+1] in double format
600 lfd $ba,`$FRAME+0`($sp)
601 lfd $bb,`$FRAME+8`($sp)
602 lfd $bc,`$FRAME+16`($sp)
603 lfd $bd,`$FRAME+24`($sp)
604 lfd $na,`$FRAME+32`($sp)
605 lfd $nb,`$FRAME+40`($sp)
606 lfd $nc,`$FRAME+48`($sp)
607 lfd $nd,`$FRAME+56`($sp)
627 fmadd $T1a,$A0,$bc,$T1a
628 fmadd $T1b,$A0,$bd,$T1b
629 fmadd $T2a,$A1,$bc,$T2a
630 fmadd $T2b,$A1,$bd,$T2b
631 fmadd $T3a,$A2,$bc,$T3a
632 fmadd $T3b,$A2,$bd,$T3b
636 fmadd $T1a,$N1,$na,$T1a
637 fmadd $T1b,$N1,$nb,$T1b
638 lfd $A0,8($nap_d) ; load a[j] in double format
640 fmadd $T2a,$N2,$na,$T2a
641 fmadd $T2b,$N2,$nb,$T2b
642 lfd $A2,24($nap_d) ; load a[j+1] in double format
644 fmadd $T3a,$N3,$na,$T3a
645 fmadd $T3b,$N3,$nb,$T3b
646 fmadd $T0a,$N0,$na,$T0a
647 fmadd $T0b,$N0,$nb,$T0b
649 fmadd $T1a,$N0,$nc,$T1a
650 fmadd $T1b,$N0,$nd,$T1b
651 fmadd $T2a,$N1,$nc,$T2a
652 fmadd $T2b,$N1,$nd,$T2b
653 fmadd $T3a,$N2,$nc,$T3a
654 fmadd $T3b,$N2,$nd,$T3b
655 fmadd $dota,$N3,$nc,$dota
656 fmadd $dotb,$N3,$nd,$dotb
667 stfd $T0a,`$FRAME+0`($sp)
668 stfd $T0b,`$FRAME+8`($sp)
669 stfd $T1a,`$FRAME+16`($sp)
670 stfd $T1b,`$FRAME+24`($sp)
671 stfd $T2a,`$FRAME+32`($sp)
672 stfd $T2b,`$FRAME+40`($sp)
673 stfd $T3a,`$FRAME+48`($sp)
674 stfd $T3b,`$FRAME+56`($sp)
682 lfd $N0,40($nap_d) ; load n[j] in double format
686 fmadd $T0a,$A0,$ba,$dota
687 fmadd $T0b,$A0,$bb,$dotb
688 lfd $N2,56($nap_d) ; load n[j+1] in double format
691 fmadd $T1a,$A0,$bc,$T1a
692 fmadd $T1b,$A0,$bd,$T1b
693 fmadd $T2a,$A1,$bc,$T2a
694 fmadd $T2b,$A1,$bd,$T2b
695 lfd $A0,8($nap_d) ; load a[j] in double format
697 fmadd $T3a,$A2,$bc,$T3a
698 fmadd $T3b,$A2,$bd,$T3b
701 lfd $A2,24($nap_d) ; load a[j+1] in double format
704 fmadd $T1a,$N1,$na,$T1a
705 fmadd $T1b,$N1,$nb,$T1b
706 ld $t0,`$FRAME+0`($sp)
707 ld $t1,`$FRAME+8`($sp)
708 fmadd $T2a,$N2,$na,$T2a
709 fmadd $T2b,$N2,$nb,$T2b
710 ld $t2,`$FRAME+16`($sp)
711 ld $t3,`$FRAME+24`($sp)
712 fmadd $T3a,$N3,$na,$T3a
713 fmadd $T3b,$N3,$nb,$T3b
714 add $t0,$t0,$carry ; can not overflow
715 ld $t4,`$FRAME+32`($sp)
716 ld $t5,`$FRAME+40`($sp)
717 fmadd $T0a,$N0,$na,$T0a
718 fmadd $T0b,$N0,$nb,$T0b
722 ld $t6,`$FRAME+48`($sp)
723 ld $t7,`$FRAME+56`($sp)
725 fmadd $T1a,$N0,$nc,$T1a
726 fmadd $T1b,$N0,$nd,$T1b
728 ld $t1,8($tp) ; tp[j]
729 fmadd $T2a,$N1,$nc,$T2a
730 fmadd $T2b,$N1,$nd,$T2b
732 fmadd $T3a,$N2,$nc,$T3a
733 fmadd $T3b,$N2,$nd,$T3b
736 fmadd $dota,$N3,$nc,$dota
737 fmadd $dotb,$N3,$nd,$dotb
739 ldu $t2,16($tp) ; tp[j+1]
741 insrdi $t0,$t3,16,0 ; 0..63 bits
