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      1 #!/usr/bin/env perl
      2 #
      3 # ====================================================================
      4 # Written by Andy Polyakov <appro (at] 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 # ====================================================================
      9 #
     10 # July 2004
     11 #
     12 # 2.22x RC4 tune-up:-) It should be noted though that my hand [as in
     13 # "hand-coded assembler"] doesn't stand for the whole improvement
     14 # coefficient. It turned out that eliminating RC4_CHAR from config
     15 # line results in ~40% improvement (yes, even for C implementation).
     16 # Presumably it has everything to do with AMD cache architecture and
     17 # RAW or whatever penalties. Once again! The module *requires* config
     18 # line *without* RC4_CHAR! As for coding "secret," I bet on partial
     19 # register arithmetics. For example instead of 'inc %r8; and $255,%r8'
     20 # I simply 'inc %r8b'. Even though optimization manual discourages
     21 # to operate on partial registers, it turned out to be the best bet.
     22 # At least for AMD... How IA32E would perform remains to be seen...
     23 
     24 # November 2004
     25 #
     26 # As was shown by Marc Bevand reordering of couple of load operations
     27 # results in even higher performance gain of 3.3x:-) At least on
     28 # Opteron... For reference, 1x in this case is RC4_CHAR C-code
     29 # compiled with gcc 3.3.2, which performs at ~54MBps per 1GHz clock.
     30 # Latter means that if you want to *estimate* what to expect from
     31 # *your* Opteron, then multiply 54 by 3.3 and clock frequency in GHz.
     32 
     33 # November 2004
     34 #
     35 # Intel P4 EM64T core was found to run the AMD64 code really slow...
     36 # The only way to achieve comparable performance on P4 was to keep
     37 # RC4_CHAR. Kind of ironic, huh? As it's apparently impossible to
     38 # compose blended code, which would perform even within 30% marginal
     39 # on either AMD and Intel platforms, I implement both cases. See
     40 # rc4_skey.c for further details...
     41 
     42 # April 2005
     43 #
     44 # P4 EM64T core appears to be "allergic" to 64-bit inc/dec. Replacing 
     45 # those with add/sub results in 50% performance improvement of folded
     46 # loop...
     47 
     48 # May 2005
     49 #
     50 # As was shown by Zou Nanhai loop unrolling can improve Intel EM64T
     51 # performance by >30% [unlike P4 32-bit case that is]. But this is
     52 # provided that loads are reordered even more aggressively! Both code
     53 # pathes, AMD64 and EM64T, reorder loads in essentially same manner
     54 # as my IA-64 implementation. On Opteron this resulted in modest 5%
     55 # improvement [I had to test it], while final Intel P4 performance
     56 # achieves respectful 432MBps on 2.8GHz processor now. For reference.
     57 # If executed on Xeon, current RC4_CHAR code-path is 2.7x faster than
     58 # RC4_INT code-path. While if executed on Opteron, it's only 25%
     59 # slower than the RC4_INT one [meaning that if CPU -arch detection
     60 # is not implemented, then this final RC4_CHAR code-path should be
     61 # preferred, as it provides better *all-round* performance].
     62 
     63 # March 2007
     64 #
     65 # Intel Core2 was observed to perform poorly on both code paths:-( It
     66 # apparently suffers from some kind of partial register stall, which
     67 # occurs in 64-bit mode only [as virtually identical 32-bit loop was
     68 # observed to outperform 64-bit one by almost 50%]. Adding two movzb to
     69 # cloop1 boosts its performance by 80%! This loop appears to be optimal
     70 # fit for Core2 and therefore the code was modified to skip cloop8 on
     71 # this CPU.
     72 
     73 # May 2010
     74 #
     75 # Intel Westmere was observed to perform suboptimally. Adding yet
     76 # another movzb to cloop1 improved performance by almost 50%! Core2
     77 # performance is improved too, but nominally...
