3 # ====================================================================
4 # Written by Andy Polyakov <appro@openssl.org> 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 # Montgomery multiplication for ARMv4.
14 # Performance improvement naturally varies among CPU implementations
15 # and compilers. The code was observed to provide +65-35% improvement
16 # [depending on key length, less for longer keys] on ARM920T, and
17 # +115-80% on Intel IXP425. This is compared to pre-bn_mul_mont code
18 # base and compiler generated code with in-lined umull and even umlal
19 # instructions. The latter means that this code didn't really have an
20 # "advantage" of utilizing some "secret" instruction.
22 # The code is interoperable with Thumb ISA and is rather compact, less
23 # than 1/2KB. Windows CE port would be trivial, as it's exclusively
24 # about decorations, ABI and instruction syntax are identical.
28 # Add NEON code path, which handles lengths divisible by 8. RSA/DSA
29 # performance improvement on Cortex-A8 is ~45-100% depending on key
30 # length, more for longer keys. On Cortex-A15 the span is ~10-105%.
31 # On Snapdragon S4 improvement was measured to vary from ~70% to
32 # incredible ~380%, yes, 4.8x faster, for RSA4096 sign. But this is
33 # rather because original integer-only code seems to perform
34 # suboptimally on S4. Situation on Cortex-A9 is unfortunately
35 # different. It's being looked into, but the trouble is that
36 # performance for vectors longer than 256 bits is actually couple
37 # of percent worse than for integer-only code. The code is chosen
38 # for execution on all NEON-capable processors, because gain on
39 # others outweighs the marginal loss on Cortex-A9.
41 while (($output=shift) && ($output!~/^\w[\w\-]*\.\w+$/)) {}
42 open STDOUT,">$output";
44 $num="r0"; # starts as num argument, but holds &tp[num-1]
46 $bp="r2"; $bi="r2"; $rp="r2";
53 ########### # r9 is reserved by ELF as platform specific, e.g. TLS pointer
54 $alo="r10"; # sl, gcc uses it to keep @GOT
57 ########### # r13 is stack pointer
59 ########### # r15 is program counter
61 #### argument block layout relative to &tp[num-1], a.k.a. $num
63 # ap permanently resides in r1
65 # np permanently resides in r3
67 $_num="$num,#15*4"; $_bpend=$_num;
75 #if __ARM_MAX_ARCH__>=7
78 .word OPENSSL_armcap_P-bn_mul_mont
82 .type bn_mul_mont,%function
86 ldr ip,[sp,#4] @ load num
87 stmdb sp!,{r0,r2} @ sp points at argument block
88 #if __ARM_MAX_ARCH__>=7
92 ldr r2,.LOPENSSL_armcap
94 tst r0,#1 @ NEON available?
103 mov $num,ip @ load num
108 stmdb sp!,{r4-r12,lr} @ save 10 registers
110 mov $num,$num,lsl#2 @ rescale $num for byte count
111 sub sp,sp,$num @ alloca(4*num)
112 sub sp,sp,#4 @ +extra dword
113 sub $num,$num,#4 @ "num=num-1"
114 add $tp,$bp,$num @ &bp[num-1]
116 add $num,sp,$num @ $num to point at &tp[num-1]
118 ldr $bi,[$bp] @ bp[0]
119 ldr $aj,[$ap],#4 @ ap[0],ap++
