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/crypto/openssl/crypto/perlasm/x86_64-xlate.pl

https://bitbucket.org/freebsd/freebsd-head/
Perl | 1080 lines | 734 code | 56 blank | 290 comment | 178 complexity | 8cb1ff5a02a6dd2fbcaad9402096c880 MD5 | raw file
Possible License(s): MPL-2.0-no-copyleft-exception, BSD-3-Clause, LGPL-2.0, LGPL-2.1, BSD-2-Clause, 0BSD, JSON, AGPL-1.0, GPL-2.0 
    

  1. #!/usr/bin/env perl
    2. 

  2. 

  3. # Ascetic x86_64 AT&T to MASM/NASM assembler translator by <appro>.
    4. 

  4. #
    5. 

  5. # Why AT&T to MASM and not vice versa? Several reasons. Because AT&T
    6. 

  6. # format is way easier to parse. Because it's simpler to "gear" from
    7. 

  7. # Unix ABI to Windows one [see cross-reference "card" at the end of
    8. 

  8. # file]. Because Linux targets were available first...
    9. 

  9. #
    10. 

  10. # In addition the script also "distills" code suitable for GNU
    11. 

  11. # assembler, so that it can be compiled with more rigid assemblers,
    12. 

  12. # such as Solaris /usr/ccs/bin/as.
    13. 

  13. #
    14. 

  14. # This translator is not designed to convert *arbitrary* assembler
    15. 

  15. # code from AT&T format to MASM one. It's designed to convert just
    16. 

  16. # enough to provide for dual-ABI OpenSSL modules development...
    17. 

  17. # There *are* limitations and you might have to modify your assembler
    18. 

  18. # code or this script to achieve the desired result...
    19. 

  19. #
    20. 

  20. # Currently recognized limitations:
    21. 

  21. #
    22. 

  22. # - can't use multiple ops per line;
    23. 

  23. #
    24. 

  24. # Dual-ABI styling rules.
    25. 

  25. #
    26. 

  26. # 1. Adhere to Unix register and stack layout [see cross-reference
    27. 

  27. #    ABI "card" at the end for explanation].
    28. 

  28. # 2. Forget about "red zone," stick to more traditional blended
    29. 

  29. #    stack frame allocation. If volatile storage is actually required
    30. 

  30. #    that is. If not, just leave the stack as is.
    31. 

  31. # 3. Functions tagged with ".type name,@function" get crafted with
    32. 

  32. #    unified Win64 prologue and epilogue automatically. If you want
    33. 

  33. #    to take care of ABI differences yourself, tag functions as
    34. 

  34. #    ".type name,@abi-omnipotent" instead.
    35. 

  35. # 4. To optimize the Win64 prologue you can specify number of input
    36. 

  36. #    arguments as ".type name,@function,N." Keep in mind that if N is
    37. 

  37. #    larger than 6, then you *have to* write "abi-omnipotent" code,
    38. 

  38. #    because >6 cases can't be addressed with unified prologue.
    39. 

  39. # 5. Name local labels as .L*, do *not* use dynamic labels such as 1:
    40. 

  40. #    (sorry about latter).
    41. 

  41. # 6. Don't use [or hand-code with .byte] "rep ret." "ret" mnemonic is
    42. 

  42. #    required to identify the spots, where to inject Win64 epilogue!
    43. 

  43. #    But on the pros, it's then prefixed with rep automatically:-)
    44. 

  44. # 7. Stick to explicit ip-relative addressing. If you have to use
    45. 

  45. #    GOTPCREL addressing, stick to mov symbol@GOTPCREL(%rip),%r??.
    46. 

  46. #    Both are recognized and translated to proper Win64 addressing
    47. 

  47. #    modes. To support legacy code a synthetic directive, .picmeup,
    48. 

  48. #    is implemented. It puts address of the *next* instruction into
    49. 

  49. #    target register, e.g.:
    50. 

  50. #
    51. 

  51. #		.picmeup	%rax
    52. 

  52. #		lea		.Label-.(%rax),%rax
    53. 

  53. #
    54. 

  54. # 8. In order to provide for structured exception handling unified
    55. 

  55. #    Win64 prologue copies %rsp value to %rax. For further details
    56. 

  56. #    see SEH paragraph at the end.
    57. 

  57. # 9. .init segment is allowed to contain calls to functions only.
    58. 

  58. # a. If function accepts more than 4 arguments *and* >4th argument
    59. 

  59. #    is declared as non 64-bit value, do clear its upper part.
    60. 

  60. 
    61. 

  61. my $flavour = shift;
    62. 

  62. my $output  = shift;
    63. 

  63. if ($flavour =~ /\./) { $output = $flavour; undef $flavour; }
    64. 

  64. 

  65. open STDOUT,">$output" || die "can't open $output: $!"
    66. 

  66. 	if (defined($output));
    67. 

  67. 

  68. my $gas=1;	$gas=0 if ($output =~ /\.asm$/);
    69. 

  69. my $elf=1;	$elf=0 if (!$gas);
    70. 

  70. my $win64=0;
    71. 

  71. my $prefix="";
    72. 

  72. my $decor=".L";
    73. 

  73. 

  74. my $masmref=8 + 50727*2**-32;	# 8.00.50727 shipped with VS2005
    75. 

  75. my $masm=0;
    76. 

  76. my $PTR=" PTR";
    77. 

  77. 

  78. my $nasmref=2.03;
    79. 

  79. my $nasm=0;
    80. 

  80. 

  81. if    ($flavour eq "mingw64")	{ $gas=1; $elf=0; $win64=1;
    82. 

  82. 				  $prefix=`echo __USER_LABEL_PREFIX__ | $ENV{CC} -E -P -`;
    83. 

  83. 				  chomp($prefix);
    84. 

  84. 				}
    85. 

  85. elsif ($flavour eq "macosx")	{ $gas=1; $elf=0; $prefix="_"; $decor="L\$"; }
    86. 

  86. elsif ($flavour eq "masm")	{ $gas=0; $elf=0; $masm=$masmref; $win64=1; $decor="\$L\$"; }
    87. 

  87. elsif ($flavour eq "nasm")	{ $gas=0; $elf=0; $nasm=$nasmref; $win64=1; $decor="\$L\$"; $PTR=""; }
    88. 

  88. elsif (!$gas)
    89. 

  89. {   if ($ENV{ASM} =~ m/nasm/ && `nasm -v` =~ m/version ([0-9]+)\.([0-9]+)/i)
    90. 

  90.     {	$nasm = $1 + $2*0.01; $PTR="";  }
    91. 

  91.     elsif (`ml64 2>&1` =~ m/Version ([0-9]+)\.([0-9]+)(\.([0-9]+))?/)
    92. 

  92.     {	$masm = $1 + $2*2**-16 + $4*2**-32;   }
    93. 

  93.     die "no assembler found on %PATH" if (!($nasm || $masm));
    94. 

  94.     $win64=1;
    95. 

  95.     $elf=0;
    96. 

  96.     $decor="\$L\$";
    97. 

  97. }
    98. 

  98. 

  99. my $current_segment;
    100. 

  100. my $current_function;
    101. 

  101. my %globals;
    102. 

  102. 

  103. { package opcode;	# pick up opcodes
    104. 

  104.     sub re {
    105. 

  105. 	my	$self = shift;	# single instance in enough...
    106. 

  106. 	local	*line = shift;
    107. 

  107. 	undef	$ret;
    108. 

  108. 

  109. 	if ($line =~ /^([a-z][a-z0-9]*)/i) {
    110. 

  110. 	    $self->{op} = $1;
    111. 

  111. 	    $ret = $self;
    112. 

  112. 	    $line = substr($line,@+[0]); $line =~ s/^\s+//;
    113. 

  113. 

  114. 	    undef $self->{sz};
    115. 

  115. 	    if ($self->{op} =~ /^(movz)x?([bw]).*/) {	# movz is pain...
    116. 

  116. 		$self->{op} = $1;
    117. 

  117. 		$self->{sz} = $2;
    118. 

  118. 	    } elsif ($self->{op} =~ /call|jmp/) {
    119. 

  119. 		$self->{sz} = "";
    120. 

  120. 	    } elsif ($self->{op} =~ /^p/ && $' !~ /^(ush|op|insrw)/) { # SSEn
    121. 

  121. 		$self->{sz} = "";
    122. 

  122. 	    } elsif ($self->{op} =~ /^v/) { # VEX
    123. 

