2 # Copyright 2005-2016 The OpenSSL Project Authors. All Rights Reserved.
4 # Licensed under the OpenSSL license (the "License"). You may not use
5 # this file except in compliance with the License. You can obtain a copy
6 # in the file LICENSE in the source distribution or at
7 # https://www.openssl.org/source/license.html
10 # Ascetic x86_64 AT&T to MASM/NASM assembler translator by <appro>.
12 # Why AT&T to MASM and not vice versa? Several reasons. Because AT&T
13 # format is way easier to parse. Because it's simpler to "gear" from
14 # Unix ABI to Windows one [see cross-reference "card" at the end of
15 # file]. Because Linux targets were available first...
17 # In addition the script also "distills" code suitable for GNU
18 # assembler, so that it can be compiled with more rigid assemblers,
19 # such as Solaris /usr/ccs/bin/as.
21 # This translator is not designed to convert *arbitrary* assembler
22 # code from AT&T format to MASM one. It's designed to convert just
23 # enough to provide for dual-ABI OpenSSL modules development...
24 # There *are* limitations and you might have to modify your assembler
25 # code or this script to achieve the desired result...
27 # Currently recognized limitations:
29 # - can't use multiple ops per line;
31 # Dual-ABI styling rules.
33 # 1. Adhere to Unix register and stack layout [see cross-reference
34 # ABI "card" at the end for explanation].
35 # 2. Forget about "red zone," stick to more traditional blended
36 # stack frame allocation. If volatile storage is actually required
37 # that is. If not, just leave the stack as is.
38 # 3. Functions tagged with ".type name,@function" get crafted with
39 # unified Win64 prologue and epilogue automatically. If you want
40 # to take care of ABI differences yourself, tag functions as
41 # ".type name,@abi-omnipotent" instead.
42 # 4. To optimize the Win64 prologue you can specify number of input
43 # arguments as ".type name,@function,N." Keep in mind that if N is
44 # larger than 6, then you *have to* write "abi-omnipotent" code,
45 # because >6 cases can't be addressed with unified prologue.
46 # 5. Name local labels as .L*, do *not* use dynamic labels such as 1:
47 # (sorry about latter).
48 # 6. Don't use [or hand-code with .byte] "rep ret." "ret" mnemonic is
49 # required to identify the spots, where to inject Win64 epilogue!
50 # But on the pros, it's then prefixed with rep automatically:-)
51 # 7. Stick to explicit ip-relative addressing. If you have to use
52 # GOTPCREL addressing, stick to mov symbol@GOTPCREL(%rip),%r??.
53 # Both are recognized and translated to proper Win64 addressing
54 # modes. To support legacy code a synthetic directive, .picmeup,
55 # is implemented. It puts address of the *next* instruction into
56 # target register, e.g.:
59 # lea .Label-.(%rax),%rax
61 # 8. In order to provide for structured exception handling unified
62 # Win64 prologue copies %rsp value to %rax. For further details
63 # see SEH paragraph at the end.
64 # 9. .init segment is allowed to contain calls to functions only.
65 # a. If function accepts more than 4 arguments *and* >4th argument
66 # is declared as non 64-bit value, do clear its upper part.
73 if ($flavour =~ /\./) { $output = $flavour; undef $flavour; }
75 open STDOUT,">$output" || die "can't open $output: $!"
76 if (defined($output));
78 my $gas=1; $gas=0 if ($output =~ /\.asm$/);
79 my $elf=1; $elf=0 if (!$gas);
84 my $masmref=8 + 50727*2**-32; # 8.00.50727 shipped with VS2005
91 if ($flavour eq "mingw64") { $gas=1; $elf=0; $win64=1;
92 $prefix=`echo __USER_LABEL_PREFIX__ | $ENV{CC} -E -P -`;
93 $prefix =~ s|\R$||; # Better chomp
95 elsif ($flavour eq "macosx") { $gas=1; $elf=0; $prefix="_"; $decor="L\$"; }
96 elsif ($flavour eq "masm") { $gas=0; $elf=0; $masm=$masmref; $win64=1; $decor="\$L\$"; }
97 elsif ($flavour eq "nasm") { $gas=0; $elf=0; $nasm=$nasmref; $win64=1; $decor="\$L\$"; $PTR=""; }
99 { if ($ENV{ASM} =~ m/nasm/ && `nasm -v` =~ m/version ([0-9]+)\.([0-9]+)/i)
100 { $nasm = $1 + $2*0.01; $PTR=""; }
101 elsif (`ml64 2>&1` =~ m/Version ([0-9]+)\.([0-9]+)(\.([0-9]+))?/)
102 { $masm = $1 + $2*2**-16 + $4*2**-32; }
103 die "no assembler found on %PATH" if (!($nasm || $masm));
110 my $current_function;
113 { package opcode; # pick up opcodes
115 my ($class, $line) = @_;
119 if ($$line =~ /^([a-z][a-z0-9]*)/i) {
123 $$line = substr($$line,@+[0]); $$line =~ s/^\s+//;
126 if ($self->{op} =~ /^(movz)x?([bw]).*/) { # movz is pain...