120 ldr $nj,[$np],#4 @ np[0],np++
122 str $tp,[$_bpend] @ save &bp[num]
124 umull $alo,$ahi,$aj,$bi @ ap[0]*bp[0]
125 str $n0,[$_n0] @ save n0 value
126 mul $n0,$alo,$n0 @ "tp[0]"*n0
128 umlal $alo,$nlo,$nj,$n0 @ np[0]*n0+"t[0]"
132 ldr $aj,[$ap],#4 @ ap[j],ap++
134 ldr $nj,[$np],#4 @ np[j],np++
136 umlal $alo,$ahi,$aj,$bi @ ap[j]*bp[0]
138 umlal $nlo,$nhi,$nj,$n0 @ np[j]*n0
140 str $nlo,[$tp],#4 @ tp[j-1]=,tp++
146 ldr $tp,[$_bp] @ restore bp
148 ldr $n0,[$_n0] @ restore n0
150 str $nlo,[$num] @ tp[num-1]=
151 str $nhi,[$num,#4] @ tp[num]=
154 sub $tj,$num,sp @ "original" $num-1 value
155 sub $ap,$ap,$tj @ "rewind" ap to &ap[1]
156 ldr $bi,[$tp,#4]! @ *(++bp)
157 sub $np,$np,$tj @ "rewind" np to &np[1]
158 ldr $aj,[$ap,#-4] @ ap[0]
159 ldr $alo,[sp] @ tp[0]
160 ldr $nj,[$np,#-4] @ np[0]
161 ldr $tj,[sp,#4] @ tp[1]
164 umlal $alo,$ahi,$aj,$bi @ ap[0]*bp[i]+tp[0]
165 str $tp,[$_bp] @ save bp
168 umlal $alo,$nlo,$nj,$n0 @ np[0]*n0+"tp[0]"
172 ldr $aj,[$ap],#4 @ ap[j],ap++
173 adds $alo,$ahi,$tj @ +=tp[j]
174 ldr $nj,[$np],#4 @ np[j],np++
176 umlal $alo,$ahi,$aj,$bi @ ap[j]*bp[i]
178 umlal $nlo,$nhi,$nj,$n0 @ np[j]*n0
180 ldr $tj,[$tp,#8] @ tp[j+1]
182 str $nlo,[$tp],#4 @ tp[j-1]=,tp++
189 ldr $tp,[$_bp] @ restore bp
191 ldr $n0,[$_n0] @ restore n0
193 ldr $tj,[$_bpend] @ restore &bp[num]
195 str $nlo,[$num] @ tp[num-1]=
196 str $nhi,[$num,#4] @ tp[num]=
201 ldr $rp,[$_rp] @ pull rp
202 add $num,$num,#4 @ $num to point at &tp[num]
203 sub $aj,$num,sp @ "original" num value
204 mov $tp,sp @ "rewind" $tp
205 mov $ap,$tp @ "borrow" $ap
206 sub $np,$np,$aj @ "rewind" $np to &np[0]
208 subs $tj,$tj,$tj @ "clear" carry flag
209 .Lsub: ldr $tj,[$tp],#4
211 sbcs $tj,$tj,$nj @ tp[j]-np[j]
212 str $tj,[$rp],#4 @ rp[j]=
213 teq $tp,$num @ preserve carry
215 sbcs $nhi,$nhi,#0 @ upmost carry
216 mov $tp,sp @ "rewind" $tp
217 sub $rp,$rp,$aj @ "rewind" $rp
219 .Lcopy: ldr $tj,[$tp] @ conditional copy
221 str sp,[$tp],#4 @ zap tp
227 teq $tp,$num @ preserve carry
230 add sp,$num,#4 @ skip over tp[num+1]
231 ldmia sp!,{r4-r12,lr} @ restore registers
232 add sp,sp,#2*4 @ skip over {r0,r2}
239 moveq pc,lr @ be binary compatible with V4, yet
240 bx lr @ interoperable with Thumb ISA:-)
242 .size bn_mul_mont,.-bn_mul_mont
245 sub Dlo() { shift=~m|q([1]?[0-9])|?"d".($1*2):""; }
246 sub Dhi() { shift=~m|q([1]?[0-9])|?"d".($1*2+1):""; }
248 my ($A0,$A1,$A2,$A3)=map("d$_",(0..3));
249 my ($N0,$N1,$N2,$N3)=map("d$_",(4..7));
250 my ($Z,$Temp)=("q4","q5");
251 my ($A0xB,$A1xB,$A2xB,$A3xB,$A4xB,$A5xB,$A6xB,$A7xB)=map("q$_",(6..13));
252 my ($Bi,$Ni,$M0)=map("d$_",(28..31));
254 my $temp=&Dlo($Temp);
256 my ($rptr,$aptr,$bptr,$nptr,$n0,$num)=map("r$_",(0..5));
257 my ($tinptr,$toutptr,$inner,$outer)=map("r$_",(6..9));
260 #if __ARM_MAX_ARCH__>=7
264 .type bn_mul8x_mont_neon,%function
269 vstmdb sp!,{d8-d15} @ ABI specification says so
270 ldmia ip,{r4-r5} @ load rest of parameter block
273 vld1.32 {${Bi}[0]}, [$bptr,:32]!