  123. 		$self->{sz} = "";
    124. 

  124. 	    } elsif ($self->{op} =~ /movq/ && $line =~ /%xmm/) {
    125. 

  125. 		$self->{sz} = "";
    126. 

  126. 	    } elsif ($self->{op} =~ /([a-z]{3,})([qlwb])$/) {
    127. 

  127. 		$self->{op} = $1;
    128. 

  128. 		$self->{sz} = $2;
    129. 

  129. 	    }
    130. 

  130. 	}
    131. 

  131. 	$ret;
    132. 

  132.     }
    133. 

  133.     sub size {
    134. 

  134. 	my $self = shift;
    135. 

  135. 	my $sz   = shift;
    136. 

  136. 	$self->{sz} = $sz if (defined($sz) && !defined($self->{sz}));
    137. 

  137. 	$self->{sz};
    138. 

  138.     }
    139. 

  139.     sub out {
    140. 

  140. 	my $self = shift;
    141. 

  141. 	if ($gas) {
    142. 

  142. 	    if ($self->{op} eq "movz") {	# movz is pain...
    143. 

  143. 		sprintf "%s%s%s",$self->{op},$self->{sz},shift;
    144. 

  144. 	    } elsif ($self->{op} =~ /^set/) { 
    145. 

  145. 		"$self->{op}";
    146. 

  146. 	    } elsif ($self->{op} eq "ret") {
    147. 

  147. 		my $epilogue = "";
    148. 

  148. 		if ($win64 && $current_function->{abi} eq "svr4") {
    149. 

  149. 		    $epilogue = "movq	8(%rsp),%rdi\n\t" .
    150. 

  150. 				"movq	16(%rsp),%rsi\n\t";
    151. 

  151. 		}
    152. 

  152. 	    	$epilogue . ".byte	0xf3,0xc3";
    153. 

  153. 	    } elsif ($self->{op} eq "call" && !$elf && $current_segment eq ".init") {
    154. 

  154. 		".p2align\t3\n\t.quad";
    155. 

  155. 	    } else {
    156. 

  156. 		"$self->{op}$self->{sz}";
    157. 

  157. 	    }
    158. 

  158. 	} else {
    159. 

  159. 	    $self->{op} =~ s/^movz/movzx/;
    160. 

  160. 	    if ($self->{op} eq "ret") {
    161. 

  161. 		$self->{op} = "";
    162. 

  162. 		if ($win64 && $current_function->{abi} eq "svr4") {
    163. 

  163. 		    $self->{op} = "mov	rdi,QWORD${PTR}[8+rsp]\t;WIN64 epilogue\n\t".
    164. 

  164. 				  "mov	rsi,QWORD${PTR}[16+rsp]\n\t";
    165. 

  165. 	    	}
    166. 

  166. 		$self->{op} .= "DB\t0F3h,0C3h\t\t;repret";
    167. 

  167. 	    } elsif ($self->{op} =~ /^(pop|push)f/) {
    168. 

  168. 		$self->{op} .= $self->{sz};
    169. 

  169. 	    } elsif ($self->{op} eq "call" && $current_segment eq ".CRT\$XCU") {
    170. 

  170. 		$self->{op} = "\tDQ";
    171. 

  171. 	    } 
    172. 

  172. 	    $self->{op};
    173. 

  173. 	}
    174. 

  174.     }
    175. 

  175.     sub mnemonic {
    176. 

  176. 	my $self=shift;
    177. 

  177. 	my $op=shift;
    178. 

  178. 	$self->{op}=$op if (defined($op));
    179. 

  179. 	$self->{op};
    180. 

  180.     }
    181. 

  181. }
    182. 

  182. { package const;	# pick up constants, which start with $
    183. 

  183.     sub re {
    184. 

  184. 	my	$self = shift;	# single instance in enough...
    185. 

  185. 	local	*line = shift;
    186. 

  186. 	undef	$ret;
    187. 

  187. 

  188. 	if ($line =~ /^\$([^,]+)/) {
    189. 

  189. 	    $self->{value} = $1;
    190. 

  190. 	    $ret = $self;
    191. 

  191. 	    $line = substr($line,@+[0]); $line =~ s/^\s+//;
    192. 

  192. 	}
    193. 

  193. 	$ret;
    194. 

  194.     }
    195. 

  195.     sub out {
    196. 

  196.     	my $self = shift;
    197. 

  197. 

  198. 	if ($gas) {
    199. 

  199. 	    # Solaris /usr/ccs/bin/as can't handle multiplications
    200. 

  200. 	    # in $self->{value}
    201. 

  201. 	    $self->{value} =~ s/(?<![\w\$\.])(0x?[0-9a-f]+)/oct($1)/egi;
    202. 

  202. 	    $self->{value} =~ s/([0-9]+\s*[\*\/\%]\s*[0-9]+)/eval($1)/eg;
    203. 

  203. 	    sprintf "\$%s",$self->{value};
    204. 

  204. 	} else {
    205. 

  205. 	    $self->{value} =~ s/(0b[0-1]+)/oct($1)/eig;
    206. 

  206. 	    $self->{value} =~ s/0x([0-9a-f]+)/0$1h/ig if ($masm);
    207. 

  207. 	    sprintf "%s",$self->{value};
    208. 

  208. 	}
    209. 

  209.     }
    210. 

  210. }
    211. 

  211. { package ea;		# pick up effective addresses: expr(%reg,%reg,scale)
    212. 

  212.     sub re {
    213. 

  213. 	my	$self = shift;	# single instance in enough...
    214. 

  214. 	local	*line = shift;
    215. 

  215. 	undef	$ret;
    216. 

  216. 

  217. 	# optional * ---vvv--- appears in indirect jmp/call
    218. 

  218. 	if ($line =~ /^(\*?)([^\(,]*)\(([%\w,]+)\)/) {
    219. 

  219. 	    $self->{asterisk} = $1;
    220. 

  220. 	    $self->{label} = $2;
    221. 

  221. 	    ($self->{base},$self->{index},$self->{scale})=split(/,/,$3);
    222. 

  222. 	    $self->{scale} = 1 if (!defined($self->{scale}));
    223. 

  223. 	    $ret = $self;
    224. 

  224. 	    $line = substr($line,@+[0]); $line =~ s/^\s+//;
    225. 

  225. 

  226. 	    if ($win64 && $self->{label} =~ s/\@GOTPCREL//) {
    227. 

  227. 		die if (opcode->mnemonic() ne "mov");
    228. 

  228. 		opcode->mnemonic("lea");
    229. 

  229. 	    }
    230. 

  230. 	    $self->{base}  =~ s/^%//;
    231. 

  231. 	    $self->{index} =~ s/^%// if (defined($self->{index}));
    232. 

  232. 	}
    233. 

  233. 	$ret;
    234. 

  234.     }
    235. 

  235.     sub size {}
    236. 

  236.     sub out {
    237. 

  237.     	my $self = shift;
    238. 

  238. 	my $sz = shift;
    239. 

  239. 

  240. 	$self->{label} =~ s/([_a-z][_a-z0-9]*)/$globals{$1} or $1/gei;
    241. 

  241. 	$self->{label} =~ s/\.L/$decor/g;
    242. 

  242. 

  243. 	# Silently convert all EAs to 64-bit. This is required for
    244. 

  244. 	# elder GNU assembler and results in more compact code,
    245. 

  245. 	# *but* most importantly AES module depends on this feature!
    246. 

  246. 	$self->{index} =~ s/^[er](.?[0-9xpi])[d]?$/r\1/;
    247. 

  247. 	$self->{base}  =~ s/^[er](.?[0-9xpi])[d]?$/r\1/;
    248. 

  248. 

  249. 	# Solaris /usr/ccs/bin/as can't handle multiplications
    250. 

  250. 	# in $self->{label}, new gas requires sign extension...
    251. 

  251. 	use integer;
    252. 

  252. 	$self->{label} =~ s/(?<![\w\$\.])(0x?[0-9a-f]+)/oct($1)/egi;
    253. 

  253. 	$self->{label} =~ s/([0-9]+\s*[\*\/\%]\s*[0-9]+)/eval($1)/eg;
    254. 

  254. 	$self->{label} =~ s/([0-9]+)/$1<<32>>32/eg;
    255. 

  255. 

  256. 	if ($gas) {
    257. 

  257. 	    $self->{label} =~ s/^___imp_/__imp__/   if ($flavour eq "mingw64");
    258. 

  258. 

