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;
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
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
221 orr $ap,$ap,$np @ ap=borrow?tp:rp
223 .Lcopy: ldr $tj,[$ap],#4 @ copy or in-place refresh
224 str sp,[$tp],#4 @ zap tp
229 add sp,$num,#4 @ skip over tp[num+1]
230 ldmia sp!,{r4-r12,lr} @ restore registers
231 add sp,sp,#2*4 @ skip over {r0,r2}
234 moveq pc,lr @ be binary compatible with V4, yet
235 bx lr @ interoperable with Thumb ISA:-)
236 .size bn_mul_mont,.-bn_mul_mont
239 sub Dlo() { shift=~m|q([1]?[0-9])|?"d".($1*2):""; }
240 sub Dhi() { shift=~m|q([1]?[0-9])|?"d".($1*2+1):""; }
242 my ($A0,$A1,$A2,$A3)=map("d$_",(0..3));
243 my ($N0,$N1,$N2,$N3)=map("d$_",(4..7));
244 my ($Z,$Temp)=("q4","q5");
245 my ($A0xB,$A1xB,$A2xB,$A3xB,$A4xB,$A5xB,$A6xB,$A7xB)=map("q$_",(6..13));
246 my ($Bi,$Ni,$M0)=map("d$_",(28..31));
248 my $temp=&Dlo($Temp);
250 my ($rptr,$aptr,$bptr,$nptr,$n0,$num)=map("r$_",(0..5));
251 my ($tinptr,$toutptr,$inner,$outer)=map("r$_",(6..9));
257 .type bn_mul8x_mont_neon,%function
262 vstmdb sp!,{d8-d15} @ ABI specification says so
263 ldmia ip,{r4-r5} @ load rest of parameter block
266 vld1.32 {${Bi}[0]}, [$bptr,:32]!
267 sub $toutptr,$toutptr,$num,lsl#4
268 vld1.32 {$A0-$A3}, [$aptr]! @ can't specify :32 :-(
269 and $toutptr,$toutptr,#-64
270 vld1.32 {${M0}[0]}, [$n0,:32]
271 mov sp,$toutptr @ alloca
272 veor $zero,$zero,$zero
276 vmull.u32 $A0xB,$Bi,${A0}[0]
277 vmull.u32 $A1xB,$Bi,${A0}[1]
278 vmull.u32 $A2xB,$Bi,${A1}[0]
279 vshl.i64 $temp,`&Dhi("$A0xB")`,#16
280 vmull.u32 $A3xB,$Bi,${A1}[1]
282 vadd.u64 $temp,$temp,`&Dlo("$A0xB")`
283 veor $zero,$zero,$zero
284 vmul.u32 $Ni,$temp,$M0
286 vmull.u32 $A4xB,$Bi,${A2}[0]
287 vld1.32 {$N0-$N3}, [$nptr]!
288 vmull.u32 $A5xB,$Bi,${A2}[1]
289 vmull.u32 $A6xB,$Bi,${A3}[0]
291 vmull.u32 $A7xB,$Bi,${A3}[1]
295 @ special case for num=8, everything is in register bank...
297 vmlal.u32 $A0xB,$Ni,${N0}[0]
299 vmlal.u32 $A1xB,$Ni,${N0}[1]
300 vmlal.u32 $A2xB,$Ni,${N1}[0]
301 vmlal.u32 $A3xB,$Ni,${N1}[1]
303 vmlal.u32 $A4xB,$Ni,${N2}[0]
305 vmlal.u32 $A5xB,$Ni,${N2}[1]
307 vmlal.u32 $A6xB,$Ni,${N3}[0]
309 vmlal.u32 $A7xB,$Ni,${N3}[1]
312 vshr.u64 $temp,$temp,#16
315 vadd.u64 $temp,$temp,`&Dhi("$Temp")`
318 vshr.u64 $temp,$temp,#16
324 vld1.32 {${Bi}[0]}, [$bptr,:32]!