274 sub $toutptr,$toutptr,$num,lsl#4
275 vld1.32 {$A0-$A3}, [$aptr]! @ can't specify :32 :-(
276 and $toutptr,$toutptr,#-64
277 vld1.32 {${M0}[0]}, [$n0,:32]
278 mov sp,$toutptr @ alloca
279 veor $zero,$zero,$zero
283 vmull.u32 $A0xB,$Bi,${A0}[0]
284 vmull.u32 $A1xB,$Bi,${A0}[1]
285 vmull.u32 $A2xB,$Bi,${A1}[0]
286 vshl.i64 $temp,`&Dhi("$A0xB")`,#16
287 vmull.u32 $A3xB,$Bi,${A1}[1]
289 vadd.u64 $temp,$temp,`&Dlo("$A0xB")`
290 veor $zero,$zero,$zero
291 vmul.u32 $Ni,$temp,$M0
293 vmull.u32 $A4xB,$Bi,${A2}[0]
294 vld1.32 {$N0-$N3}, [$nptr]!
295 vmull.u32 $A5xB,$Bi,${A2}[1]
296 vmull.u32 $A6xB,$Bi,${A3}[0]
298 vmull.u32 $A7xB,$Bi,${A3}[1]
302 @ special case for num=8, everything is in register bank...
304 vmlal.u32 $A0xB,$Ni,${N0}[0]
306 vmlal.u32 $A1xB,$Ni,${N0}[1]
307 vmlal.u32 $A2xB,$Ni,${N1}[0]
308 vmlal.u32 $A3xB,$Ni,${N1}[1]
310 vmlal.u32 $A4xB,$Ni,${N2}[0]
312 vmlal.u32 $A5xB,$Ni,${N2}[1]
314 vmlal.u32 $A6xB,$Ni,${N3}[0]
316 vmlal.u32 $A7xB,$Ni,${N3}[1]
319 vshr.u64 $temp,$temp,#16
322 vadd.u64 $temp,$temp,`&Dhi("$Temp")`
325 vshr.u64 $temp,$temp,#16
331 vld1.32 {${Bi}[0]}, [$bptr,:32]!
332 veor $zero,$zero,$zero
334 vadd.u64 `&Dlo("$A0xB")`,`&Dlo("$A0xB")`,$temp
336 vmlal.u32 $A0xB,$Bi,${A0}[0]
337 vmlal.u32 $A1xB,$Bi,${A0}[1]
338 vmlal.u32 $A2xB,$Bi,${A1}[0]
339 vshl.i64 $temp,`&Dhi("$A0xB")`,#16
340 vmlal.u32 $A3xB,$Bi,${A1}[1]
342 vadd.u64 $temp,$temp,`&Dlo("$A0xB")`
343 veor $zero,$zero,$zero
344 subs $outer,$outer,#1
345 vmul.u32 $Ni,$temp,$M0
347 vmlal.u32 $A4xB,$Bi,${A2}[0]
348 vmlal.u32 $A5xB,$Bi,${A2}[1]
349 vmlal.u32 $A6xB,$Bi,${A3}[0]
351 vmlal.u32 $A7xB,$Bi,${A3}[1]
353 vmlal.u32 $A0xB,$Ni,${N0}[0]
354 vmlal.u32 $A1xB,$Ni,${N0}[1]
355 vmlal.u32 $A2xB,$Ni,${N1}[0]
356 vmlal.u32 $A3xB,$Ni,${N1}[1]
358 vmlal.u32 $A4xB,$Ni,${N2}[0]
360 vmlal.u32 $A5xB,$Ni,${N2}[1]
362 vmlal.u32 $A6xB,$Ni,${N3}[0]
364 vmlal.u32 $A7xB,$Ni,${N3}[1]
367 vshr.u64 $temp,$temp,#16
370 vadd.u64 $temp,$temp,`&Dhi("$Temp")`
373 vshr.u64 $temp,$temp,#16
377 vadd.u64 `&Dlo("$A0xB")`,`&Dlo("$A0xB")`,$temp
379 vshr.u64 $temp,`&Dlo("$A0xB")`,#16
381 vadd.u64 `&Dhi("$A0xB")`,`&Dhi("$A0xB")`,$temp
383 vshr.u64 $temp,`&Dhi("$A0xB")`,#16
384 vzip.16 `&Dlo("$A0xB")`,`&Dhi("$A0xB")`
390 vmlal.u32 $A0xB,$Ni,${N0}[0]
391 vld1.32 {$A0-$A3}, [$aptr]!