129 } elsif ($self->{op} =~ /call|jmp/) {
131 } elsif ($self->{op} =~ /^p/ && $' !~ /^(ush|op|insrw)/) { # SSEn
133 } elsif ($self->{op} =~ /^v/) { # VEX
135 } elsif ($self->{op} =~ /mov[dq]/ && $$line =~ /%xmm/) {
137 } elsif ($self->{op} =~ /([a-z]{3,})([qlwb])$/) {
145 my ($self, $sz) = @_;
146 $self->{sz} = $sz if (defined($sz) && !defined($self->{sz}));
152 if ($self->{op} eq "movz") { # movz is pain...
153 sprintf "%s%s%s",$self->{op},$self->{sz},shift;
154 } elsif ($self->{op} =~ /^set/) {
156 } elsif ($self->{op} eq "ret") {
158 if ($win64 && $current_function->{abi} eq "svr4") {
159 $epilogue = "movq 8(%rsp),%rdi\n\t" .
160 "movq 16(%rsp),%rsi\n\t";
162 $epilogue . ".byte 0xf3,0xc3";
163 } elsif ($self->{op} eq "call" && !$elf && $current_segment eq ".init") {
164 ".p2align\t3\n\t.quad";
166 "$self->{op}$self->{sz}";
169 $self->{op} =~ s/^movz/movzx/;
170 if ($self->{op} eq "ret") {
172 if ($win64 && $current_function->{abi} eq "svr4") {
173 $self->{op} = "mov rdi,QWORD${PTR}[8+rsp]\t;WIN64 epilogue\n\t".
174 "mov rsi,QWORD${PTR}[16+rsp]\n\t";
176 $self->{op} .= "DB\t0F3h,0C3h\t\t;repret";
177 } elsif ($self->{op} =~ /^(pop|push)f/) {
178 $self->{op} .= $self->{sz};
179 } elsif ($self->{op} eq "call" && $current_segment eq ".CRT\$XCU") {
180 $self->{op} = "\tDQ";
186 my ($self, $op) = @_;
187 $self->{op}=$op if (defined($op));
191 { package const; # pick up constants, which start with $
193 my ($class, $line) = @_;
197 if ($$line =~ /^\$([^,]+)/) {
201 $$line = substr($$line,@+[0]); $$line =~ s/^\s+//;
208 $self->{value} =~ s/\b(0b[0-1]+)/oct($1)/eig;
210 # Solaris /usr/ccs/bin/as can't handle multiplications
212 my $value = $self->{value};
213 $value =~ s/(?<![\w\$\.])(0x?[0-9a-f]+)/oct($1)/egi;
214 if ($value =~ s/([0-9]+\s*[\*\/\%]\s*[0-9]+)/eval($1)/eg) {
215 $self->{value} = $value;
217 sprintf "\$%s",$self->{value};
219 $self->{value} =~ s/0x([0-9a-f]+)/0$1h/ig if ($masm);
220 sprintf "%s",$self->{value};
224 { package ea; # pick up effective addresses: expr(%reg,%reg,scale)
226 my ($class, $line, $opcode) = @_;
230 # optional * ---vvv--- appears in indirect jmp/call
231 if ($$line =~ /^(\*?)([^\(,]*)\(([%\w,]+)\)/) {
233 $self->{asterisk} = $1;
235 ($self->{base},$self->{index},$self->{scale})=split(/,/,$3);
236 $self->{scale} = 1 if (!defined($self->{scale}));
238 $$line = substr($$line,@+[0]); $$line =~ s/^\s+//;
240 if ($win64 && $self->{label} =~ s/\@GOTPCREL//) {
241 die if ($opcode->mnemonic() ne "mov");
242 $opcode->mnemonic("lea");
244 $self->{base} =~ s/^%//;
245 $self->{index} =~ s/^%// if (defined($self->{index}));
246 $self->{opcode} = $opcode;
252 my ($self, $sz) = @_;
254 $self->{label} =~ s/([_a-z][_a-z0-9]*)/$globals{$1} or $1/gei;
255 $self->{label} =~ s/\.L/$decor/g;
257 # Silently convert all EAs to 64-bit. This is required for
258 # elder GNU assembler and results in more compact code,
259 # *but* most importantly AES module depends on this feature!
260 $self->{index} =~ s/^[er](.?[0-9xpi])[d]?$/r\1/;
261 $self->{base} =~ s/^[er](.?[0-9xpi])[d]?$/r\1/;
263 # Solaris /usr/ccs/bin/as can't handle multiplications
264 # in $self->{label}, new gas requires sign extension...