     78 
     79 # May 2011
     80 #
     81 # The only code path that was not modified is P4-specific one. Non-P4
     82 # Intel code path optimization is heavily based on submission by Maxim
     83 # Perminov, Maxim Locktyukhin and Jim Guilford of Intel. I've used
     84 # some of the ideas even in attempt to optmize the original RC4_INT
     85 # code path... Current performance in cycles per processed byte (less
     86 # is better) and improvement coefficients relative to previous
     87 # version of this module are:
     88 #
     89 # Opteron	5.3/+0%(*)
     90 # P4		6.5
     91 # Core2		6.2/+15%(**)
     92 # Westmere	4.2/+60%
     93 # Sandy Bridge	4.2/+120%
     94 # Atom		9.3/+80%
     95 #
     96 # (*)	But corresponding loop has less instructions, which should have
     97 #	positive effect on upcoming Bulldozer, which has one less ALU.
     98 #	For reference, Intel code runs at 6.8 cpb rate on Opteron.
     99 # (**)	Note that Core2 result is ~15% lower than corresponding result
    100 #	for 32-bit code, meaning that it's possible to improve it,
    101 #	but more than likely at the cost of the others (see rc4-586.pl
    102 #	to get the idea)...
    103 
    104 $flavour = shift;
    105 $output  = shift;
    106 if ($flavour =~ /\./) { $output = $flavour; undef $flavour; }
    107 
    108 $win64=0; $win64=1 if ($flavour =~ /[nm]asm|mingw64/ || $output =~ /\.asm$/);
    109 
    110 $0 =~ m/(.*[\/\\])[^\/\\]+$/; $dir=$1;
    111 ( $xlate="${dir}x86_64-xlate.pl" and -f $xlate ) or
    112 ( $xlate="${dir}../../perlasm/x86_64-xlate.pl" and -f $xlate) or
    113 die "can't locate x86_64-xlate.pl";
    114 
    115 open OUT,"| \"$^X\" $xlate $flavour $output";
    116 *STDOUT=*OUT;
    117 
    118 $dat="%rdi";	    # arg1
    119 $len="%rsi";	    # arg2
    120 $inp="%rdx";	    # arg3
    121 $out="%rcx";	    # arg4
    122 
    123 {
    124 $code=<<___;
    125 .text
    126 .extern	OPENSSL_ia32cap_P
    127 
    128 .globl	asm_RC4
    129 .type	asm_RC4,\@function,4
    130 .align	16
    131 asm_RC4:
    132 	or	$len,$len
    133 	jne	.Lentry
    134 	ret
    135 .Lentry:
    136 	push	%rbx
    137 	push	%r12
    138 	push	%r13
    139 .Lprologue:
    140 	mov	$len,%r11
    141 	mov	$inp,%r12
    142 	mov	$out,%r13
    143 ___
    144 my $len="%r11";		# reassign input arguments
    145 my $inp="%r12";
    146 my $out="%r13";
    147 
    148 my @XX=("%r10","%rsi");
    149 my @TX=("%rax","%rbx");
    150 my $YY="%rcx";
    151 my $TY="%rdx";
    152 
    153 $code.=<<___;
    154 	xor	$XX[0],$XX[0]
    155 	xor	$YY,$YY
    156 
    157 	lea	8($dat),$dat
    158 	mov	-8($dat),$XX[0]#b
    159 	mov	-4($dat),$YY#b
    160 	cmpl	\$-1,256($dat)
    161 	je	.LRC4_CHAR
    162 	mov	OPENSSL_ia32cap_P(%rip),%r8d
    163 	xor	$TX[1],$TX[1]
    164 	inc	$XX[0]#b
    165 	sub	$XX[0],$TX[1]
    166 	sub	$inp,$out
    167 	movl	($dat,$XX[0],4),$TX[0]#d
    168 	test	\$-16,$len
    169 	jz	.Lloop1
    170 	bt	\$30,%r8d	# Intel CPU?