  259. 	    if (defined($self->{index})) {
    260. 

  260. 		sprintf "%s%s(%s,%%%s,%d)",$self->{asterisk},
    261. 

  261. 					$self->{label},
    262. 

  262. 					$self->{base}?"%$self->{base}":"",
    263. 

  263. 					$self->{index},$self->{scale};
    264. 

  264. 	    } else {
    265. 

  265. 		sprintf "%s%s(%%%s)",	$self->{asterisk},$self->{label},$self->{base};
    266. 

  266. 	    }
    267. 

  267. 	} else {
    268. 

  268. 	    %szmap = (	b=>"BYTE$PTR", w=>"WORD$PTR", l=>"DWORD$PTR",
    269. 

  269. 	    		q=>"QWORD$PTR",o=>"OWORD$PTR",x=>"XMMWORD$PTR" );
    270. 

  270. 

  271. 	    $self->{label} =~ s/\./\$/g;
    272. 

  272. 	    $self->{label} =~ s/(?<![\w\$\.])0x([0-9a-f]+)/0$1h/ig;
    273. 

  273. 	    $self->{label} = "($self->{label})" if ($self->{label} =~ /[\*\+\-\/]/);
    274. 

  274. 	    $sz="q" if ($self->{asterisk} || opcode->mnemonic() eq "movq");
    275. 

  275. 	    $sz="l" if (opcode->mnemonic() eq "movd");
    276. 

  276. 

  277. 	    if (defined($self->{index})) {
    278. 

  278. 		sprintf "%s[%s%s*%d%s]",$szmap{$sz},
    279. 

  279. 					$self->{label}?"$self->{label}+":"",
    280. 

  280. 					$self->{index},$self->{scale},
    281. 

  281. 					$self->{base}?"+$self->{base}":"";
    282. 

  282. 	    } elsif ($self->{base} eq "rip") {
    283. 

  283. 		sprintf "%s[%s]",$szmap{$sz},$self->{label};
    284. 

  284. 	    } else {
    285. 

  285. 		sprintf "%s[%s%s]",$szmap{$sz},
    286. 

  286. 					$self->{label}?"$self->{label}+":"",
    287. 

  287. 					$self->{base};
    288. 

  288. 	    }
    289. 

  289. 	}
    290. 

  290.     }
    291. 

  291. }
    292. 

  292. { package register;	# pick up registers, which start with %.
    293. 

  293.     sub re {
    294. 

  294. 	my	$class = shift;	# muliple instances...
    295. 

  295. 	my	$self = {};
    296. 

  296. 	local	*line = shift;
    297. 

  297. 	undef	$ret;
    298. 

  298. 

  299. 	# optional * ---vvv--- appears in indirect jmp/call
    300. 

  300. 	if ($line =~ /^(\*?)%(\w+)/) {
    301. 

  301. 	    bless $self,$class;
    302. 

  302. 	    $self->{asterisk} = $1;
    303. 

  303. 	    $self->{value} = $2;
    304. 

  304. 	    $ret = $self;
    305. 

  305. 	    $line = substr($line,@+[0]); $line =~ s/^\s+//;
    306. 

  306. 	}
    307. 

  307. 	$ret;
    308. 

  308.     }
    309. 

  309.     sub size {
    310. 

  310. 	my	$self = shift;
    311. 

  311. 	undef	$ret;
    312. 

  312. 

  313. 	if    ($self->{value} =~ /^r[\d]+b$/i)	{ $ret="b"; }
    314. 

  314. 	elsif ($self->{value} =~ /^r[\d]+w$/i)	{ $ret="w"; }
    315. 

  315. 	elsif ($self->{value} =~ /^r[\d]+d$/i)	{ $ret="l"; }
    316. 

  316. 	elsif ($self->{value} =~ /^r[\w]+$/i)	{ $ret="q"; }
    317. 

  317. 	elsif ($self->{value} =~ /^[a-d][hl]$/i){ $ret="b"; }
    318. 

  318. 	elsif ($self->{value} =~ /^[\w]{2}l$/i)	{ $ret="b"; }
    319. 

  319. 	elsif ($self->{value} =~ /^[\w]{2}$/i)	{ $ret="w"; }
    320. 

  320. 	elsif ($self->{value} =~ /^e[a-z]{2}$/i){ $ret="l"; }
    321. 

  321. 

  322. 	$ret;
    323. 

  323.     }
    324. 

  324.     sub out {
    325. 

  325.     	my $self = shift;
    326. 

  326. 	if ($gas)	{ sprintf "%s%%%s",$self->{asterisk},$self->{value}; }
    327. 

  327. 	else		{ $self->{value}; }
    328. 

  328.     }
    329. 

  329. }
    330. 

  330. { package label;	# pick up labels, which end with :
    331. 

  331.     sub re {
    332. 

  332. 	my	$self = shift;	# single instance is enough...
    333. 

  333. 	local	*line = shift;
    334. 

  334. 	undef	$ret;
    335. 

  335. 

  336. 	if ($line =~ /(^[\.\w]+)\:/) {
    337. 

  337. 	    $self->{value} = $1;
    338. 

  338. 	    $ret = $self;
    339. 

  339. 	    $line = substr($line,@+[0]); $line =~ s/^\s+//;
    340. 

  340. 

  341. 	    $self->{value} =~ s/^\.L/$decor/;
    342. 

  342. 	}
    343. 

  343. 	$ret;
    344. 

  344.     }
    345. 

  345.     sub out {
    346. 

  346. 	my $self = shift;
    347. 

  347. 

  348. 	if ($gas) {
    349. 

  349. 	    my $func = ($globals{$self->{value}} or $self->{value}) . ":";
    350. 

  350. 	    if ($win64	&&
    351. 

  351. 			$current_function->{name} eq $self->{value} &&
    352. 

  352. 			$current_function->{abi} eq "svr4") {
    353. 

  353. 		$func .= "\n";
    354. 

  354. 		$func .= "	movq	%rdi,8(%rsp)\n";
    355. 

  355. 		$func .= "	movq	%rsi,16(%rsp)\n";
    356. 

  356. 		$func .= "	movq	%rsp,%rax\n";
    357. 

  357. 		$func .= "${decor}SEH_begin_$current_function->{name}:\n";
    358. 

  358. 		my $narg = $current_function->{narg};
    359. 

  359. 		$narg=6 if (!defined($narg));
    360. 

  360. 		$func .= "	movq	%rcx,%rdi\n" if ($narg>0);
    361. 

  361. 		$func .= "	movq	%rdx,%rsi\n" if ($narg>1);
    362. 

  362. 		$func .= "	movq	%r8,%rdx\n"  if ($narg>2);
    363. 

  363. 		$func .= "	movq	%r9,%rcx\n"  if ($narg>3);
    364. 

  364. 		$func .= "	movq	40(%rsp),%r8\n" if ($narg>4);
    365. 

  365. 		$func .= "	movq	48(%rsp),%r9\n" if ($narg>5);
    366. 

  366. 	    }
    367. 

  367. 	    $func;
    368. 

  368. 	} elsif ($self->{value} ne "$current_function->{name}") {
    369. 

  369. 	    $self->{value} .= ":" if ($masm && $ret!~m/^\$/);
    370. 

  370. 	    $self->{value} . ":";
    371. 

  371. 	} elsif ($win64 && $current_function->{abi} eq "svr4") {
    372. 

  372. 	    my $func =	"$current_function->{name}" .
    373. 

  373. 			($nasm ? ":" : "\tPROC $current_function->{scope}") .
    374. 

  374. 			"\n";
    375. 

  375. 	    $func .= "	mov	QWORD${PTR}[8+rsp],rdi\t;WIN64 prologue\n";
    376. 

  376. 	    $func .= "	mov	QWORD${PTR}[16+rsp],rsi\n";
    377. 

  377. 	    $func .= "	mov	rax,rsp\n";
    378. 

  378. 	    $func .= "${decor}SEH_begin_$current_function->{name}:";
    379. 

  379. 	    $func .= ":" if ($masm);
    380. 

  380. 	    $func .= "\n";
    381. 

  381. 	    my $narg = $current_function->{narg};
    382. 

  382. 	    $narg=6 if (!defined($narg));
    383. 

  383. 	    $func .= "	mov	rdi,rcx\n" if ($narg>0);
    384. 

  384. 	    $func .= "	mov	rsi,rdx\n" if ($narg>1);
    385. 