266 $self->{label} =~ s/(?<![\w\$\.])(0x?[0-9a-f]+)/oct($1)/egi;
267 $self->{label} =~ s/\b([0-9]+\s*[\*\/\%]\s*[0-9]+)\b/eval($1)/eg;
268 $self->{label} =~ s/\b([0-9]+)\b/$1<<32>>32/eg;
270 if (!$self->{label} && $self->{index} && $self->{scale}==1 &&
271 $self->{base} =~ /(rbp|r13)/) {
272 $self->{base} = $self->{index}; $self->{index} = $1;
276 $self->{label} =~ s/^___imp_/__imp__/ if ($flavour eq "mingw64");
278 if (defined($self->{index})) {
279 sprintf "%s%s(%s,%%%s,%d)",$self->{asterisk},
281 $self->{base}?"%$self->{base}":"",
282 $self->{index},$self->{scale};
284 sprintf "%s%s(%%%s)", $self->{asterisk},$self->{label},$self->{base};
287 my %szmap = ( b=>"BYTE$PTR", w=>"WORD$PTR",
288 l=>"DWORD$PTR", d=>"DWORD$PTR",
289 q=>"QWORD$PTR", o=>"OWORD$PTR",
290 x=>"XMMWORD$PTR", y=>"YMMWORD$PTR", z=>"ZMMWORD$PTR" );
292 $self->{label} =~ s/\./\$/g;
293 $self->{label} =~ s/(?<![\w\$\.])0x([0-9a-f]+)/0$1h/ig;
294 $self->{label} = "($self->{label})" if ($self->{label} =~ /[\*\+\-\/]/);
296 my $mnemonic = $self->{opcode}->mnemonic();
297 ($self->{asterisk}) && ($sz="q") ||
298 ($mnemonic =~ /^v?mov([qd])$/) && ($sz=$1) ||
299 ($mnemonic =~ /^v?pinsr([qdwb])$/) && ($sz=$1) ||
300 ($mnemonic =~ /^vpbroadcast([qdwb])$/) && ($sz=$1) ||
301 ($mnemonic =~ /^v(?!perm)[a-z]+[fi]128$/) && ($sz="x");
303 if (defined($self->{index})) {
304 sprintf "%s[%s%s*%d%s]",$szmap{$sz},
305 $self->{label}?"$self->{label}+":"",
306 $self->{index},$self->{scale},
307 $self->{base}?"+$self->{base}":"";
308 } elsif ($self->{base} eq "rip") {
309 sprintf "%s[%s]",$szmap{$sz},$self->{label};
311 sprintf "%s[%s%s]",$szmap{$sz},
312 $self->{label}?"$self->{label}+":"",
318 { package register; # pick up registers, which start with %.
320 my ($class, $line) = @_;
324 # optional * ---vvv--- appears in indirect jmp/call
325 if ($$line =~ /^(\*?)%(\w+)/) {
327 $self->{asterisk} = $1;
330 $$line = substr($$line,@+[0]); $$line =~ s/^\s+//;
338 if ($self->{value} =~ /^r[\d]+b$/i) { $ret="b"; }
339 elsif ($self->{value} =~ /^r[\d]+w$/i) { $ret="w"; }
340 elsif ($self->{value} =~ /^r[\d]+d$/i) { $ret="l"; }
341 elsif ($self->{value} =~ /^r[\w]+$/i) { $ret="q"; }
342 elsif ($self->{value} =~ /^[a-d][hl]$/i){ $ret="b"; }
343 elsif ($self->{value} =~ /^[\w]{2}l$/i) { $ret="b"; }
344 elsif ($self->{value} =~ /^[\w]{2}$/i) { $ret="w"; }
345 elsif ($self->{value} =~ /^e[a-z]{2}$/i){ $ret="l"; }
351 if ($gas) { sprintf "%s%%%s",$self->{asterisk},$self->{value}; }
352 else { $self->{value}; }
355 { package label; # pick up labels, which end with :
357 my ($class, $line) = @_;
361 if ($$line =~ /(^[\.\w]+)\:/) {
365 $$line = substr($$line,@+[0]); $$line =~ s/^\s+//;
367 $self->{value} =~ s/^\.L/$decor/;
375 my $func = ($globals{$self->{value}} or $self->{value}) . ":";
377 $current_function->{name} eq $self->{value} &&
378 $current_function->{abi} eq "svr4") {
380 $func .= " movq %rdi,8(%rsp)\n";
381 $func .= " movq %rsi,16(%rsp)\n";
382 $func .= " movq %rsp,%rax\n";
383 $func .= "${decor}SEH_begin_$current_function->{name}:\n";
384 my $narg = $current_function->{narg};
385 $narg=6 if (!defined($narg));
386 $func .= " movq %rcx,%rdi\n" if ($narg>0);
387 $func .= " movq %rdx,%rsi\n" if ($narg>1);
388 $func .= " movq %r8,%rdx\n" if ($narg>2);
389 $func .= " movq %r9,%rcx\n" if ($narg>3);
390 $func .= " movq 40(%rsp),%r8\n" if ($narg>4);
391 $func .= " movq 48(%rsp),%r9\n" if ($narg>5);
394 } elsif ($self->{value} ne "$current_function->{name}") {
395 # Make all labels in masm global.
396 $self->{value} .= ":" if ($masm);
397 $self->{value} . ":";
398 } elsif ($win64 && $current_function->{abi} eq "svr4") {
399 my $func = "$current_function->{name}" .
400 ($nasm ? ":" : "\tPROC $current_function->{scope}") .