325 veor $zero,$zero,$zero
327 vadd.u64 `&Dlo("$A0xB")`,`&Dlo("$A0xB")`,$temp
329 vmlal.u32 $A0xB,$Bi,${A0}[0]
330 vmlal.u32 $A1xB,$Bi,${A0}[1]
331 vmlal.u32 $A2xB,$Bi,${A1}[0]
332 vshl.i64 $temp,`&Dhi("$A0xB")`,#16
333 vmlal.u32 $A3xB,$Bi,${A1}[1]
335 vadd.u64 $temp,$temp,`&Dlo("$A0xB")`
336 veor $zero,$zero,$zero
337 subs $outer,$outer,#1
338 vmul.u32 $Ni,$temp,$M0
340 vmlal.u32 $A4xB,$Bi,${A2}[0]
341 vmlal.u32 $A5xB,$Bi,${A2}[1]
342 vmlal.u32 $A6xB,$Bi,${A3}[0]
344 vmlal.u32 $A7xB,$Bi,${A3}[1]
346 vmlal.u32 $A0xB,$Ni,${N0}[0]
347 vmlal.u32 $A1xB,$Ni,${N0}[1]
348 vmlal.u32 $A2xB,$Ni,${N1}[0]
349 vmlal.u32 $A3xB,$Ni,${N1}[1]
351 vmlal.u32 $A4xB,$Ni,${N2}[0]
353 vmlal.u32 $A5xB,$Ni,${N2}[1]
355 vmlal.u32 $A6xB,$Ni,${N3}[0]
357 vmlal.u32 $A7xB,$Ni,${N3}[1]
360 vshr.u64 $temp,$temp,#16
363 vadd.u64 $temp,$temp,`&Dhi("$Temp")`
366 vshr.u64 $temp,$temp,#16
370 vadd.u64 `&Dlo("$A0xB")`,`&Dlo("$A0xB")`,$temp
372 vshr.u64 $temp,`&Dlo("$A0xB")`,#16
374 vadd.u64 `&Dhi("$A0xB")`,`&Dhi("$A0xB")`,$temp
376 vshr.u64 $temp,`&Dhi("$A0xB")`,#16
377 vzip.16 `&Dlo("$A0xB")`,`&Dhi("$A0xB")`
383 vmlal.u32 $A0xB,$Ni,${N0}[0]
384 vld1.32 {$A0-$A3}, [$aptr]!
385 vmlal.u32 $A1xB,$Ni,${N0}[1]
386 subs $inner,$inner,#8
387 vmlal.u32 $A2xB,$Ni,${N1}[0]
388 vmlal.u32 $A3xB,$Ni,${N1}[1]
390 vmlal.u32 $A4xB,$Ni,${N2}[0]
391 vld1.32 {$N0-$N1}, [$nptr]!
392 vmlal.u32 $A5xB,$Ni,${N2}[1]
393 vst1.64 {$A0xB-$A1xB}, [$toutptr,:256]!
394 vmlal.u32 $A6xB,$Ni,${N3}[0]
395 vmlal.u32 $A7xB,$Ni,${N3}[1]
396 vst1.64 {$A2xB-$A3xB}, [$toutptr,:256]!
398 vmull.u32 $A0xB,$Bi,${A0}[0]
399 vld1.32 {$N2-$N3}, [$nptr]!
400 vmull.u32 $A1xB,$Bi,${A0}[1]
401 vst1.64 {$A4xB-$A5xB}, [$toutptr,:256]!
402 vmull.u32 $A2xB,$Bi,${A1}[0]
403 vmull.u32 $A3xB,$Bi,${A1}[1]
404 vst1.64 {$A6xB-$A7xB}, [$toutptr,:256]!
406 vmull.u32 $A4xB,$Bi,${A2}[0]
407 vmull.u32 $A5xB,$Bi,${A2}[1]
408 vmull.u32 $A6xB,$Bi,${A3}[0]
409 vmull.u32 $A7xB,$Bi,${A3}[1]
413 vmlal.u32 $A0xB,$Ni,${N0}[0]
415 vmlal.u32 $A1xB,$Ni,${N0}[1]
416 sub $aptr,$aptr,$num,lsl#2 @ rewind $aptr
417 vmlal.u32 $A2xB,$Ni,${N1}[0]
418 vld1.64 {$Temp}, [sp,:128]
419 vmlal.u32 $A3xB,$Ni,${N1}[1]
422 vmlal.u32 $A4xB,$Ni,${N2}[0]
423 vst1.64 {$A0xB-$A1xB}, [$toutptr,:256]!