    171 	jc	.Lintel
    172 	and	\$7,$TX[1]
    173 	lea	1($XX[0]),$XX[1]
    174 	jz	.Loop8
    175 	sub	$TX[1],$len
    176 .Loop8_warmup:
    177 	add	$TX[0]#b,$YY#b
    178 	movl	($dat,$YY,4),$TY#d
    179 	movl	$TX[0]#d,($dat,$YY,4)
    180 	movl	$TY#d,($dat,$XX[0],4)
    181 	add	$TY#b,$TX[0]#b
    182 	inc	$XX[0]#b
    183 	movl	($dat,$TX[0],4),$TY#d
    184 	movl	($dat,$XX[0],4),$TX[0]#d
    185 	xorb	($inp),$TY#b
    186 	movb	$TY#b,($out,$inp)
    187 	lea	1($inp),$inp
    188 	dec	$TX[1]
    189 	jnz	.Loop8_warmup
    190 
    191 	lea	1($XX[0]),$XX[1]
    192 	jmp	.Loop8
    193 .align	16
    194 .Loop8:
    195 ___
    196 for ($i=0;$i<8;$i++) {
    197 $code.=<<___ if ($i==7);
    198 	add	\$8,$XX[1]#b
    199 ___
    200 $code.=<<___;
    201 	add	$TX[0]#b,$YY#b
    202 	movl	($dat,$YY,4),$TY#d
    203 	movl	$TX[0]#d,($dat,$YY,4)
    204 	movl	`4*($i==7?-1:$i)`($dat,$XX[1],4),$TX[1]#d
    205 	ror	\$8,%r8				# ror is redundant when $i=0
    206 	movl	$TY#d,4*$i($dat,$XX[0],4)
    207 	add	$TX[0]#b,$TY#b
    208 	movb	($dat,$TY,4),%r8b
    209 ___
    210 push(@TX,shift(@TX)); #push(@XX,shift(@XX));	# "rotate" registers
    211 }
    212 $code.=<<___;
    213 	add	\$8,$XX[0]#b
    214 	ror	\$8,%r8
    215 	sub	\$8,$len
    216 
    217 	xor	($inp),%r8
    218 	mov	%r8,($out,$inp)
    219 	lea	8($inp),$inp
    220 
    221 	test	\$-8,$len
    222 	jnz	.Loop8
    223 	cmp	\$0,$len
    224 	jne	.Lloop1
    225 	jmp	.Lexit
    226 
    227 .align	16
    228 .Lintel:
    229 	test	\$-32,$len
    230 	jz	.Lloop1
    231 	and	\$15,$TX[1]
    232 	jz	.Loop16_is_hot
    233 	sub	$TX[1],$len
    234 .Loop16_warmup:
    235 	add	$TX[0]#b,$YY#b
    236 	movl	($dat,$YY,4),$TY#d
    237 	movl	$TX[0]#d,($dat,$YY,4)
    238 	movl	$TY#d,($dat,$XX[0],4)
    239 	add	$TY#b,$TX[0]#b
    240 	inc	$XX[0]#b
    241 	movl	($dat,$TX[0],4),$TY#d
    242 	movl	($dat,$XX[0],4),$TX[0]#d
    243 	xorb	($inp),$TY#b
    244 	movb	$TY#b,($out,$inp)
    245 	lea	1($inp),$inp
    246 	dec	$TX[1]
    247 	jnz	.Loop16_warmup
    248 
    249 	mov	$YY,$TX[1]
    250 	xor	$YY,$YY
    251 	mov	$TX[1]#b,$YY#b
    252 
    253 .Loop16_is_hot:
    254 	lea	($dat,$XX[0],4),$XX[1]
    255 ___
    256 sub RC4_loop {
    257   my $i=shift;
    258   my $j=$i<0?0:$i;
    259   my $xmm="%xmm".($j&1);
    260 
    261     $code.="	add	\$16,$XX[0]#b\n"		if ($i==15);
    262     $code.="	movdqu	($inp),%xmm2\n"			if ($i==15);
    263     $code.="	add	$TX[0]#b,$YY#b\n"		if ($i<=0);
    264     $code.="	movl	($dat,$YY,4),$TY#d\n";
    265     $code.="	pxor	%xmm0,%xmm2\n"			if ($i==0);
    266     $code.="	psllq	\$8,%xmm1\n"			if ($i==0);