  385. 	    $func .= "	mov	rdx,r8\n"  if ($narg>2);
    386. 

  386. 	    $func .= "	mov	rcx,r9\n"  if ($narg>3);
    387. 

  387. 	    $func .= "	mov	r8,QWORD${PTR}[40+rsp]\n" if ($narg>4);
    388. 

  388. 	    $func .= "	mov	r9,QWORD${PTR}[48+rsp]\n" if ($narg>5);
    389. 

  389. 	    $func .= "\n";
    390. 

  390. 	} else {
    391. 

  391. 	   "$current_function->{name}".
    392. 

  392. 			($nasm ? ":" : "\tPROC $current_function->{scope}");
    393. 

  393. 	}
    394. 

  394.     }
    395. 

  395. }
    396. 

  396. { package expr;		# pick up expressioins
    397. 

  397.     sub re {
    398. 

  398. 	my	$self = shift;	# single instance is enough...
    399. 

  399. 	local	*line = shift;
    400. 

  400. 	undef	$ret;
    401. 

  401. 

  402. 	if ($line =~ /(^[^,]+)/) {
    403. 

  403. 	    $self->{value} = $1;
    404. 

  404. 	    $ret = $self;
    405. 

  405. 	    $line = substr($line,@+[0]); $line =~ s/^\s+//;
    406. 

  406. 

  407. 	    $self->{value} =~ s/\@PLT// if (!$elf);
    408. 

  408. 	    $self->{value} =~ s/([_a-z][_a-z0-9]*)/$globals{$1} or $1/gei;
    409. 

  409. 	    $self->{value} =~ s/\.L/$decor/g;
    410. 

  410. 	}
    411. 

  411. 	$ret;
    412. 

  412.     }
    413. 

  413.     sub out {
    414. 

  414. 	my $self = shift;
    415. 

  415. 	if ($nasm && opcode->mnemonic()=~m/^j/) {
    416. 

  416. 	    "NEAR ".$self->{value};
    417. 

  417. 	} else {
    418. 

  418. 	    $self->{value};
    419. 

  419. 	}
    420. 

  420.     }
    421. 

  421. }
    422. 

  422. { package directive;	# pick up directives, which start with .
    423. 

  423.     sub re {
    424. 

  424. 	my	$self = shift;	# single instance is enough...
    425. 

  425. 	local	*line = shift;
    426. 

  426. 	undef	$ret;
    427. 

  427. 	my	$dir;
    428. 

  428. 	my	%opcode =	# lea 2f-1f(%rip),%dst; 1: nop; 2:
    429. 

  429. 		(	"%rax"=>0x01058d48,	"%rcx"=>0x010d8d48,
    430. 

  430. 			"%rdx"=>0x01158d48,	"%rbx"=>0x011d8d48,
    431. 

  431. 			"%rsp"=>0x01258d48,	"%rbp"=>0x012d8d48,
    432. 

  432. 			"%rsi"=>0x01358d48,	"%rdi"=>0x013d8d48,
    433. 

  433. 			"%r8" =>0x01058d4c,	"%r9" =>0x010d8d4c,
    434. 

  434. 			"%r10"=>0x01158d4c,	"%r11"=>0x011d8d4c,
    435. 

  435. 			"%r12"=>0x01258d4c,	"%r13"=>0x012d8d4c,
    436. 

  436. 			"%r14"=>0x01358d4c,	"%r15"=>0x013d8d4c	);
    437. 

  437. 

  438. 	if ($line =~ /^\s*(\.\w+)/) {
    439. 

  439. 	    $dir = $1;
    440. 

  440. 	    $ret = $self;
    441. 

  441. 	    undef $self->{value};
    442. 

  442. 	    $line = substr($line,@+[0]); $line =~ s/^\s+//;
    443. 

  443. 

  444. 	    SWITCH: for ($dir) {
    445. 

  445. 		/\.picmeup/ && do { if ($line =~ /(%r[\w]+)/i) {
    446. 

  446. 			    		$dir="\t.long";
    447. 

  447. 					$line=sprintf "0x%x,0x90000000",$opcode{$1};
    448. 

  448. 				    }
    449. 

  449. 				    last;
    450. 

  450. 				  };
    451. 

  451. 		/\.global|\.globl|\.extern/
    452. 

  452. 			    && do { $globals{$line} = $prefix . $line;
    453. 

  453. 				    $line = $globals{$line} if ($prefix);
    454. 

  454. 				    last;
    455. 

  455. 				  };
    456. 

  456. 		/\.type/    && do { ($sym,$type,$narg) = split(',',$line);
    457. 

  457. 				    if ($type eq "\@function") {
    458. 

  458. 					undef $current_function;
    459. 

  459. 					$current_function->{name} = $sym;
    460. 

  460. 					$current_function->{abi}  = "svr4";
    461. 

  461. 					$current_function->{narg} = $narg;
    462. 

  462. 					$current_function->{scope} = defined($globals{$sym})?"PUBLIC":"PRIVATE";
    463. 

  463. 				    } elsif ($type eq "\@abi-omnipotent") {
    464. 

  464. 					undef $current_function;
    465. 

  465. 					$current_function->{name} = $sym;
    466. 

  466. 					$current_function->{scope} = defined($globals{$sym})?"PUBLIC":"PRIVATE";
    467. 

  467. 				    }
    468. 

  468. 				    $line =~ s/\@abi\-omnipotent/\@function/;
    469. 

  469. 				    $line =~ s/\@function.*/\@function/;
    470. 

  470. 				    last;
    471. 

  471. 				  };
    472. 

  472. 		/\.asciz/   && do { if ($line =~ /^"(.*)"$/) {
    473. 

  473. 					$dir  = ".byte";
    474. 

  474. 					$line = join(",",unpack("C*",$1),0);
    475. 

  475. 				    }
    476. 

  476. 				    last;
    477. 

  477. 				  };
    478. 

  478. 		/\.rva|\.long|\.quad/
    479. 

  479. 			    && do { $line =~ s/([_a-z][_a-z0-9]*)/$globals{$1} or $1/gei;
    480. 

  480. 				    $line =~ s/\.L/$decor/g;
    481. 

  481. 				    last;
    482. 

  482. 				  };
    483. 

  483. 	    }
    484. 

  484. 

  485. 	    if ($gas) {
    486. 

  486. 		$self->{value} = $dir . "\t" . $line;
    487. 

  487. 

  488. 		if ($dir =~ /\.extern/) {
    489. 

  489. 		    $self->{value} = ""; # swallow extern
    490. 

  490. 		} elsif (!$elf && $dir =~ /\.type/) {
    491. 

  491. 		    $self->{value} = "";
    492. 

  492. 		    $self->{value} = ".def\t" . ($globals{$1} or $1) . ";\t" .
    493. 

  493. 				(defined($globals{$1})?".scl 2;":".scl 3;") .
    494. 

  494. 				"\t.type 32;\t.endef"
    495. 

  495. 				if ($win64 && $line =~ /([^,]+),\@function/);
    496. 

  496. 		} elsif (!$elf && $dir =~ /\.size/) {
    497. 

  497. 		    $self->{value} = "";
    498. 

  498. 		    if (defined($current_function)) {
    499. 

  499. 			$self->{value} .= "${decor}SEH_end_$current_function->{name}:"
    500. 

  500. 				if ($win64 && $current_function->{abi} eq "svr4");
    501. 

  501. 			undef $current_function;
    502. 

  502. 		    }
    503. 

  503. 		} elsif (!$elf && $dir =~ /\.align/) {
    504. 

  504. 		    $self->{value} = ".p2align\t" . (log($line)/log(2));
    505. 

  505. 		} elsif ($dir eq ".section") {
    506. 

  506. 		    $current_segment=$line;
    507. 

  507. 		    if (!$elf && $current_segment eq ".init") {
    508. 

  508. 			if	($flavour eq "macosx")	{ $self->{value} = ".mod_init_func"; }
    509. 

  509. 			elsif	($flavour eq "mingw64")	{ $self->{value} = ".section\t.ctors"; }
    510. 

  510. 		    }
    511. 

  511. 		} elsif ($dir =~ /\.(text|data)/) {
    512. 

  512. 		    $current_segment=".$1";
    513. 

  513. 		} elsif ($dir =~ /\.hidden/) {
    514. 

  514. 		    if    ($flavour eq "macosx")  { $self->{value} = ".private_extern\t$prefix$line"; }
    515. 

  515. 		    elsif ($flavour eq "mingw64") { $self->{value} = ""; }
    516. 