402 $func .= " mov QWORD${PTR}[8+rsp],rdi\t;WIN64 prologue\n";
403 $func .= " mov QWORD${PTR}[16+rsp],rsi\n";
404 $func .= " mov rax,rsp\n";
405 $func .= "${decor}SEH_begin_$current_function->{name}:";
406 $func .= ":" if ($masm);
408 my $narg = $current_function->{narg};
409 $narg=6 if (!defined($narg));
410 $func .= " mov rdi,rcx\n" if ($narg>0);
411 $func .= " mov rsi,rdx\n" if ($narg>1);
412 $func .= " mov rdx,r8\n" if ($narg>2);
413 $func .= " mov rcx,r9\n" if ($narg>3);
414 $func .= " mov r8,QWORD${PTR}[40+rsp]\n" if ($narg>4);
415 $func .= " mov r9,QWORD${PTR}[48+rsp]\n" if ($narg>5);
418 "$current_function->{name}".
419 ($nasm ? ":" : "\tPROC $current_function->{scope}");
423 { package expr; # pick up expressioins
425 my ($class, $line, $opcode) = @_;
429 if ($$line =~ /(^[^,]+)/) {
433 $$line = substr($$line,@+[0]); $$line =~ s/^\s+//;
435 $self->{value} =~ s/\@PLT// if (!$elf);
436 $self->{value} =~ s/([_a-z][_a-z0-9]*)/$globals{$1} or $1/gei;
437 $self->{value} =~ s/\.L/$decor/g;
438 $self->{opcode} = $opcode;
444 if ($nasm && $self->{opcode}->mnemonic()=~m/^j(?![re]cxz)/) {
445 "NEAR ".$self->{value};
451 { package directive; # pick up directives, which start with .
453 my ($class, $line) = @_;
457 my %opcode = # lea 2f-1f(%rip),%dst; 1: nop; 2:
458 ( "%rax"=>0x01058d48, "%rcx"=>0x010d8d48,
459 "%rdx"=>0x01158d48, "%rbx"=>0x011d8d48,
460 "%rsp"=>0x01258d48, "%rbp"=>0x012d8d48,
461 "%rsi"=>0x01358d48, "%rdi"=>0x013d8d48,
462 "%r8" =>0x01058d4c, "%r9" =>0x010d8d4c,
463 "%r10"=>0x01158d4c, "%r11"=>0x011d8d4c,
464 "%r12"=>0x01258d4c, "%r13"=>0x012d8d4c,
465 "%r14"=>0x01358d4c, "%r15"=>0x013d8d4c );
467 if ($$line =~ /^\s*(\.\w+)/) {
471 undef $self->{value};
472 $$line = substr($$line,@+[0]); $$line =~ s/^\s+//;
475 /\.picmeup/ && do { if ($$line =~ /(%r[\w]+)/i) {
477 $$line=sprintf "0x%x,0x90000000",$opcode{$1};
481 /\.global|\.globl|\.extern/
482 && do { $globals{$$line} = $prefix . $$line;
483 $$line = $globals{$$line} if ($prefix);
486 /\.type/ && do { my ($sym,$type,$narg) = split(',',$$line);
487 if ($type eq "\@function") {
488 undef $current_function;
489 $current_function->{name} = $sym;
490 $current_function->{abi} = "svr4";
491 $current_function->{narg} = $narg;
492 $current_function->{scope} = defined($globals{$sym})?"PUBLIC":"PRIVATE";
493 } elsif ($type eq "\@abi-omnipotent") {
494 undef $current_function;
495 $current_function->{name} = $sym;
496 $current_function->{scope} = defined($globals{$sym})?"PUBLIC":"PRIVATE";
498 $$line =~ s/\@abi\-omnipotent/\@function/;
499 $$line =~ s/\@function.*/\@function/;
502 /\.asciz/ && do { if ($$line =~ /^"(.*)"$/) {
504 $$line = join(",",unpack("C*",$1),0);
508 /\.rva|\.long|\.quad/
509 && do { $$line =~ s/([_a-z][_a-z0-9]*)/$globals{$1} or $1/gei;
510 $$line =~ s/\.L/$decor/g;
516 $self->{value} = $dir . "\t" . $$line;
518 if ($dir =~ /\.extern/) {
519 $self->{value} = ""; # swallow extern
520 } elsif (!$elf && $dir =~ /\.type/) {
522 $self->{value} = ".def\t" . ($globals{$1} or $1) . ";\t" .
523 (defined($globals{$1})?".scl 2;":".scl 3;") .