    267     $code.="	pxor	$xmm,$xmm\n"			if ($i<=1);
    268     $code.="	movl	$TX[0]#d,($dat,$YY,4)\n";
    269     $code.="	add	$TY#b,$TX[0]#b\n";
    270     $code.="	movl	`4*($j+1)`($XX[1]),$TX[1]#d\n"	if ($i<15);
    271     $code.="	movz	$TX[0]#b,$TX[0]#d\n";
    272     $code.="	movl	$TY#d,4*$j($XX[1])\n";
    273     $code.="	pxor	%xmm1,%xmm2\n"			if ($i==0);
    274     $code.="	lea	($dat,$XX[0],4),$XX[1]\n"	if ($i==15);
    275     $code.="	add	$TX[1]#b,$YY#b\n"		if ($i<15);
    276     $code.="	pinsrw	\$`($j>>1)&7`,($dat,$TX[0],4),$xmm\n";
    277     $code.="	movdqu	%xmm2,($out,$inp)\n"		if ($i==0);
    278     $code.="	lea	16($inp),$inp\n"		if ($i==0);
    279     $code.="	movl	($XX[1]),$TX[1]#d\n"		if ($i==15);
    280 }
    281 	RC4_loop(-1);
    282 $code.=<<___;
    283 	jmp	.Loop16_enter
    284 .align	16
    285 .Loop16:
    286 ___
    287 
    288 for ($i=0;$i<16;$i++) {
    289     $code.=".Loop16_enter:\n"		if ($i==1);
    290 	RC4_loop($i);
    291 	push(@TX,shift(@TX)); 		# "rotate" registers
    292 }
    293 $code.=<<___;
    294 	mov	$YY,$TX[1]
    295 	xor	$YY,$YY			# keyword to partial register
    296 	sub	\$16,$len
    297 	mov	$TX[1]#b,$YY#b
    298 	test	\$-16,$len
    299 	jnz	.Loop16
    300 
    301 	psllq	\$8,%xmm1
    302 	pxor	%xmm0,%xmm2
    303 	pxor	%xmm1,%xmm2
    304 	movdqu	%xmm2,($out,$inp)
    305 	lea	16($inp),$inp
    306 
    307 	cmp	\$0,$len
    308 	jne	.Lloop1
    309 	jmp	.Lexit
    310 
    311 .align	16
    312 .Lloop1:
    313 	add	$TX[0]#b,$YY#b
    314 	movl	($dat,$YY,4),$TY#d
    315 	movl	$TX[0]#d,($dat,$YY,4)
    316 	movl	$TY#d,($dat,$XX[0],4)
    317 	add	$TY#b,$TX[0]#b
    318 	inc	$XX[0]#b
    319 	movl	($dat,$TX[0],4),$TY#d
    320 	movl	($dat,$XX[0],4),$TX[0]#d
    321 	xorb	($inp),$TY#b
    322 	movb	$TY#b,($out,$inp)
    323 	lea	1($inp),$inp
    324 	dec	$len
    325 	jnz	.Lloop1
    326 	jmp	.Lexit
    327 
    328 .align	16
    329 .LRC4_CHAR:
    330 	add	\$1,$XX[0]#b
    331 	movzb	($dat,$XX[0]),$TX[0]#d
    332 	test	\$-8,$len
    333 	jz	.Lcloop1
    334 	jmp	.Lcloop8
    335 .align	16
    336 .Lcloop8:
    337 	mov	($inp),%r8d
    338 	mov	4($inp),%r9d
    339 ___
    340 # unroll 2x4-wise, because 64-bit rotates kill Intel P4...
    341 for ($i=0;$i<4;$i++) {
    342 $code.=<<___;
    343 	add	$TX[0]#b,$YY#b
    344 	lea	1($XX[0]),$XX[1]
    345 	movzb	($dat,$YY),$TY#d
    346 	movzb	$XX[1]#b,$XX[1]#d
    347 	movzb	($dat,$XX[1]),$TX[1]#d
    348 	movb	$TX[0]#b,($dat,$YY)
    349 	cmp	$XX[1],$YY
    350 	movb	$TY#b,($dat,$XX[0])
    351 	jne	.Lcmov$i			# Intel cmov is sloooow...