392 vmlal.u32 $A1xB,$Ni,${N0}[1]
393 subs $inner,$inner,#8
394 vmlal.u32 $A2xB,$Ni,${N1}[0]
395 vmlal.u32 $A3xB,$Ni,${N1}[1]
397 vmlal.u32 $A4xB,$Ni,${N2}[0]
398 vld1.32 {$N0-$N1}, [$nptr]!
399 vmlal.u32 $A5xB,$Ni,${N2}[1]
400 vst1.64 {$A0xB-$A1xB}, [$toutptr,:256]!
401 vmlal.u32 $A6xB,$Ni,${N3}[0]
402 vmlal.u32 $A7xB,$Ni,${N3}[1]
403 vst1.64 {$A2xB-$A3xB}, [$toutptr,:256]!
405 vmull.u32 $A0xB,$Bi,${A0}[0]
406 vld1.32 {$N2-$N3}, [$nptr]!
407 vmull.u32 $A1xB,$Bi,${A0}[1]
408 vst1.64 {$A4xB-$A5xB}, [$toutptr,:256]!
409 vmull.u32 $A2xB,$Bi,${A1}[0]
410 vmull.u32 $A3xB,$Bi,${A1}[1]
411 vst1.64 {$A6xB-$A7xB}, [$toutptr,:256]!
413 vmull.u32 $A4xB,$Bi,${A2}[0]
414 vmull.u32 $A5xB,$Bi,${A2}[1]
415 vmull.u32 $A6xB,$Bi,${A3}[0]
416 vmull.u32 $A7xB,$Bi,${A3}[1]
420 vmlal.u32 $A0xB,$Ni,${N0}[0]
422 vmlal.u32 $A1xB,$Ni,${N0}[1]
423 sub $aptr,$aptr,$num,lsl#2 @ rewind $aptr
424 vmlal.u32 $A2xB,$Ni,${N1}[0]
425 vld1.64 {$Temp}, [sp,:128]
426 vmlal.u32 $A3xB,$Ni,${N1}[1]
429 vmlal.u32 $A4xB,$Ni,${N2}[0]
430 vst1.64 {$A0xB-$A1xB}, [$toutptr,:256]!
431 vmlal.u32 $A5xB,$Ni,${N2}[1]
432 vshr.u64 $temp,$temp,#16
433 vld1.64 {$A0xB}, [$tinptr, :128]!
434 vmlal.u32 $A6xB,$Ni,${N3}[0]
435 vst1.64 {$A2xB-$A3xB}, [$toutptr,:256]!
436 vmlal.u32 $A7xB,$Ni,${N3}[1]
438 vst1.64 {$A4xB-$A5xB}, [$toutptr,:256]!
439 vadd.u64 $temp,$temp,`&Dhi("$Temp")`
441 vst1.64 {$A6xB-$A7xB}, [$toutptr,:256]!
442 vld1.64 {$A1xB-$A2xB}, [$tinptr, :256]!