  516. 		} elsif ($dir =~ /\.comm/) {
    517. 

  517. 		    $self->{value} = "$dir\t$prefix$line";
    518. 

  518. 		    $self->{value} =~ s|,([0-9]+),([0-9]+)$|",$1,".log($2)/log(2)|e if ($flavour eq "macosx");
    519. 

  519. 		}
    520. 

  520. 		$line = "";
    521. 

  521. 		return $self;
    522. 

  522. 	    }
    523. 

  523. 

  524. 	    # non-gas case or nasm/masm
    525. 

  525. 	    SWITCH: for ($dir) {
    526. 

  526. 		/\.text/    && do { my $v=undef;
    527. 

  527. 				    if ($nasm) {
    528. 

  528. 					$v="section	.text code align=64\n";
    529. 

  529. 				    } else {
    530. 

  530. 					$v="$current_segment\tENDS\n" if ($current_segment);
    531. 

  531. 					$current_segment = ".text\$";
    532. 

  532. 					$v.="$current_segment\tSEGMENT ";
    533. 

  533. 					$v.=$masm>=$masmref ? "ALIGN(64)" : "PAGE";
    534. 

  534. 					$v.=" 'CODE'";
    535. 

  535. 				    }
    536. 

  536. 				    $self->{value} = $v;
    537. 

  537. 				    last;
    538. 

  538. 				  };
    539. 

  539. 		/\.data/    && do { my $v=undef;
    540. 

  540. 				    if ($nasm) {
    541. 

  541. 					$v="section	.data data align=8\n";
    542. 

  542. 				    } else {
    543. 

  543. 					$v="$current_segment\tENDS\n" if ($current_segment);
    544. 

  544. 					$current_segment = "_DATA";
    545. 

  545. 					$v.="$current_segment\tSEGMENT";
    546. 

  546. 				    }
    547. 

  547. 				    $self->{value} = $v;
    548. 

  548. 				    last;
    549. 

  549. 				  };
    550. 

  550. 		/\.section/ && do { my $v=undef;
    551. 

  551. 				    $line =~ s/([^,]*).*/$1/;
    552. 

  552. 				    $line = ".CRT\$XCU" if ($line eq ".init");
    553. 

  553. 				    if ($nasm) {
    554. 

  554. 					$v="section	$line";
    555. 

  555. 					if ($line=~/\.([px])data/) {
    556. 

  556. 					    $v.=" rdata align=";
    557. 

  557. 					    $v.=$1 eq "p"? 4 : 8;
    558. 

  558. 					} elsif ($line=~/\.CRT\$/i) {
    559. 

  559. 					    $v.=" rdata align=8";
    560. 

  560. 					}
    561. 

  561. 				    } else {
    562. 

  562. 					$v="$current_segment\tENDS\n" if ($current_segment);
    563. 

  563. 					$v.="$line\tSEGMENT";
    564. 

  564. 					if ($line=~/\.([px])data/) {
    565. 

  565. 					    $v.=" READONLY";
    566. 

  566. 					    $v.=" ALIGN(".($1 eq "p" ? 4 : 8).")" if ($masm>=$masmref);
    567. 

  567. 					} elsif ($line=~/\.CRT\$/i) {
    568. 

  568. 					    $v.=" READONLY ";
    569. 

  569. 					    $v.=$masm>=$masmref ? "ALIGN(8)" : "DWORD";
    570. 

  570. 					}
    571. 

  571. 				    }
    572. 

  572. 				    $current_segment = $line;
    573. 

  573. 				    $self->{value} = $v;
    574. 

  574. 				    last;
    575. 

  575. 				  };
    576. 

  576. 		/\.extern/  && do { $self->{value}  = "EXTERN\t".$line;
    577. 

  577. 				    $self->{value} .= ":NEAR" if ($masm);
    578. 

  578. 				    last;
    579. 

  579. 				  };
    580. 

  580. 		/\.globl|.global/
    581. 

  581. 			    && do { $self->{value}  = $masm?"PUBLIC":"global";
    582. 

  582. 				    $self->{value} .= "\t".$line;
    583. 

  583. 				    last;
    584. 

  584. 				  };
    585. 

  585. 		/\.size/    && do { if (defined($current_function)) {
    586. 

  586. 					undef $self->{value};
    587. 

  587. 					if ($current_function->{abi} eq "svr4") {
    588. 

  588. 					    $self->{value}="${decor}SEH_end_$current_function->{name}:";
    589. 

  589. 					    $self->{value}.=":\n" if($masm);
    590. 

  590. 					}
    591. 

  591. 					$self->{value}.="$current_function->{name}\tENDP" if($masm && $current_function->{name});
    592. 

  592. 					undef $current_function;
    593. 

  593. 				    }
    594. 

  594. 				    last;
    595. 

  595. 				  };
    596. 

  596. 		/\.align/   && do { $self->{value} = "ALIGN\t".$line; last; };
    597. 

  597. 		/\.(value|long|rva|quad)/
    598. 

  598. 			    && do { my $sz  = substr($1,0,1);
    599. 

  599. 				    my @arr = split(/,\s*/,$line);
    600. 

  600. 				    my $last = pop(@arr);
    601. 

  601. 				    my $conv = sub  {	my $var=shift;
    602. 

  602. 							$var=~s/^(0b[0-1]+)/oct($1)/eig;
    603. 

  603. 							$var=~s/^0x([0-9a-f]+)/0$1h/ig if ($masm);
    604. 

  604. 							if ($sz eq "D" && ($current_segment=~/.[px]data/ || $dir eq ".rva"))
    605. 

  605. 							{ $var=~s/([_a-z\$\@][_a-z0-9\$\@]*)/$nasm?"$1 wrt ..imagebase":"imagerel $1"/egi; }
    606. 

  606. 							$var;
    607. 

  607. 						    };  
    608. 

  608. 

  609. 				    $sz =~ tr/bvlrq/BWDDQ/;
    610. 

  610. 				    $self->{value} = "\tD$sz\t";
    611. 

  611. 				    for (@arr) { $self->{value} .= &$conv($_).","; }
    612. 

  612. 				    $self->{value} .= &$conv($last);
    613. 

  613. 				    last;
    614. 

  614. 				  };
    615. 

  615. 		/\.byte/    && do { my @str=split(/,\s*/,$line);
    616. 

  616. 				    map(s/(0b[0-1]+)/oct($1)/eig,@str);
    617. 

  617. 				    map(s/0x([0-9a-f]+)/0$1h/ig,@str) if ($masm);	
    618. 

  618. 				    while ($#str>15) {
    619. 

  619. 					$self->{value}.="DB\t"
    620. 

  620. 						.join(",",@str[0..15])."\n";
    621. 

  621. 					foreach (0..15) { shift @str; }
    622. 

  622. 				    }
    623. 

  623. 				    $self->{value}.="DB\t"
    624. 

  624. 						.join(",",@str) if (@str);
    625. 

  625. 				    last;
    626. 

  626. 				  };
    627. 

  627. 		/\.comm/    && do { my @str=split(/,\s*/,$line);
    628. 

  628. 				    my $v=undef;
    629. 

  629. 				    if ($nasm) {
    630. 

  630. 					$v.="common	$prefix@str[0] @str[1]";
    631. 

  631. 				    } else {
    632. 

  632. 					$v="$current_segment\tENDS\n" if ($current_segment);
    633. 

  633. 					$current_segment = "_DATA";
    634. 

  634. 					$v.="$current_segment\tSEGMENT\n";
    635. 

  635. 					$v.="COMM	@str[0]:DWORD:".@str[1]/4;
    636. 

  636. 				    }
    637. 

  637. 				    $self->{value} = $v;
    638. 

  638. 				    last;
    639. 

  639. 				  };
    640. 

  640. 	    }
    641. 

  641. 	    $line = "";
    642. 

  642. 	}
    643. 

  643. 

  644. 	$ret;
    645. 

  645.     }
    646. 

  646.     sub out {
    647. 

  647. 	my $self = shift;
    648. 

  648. 	$self->{value};
    649. 

  649.     }
    650. 

  650. }
    651. 

  651. 

  652. sub rex {
    653. 

  653.  local *opcode=shift;
    654. 

  654.  my ($dst,$src,$rex)=@_;
    655. 

  655. 

  656.    $rex|=0x04 if($dst>=8);
    657. 

  657.    $rex|=0x01 if($src>=8);
    658. 