    352 	mov	$TX[0],$TX[1]
    353 .Lcmov$i:
    354 	add	$TX[0]#b,$TY#b
    355 	xor	($dat,$TY),%r8b
    356 	ror	\$8,%r8d
    357 ___
    358 push(@TX,shift(@TX)); push(@XX,shift(@XX));	# "rotate" registers
    359 }
    360 for ($i=4;$i<8;$i++) {
    361 $code.=<<___;
    362 	add	$TX[0]#b,$YY#b
    363 	lea	1($XX[0]),$XX[1]
    364 	movzb	($dat,$YY),$TY#d
    365 	movzb	$XX[1]#b,$XX[1]#d
    366 	movzb	($dat,$XX[1]),$TX[1]#d
    367 	movb	$TX[0]#b,($dat,$YY)
    368 	cmp	$XX[1],$YY
    369 	movb	$TY#b,($dat,$XX[0])
    370 	jne	.Lcmov$i			# Intel cmov is sloooow...
    371 	mov	$TX[0],$TX[1]
    372 .Lcmov$i:
    373 	add	$TX[0]#b,$TY#b
    374 	xor	($dat,$TY),%r9b
    375 	ror	\$8,%r9d
    376 ___
    377 push(@TX,shift(@TX)); push(@XX,shift(@XX));	# "rotate" registers
    378 }
    379 $code.=<<___;
    380 	lea	-8($len),$len
    381 	mov	%r8d,($out)
    382 	lea	8($inp),$inp
    383 	mov	%r9d,4($out)
    384 	lea	8($out),$out
    385 
    386 	test	\$-8,$len
    387 	jnz	.Lcloop8
    388 	cmp	\$0,$len
    389 	jne	.Lcloop1
    390 	jmp	.Lexit
    391 ___
    392 $code.=<<___;
    393 .align	16
    394 .Lcloop1:
    395 	add	$TX[0]#b,$YY#b
    396 	movzb	$YY#b,$YY#d
    397 	movzb	($dat,$YY),$TY#d
    398 	movb	$TX[0]#b,($dat,$YY)
    399 	movb	$TY#b,($dat,$XX[0])
    400 	add	$TX[0]#b,$TY#b
    401 	add	\$1,$XX[0]#b
    402 	movzb	$TY#b,$TY#d
    403 	movzb	$XX[0]#b,$XX[0]#d
    404 	movzb	($dat,$TY),$TY#d
    405 	movzb	($dat,$XX[0]),$TX[0]#d
    406 	xorb	($inp),$TY#b
    407 	lea	1($inp),$inp
    408 	movb	$TY#b,($out)
    409 	lea	1($out),$out
    410 	sub	\$1,$len
    411 	jnz	.Lcloop1
    412 	jmp	.Lexit
    413 
    414 .align	16
    415 .Lexit:
    416 	sub	\$1,$XX[0]#b
    417 	movl	$XX[0]#d,-8($dat)
    418 	movl	$YY#d,-4($dat)
    419 
    420 	mov	(%rsp),%r13
    421 	mov	8(%rsp),%r12
    422 	mov	16(%rsp),%rbx
    423 	add	\$24,%rsp
    424 .Lepilogue:
    425 	ret
    426 .size	asm_RC4,.-asm_RC4
    427 ___
    428 }
    429 
    430 $idx="%r8";
    431 $ido="%r9";
    432 
    433 $code.=<<___;
    434 .globl	asm_RC4_set_key
    435 .type	asm_RC4_set_key,\@function,3
    436 .align	16
    437 asm_RC4_set_key:
    438 	lea	8($dat),$dat
    439 	lea	($inp,$len),$inp
    440 	neg	$len
    441 	mov	$len,%rcx
    442 	xor	%eax,%eax
    443 	xor	$ido,$ido
    444 	xor	%r10,%r10
    445 	xor	%r11,%r11
    446 
    447 	mov	OPENSSL_ia32cap_P(%rip),$idx#d
    448 	bt	\$20,$idx#d	# RC4_CHAR?