443 vst1.64 {$Z}, [$toutptr,:128]
444 vshr.u64 $temp,$temp,#16
450 vld1.32 {${Bi}[0]}, [$bptr,:32]!
451 sub $nptr,$nptr,$num,lsl#2 @ rewind $nptr
452 vld1.32 {$A0-$A3}, [$aptr]!
453 veor $zero,$zero,$zero
457 vadd.u64 `&Dlo("$A0xB")`,`&Dlo("$A0xB")`,$temp
459 vmlal.u32 $A0xB,$Bi,${A0}[0]
460 vld1.64 {$A3xB-$A4xB},[$tinptr,:256]!
461 vmlal.u32 $A1xB,$Bi,${A0}[1]
462 vmlal.u32 $A2xB,$Bi,${A1}[0]
463 vld1.64 {$A5xB-$A6xB},[$tinptr,:256]!
464 vmlal.u32 $A3xB,$Bi,${A1}[1]
466 vshl.i64 $temp,`&Dhi("$A0xB")`,#16
467 veor $zero,$zero,$zero
468 vadd.u64 $temp,$temp,`&Dlo("$A0xB")`
469 vld1.64 {$A7xB},[$tinptr,:128]!
470 vmul.u32 $Ni,$temp,$M0
472 vmlal.u32 $A4xB,$Bi,${A2}[0]
473 vld1.32 {$N0-$N3}, [$nptr]!
474 vmlal.u32 $A5xB,$Bi,${A2}[1]
475 vmlal.u32 $A6xB,$Bi,${A3}[0]
477 vmlal.u32 $A7xB,$Bi,${A3}[1]
480 vmlal.u32 $A0xB,$Ni,${N0}[0]
481 vld1.32 {$A0-$A3}, [$aptr]!
482 vmlal.u32 $A1xB,$Ni,${N0}[1]
483 subs $inner,$inner,#8
484 vmlal.u32 $A2xB,$Ni,${N1}[0]
485 vmlal.u32 $A3xB,$Ni,${N1}[1]
486 vst1.64 {$A0xB-$A1xB}, [$toutptr,:256]!
488 vmlal.u32 $A4xB,$Ni,${N2}[0]
489 vld1.64 {$A0xB}, [$tinptr, :128]!
490 vmlal.u32 $A5xB,$Ni,${N2}[1]
491 vst1.64 {$A2xB-$A3xB}, [$toutptr,:256]!
492 vmlal.u32 $A6xB,$Ni,${N3}[0]
493 vld1.64 {$A1xB-$A2xB}, [$tinptr, :256]!
494 vmlal.u32 $A7xB,$Ni,${N3}[1]
495 vst1.64 {$A4xB-$A5xB}, [$toutptr,:256]!
497 vmlal.u32 $A0xB,$Bi,${A0}[0]
498 vld1.64 {$A3xB-$A4xB}, [$tinptr, :256]!
499 vmlal.u32 $A1xB,$Bi,${A0}[1]
500 vst1.64 {$A6xB-$A7xB}, [$toutptr,:256]!
501 vmlal.u32 $A2xB,$Bi,${A1}[0]
502 vld1.64 {$A5xB-$A6xB}, [$tinptr, :256]!
503 vmlal.u32 $A3xB,$Bi,${A1}[1]
504 vld1.32 {$N0-$N3}, [$nptr]!
506 vmlal.u32 $A4xB,$Bi,${A2}[0]
507 vld1.64 {$A7xB}, [$tinptr, :128]!
508 vmlal.u32 $A5xB,$Bi,${A2}[1]
509 vmlal.u32 $A6xB,$Bi,${A3}[0]
510 vmlal.u32 $A7xB,$Bi,${A3}[1]
514 vmlal.u32 $A0xB,$Ni,${N0}[0]
516 vmlal.u32 $A1xB,$Ni,${N0}[1]
517 sub $aptr,$aptr,$num,lsl#2 @ rewind $aptr
518 vmlal.u32 $A2xB,$Ni,${N1}[0]
519 vld1.64 {$Temp}, [sp,:128]
520 vmlal.u32 $A3xB,$Ni,${N1}[1]
521 subs $outer,$outer,#1
523 vmlal.u32 $A4xB,$Ni,${N2}[0]
524 vst1.64 {$A0xB-$A1xB}, [$toutptr,:256]!