424 vmlal.u32 $A5xB,$Ni,${N2}[1]
425 vshr.u64 $temp,$temp,#16
426 vld1.64 {$A0xB}, [$tinptr, :128]!
427 vmlal.u32 $A6xB,$Ni,${N3}[0]
428 vst1.64 {$A2xB-$A3xB}, [$toutptr,:256]!
429 vmlal.u32 $A7xB,$Ni,${N3}[1]
431 vst1.64 {$A4xB-$A5xB}, [$toutptr,:256]!
432 vadd.u64 $temp,$temp,`&Dhi("$Temp")`
434 vst1.64 {$A6xB-$A7xB}, [$toutptr,:256]!
435 vld1.64 {$A1xB-$A2xB}, [$tinptr, :256]!
436 vst1.64 {$Z}, [$toutptr,:128]
437 vshr.u64 $temp,$temp,#16
443 vld1.32 {${Bi}[0]}, [$bptr,:32]!
444 sub $nptr,$nptr,$num,lsl#2 @ rewind $nptr
445 vld1.32 {$A0-$A3}, [$aptr]!
446 veor $zero,$zero,$zero
450 vadd.u64 `&Dlo("$A0xB")`,`&Dlo("$A0xB")`,$temp
452 vmlal.u32 $A0xB,$Bi,${A0}[0]
453 vld1.64 {$A3xB-$A4xB},[$tinptr,:256]!
454 vmlal.u32 $A1xB,$Bi,${A0}[1]
455 vmlal.u32 $A2xB,$Bi,${A1}[0]
456 vld1.64 {$A5xB-$A6xB},[$tinptr,:256]!
457 vmlal.u32 $A3xB,$Bi,${A1}[1]
459 vshl.i64 $temp,`&Dhi("$A0xB")`,#16
460 veor $zero,$zero,$zero
461 vadd.u64 $temp,$temp,`&Dlo("$A0xB")`
462 vld1.64 {$A7xB},[$tinptr,:128]!
463 vmul.u32 $Ni,$temp,$M0
465 vmlal.u32 $A4xB,$Bi,${A2}[0]
466 vld1.32 {$N0-$N3}, [$nptr]!
467 vmlal.u32 $A5xB,$Bi,${A2}[1]
468 vmlal.u32 $A6xB,$Bi,${A3}[0]
470 vmlal.u32 $A7xB,$Bi,${A3}[1]
473 vmlal.u32 $A0xB,$Ni,${N0}[0]
474 vld1.32 {$A0-$A3}, [$aptr]!
475 vmlal.u32 $A1xB,$Ni,${N0}[1]
476 subs $inner,$inner,#8
477 vmlal.u32 $A2xB,$Ni,${N1}[0]
478 vmlal.u32 $A3xB,$Ni,${N1}[1]
479 vst1.64 {$A0xB-$A1xB}, [$toutptr,:256]!
481 vmlal.u32 $A4xB,$Ni,${N2}[0]
482 vld1.64 {$A0xB}, [$tinptr, :128]!
483 vmlal.u32 $A5xB,$Ni,${N2}[1]
484 vst1.64 {$A2xB-$A3xB}, [$toutptr,:256]!
485 vmlal.u32 $A6xB,$Ni,${N3}[0]
486 vld1.64 {$A1xB-$A2xB}, [$tinptr, :256]!
487 vmlal.u32 $A7xB,$Ni,${N3}[1]
488 vst1.64 {$A4xB-$A5xB}, [$toutptr,:256]!
490 vmlal.u32 $A0xB,$Bi,${A0}[0]
491 vld1.64 {$A3xB-$A4xB}, [$tinptr, :256]!
492 vmlal.u32 $A1xB,$Bi,${A0}[1]
493 vst1.64 {$A6xB-$A7xB}, [$toutptr,:256]!
494 vmlal.u32 $A2xB,$Bi,${A1}[0]
495 vld1.64 {$A5xB-$A6xB}, [$tinptr, :256]!
496 vmlal.u32 $A3xB,$Bi,${A1}[1]
497 vld1.32 {$N0-$N3}, [$nptr]!
499 vmlal.u32 $A4xB,$Bi,${A2}[0]
500 vld1.64 {$A7xB}, [$tinptr, :128]!