    449 	jc	.Lc1stloop
    450 	jmp	.Lw1stloop
    451 
    452 .align	16
    453 .Lw1stloop:
    454 	mov	%eax,($dat,%rax,4)
    455 	add	\$1,%al
    456 	jnc	.Lw1stloop
    457 
    458 	xor	$ido,$ido
    459 	xor	$idx,$idx
    460 .align	16
    461 .Lw2ndloop:
    462 	mov	($dat,$ido,4),%r10d
    463 	add	($inp,$len,1),$idx#b
    464 	add	%r10b,$idx#b
    465 	add	\$1,$len
    466 	mov	($dat,$idx,4),%r11d
    467 	cmovz	%rcx,$len
    468 	mov	%r10d,($dat,$idx,4)
    469 	mov	%r11d,($dat,$ido,4)
    470 	add	\$1,$ido#b
    471 	jnc	.Lw2ndloop
    472 	jmp	.Lexit_key
    473 
    474 .align	16
    475 .Lc1stloop:
    476 	mov	%al,($dat,%rax)
    477 	add	\$1,%al
    478 	jnc	.Lc1stloop
    479 
    480 	xor	$ido,$ido
    481 	xor	$idx,$idx
    482 .align	16
    483 .Lc2ndloop:
    484 	mov	($dat,$ido),%r10b
    485 	add	($inp,$len),$idx#b
    486 	add	%r10b,$idx#b
    487 	add	\$1,$len
    488 	mov	($dat,$idx),%r11b
    489 	jnz	.Lcnowrap
    490 	mov	%rcx,$len
    491 .Lcnowrap:
    492 	mov	%r10b,($dat,$idx)
    493 	mov	%r11b,($dat,$ido)
    494 	add	\$1,$ido#b
    495 	jnc	.Lc2ndloop
    496 	movl	\$-1,256($dat)
    497 
    498 .align	16
    499 .Lexit_key:
    500 	xor	%eax,%eax
    501 	mov	%eax,-8($dat)
    502 	mov	%eax,-4($dat)
    503 	ret
    504 .size	asm_RC4_set_key,.-asm_RC4_set_key
    505 ___
    506 
    507 # EXCEPTION_DISPOSITION handler (EXCEPTION_RECORD *rec,ULONG64 frame,
    508 #		CONTEXT *context,DISPATCHER_CONTEXT *disp)
    509 if ($win64) {
    510 $rec="%rcx";
    511 $frame="%rdx";
    512 $context="%r8";
    513 $disp="%r9";
    514 
    515 $code.=<<___;
    516 .extern	__imp_RtlVirtualUnwind
    517 .type	stream_se_handler,\@abi-omnipotent
    518 .align	16
    519 stream_se_handler:
    520 	push	%rsi
    521 	push	%rdi
    522 	push	%rbx
    523 	push	%rbp
    524 	push	%r12
    525 	push	%r13
    526 	push	%r14
    527 	push	%r15
    528 	pushfq
    529 	sub	\$64,%rsp
    530 
    531 	mov	120($context),%rax	# pull context->Rax
    532 	mov	248($context),%rbx	# pull context->Rip
    533 
    534 	lea	.Lprologue(%rip),%r10
    535 	cmp	%r10,%rbx		# context->Rip<prologue label
    536 	jb	.Lin_prologue
    537 
    538 	mov	152($context),%rax	# pull context->Rsp
    539 
    540 	lea	.Lepilogue(%rip),%r10
    541 	cmp	%r10,%rbx		# context->Rip>=epilogue label
    542 	jae	.Lin_prologue
    543 
    544 	lea	24(%rax),%rax
    545 
    546 	mov	-8(%rax),%rbx
    547 	mov	-16(%rax),%r12
    548 	mov	-24(%rax),%r13
    549 	mov	%rbx,144($context)	# restore context->Rbx
    550 	mov	%r12,216($context)	# restore context->R12
    551 	mov	%r13,224($context)	# restore context->R13
    552 
    553 .Lin_prologue:
    554 	mov	8(%rax),%rdi
    555 	mov	16(%rax),%rsi
    556 	mov	%rax,152($context)	# restore context->Rsp
    557 	mov	%rsi,168($context)	# restore context->Rsi