525 vmlal.u32 $A5xB,$Ni,${N2}[1]
526 vld1.64 {$A0xB}, [$tinptr, :128]!
527 vshr.u64 $temp,$temp,#16
528 vst1.64 {$A2xB-$A3xB}, [$toutptr,:256]!
529 vmlal.u32 $A6xB,$Ni,${N3}[0]
530 vld1.64 {$A1xB-$A2xB}, [$tinptr, :256]!
531 vmlal.u32 $A7xB,$Ni,${N3}[1]
533 vst1.64 {$A4xB-$A5xB}, [$toutptr,:256]!
534 vadd.u64 $temp,$temp,`&Dhi("$Temp")`
535 vst1.64 {$A6xB-$A7xB}, [$toutptr,:256]!
536 vshr.u64 $temp,$temp,#16
544 vadd.u64 `&Dlo("$A0xB")`,`&Dlo("$A0xB")`,$temp
545 vld1.64 {$A3xB-$A4xB}, [$tinptr, :256]!
546 vshr.u64 $temp,`&Dlo("$A0xB")`,#16
547 vadd.u64 `&Dhi("$A0xB")`,`&Dhi("$A0xB")`,$temp
548 vld1.64 {$A5xB-$A6xB}, [$tinptr, :256]!
549 vshr.u64 $temp,`&Dhi("$A0xB")`,#16
550 vld1.64 {$A7xB}, [$tinptr, :128]!
551 vzip.16 `&Dlo("$A0xB")`,`&Dhi("$A0xB")`
554 vadd.u64 `&Dlo("$A1xB")`,`&Dlo("$A1xB")`,$temp
555 vst1.32 {`&Dlo("$A0xB")`[0]}, [$toutptr, :32]!
556 vshr.u64 $temp,`&Dlo("$A1xB")`,#16
557 vadd.u64 `&Dhi("$A1xB")`,`&Dhi("$A1xB")`,$temp
558 vshr.u64 $temp,`&Dhi("$A1xB")`,#16
559 vzip.16 `&Dlo("$A1xB")`,`&Dhi("$A1xB")`
561 vadd.u64 `&Dlo("$A2xB")`,`&Dlo("$A2xB")`,$temp
562 vst1.32 {`&Dlo("$A1xB")`[0]}, [$toutptr, :32]!
563 vshr.u64 $temp,`&Dlo("$A2xB")`,#16
564 vadd.u64 `&Dhi("$A2xB")`,`&Dhi("$A2xB")`,$temp
565 vshr.u64 $temp,`&Dhi("$A2xB")`,#16
566 vzip.16 `&Dlo("$A2xB")`,`&Dhi("$A2xB")`
568 vadd.u64 `&Dlo("$A3xB")`,`&Dlo("$A3xB")`,$temp
569 vst1.32 {`&Dlo("$A2xB")`[0]}, [$toutptr, :32]!
570 vshr.u64 $temp,`&Dlo("$A3xB")`,#16
571 vadd.u64 `&Dhi("$A3xB")`,`&Dhi("$A3xB")`,$temp
572 vshr.u64 $temp,`&Dhi("$A3xB")`,#16
573 vzip.16 `&Dlo("$A3xB")`,`&Dhi("$A3xB")`
575 vadd.u64 `&Dlo("$A4xB")`,`&Dlo("$A4xB")`,$temp
576 vst1.32 {`&Dlo("$A3xB")`[0]}, [$toutptr, :32]!
577 vshr.u64 $temp,`&Dlo("$A4xB")`,#16
578 vadd.u64 `&Dhi("$A4xB")`,`&Dhi("$A4xB")`,$temp
579 vshr.u64 $temp,`&Dhi("$A4xB")`,#16
580 vzip.16 `&Dlo("$A4xB")`,`&Dhi("$A4xB")`
582 vadd.u64 `&Dlo("$A5xB")`,`&Dlo("$A5xB")`,$temp
583 vst1.32 {`&Dlo("$A4xB")`[0]}, [$toutptr, :32]!