760 stfd $T0a,`$FRAME+0`($sp)
761 stfd $T0b,`$FRAME+8`($sp)
764 stfd $T1a,`$FRAME+16`($sp)
765 stfd $T1b,`$FRAME+24`($sp)
766 insrdi $t4,$t7,16,0 ; 64..127 bits
767 srdi $carry,$t7,16 ; upper 33 bits
768 stfd $T2a,`$FRAME+32`($sp)
769 stfd $T2b,`$FRAME+40`($sp)
771 stfd $T3a,`$FRAME+48`($sp)
772 stfd $T3b,`$FRAME+56`($sp)
774 std $t3,-16($tp) ; tp[j-1]
775 std $t5,-8($tp) ; tp[j]
780 ld $t0,`$FRAME+0`($sp)
781 ld $t1,`$FRAME+8`($sp)
782 ld $t2,`$FRAME+16`($sp)
783 ld $t3,`$FRAME+24`($sp)
784 ld $t4,`$FRAME+32`($sp)
785 ld $t5,`$FRAME+40`($sp)
786 ld $t6,`$FRAME+48`($sp)
787 ld $t7,`$FRAME+56`($sp)
788 stfd $dota,`$FRAME+64`($sp)
789 stfd $dotb,`$FRAME+72`($sp)
791 add $t0,$t0,$carry ; can not overflow
797 ld $t1,8($tp) ; tp[j]
801 ldu $t2,16($tp) ; tp[j+1]
803 insrdi $t0,$t3,16,0 ; 0..63 bits
813 insrdi $t4,$t7,16,0 ; 64..127 bits
814 srdi $carry,$t7,16 ; upper 33 bits
815 ld $t6,`$FRAME+64`($sp)
816 ld $t7,`$FRAME+72`($sp)
822 std $t3,-16($tp) ; tp[j-1]
823 std $t5,-8($tp) ; tp[j]
825 add $carry,$carry,$ovf ; comsume upmost overflow
826 add $t6,$t6,$carry ; can not overflow
831 std $t6,0($tp) ; tp[num-1]
835 subf $nap_d,$t7,$nap_d ; rewind pointer
839 subf $np,$num,$np ; rewind np
840 addi $j,$j,1 ; restore counter
841 subfc $i,$i,$i ; j=0 and "clear" XER[CA]
842 addi $tp,$sp,`$FRAME+$TRANSFER+8`
843 addi $t4,$sp,`$FRAME+$TRANSFER+16`
853 subfe $t0,$t1,$t0 ; tp[j]-np[j]
854 subfe $t2,$t3,$t2 ; tp[j+1]-np[j+1]
861 subfe $ovf,$i,$ovf ; handle upmost overflow bit
864 or $ap,$ap,$np ; ap=borrow?tp:rp
869 Lcopy: ; copy or in-place refresh
872 std $i,8($nap_d) ; zap nap_d
882 stdx $i,$tp,$i ; zap tp at once
887 $POP r14,`2*$SIZE_T`($sp)
888 $POP r15,`3*$SIZE_T`($sp)
889 $POP r16,`4*$SIZE_T`($sp)
890 $POP r17,`5*$SIZE_T`($sp)
891 $POP r18,`6*$SIZE_T`($sp)
892 $POP r19,`7*$SIZE_T`($sp)
893 $POP r20,`8*$SIZE_T`($sp)
894 $POP r21,`9*$SIZE_T`($sp)
895 $POP r22,`10*$SIZE_T`($sp)
896 $POP r23,`11*$SIZE_T`($sp)
897 lfd f14,`12*$SIZE_T+0`($sp)
898 lfd f15,`12*$SIZE_T+8`($sp)
899 lfd f16,`12*$SIZE_T+16`($sp)
900 lfd f17,`12*$SIZE_T+24`($sp)
901 lfd f18,`12*$SIZE_T+32`($sp)
902 lfd f19,`12*$SIZE_T+40`($sp)
903 lfd f20,`12*$SIZE_T+48`($sp)
904 lfd f21,`12*$SIZE_T+56`($sp)
905 lfd f22,`12*$SIZE_T+64`($sp)
906 lfd f23,`12*$SIZE_T+72`($sp)
907 lfd f24,`12*$SIZE_T+80`($sp)
908 lfd f25,`12*$SIZE_T+88`($sp)
910 li r3,1 ; signal "handled"
913 .asciz "Montgomery Multiplication for PPC64, CRYPTOGAMS by <appro\@fy.chalmers.se>"
916 $code =~ s/\`([^\`]*)\`/eval $1/gem;