524 "\t.type 32;\t.endef"
525 if ($win64 && $$line =~ /([^,]+),\@function/);
526 } elsif (!$elf && $dir =~ /\.size/) {
528 if (defined($current_function)) {
529 $self->{value} .= "${decor}SEH_end_$current_function->{name}:"
530 if ($win64 && $current_function->{abi} eq "svr4");
531 undef $current_function;
533 } elsif (!$elf && $dir =~ /\.align/) {
534 $self->{value} = ".p2align\t" . (log($$line)/log(2));
535 } elsif ($dir eq ".section") {
536 $current_segment=$$line;
537 if (!$elf && $current_segment eq ".init") {
538 if ($flavour eq "macosx") { $self->{value} = ".mod_init_func"; }
539 elsif ($flavour eq "mingw64") { $self->{value} = ".section\t.ctors"; }
541 } elsif ($dir =~ /\.(text|data)/) {
542 $current_segment=".$1";
543 } elsif ($dir =~ /\.hidden/) {
544 if ($flavour eq "macosx") { $self->{value} = ".private_extern\t$prefix$$line"; }
545 elsif ($flavour eq "mingw64") { $self->{value} = ""; }
546 } elsif ($dir =~ /\.comm/) {
547 $self->{value} = "$dir\t$prefix$$line";
548 $self->{value} =~ s|,([0-9]+),([0-9]+)$|",$1,".log($2)/log(2)|e if ($flavour eq "macosx");
554 # non-gas case or nasm/masm
556 /\.text/ && do { my $v=undef;
558 $v="section .text code align=64\n";
560 $v="$current_segment\tENDS\n" if ($current_segment);
561 $current_segment = ".text\$";
562 $v.="$current_segment\tSEGMENT ";
563 $v.=$masm>=$masmref ? "ALIGN(256)" : "PAGE";
569 /\.data/ && do { my $v=undef;
571 $v="section .data data align=8\n";
573 $v="$current_segment\tENDS\n" if ($current_segment);
574 $current_segment = "_DATA";
575 $v.="$current_segment\tSEGMENT";
580 /\.section/ && do { my $v=undef;
581 $$line =~ s/([^,]*).*/$1/;
582 $$line = ".CRT\$XCU" if ($$line eq ".init");
585 if ($$line=~/\.([px])data/) {
587 $v.=$1 eq "p"? 4 : 8;
588 } elsif ($$line=~/\.CRT\$/i) {
589 $v.=" rdata align=8";
592 $v="$current_segment\tENDS\n" if ($current_segment);
593 $v.="$$line\tSEGMENT";
594 if ($$line=~/\.([px])data/) {
596 $v.=" ALIGN(".($1 eq "p" ? 4 : 8).")" if ($masm>=$masmref);
597 } elsif ($$line=~/\.CRT\$/i) {
599 $v.=$masm>=$masmref ? "ALIGN(8)" : "DWORD";
602 $current_segment = $$line;
606 /\.extern/ && do { $self->{value} = "EXTERN\t".$$line;
607 $self->{value} .= ":NEAR" if ($masm);
611 && do { $self->{value} = $masm?"PUBLIC":"global";
612 $self->{value} .= "\t".$$line;
615 /\.size/ && do { if (defined($current_function)) {
616 undef $self->{value};
617 if ($current_function->{abi} eq "svr4") {
618 $self->{value}="${decor}SEH_end_$current_function->{name}:";
619 $self->{value}.=":\n" if($masm);
621 $self->{value}.="$current_function->{name}\tENDP" if($masm && $current_function->{name});
622 undef $current_function;
626 /\.align/ && do { my $max = ($masm && $masm>=$masmref) ? 256 : 4096;
627 $self->{value} = "ALIGN\t".($$line>$max?$max:$$line);
630 /\.(value|long|rva|quad)/
631 && do { my $sz = substr($1,0,1);
632 my @arr = split(/,\s*/,$$line);
633 my $last = pop(@arr);
634 my $conv = sub { my $var=shift;
635 $var=~s/^(0b[0-1]+)/oct($1)/eig;
636 $var=~s/^0x([0-9a-f]+)/0$1h/ig if ($masm);
637 if ($sz eq "D" && ($current_segment=~/.[px]data/ || $dir eq ".rva"))
638 { $var=~s/([_a-z\$\@][_a-z0-9\$\@]*)/$nasm?"$1 wrt ..imagebase":"imagerel $1"/egi; }
642 $sz =~ tr/bvlrq/BWDDQ/;
643 $self->{value} = "\tD$sz\t";
644 for (@arr) { $self->{value} .= &$conv($_).","; }
645 $self->{value} .= &$conv($last);
648 /\.byte/ && do { my @str=split(/,\s*/,$$line);
649 map(s/(0b[0-1]+)/oct($1)/eig,@str);