584 vshr.u64 $temp,`&Dlo("$A5xB")`,#16
585 vadd.u64 `&Dhi("$A5xB")`,`&Dhi("$A5xB")`,$temp
586 vshr.u64 $temp,`&Dhi("$A5xB")`,#16
587 vzip.16 `&Dlo("$A5xB")`,`&Dhi("$A5xB")`
589 vadd.u64 `&Dlo("$A6xB")`,`&Dlo("$A6xB")`,$temp
590 vst1.32 {`&Dlo("$A5xB")`[0]}, [$toutptr, :32]!
591 vshr.u64 $temp,`&Dlo("$A6xB")`,#16
592 vadd.u64 `&Dhi("$A6xB")`,`&Dhi("$A6xB")`,$temp
593 vld1.64 {$A0xB}, [$tinptr, :128]!
594 vshr.u64 $temp,`&Dhi("$A6xB")`,#16
595 vzip.16 `&Dlo("$A6xB")`,`&Dhi("$A6xB")`
597 vadd.u64 `&Dlo("$A7xB")`,`&Dlo("$A7xB")`,$temp
598 vst1.32 {`&Dlo("$A6xB")`[0]}, [$toutptr, :32]!
599 vshr.u64 $temp,`&Dlo("$A7xB")`,#16
600 vadd.u64 `&Dhi("$A7xB")`,`&Dhi("$A7xB")`,$temp
601 vld1.64 {$A1xB-$A2xB}, [$tinptr, :256]!
602 vshr.u64 $temp,`&Dhi("$A7xB")`,#16
603 vzip.16 `&Dlo("$A7xB")`,`&Dhi("$A7xB")`
604 subs $inner,$inner,#8
605 vst1.32 {`&Dlo("$A7xB")`[0]}, [$toutptr, :32]!
609 vst1.32 {${temp}[0]}, [$toutptr, :32] @ top-most bit
610 sub $nptr,$nptr,$num,lsl#2 @ rewind $nptr
611 subs $aptr,sp,#0 @ clear carry flag
612 add $bptr,sp,$num,lsl#2
615 ldmia $aptr!, {r4-r7}
616 ldmia $nptr!, {r8-r11}
621 teq $aptr,$bptr @ preserves carry
622 stmia $rptr!, {r8-r11}
625 ldr r10, [$aptr] @ load top-most bit
627 sub r11,$bptr,sp @ this is num*4
630 sub $rptr,$rptr,r11 @ rewind $rptr
631 mov $nptr,$bptr @ second 3/4th of frame
632 sbcs r10,r10,#0 @ result is carry flag
635 ldmia $aptr!, {r4-r7}
636 ldmia $rptr, {r8-r11}
638 vst1.64 {q0-q1}, [$nptr,:256]! @ wipe
641 vst1.64 {q0-q1}, [$nptr,:256]! @ wipe
644 stmia $rptr!, {r8-r11}
646 ldmia $rptr, {r8-r11}
648 vst1.64 {q0-q1}, [$aptr,:256]! @ wipe
651 vst1.64 {q0-q1}, [$nptr,:256]! @ wipe
653 teq $aptr,$bptr @ preserves carry
654 stmia $rptr!, {r8-r11}
655 bne .LNEON_copy_n_zap
661 .size bn_mul8x_mont_neon,.-bn_mul8x_mont_neon
666 .asciz "Montgomery multiplication for ARMv4/NEON, CRYPTOGAMS by <appro\@openssl.org>"
668 #if __ARM_MAX_ARCH__>=7
669 .comm OPENSSL_armcap_P,4,4
673 $code =~ s/\`([^\`]*)\`/eval $1/gem;
674 $code =~ s/\bbx\s+lr\b/.word\t0xe12fff1e/gm; # make it possible to compile with -march=armv4
675 $code =~ s/\bret\b/bx lr/gm;