  658.    push @opcode,($rex|0x40) if ($rex);
    659. 

  659. }
    660. 

  660. 

  661. # older gas and ml64 don't handle SSE>2 instructions
    662. 

  662. my %regrm = (	"%eax"=>0, "%ecx"=>1, "%edx"=>2, "%ebx"=>3,
    663. 

  663. 		"%esp"=>4, "%ebp"=>5, "%esi"=>6, "%edi"=>7	);
    664. 

  664. 

  665. my $movq = sub {	# elderly gas can't handle inter-register movq
    666. 

  666.   my $arg = shift;
    667. 

  667.   my @opcode=(0x66);
    668. 

  668.     if ($arg =~ /%xmm([0-9]+),\s*%r(\w+)/) {
    669. 

  669. 	my ($src,$dst)=($1,$2);
    670. 

  670. 	if ($dst !~ /[0-9]+/)	{ $dst = $regrm{"%e$dst"}; }
    671. 

  671. 	rex(\@opcode,$src,$dst,0x8);
    672. 

  672. 	push @opcode,0x0f,0x7e;
    673. 

  673. 	push @opcode,0xc0|(($src&7)<<3)|($dst&7);	# ModR/M
    674. 

  674. 	@opcode;
    675. 

  675.     } elsif ($arg =~ /%r(\w+),\s*%xmm([0-9]+)/) {
    676. 

  676. 	my ($src,$dst)=($2,$1);
    677. 

  677. 	if ($dst !~ /[0-9]+/)	{ $dst = $regrm{"%e$dst"}; }
    678. 

  678. 	rex(\@opcode,$src,$dst,0x8);
    679. 

  679. 	push @opcode,0x0f,0x6e;
    680. 

  680. 	push @opcode,0xc0|(($src&7)<<3)|($dst&7);	# ModR/M
    681. 

  681. 	@opcode;
    682. 

  682.     } else {
    683. 

  683. 	();
    684. 

  684.     }
    685. 

  685. };
    686. 

  686. 

  687. my $pextrd = sub {
    688. 

  688.     if (shift =~ /\$([0-9]+),\s*%xmm([0-9]+),\s*(%\w+)/) {
    689. 

  689.       my @opcode=(0x66);
    690. 

  690. 	$imm=$1;
    691. 

  691. 	$src=$2;
    692. 

  692. 	$dst=$3;
    693. 

  693. 	if ($dst =~ /%r([0-9]+)d/)	{ $dst = $1; }
    694. 

  694. 	elsif ($dst =~ /%e/)		{ $dst = $regrm{$dst}; }
    695. 

  695. 	rex(\@opcode,$src,$dst);
    696. 

  696. 	push @opcode,0x0f,0x3a,0x16;
    697. 

  697. 	push @opcode,0xc0|(($src&7)<<3)|($dst&7);	# ModR/M
    698. 

  698. 	push @opcode,$imm;
    699. 

  699. 	@opcode;
    700. 

  700.     } else {
    701. 

  701. 	();
    702. 

  702.     }
    703. 

  703. };
    704. 

  704. 

  705. my $pinsrd = sub {
    706. 

  706.     if (shift =~ /\$([0-9]+),\s*(%\w+),\s*%xmm([0-9]+)/) {
    707. 

  707.       my @opcode=(0x66);
    708. 

  708. 	$imm=$1;
    709. 

  709. 	$src=$2;
    710. 

  710. 	$dst=$3;
    711. 

  711. 	if ($src =~ /%r([0-9]+)/)	{ $src = $1; }
    712. 

  712. 	elsif ($src =~ /%e/)		{ $src = $regrm{$src}; }
    713. 

  713. 	rex(\@opcode,$dst,$src);
    714. 

  714. 	push @opcode,0x0f,0x3a,0x22;
    715. 

  715. 	push @opcode,0xc0|(($dst&7)<<3)|($src&7);	# ModR/M
    716. 

  716. 	push @opcode,$imm;
    717. 

  717. 	@opcode;
    718. 

  718.     } else {
    719. 

  719. 	();
    720. 

  720.     }
    721. 

  721. };
    722. 

  722. 

  723. my $pshufb = sub {
    724. 

  724.     if (shift =~ /%xmm([0-9]+),\s*%xmm([0-9]+)/) {
    725. 

  725.       my @opcode=(0x66);
    726. 

  726. 	rex(\@opcode,$2,$1);
    727. 

  727. 	push @opcode,0x0f,0x38,0x00;
    728. 

  728. 	push @opcode,0xc0|($1&7)|(($2&7)<<3);		# ModR/M
    729. 

  729. 	@opcode;
    730. 

  730.     } else {
    731. 

  731. 	();
    732. 

  732.     }
    733. 

  733. };
    734. 

  734. 

  735. my $palignr = sub {
    736. 

  736.     if (shift =~ /\$([0-9]+),\s*%xmm([0-9]+),\s*%xmm([0-9]+)/) {
    737. 

  737.       my @opcode=(0x66);
    738. 

  738. 	rex(\@opcode,$3,$2);
    739. 

  739. 	push @opcode,0x0f,0x3a,0x0f;
    740. 

  740. 	push @opcode,0xc0|($2&7)|(($3&7)<<3);		# ModR/M
    741. 

  741. 	push @opcode,$1;
    742. 

  742. 	@opcode;
    743. 

  743.     } else {
    744. 

  744. 	();
    745. 

  745.     }
    746. 

  746. };
    747. 

  747. 

  748. my $pclmulqdq = sub {
    749. 

  749.     if (shift =~ /\$([x0-9a-f]+),\s*%xmm([0-9]+),\s*%xmm([0-9]+)/) {
    750. 

  750.       my @opcode=(0x66);
    751. 

  751. 	rex(\@opcode,$3,$2);
    752. 

  752. 	push @opcode,0x0f,0x3a,0x44;
    753. 

  753. 	push @opcode,0xc0|($2&7)|(($3&7)<<3);		# ModR/M
    754. 

  754. 	my $c=$1;
    755. 

  755. 	push @opcode,$c=~/^0/?oct($c):$c;
    756. 

  756. 	@opcode;
    757. 

  757.     } else {
    758. 

  758. 	();
    759. 

  759.     }
    760. 

  760. };
    761. 

  761. 

  762. my $rdrand = sub {
    763. 

  763.     if (shift =~ /%[er](\w+)/) {
    764. 

  764.       my @opcode=();
    765. 

  765.       my $dst=$1;
    766. 

  766. 	if ($dst !~ /[0-9]+/) { $dst = $regrm{"%e$dst"}; }
    767. 

  767. 	rex(\@opcode,0,$1,8);
    768. 

  768. 	push @opcode,0x0f,0xc7,0xf0|($dst&7);
    769. 

  769. 	@opcode;
    770. 

  770.     } else {
    771. 

  771. 	();
    772. 

  772.     }
    773. 

  773. };
    774. 

  774. 

  775. if ($nasm) {
    776. 

  776.     print <<___;
    777. 

  777. default	rel
    778. 

  778. %define XMMWORD
    779. 

  779. ___
    780. 

  780. } elsif ($masm) {
    781. 

  781.     print <<___;
    782. 

  782. OPTION	DOTNAME
    783. 

  783. ___
    784. 

  784. }
    785. 

  785. while($line=<>) {
    786. 

  786. 

  787.     chomp($line);
    788. 

  788. 

  789.     $line =~ s|[#!].*$||;	# get rid of asm-style comments...
    790. 

  790.     $line =~ s|/\*.*\*/||;	# ... and C-style comments...
    791. 

  791.     $line =~ s|^\s+||;		# ... and skip white spaces in beginning
    792. 

  792. 

  793.     undef $label;
    794. 

  794.     undef $opcode;
    795. 

  795.     undef @args;
    796. 

  796. 

  797.     if ($label=label->re(\$line))	{ print $label->out(); }
    798. 

  798. 

  799.     if (directive->re(\$line)) {
    800. 

  800. 	printf "%s",directive->out();
    801. 

  801.     } elsif ($opcode=opcode->re(\$line)) {
    802. 

  802. 	my $asm = eval("\$".$opcode->mnemonic());
    803. 

  803. 	undef @bytes;
    804. 

  804. 	
    805. 

  805. 	if ((ref($asm) eq 'CODE') && scalar(@bytes=&$asm($line))) {
    806. 

  806. 	    print $gas?".byte\t":"DB\t",join(',',@bytes),"\n";
    807. 