    558 	mov	%rdi,176($context)	# restore context->Rdi
    559 
    560 	jmp	.Lcommon_seh_exit
    561 .size	stream_se_handler,.-stream_se_handler
    562 
    563 .type	key_se_handler,\@abi-omnipotent
    564 .align	16
    565 key_se_handler:
    566 	push	%rsi
    567 	push	%rdi
    568 	push	%rbx
    569 	push	%rbp
    570 	push	%r12
    571 	push	%r13
    572 	push	%r14
    573 	push	%r15
    574 	pushfq
    575 	sub	\$64,%rsp
    576 
    577 	mov	152($context),%rax	# pull context->Rsp
    578 	mov	8(%rax),%rdi
    579 	mov	16(%rax),%rsi
    580 	mov	%rsi,168($context)	# restore context->Rsi
    581 	mov	%rdi,176($context)	# restore context->Rdi
    582 
    583 .Lcommon_seh_exit:
    584 
    585 	mov	40($disp),%rdi		# disp->ContextRecord
    586 	mov	$context,%rsi		# context
    587 	mov	\$154,%ecx		# sizeof(CONTEXT)
    588 	.long	0xa548f3fc		# cld; rep movsq
    589 
    590 	mov	$disp,%rsi
    591 	xor	%rcx,%rcx		# arg1, UNW_FLAG_NHANDLER
    592 	mov	8(%rsi),%rdx		# arg2, disp->ImageBase
    593 	mov	0(%rsi),%r8		# arg3, disp->ControlPc
    594 	mov	16(%rsi),%r9		# arg4, disp->FunctionEntry
    595 	mov	40(%rsi),%r10		# disp->ContextRecord
    596 	lea	56(%rsi),%r11		# &disp->HandlerData
    597 	lea	24(%rsi),%r12		# &disp->EstablisherFrame
    598 	mov	%r10,32(%rsp)		# arg5
    599 	mov	%r11,40(%rsp)		# arg6
    600 	mov	%r12,48(%rsp)		# arg7
    601 	mov	%rcx,56(%rsp)		# arg8, (NULL)
    602 	call	*__imp_RtlVirtualUnwind(%rip)
    603 
    604 	mov	\$1,%eax		# ExceptionContinueSearch
    605 	add	\$64,%rsp
    606 	popfq
    607 	pop	%r15
    608 	pop	%r14
    609 	pop	%r13
    610 	pop	%r12
    611 	pop	%rbp
    612 	pop	%rbx
    613 	pop	%rdi
    614 	pop	%rsi
    615 	ret
    616 .size	key_se_handler,.-key_se_handler
    617 
    618 .section	.pdata
    619 .align	4
    620 	.rva	.LSEH_begin_asm_RC4
    621 	.rva	.LSEH_end_asm_RC4
    622 	.rva	.LSEH_info_asm_RC4
    623 
    624 	.rva	.LSEH_begin_asm_RC4_set_key
    625 	.rva	.LSEH_end_asm_RC4_set_key
    626 	.rva	.LSEH_info_asm_RC4_set_key
    627 
    628 .section	.xdata
    629 .align	8
    630 .LSEH_info_asm_RC4:
    631 	.byte	9,0,0,0
    632 	.rva	stream_se_handler
    633 .LSEH_info_asm_RC4_set_key:
    634 	.byte	9,0,0,0
    635 	.rva	key_se_handler
    636 ___
    637 }
    638 
    639 sub reg_part {
    640 my ($reg,$conv)=@_;
    641     if ($reg =~ /%r[0-9]+/)	{ $reg .= $conv; }
    642     elsif ($conv eq "b")	{ $reg =~ s/%[er]([^x]+)x?/%$1l/;	}
    643     elsif ($conv eq "w")	{ $reg =~ s/%[er](.+)/%$1/;		}
    644     elsif ($conv eq "d")	{ $reg =~ s/%[er](.+)/%e$1/;		}
    645     return $reg;
    646 }
    647 
    648 $code =~ s/(%[a-z0-9]+)#([bwd])/reg_part($1,$2)/gem;
    649 $code =~ s/\`([^\`]*)\`/eval $1/gem;
    650 
    651 print $code;
    652 
    653 close STDOUT;
    654