501 vmlal.u32 $A5xB,$Bi,${A2}[1]
502 vmlal.u32 $A6xB,$Bi,${A3}[0]
503 vmlal.u32 $A7xB,$Bi,${A3}[1]
507 vmlal.u32 $A0xB,$Ni,${N0}[0]
509 vmlal.u32 $A1xB,$Ni,${N0}[1]
510 sub $aptr,$aptr,$num,lsl#2 @ rewind $aptr
511 vmlal.u32 $A2xB,$Ni,${N1}[0]
512 vld1.64 {$Temp}, [sp,:128]
513 vmlal.u32 $A3xB,$Ni,${N1}[1]
514 subs $outer,$outer,#1
516 vmlal.u32 $A4xB,$Ni,${N2}[0]
517 vst1.64 {$A0xB-$A1xB}, [$toutptr,:256]!
518 vmlal.u32 $A5xB,$Ni,${N2}[1]
519 vld1.64 {$A0xB}, [$tinptr, :128]!
520 vshr.u64 $temp,$temp,#16
521 vst1.64 {$A2xB-$A3xB}, [$toutptr,:256]!
522 vmlal.u32 $A6xB,$Ni,${N3}[0]
523 vld1.64 {$A1xB-$A2xB}, [$tinptr, :256]!
524 vmlal.u32 $A7xB,$Ni,${N3}[1]
526 vst1.64 {$A4xB-$A5xB}, [$toutptr,:256]!
527 vadd.u64 $temp,$temp,`&Dhi("$Temp")`
528 vst1.64 {$A6xB-$A7xB}, [$toutptr,:256]!
529 vshr.u64 $temp,$temp,#16
537 vadd.u64 `&Dlo("$A0xB")`,`&Dlo("$A0xB")`,$temp
538 vld1.64 {$A3xB-$A4xB}, [$tinptr, :256]!
539 vshr.u64 $temp,`&Dlo("$A0xB")`,#16
540 vadd.u64 `&Dhi("$A0xB")`,`&Dhi("$A0xB")`,$temp
541 vld1.64 {$A5xB-$A6xB}, [$tinptr, :256]!
542 vshr.u64 $temp,`&Dhi("$A0xB")`,#16
543 vld1.64 {$A7xB}, [$tinptr, :128]!
544 vzip.16 `&Dlo("$A0xB")`,`&Dhi("$A0xB")`
547 vadd.u64 `&Dlo("$A1xB")`,`&Dlo("$A1xB")`,$temp
548 vst1.32 {`&Dlo("$A0xB")`[0]}, [$toutptr, :32]!
549 vshr.u64 $temp,`&Dlo("$A1xB")`,#16
550 vadd.u64 `&Dhi("$A1xB")`,`&Dhi("$A1xB")`,$temp
551 vshr.u64 $temp,`&Dhi("$A1xB")`,#16
552 vzip.16 `&Dlo("$A1xB")`,`&Dhi("$A1xB")`
554 vadd.u64 `&Dlo("$A2xB")`,`&Dlo("$A2xB")`,$temp
555 vst1.32 {`&Dlo("$A1xB")`[0]}, [$toutptr, :32]!
556 vshr.u64 $temp,`&Dlo("$A2xB")`,#16
557 vadd.u64 `&Dhi("$A2xB")`,`&Dhi("$A2xB")`,$temp
558 vshr.u64 $temp,`&Dhi("$A2xB")`,#16
559 vzip.16 `&Dlo("$A2xB")`,`&Dhi("$A2xB")`
561 vadd.u64 `&Dlo("$A3xB")`,`&Dlo("$A3xB")`,$temp
562 vst1.32 {`&Dlo("$A2xB")`[0]}, [$toutptr, :32]!
563 vshr.u64 $temp,`&Dlo("$A3xB")`,#16
564 vadd.u64 `&Dhi("$A3xB")`,`&Dhi("$A3xB")`,$temp
565 vshr.u64 $temp,`&Dhi("$A3xB")`,#16
566 vzip.16 `&Dlo("$A3xB")`,`&Dhi("$A3xB")`
568 vadd.u64 `&Dlo("$A4xB")`,`&Dlo("$A4xB")`,$temp
569 vst1.32 {`&Dlo("$A3xB")`[0]}, [$toutptr, :32]!