650 map(s/0x([0-9a-f]+)/0$1h/ig,@str) if ($masm);
652 $self->{value}.="DB\t"
653 .join(",",@str[0..15])."\n";
654 foreach (0..15) { shift @str; }
656 $self->{value}.="DB\t"
657 .join(",",@str) if (@str);
660 /\.comm/ && do { my @str=split(/,\s*/,$$line);
663 $v.="common $prefix@str[0] @str[1]";
665 $v="$current_segment\tENDS\n" if ($current_segment);
666 $current_segment = "_DATA";
667 $v.="$current_segment\tSEGMENT\n";
668 $v.="COMM @str[0]:DWORD:".@str[1]/4;
687 my ($dst,$src,$rex)=@_;
689 $rex|=0x04 if($dst>=8);
690 $rex|=0x01 if($src>=8);
691 push @$opcode,($rex|0x40) if ($rex);
694 # older gas and ml64 don't handle SSE>2 instructions
695 my %regrm = ( "%eax"=>0, "%ecx"=>1, "%edx"=>2, "%ebx"=>3,
696 "%esp"=>4, "%ebp"=>5, "%esi"=>6, "%edi"=>7 );
698 my $movq = sub { # elderly gas can't handle inter-register movq
701 if ($arg =~ /%xmm([0-9]+),\s*%r(\w+)/) {
702 my ($src,$dst)=($1,$2);
703 if ($dst !~ /[0-9]+/) { $dst = $regrm{"%e$dst"}; }
704 rex(\@opcode,$src,$dst,0x8);
705 push @opcode,0x0f,0x7e;
706 push @opcode,0xc0|(($src&7)<<3)|($dst&7); # ModR/M
708 } elsif ($arg =~ /%r(\w+),\s*%xmm([0-9]+)/) {
709 my ($src,$dst)=($2,$1);
710 if ($dst !~ /[0-9]+/) { $dst = $regrm{"%e$dst"}; }
711 rex(\@opcode,$src,$dst,0x8);
712 push @opcode,0x0f,0x6e;
713 push @opcode,0xc0|(($src&7)<<3)|($dst&7); # ModR/M
721 if (shift =~ /\$([0-9]+),\s*%xmm([0-9]+),\s*(%\w+)/) {
726 if ($dst =~ /%r([0-9]+)d/) { $dst = $1; }
727 elsif ($dst =~ /%e/) { $dst = $regrm{$dst}; }
728 rex(\@opcode,$src,$dst);
729 push @opcode,0x0f,0x3a,0x16;
730 push @opcode,0xc0|(($src&7)<<3)|($dst&7); # ModR/M
739 if (shift =~ /\$([0-9]+),\s*(%\w+),\s*%xmm([0-9]+)/) {
744 if ($src =~ /%r([0-9]+)/) { $src = $1; }
745 elsif ($src =~ /%e/) { $src = $regrm{$src}; }
746 rex(\@opcode,$dst,$src);
747 push @opcode,0x0f,0x3a,0x22;
748 push @opcode,0xc0|(($dst&7)<<3)|($src&7); # ModR/M
757 if (shift =~ /%xmm([0-9]+),\s*%xmm([0-9]+)/) {
760 push @opcode,0x0f,0x38,0x00;
761 push @opcode,0xc0|($1&7)|(($2&7)<<3); # ModR/M
769 if (shift =~ /\$([0-9]+),\s*%xmm([0-9]+),\s*%xmm([0-9]+)/) {
772 push @opcode,0x0f,0x3a,0x0f;
773 push @opcode,0xc0|($2&7)|(($3&7)<<3); # ModR/M
781 my $pclmulqdq = sub {
782 if (shift =~ /\$([x0-9a-f]+),\s*%xmm([0-9]+),\s*%xmm([0-9]+)/) {
785 push @opcode,0x0f,0x3a,0x44;
786 push @opcode,0xc0|($2&7)|(($3&7)<<3); # ModR/M
788 push @opcode,$c=~/^0/?oct($c):$c;
796 if (shift =~ /%[er](\w+)/) {
799 if ($dst !~ /[0-9]+/) { $dst = $regrm{"%e$dst"}; }
800 rex(\@opcode,0,$1,8);
801 push @opcode,0x0f,0xc7,0xf0|($dst&7);
809 if (shift =~ /%[er](\w+)/) {
812 if ($dst !~ /[0-9]+/) { $dst = $regrm{"%e$dst"}; }
813 rex(\@opcode,0,$1,8);
814 push @opcode,0x0f,0xc7,0xf8|($dst&7);
823 my ($dst,$src1,$src2,$rxb)=@_;
826 $rxb&=~(0x04<<5) if($dst>=8);
827 $rxb&=~(0x01<<5) if($src1>=8);
828 $rxb&=~(0x02<<5) if($src2>=8);
833 if (shift =~ /\$([x0-9a-f]+),\s*%xmm([0-9]+),\s*%xmm([0-9]+)/) {
835 rxb(\@opcode,$3,$2,-1,0x08);
836 push @opcode,0x78,0xc2;
837 push @opcode,0xc0|($2&7)|(($3&7)<<3); # ModR/M
839 push @opcode,$c=~/^0/?oct($c):$c;
847 if (shift =~ /\$([x0-9a-f]+),\s*%xmm([0-9]+),\s*%xmm([0-9]+)/) {
849 rxb(\@opcode,$3,$2,-1,0x08);
850 push @opcode,0x78,0xc3;
851 push @opcode,0xc0|($2&7)|(($3&7)<<3); # ModR/M
853 push @opcode,$c=~/^0/?oct($c):$c;
872 while(defined(my $line=<>)) {
874 $line =~ s|\R$||; # Better chomp
876 $line =~ s|[#!].*$||; # get rid of asm-style comments...
877 $line =~ s|/\*.*\*/||; # ... and C-style comments...