  807. 	    next;
    808. 

  808. 	}
    809. 

  809. 

  810. 	ARGUMENT: while (1) {
    811. 

  811. 	my $arg;
    812. 

  812. 

  813. 	if ($arg=register->re(\$line))	{ opcode->size($arg->size()); }
    814. 

  814. 	elsif ($arg=const->re(\$line))	{ }
    815. 

  815. 	elsif ($arg=ea->re(\$line))	{ }
    816. 

  816. 	elsif ($arg=expr->re(\$line))	{ }
    817. 

  817. 	else				{ last ARGUMENT; }
    818. 

  818. 

  819. 	push @args,$arg;
    820. 

  820. 

  821. 	last ARGUMENT if ($line !~ /^,/);
    822. 

  822. 

  823. 	$line =~ s/^,\s*//;
    824. 

  824. 	} # ARGUMENT:
    825. 

  825. 

  826. 	if ($#args>=0) {
    827. 

  827. 	    my $insn;
    828. 

  828. 	    my $sz=opcode->size();
    829. 

  829. 

  830. 	    if ($gas) {
    831. 

  831. 		$insn = $opcode->out($#args>=1?$args[$#args]->size():$sz);
    832. 

  832. 		@args = map($_->out($sz),@args);
    833. 

  833. 		printf "\t%s\t%s",$insn,join(",",@args);
    834. 

  834. 	    } else {
    835. 

  835. 		$insn = $opcode->out();
    836. 

  836. 		foreach (@args) {
    837. 

  837. 		    my $arg = $_->out();
    838. 

  838. 		    # $insn.=$sz compensates for movq, pinsrw, ...
    839. 

  839. 		    if ($arg =~ /^xmm[0-9]+$/) { $insn.=$sz; $sz="x" if(!$sz); last; }
    840. 

  840. 		    if ($arg =~ /^mm[0-9]+$/)  { $insn.=$sz; $sz="q" if(!$sz); last; }
    841. 

  841. 		}
    842. 

  842. 		@args = reverse(@args);
    843. 

  843. 		undef $sz if ($nasm && $opcode->mnemonic() eq "lea");
    844. 

  844. 		printf "\t%s\t%s",$insn,join(",",map($_->out($sz),@args));
    845. 

  845. 	    }
    846. 

  846. 	} else {
    847. 

  847. 	    printf "\t%s",$opcode->out();
    848. 

  848. 	}
    849. 

  849.     }
    850. 

  850. 

  851.     print $line,"\n";
    852. 

  852. }
    853. 

  853. 

  854. print "\n$current_segment\tENDS\n"	if ($current_segment && $masm);
    855. 

  855. print "END\n"				if ($masm);
    856. 

  856. 

  857. close STDOUT;
    858. 

  858. 

  859. #################################################
    860. 

  860. # Cross-reference x86_64 ABI "card"
    861. 

  861. #
    862. 

  862. # 		Unix		Win64
    863. 

  863. # %rax		*		*
    864. 

  864. # %rbx		-		-
    865. 

  865. # %rcx		#4		#1
    866. 

  866. # %rdx		#3		#2
    867. 

  867. # %rsi		#2		-
    868. 

  868. # %rdi		#1		-
    869. 

  869. # %rbp		-		-
    870. 

  870. # %rsp		-		-
    871. 

  871. # %r8		#5		#3
    872. 

  872. # %r9		#6		#4
    873. 

  873. # %r10		*		*
    874. 

  874. # %r11		*		*
    875. 

  875. # %r12		-		-
    876. 

  876. # %r13		-		-
    877. 

  877. # %r14		-		-
    878. 

  878. # %r15		-		-
    879. 

  879. # 
    880. 

  880. # (*)	volatile register
    881. 

  881. # (-)	preserved by callee
    882. 

  882. # (#)	Nth argument, volatile
    883. 

  883. #
    884. 

  884. # In Unix terms top of stack is argument transfer area for arguments
    885. 

  885. # which could not be accomodated in registers. Or in other words 7th
    886. 

  886. # [integer] argument resides at 8(%rsp) upon function entry point.
    887. 

  887. # 128 bytes above %rsp constitute a "red zone" which is not touched
    888. 

  888. # by signal handlers and can be used as temporal storage without
    889. 

  889. # allocating a frame.
    890. 

  890. #
    891. 

  891. # In Win64 terms N*8 bytes on top of stack is argument transfer area,
    892. 

  892. # which belongs to/can be overwritten by callee. N is the number of
    893. 

  893. # arguments passed to callee, *but* not less than 4! This means that
    894. 

  894. # upon function entry point 5th argument resides at 40(%rsp), as well
    895. 

  895. # as that 32 bytes from 8(%rsp) can always be used as temporal
    896. 

  896. # storage [without allocating a frame]. One can actually argue that
    897. 

  897. # one can assume a "red zone" above stack pointer under Win64 as well.
    898. 

  898. # Point is that at apparently no occasion Windows kernel would alter
    899. 

  899. # the area above user stack pointer in true asynchronous manner...
    900. 

  900. #
    901. 

  901. # All the above means that if assembler programmer adheres to Unix
    902. 

  902. # register and stack layout, but disregards the "red zone" existense,
    903. 

  903. # it's possible to use following prologue and epilogue to "gear" from
    904. 

  904. # Unix to Win64 ABI in leaf functions with not more than 6 arguments.
    905. 

  905. #
    906. 

  906. # omnipotent_function:
    907. 

  907. # ifdef WIN64
    908. 

  908. #	movq	%rdi,8(%rsp)
    909. 

  909. #	movq	%rsi,16(%rsp)
    910. 

  910. #	movq	%rcx,%rdi	; if 1st argument is actually present
    911. 

  911. #	movq	%rdx,%rsi	; if 2nd argument is actually ...
    912. 

  912. #	movq	%r8,%rdx	; if 3rd argument is ...
    913. 

  913. #	movq	%r9,%rcx	; if 4th argument ...
    914. 

  914. #	movq	40(%rsp),%r8	; if 5th ...
    915. 

  915. #	movq	48(%rsp),%r9	; if 6th ...
    916. 

  916. # endif
    917. 

  917. #	...
    918. 

  918. # ifdef WIN64
    919. 

  919. #	movq	8(%rsp),%rdi
    920. 

  920. #	movq	16(%rsp),%rsi
    921. 

  921. # endif
    922. 

  922. #	ret
    923. 

  923. #
    924. 

  924. #################################################
    925. 

  925. # Win64 SEH, Structured Exception Handling.
    926. 

  926. #
    927. 

  927. # Unlike on Unix systems(*) lack of Win64 stack unwinding information
    928. 

  928. # has undesired side-effect at run-time: if an exception is raised in
    929. 

  929. # assembler subroutine such as those in question (basically we're
    930. 

  930. # referring to segmentation violations caused by malformed input
    931. 

  931. # parameters), the application is briskly terminated without invoking
    932. 

  932. # any exception handlers, most notably without generating memory dump
    933. 

  933. # or any user notification whatsoever. This poses a problem. It's
    934. 

  934. # possible to address it by registering custom language-specific
    935. 

  935. # handler that would restore processor context to the state at
    936. 

  936. # subroutine entry point and return "exception is not handled, keep
    937. 

  937. # unwinding" code. Writing such handler can be a challenge... But it's
    938. 

  938. # doable, though requires certain coding convention. Consider following
    939. 

  939. # snippet:
    940. 

  940. #
    941. 

  941. # .type	function,@function
    942. 

  942. # function:
    943. 

  943. #	movq	%rsp,%rax	# copy rsp to volatile register
    944. 

  944. #	pushq	%r15		# save non-volatile registers
    945. 

  945. #	pushq	%rbx
    946. 

  946. #	pushq	%rbp
    947. 

  947. #	movq	%rsp,%r11
    948. 

  948. #	subq	%rdi,%r11	# prepare [variable] stack frame
    949. 

  949. #	andq	$-64,%r11
    950. 

  950. #	movq	%rax,0(%r11)	# check for exceptions
    951. 

  951. #	movq	%r11,%rsp	# allocate [variable] stack frame
    952. 

  952. #	movq	%rax,0(%rsp)	# save original rsp value
    953. 

  953. # magic_point:
    954. 

  954. #	...
    955. 

  955. #	movq	0(%rsp),%rcx	# pull original rsp value
    956. 

  956. #	movq	-24(%rcx),%rbp	# restore non-volatile registers
    957. 