570 vshr.u64 $temp,`&Dlo("$A4xB")`,#16
571 vadd.u64 `&Dhi("$A4xB")`,`&Dhi("$A4xB")`,$temp
572 vshr.u64 $temp,`&Dhi("$A4xB")`,#16
573 vzip.16 `&Dlo("$A4xB")`,`&Dhi("$A4xB")`
575 vadd.u64 `&Dlo("$A5xB")`,`&Dlo("$A5xB")`,$temp
576 vst1.32 {`&Dlo("$A4xB")`[0]}, [$toutptr, :32]!
577 vshr.u64 $temp,`&Dlo("$A5xB")`,#16
578 vadd.u64 `&Dhi("$A5xB")`,`&Dhi("$A5xB")`,$temp
579 vshr.u64 $temp,`&Dhi("$A5xB")`,#16
580 vzip.16 `&Dlo("$A5xB")`,`&Dhi("$A5xB")`
582 vadd.u64 `&Dlo("$A6xB")`,`&Dlo("$A6xB")`,$temp
583 vst1.32 {`&Dlo("$A5xB")`[0]}, [$toutptr, :32]!
584 vshr.u64 $temp,`&Dlo("$A6xB")`,#16
585 vadd.u64 `&Dhi("$A6xB")`,`&Dhi("$A6xB")`,$temp
586 vld1.64 {$A0xB}, [$tinptr, :128]!
587 vshr.u64 $temp,`&Dhi("$A6xB")`,#16
588 vzip.16 `&Dlo("$A6xB")`,`&Dhi("$A6xB")`
590 vadd.u64 `&Dlo("$A7xB")`,`&Dlo("$A7xB")`,$temp
591 vst1.32 {`&Dlo("$A6xB")`[0]}, [$toutptr, :32]!
592 vshr.u64 $temp,`&Dlo("$A7xB")`,#16
593 vadd.u64 `&Dhi("$A7xB")`,`&Dhi("$A7xB")`,$temp
594 vld1.64 {$A1xB-$A2xB}, [$tinptr, :256]!
595 vshr.u64 $temp,`&Dhi("$A7xB")`,#16
596 vzip.16 `&Dlo("$A7xB")`,`&Dhi("$A7xB")`
597 subs $inner,$inner,#8
598 vst1.32 {`&Dlo("$A7xB")`[0]}, [$toutptr, :32]!
602 vst1.32 {${temp}[0]}, [$toutptr, :32] @ top-most bit
603 sub $nptr,$nptr,$num,lsl#2 @ rewind $nptr
604 subs $aptr,sp,#0 @ clear carry flag
605 add $bptr,sp,$num,lsl#2
608 ldmia $aptr!, {r4-r7}
609 ldmia $nptr!, {r8-r11}
614 teq $aptr,$bptr @ preserves carry
615 stmia $rptr!, {r8-r11}
618 ldr r10, [$aptr] @ load top-most bit
620 sub r11,$bptr,sp @ this is num*4
623 sub $rptr,$rptr,r11 @ rewind $rptr
624 mov $nptr,$bptr @ second 3/4th of frame
625 sbcs r10,r10,#0 @ result is carry flag
628 ldmia $aptr!, {r4-r7}
629 ldmia $rptr, {r8-r11}
631 vst1.64 {q0-q1}, [$nptr,:256]! @ wipe
634 vst1.64 {q0-q1}, [$nptr,:256]! @ wipe
637 stmia $rptr!, {r8-r11}
639 ldmia $rptr, {r8-r11}
641 vst1.64 {q0-q1}, [$aptr,:256]! @ wipe
644 vst1.64 {q0-q1}, [$nptr,:256]! @ wipe
646 teq $aptr,$bptr @ preserves carry
647 stmia $rptr!, {r8-r11}
648 bne .LNEON_copy_n_zap
654 .size bn_mul8x_mont_neon,.-bn_mul8x_mont_neon
659 .asciz "Montgomery multiplication for ARMv4/NEON, CRYPTOGAMS by <appro\@openssl.org>"
662 .comm OPENSSL_armcap_P,4,4
666 $code =~ s/\`([^\`]*)\`/eval $1/gem;
667 $code =~ s/\bbx\s+lr\b/.word\t0xe12fff1e/gm; # make it possible to compile with -march=armv4