878 $line =~ s|^\s+||; # ... and skip white spaces in beginning
879 $line =~ s|\s+$||; # ... and at the end
881 if (my $label=label->re(\$line)) { print $label->out(); }
883 if (my $directive=directive->re(\$line)) {
884 printf "%s",$directive->out();
885 } elsif (my $opcode=opcode->re(\$line)) {
886 my $asm = eval("\$".$opcode->mnemonic());
888 if ((ref($asm) eq 'CODE') && scalar(my @bytes=&$asm($line))) {
889 print $gas?".byte\t":"DB\t",join(',',@bytes),"\n";
894 ARGUMENT: while (1) {
897 if ($arg=register->re(\$line)) { $opcode->size($arg->size()); }
898 elsif ($arg=const->re(\$line)) { }
899 elsif ($arg=ea->re(\$line, $opcode)) { }
900 elsif ($arg=expr->re(\$line, $opcode)) { }
901 else { last ARGUMENT; }
905 last ARGUMENT if ($line !~ /^,/);
912 my $sz=$opcode->size();
915 $insn = $opcode->out($#args>=1?$args[$#args]->size():$sz);
916 @args = map($_->out($sz),@args);
917 printf "\t%s\t%s",$insn,join(",",@args);
919 $insn = $opcode->out();
922 # $insn.=$sz compensates for movq, pinsrw, ...
923 if ($arg =~ /^xmm[0-9]+$/) { $insn.=$sz; $sz="x" if(!$sz); last; }
924 if ($arg =~ /^ymm[0-9]+$/) { $insn.=$sz; $sz="y" if(!$sz); last; }
925 if ($arg =~ /^zmm[0-9]+$/) { $insn.=$sz; $sz="z" if(!$sz); last; }
926 if ($arg =~ /^mm[0-9]+$/) { $insn.=$sz; $sz="q" if(!$sz); last; }
928 @args = reverse(@args);
929 undef $sz if ($nasm && $opcode->mnemonic() eq "lea");
930 printf "\t%s\t%s",$insn,join(",",map($_->out($sz),@args));
933 printf "\t%s",$opcode->out();
940 print "\n$current_segment\tENDS\n" if ($current_segment && $masm);
941 print "END\n" if ($masm);
945 \f#################################################
946 # Cross-reference x86_64 ABI "card"
966 # (*) volatile register
967 # (-) preserved by callee
968 # (#) Nth argument, volatile
970 # In Unix terms top of stack is argument transfer area for arguments
971 # which could not be accommodated in registers. Or in other words 7th
972 # [integer] argument resides at 8(%rsp) upon function entry point.
973 # 128 bytes above %rsp constitute a "red zone" which is not touched
974 # by signal handlers and can be used as temporal storage without
975 # allocating a frame.
977 # In Win64 terms N*8 bytes on top of stack is argument transfer area,
978 # which belongs to/can be overwritten by callee. N is the number of
979 # arguments passed to callee, *but* not less than 4! This means that
980 # upon function entry point 5th argument resides at 40(%rsp), as well
981 # as that 32 bytes from 8(%rsp) can always be used as temporal
982 # storage [without allocating a frame]. One can actually argue that
983 # one can assume a "red zone" above stack pointer under Win64 as well.
984 # Point is that at apparently no occasion Windows kernel would alter
985 # the area above user stack pointer in true asynchronous manner...
987 # All the above means that if assembler programmer adheres to Unix
988 # register and stack layout, but disregards the "red zone" existense,
989 # it's possible to use following prologue and epilogue to "gear" from
990 # Unix to Win64 ABI in leaf functions with not more than 6 arguments.
992 # omnipotent_function:
996 # movq %rcx,%rdi ; if 1st argument is actually present
997 # movq %rdx,%rsi ; if 2nd argument is actually ...
998 # movq %r8,%rdx ; if 3rd argument is ...
999 # movq %r9,%rcx ; if 4th argument ...
1000 # movq 40(%rsp),%r8 ; if 5th ...
1001 # movq 48(%rsp),%r9 ; if 6th ...
1006 # movq 16(%rsp),%rsi
1010 \f#################################################
1011 # Win64 SEH, Structured Exception Handling.