  957. #	movq	-16(%rcx),%rbx
    958. 

  958. #	movq	-8(%rcx),%r15
    959. 

  959. #	movq	%rcx,%rsp	# restore original rsp
    960. 

  960. #	ret
    961. 

  961. # .size function,.-function
    962. 

  962. #
    963. 

  963. # The key is that up to magic_point copy of original rsp value remains
    964. 

  964. # in chosen volatile register and no non-volatile register, except for
    965. 

  965. # rsp, is modified. While past magic_point rsp remains constant till
    966. 

  966. # the very end of the function. In this case custom language-specific
    967. 

  967. # exception handler would look like this:
    968. 

  968. #
    969. 

  969. # EXCEPTION_DISPOSITION handler (EXCEPTION_RECORD *rec,ULONG64 frame,
    970. 

  970. #		CONTEXT *context,DISPATCHER_CONTEXT *disp)
    971. 

  971. # {	ULONG64 *rsp = (ULONG64 *)context->Rax;
    972. 

  972. #	if (context->Rip >= magic_point)
    973. 

  973. #	{   rsp = ((ULONG64 **)context->Rsp)[0];
    974. 

  974. #	    context->Rbp = rsp[-3];
    975. 

  975. #	    context->Rbx = rsp[-2];
    976. 

  976. #	    context->R15 = rsp[-1];
    977. 

  977. #	}
    978. 

  978. #	context->Rsp = (ULONG64)rsp;
    979. 

  979. #	context->Rdi = rsp[1];
    980. 

  980. #	context->Rsi = rsp[2];
    981. 

  981. #
    982. 

  982. #	memcpy (disp->ContextRecord,context,sizeof(CONTEXT));
    983. 

  983. #	RtlVirtualUnwind(UNW_FLAG_NHANDLER,disp->ImageBase,
    984. 

  984. #		dips->ControlPc,disp->FunctionEntry,disp->ContextRecord,
    985. 

  985. #		&disp->HandlerData,&disp->EstablisherFrame,NULL);
    986. 

  986. #	return ExceptionContinueSearch;
    987. 

  987. # }
    988. 

  988. #
    989. 

  989. # It's appropriate to implement this handler in assembler, directly in
    990. 

  990. # function's module. In order to do that one has to know members'
    991. 

  991. # offsets in CONTEXT and DISPATCHER_CONTEXT structures and some constant
    992. 

  992. # values. Here they are:
    993. 

  993. #
    994. 

  994. #	CONTEXT.Rax				120
    995. 

  995. #	CONTEXT.Rcx				128
    996. 

  996. #	CONTEXT.Rdx				136
    997. 

  997. #	CONTEXT.Rbx				144
    998. 

  998. #	CONTEXT.Rsp				152
    999. 

  999. #	CONTEXT.Rbp				160
    1000. 

  1000. #	CONTEXT.Rsi				168
    1001. 

  1001. #	CONTEXT.Rdi				176
    1002. 

  1002. #	CONTEXT.R8				184
    1003. 

  1003. #	CONTEXT.R9				192
    1004. 

  1004. #	CONTEXT.R10				200
    1005. 

  1005. #	CONTEXT.R11				208
    1006. 

  1006. #	CONTEXT.R12				216
    1007. 

  1007. #	CONTEXT.R13				224
    1008. 

  1008. #	CONTEXT.R14				232
    1009. 

  1009. #	CONTEXT.R15				240
    1010. 

  1010. #	CONTEXT.Rip				248
    1011. 

  1011. #	CONTEXT.Xmm6				512
    1012. 

  1012. #	sizeof(CONTEXT)				1232
    1013. 

  1013. #	DISPATCHER_CONTEXT.ControlPc		0
    1014. 

  1014. #	DISPATCHER_CONTEXT.ImageBase		8
    1015. 

  1015. #	DISPATCHER_CONTEXT.FunctionEntry	16
    1016. 

  1016. #	DISPATCHER_CONTEXT.EstablisherFrame	24
    1017. 

  1017. #	DISPATCHER_CONTEXT.TargetIp		32
    1018. 

  1018. #	DISPATCHER_CONTEXT.ContextRecord	40
    1019. 

  1019. #	DISPATCHER_CONTEXT.LanguageHandler	48
    1020. 

  1020. #	DISPATCHER_CONTEXT.HandlerData		56
    1021. 

  1021. #	UNW_FLAG_NHANDLER			0
    1022. 

  1022. #	ExceptionContinueSearch			1
    1023. 

  1023. #
    1024. 

  1024. # In order to tie the handler to the function one has to compose
    1025. 

  1025. # couple of structures: one for .xdata segment and one for .pdata.
    1026. 

  1026. #
    1027. 

  1027. # UNWIND_INFO structure for .xdata segment would be
    1028. 

  1028. #
    1029. 

  1029. # function_unwind_info:
    1030. 

  1030. #	.byte	9,0,0,0
    1031. 

  1031. #	.rva	handler
    1032. 

  1032. #
    1033. 

  1033. # This structure designates exception handler for a function with
    1034. 

  1034. # zero-length prologue, no stack frame or frame register.
    1035. 

  1035. #
    1036. 

  1036. # To facilitate composing of .pdata structures, auto-generated "gear"
    1037. 

  1037. # prologue copies rsp value to rax and denotes next instruction with
    1038. 

  1038. # .LSEH_begin_{function_name} label. This essentially defines the SEH
    1039. 

  1039. # styling rule mentioned in the beginning. Position of this label is
    1040. 

  1040. # chosen in such manner that possible exceptions raised in the "gear"
    1041. 

  1041. # prologue would be accounted to caller and unwound from latter's frame.
    1042. 

  1042. # End of function is marked with respective .LSEH_end_{function_name}
    1043. 

  1043. # label. To summarize, .pdata segment would contain
    1044. 

  1044. #
    1045. 

  1045. #	.rva	.LSEH_begin_function
    1046. 

  1046. #	.rva	.LSEH_end_function
    1047. 

  1047. #	.rva	function_unwind_info
    1048. 

  1048. #
    1049. 

  1049. # Reference to functon_unwind_info from .xdata segment is the anchor.
    1050. 

  1050. # In case you wonder why references are 32-bit .rvas and not 64-bit
    1051. 

  1051. # .quads. References put into these two segments are required to be
    1052. 

  1052. # *relative* to the base address of the current binary module, a.k.a.
    1053. 

  1053. # image base. No Win64 module, be it .exe or .dll, can be larger than
    1054. 

  1054. # 2GB and thus such relative references can be and are accommodated in
    1055. 

  1055. # 32 bits.
    1056. 

  1056. #
    1057. 

  1057. # Having reviewed the example function code, one can argue that "movq
    1058. 

  1058. # %rsp,%rax" above is redundant. It is not! Keep in mind that on Unix
    1059. 

  1059. # rax would contain an undefined value. If this "offends" you, use
    1060. 

  1060. # another register and refrain from modifying rax till magic_point is
    1061. 

  1061. # reached, i.e. as if it was a non-volatile register. If more registers
    1062. 

  1062. # are required prior [variable] frame setup is completed, note that
    1063. 

  1063. # nobody says that you can have only one "magic point." You can
    1064. 

  1064. # "liberate" non-volatile registers by denoting last stack off-load
    1065. 

  1065. # instruction and reflecting it in finer grade unwind logic in handler.
    1066. 

  1066. # After all, isn't it why it's called *language-specific* handler...
    1067. 

  1067. #
    1068. 

  1068. # Attentive reader can notice that exceptions would be mishandled in
    1069. 

  1069. # auto-generated "gear" epilogue. Well, exception effectively can't
    1070. 

  1070. # occur there, because if memory area used by it was subject to
    1071. 

  1071. # segmentation violation, then it would be raised upon call to the
    1072. 

  1072. # function (and as already mentioned be accounted to caller, which is
    1073. 

  1073. # not a problem). If you're still not comfortable, then define tail
    1074. 

  1074. # "magic point" just prior ret instruction and have handler treat it...
    1075. 

  1075. #
    1076. 

  1076. # (*)	Note that we're talking about run-time, not debug-time. Lack of
    1077. 

  1077. #	unwind information makes debugging hard on both Windows and
    1078. 

  1078. #	Unix. "Unlike" referes to the fact that on Unix signal handler
    1079. 

  1079. #	will always be invoked, core dumped and appropriate exit code
    1080. 

  1080. #	returned to parent (for user notification).
    1081. 

  1081.