1013 # Unlike on Unix systems(*) lack of Win64 stack unwinding information
1014 # has undesired side-effect at run-time: if an exception is raised in
1015 # assembler subroutine such as those in question (basically we're
1016 # referring to segmentation violations caused by malformed input
1017 # parameters), the application is briskly terminated without invoking
1018 # any exception handlers, most notably without generating memory dump
1019 # or any user notification whatsoever. This poses a problem. It's
1020 # possible to address it by registering custom language-specific
1021 # handler that would restore processor context to the state at
1022 # subroutine entry point and return "exception is not handled, keep
1023 # unwinding" code. Writing such handler can be a challenge... But it's
1024 # doable, though requires certain coding convention. Consider following
1027 # .type function,@function
1029 # movq %rsp,%rax # copy rsp to volatile register
1030 # pushq %r15 # save non-volatile registers
1034 # subq %rdi,%r11 # prepare [variable] stack frame
1036 # movq %rax,0(%r11) # check for exceptions
1037 # movq %r11,%rsp # allocate [variable] stack frame
1038 # movq %rax,0(%rsp) # save original rsp value
1041 # movq 0(%rsp),%rcx # pull original rsp value
1042 # movq -24(%rcx),%rbp # restore non-volatile registers
1043 # movq -16(%rcx),%rbx
1044 # movq -8(%rcx),%r15
1045 # movq %rcx,%rsp # restore original rsp
1047 # .size function,.-function
1049 # The key is that up to magic_point copy of original rsp value remains
1050 # in chosen volatile register and no non-volatile register, except for
1051 # rsp, is modified. While past magic_point rsp remains constant till
1052 # the very end of the function. In this case custom language-specific
1053 # exception handler would look like this:
1055 # EXCEPTION_DISPOSITION handler (EXCEPTION_RECORD *rec,ULONG64 frame,
1056 # CONTEXT *context,DISPATCHER_CONTEXT *disp)
1057 # { ULONG64 *rsp = (ULONG64 *)context->Rax;
1058 # if (context->Rip >= magic_point)
1059 # { rsp = ((ULONG64 **)context->Rsp)[0];
1060 # context->Rbp = rsp[-3];
1061 # context->Rbx = rsp[-2];
1062 # context->R15 = rsp[-1];
1064 # context->Rsp = (ULONG64)rsp;
1065 # context->Rdi = rsp[1];
1066 # context->Rsi = rsp[2];
1068 # memcpy (disp->ContextRecord,context,sizeof(CONTEXT));
1069 # RtlVirtualUnwind(UNW_FLAG_NHANDLER,disp->ImageBase,
1070 # dips->ControlPc,disp->FunctionEntry,disp->ContextRecord,
1071 # &disp->HandlerData,&disp->EstablisherFrame,NULL);
1072 # return ExceptionContinueSearch;
1075 # It's appropriate to implement this handler in assembler, directly in
1076 # function's module. In order to do that one has to know members'
1077 # offsets in CONTEXT and DISPATCHER_CONTEXT structures and some constant
1078 # values. Here they are:
1098 # sizeof(CONTEXT) 1232
1099 # DISPATCHER_CONTEXT.ControlPc 0
1100 # DISPATCHER_CONTEXT.ImageBase 8
1101 # DISPATCHER_CONTEXT.FunctionEntry 16
1102 # DISPATCHER_CONTEXT.EstablisherFrame 24
1103 # DISPATCHER_CONTEXT.TargetIp 32
1104 # DISPATCHER_CONTEXT.ContextRecord 40
1105 # DISPATCHER_CONTEXT.LanguageHandler 48
1106 # DISPATCHER_CONTEXT.HandlerData 56
1107 # UNW_FLAG_NHANDLER 0
1108 # ExceptionContinueSearch 1
1110 # In order to tie the handler to the function one has to compose
1111 # couple of structures: one for .xdata segment and one for .pdata.
1113 # UNWIND_INFO structure for .xdata segment would be
1115 # function_unwind_info:
1119 # This structure designates exception handler for a function with
1120 # zero-length prologue, no stack frame or frame register.
1122 # To facilitate composing of .pdata structures, auto-generated "gear"
1123 # prologue copies rsp value to rax and denotes next instruction with
1124 # .LSEH_begin_{function_name} label. This essentially defines the SEH
1125 # styling rule mentioned in the beginning. Position of this label is
1126 # chosen in such manner that possible exceptions raised in the "gear"
1127 # prologue would be accounted to caller and unwound from latter's frame.
1128 # End of function is marked with respective .LSEH_end_{function_name}
1129 # label. To summarize, .pdata segment would contain
1131 # .rva .LSEH_begin_function
1132 # .rva .LSEH_end_function
1133 # .rva function_unwind_info
1135 # Reference to function_unwind_info from .xdata segment is the anchor.
1136 # In case you wonder why references are 32-bit .rvas and not 64-bit
1137 # .quads. References put into these two segments are required to be
1138 # *relative* to the base address of the current binary module, a.k.a.
1139 # image base. No Win64 module, be it .exe or .dll, can be larger than
1140 # 2GB and thus such relative references can be and are accommodated in
1143 # Having reviewed the example function code, one can argue that "movq
1144 # %rsp,%rax" above is redundant. It is not! Keep in mind that on Unix
1145 # rax would contain an undefined value. If this "offends" you, use
1146 # another register and refrain from modifying rax till magic_point is
1147 # reached, i.e. as if it was a non-volatile register. If more registers
1148 # are required prior [variable] frame setup is completed, note that
1149 # nobody says that you can have only one "magic point." You can
1150 # "liberate" non-volatile registers by denoting last stack off-load
1151 # instruction and reflecting it in finer grade unwind logic in handler.
1152 # After all, isn't it why it's called *language-specific* handler...
1154 # Attentive reader can notice that exceptions would be mishandled in
1155 # auto-generated "gear" epilogue. Well, exception effectively can't
1156 # occur there, because if memory area used by it was subject to
1157 # segmentation violation, then it would be raised upon call to the
1158 # function (and as already mentioned be accounted to caller, which is
1159 # not a problem). If you're still not comfortable, then define tail
1160 # "magic point" just prior ret instruction and have handler treat it...
1162 # (*) Note that we're talking about run-time, not debug-time. Lack of
1163 # unwind information makes debugging hard on both Windows and
1164 # Unix. "Unlike" referes to the fact that on Unix signal handler
1165 # will always be invoked, core dumped and appropriate exit code
1166 # returned to parent (for user notification).