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Commit | Line | Data |
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e0a65194 | 1 | #! /usr/bin/env perl |
1212818e | 2 | # Copyright 2005-2018 The OpenSSL Project Authors. All Rights Reserved. |
e0a65194 | 3 | # |
a5d9549d | 4 | # Licensed under the Apache License 2.0 (the "License"). You may not use |
e0a65194 RS |
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 | |
8 | ||
1cfd258e | 9 | |
80aa9cc9 | 10 | # Ascetic x86_64 AT&T to MASM/NASM assembler translator by <appro>. |
1cfd258e AP |
11 | # |
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... | |
16 | # | |
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. | |
20 | # | |
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... | |
26 | # | |
27 | # Currently recognized limitations: | |
28 | # | |
29 | # - can't use multiple ops per line; | |
1cfd258e AP |
30 | # |
31 | # Dual-ABI styling rules. | |
32 | # | |
80aa9cc9 AP |
33 | # 1. Adhere to Unix register and stack layout [see cross-reference |
34 | # ABI "card" at the end for explanation]. | |
1cfd258e AP |
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 | |
4b450519 | 39 | # unified Win64 prologue and epilogue automatically. If you want |
1cfd258e | 40 | # to take care of ABI differences yourself, tag functions as |
4b450519 AP |
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:-) | |
85253772 AP |
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 | |
9d301cfe | 54 | # modes. |
80aa9cc9 AP |
55 | # |
56 | # 8. In order to provide for structured exception handling unified | |
57 | # Win64 prologue copies %rsp value to %rax. For further details | |
58 | # see SEH paragraph at the end. | |
85253772 | 59 | # 9. .init segment is allowed to contain calls to functions only. |
f9a152bd AP |
60 | # a. If function accepts more than 4 arguments *and* >4th argument |
61 | # is declared as non 64-bit value, do clear its upper part. | |
80aa9cc9 | 62 | \f |
c25278db DB |
63 | |
64 | use strict; | |
65 | ||
85253772 AP |
66 | my $flavour = shift; |
67 | my $output = shift; | |
68 | if ($flavour =~ /\./) { $output = $flavour; undef $flavour; } | |
932cc129 | 69 | |
b2ae61ec AP |
70 | open STDOUT,">$output" || die "can't open $output: $!" |
71 | if (defined($output)); | |
1cfd258e | 72 | |
85253772 AP |
73 | my $gas=1; $gas=0 if ($output =~ /\.asm$/); |
74 | my $elf=1; $elf=0 if (!$gas); | |
75 | my $win64=0; | |
76 | my $prefix=""; | |
93c4ba07 | 77 | my $decor=".L"; |
a23e3dbe | 78 | |
8ab9025e | 79 | my $masmref=8 + 50727*2**-32; # 8.00.50727 shipped with VS2005 |
9b634c9b | 80 | my $masm=0; |
a23e3dbe AP |
81 | my $PTR=" PTR"; |
82 | ||
9b634c9b | 83 | my $nasmref=2.03; |
a23e3dbe AP |
84 | my $nasm=0; |
85 | ||
f9a152bd AP |
86 | if ($flavour eq "mingw64") { $gas=1; $elf=0; $win64=1; |
87 | $prefix=`echo __USER_LABEL_PREFIX__ | $ENV{CC} -E -P -`; | |
9ba96fbb | 88 | $prefix =~ s|\R$||; # Better chomp |
f9a152bd | 89 | } |
93c4ba07 AP |
90 | elsif ($flavour eq "macosx") { $gas=1; $elf=0; $prefix="_"; $decor="L\$"; } |
91 | elsif ($flavour eq "masm") { $gas=0; $elf=0; $masm=$masmref; $win64=1; $decor="\$L\$"; } | |
92 | elsif ($flavour eq "nasm") { $gas=0; $elf=0; $nasm=$nasmref; $win64=1; $decor="\$L\$"; $PTR=""; } | |
85253772 | 93 | elsif (!$gas) |
9b634c9b AP |
94 | { if ($ENV{ASM} =~ m/nasm/ && `nasm -v` =~ m/version ([0-9]+)\.([0-9]+)/i) |
95 | { $nasm = $1 + $2*0.01; $PTR=""; } | |
a23e3dbe AP |
96 | elsif (`ml64 2>&1` =~ m/Version ([0-9]+)\.([0-9]+)(\.([0-9]+))?/) |
97 | { $masm = $1 + $2*2**-16 + $4*2**-32; } | |
e09b6216 | 98 | die "no assembler found on %PATH%" if (!($nasm || $masm)); |
85253772 AP |
99 | $win64=1; |
100 | $elf=0; | |
93c4ba07 | 101 | $decor="\$L\$"; |
a23e3dbe | 102 | } |
1cfd258e | 103 | |
51994e50 L |
104 | my $cet_property; |
105 | if ($flavour =~ /elf/) { | |
106 | # Always generate .note.gnu.property section for ELF outputs to | |
107 | # mark Intel CET support since all input files must be marked | |
108 | # with Intel CET support in order for linker to mark output with | |
109 | # Intel CET support. | |
110 | my $p2align=3; $p2align=2 if ($flavour eq "elf32"); | |
111 | $cet_property = <<_____; | |
b2b43d1b | 112 | .section ".note.gnu.property", "a" |
51994e50 | 113 | .p2align $p2align |
b2b43d1b RL |
114 | .long 1f - 0f |
115 | .long 4f - 1f | |
116 | .long 5 | |
117 | 0: | |
118 | .asciz "GNU" | |
119 | 1: | |
51994e50 | 120 | .p2align $p2align |
b2b43d1b RL |
121 | .long 0xc0000002 |
122 | .long 3f - 2f | |
123 | 2: | |
124 | .long 3 | |
125 | 3: | |
51994e50 | 126 | .p2align $p2align |
b2b43d1b RL |
127 | 4: |
128 | _____ | |
51994e50 L |
129 | } |
130 | ||
1cfd258e AP |
131 | my $current_segment; |
132 | my $current_function; | |
9b634c9b | 133 | my %globals; |
1cfd258e AP |
134 | |
135 | { package opcode; # pick up opcodes | |
136 | sub re { | |
c25278db DB |
137 | my ($class, $line) = @_; |
138 | my $self = {}; | |
139 | my $ret; | |
1cfd258e | 140 | |
c25278db DB |
141 | if ($$line =~ /^([a-z][a-z0-9]*)/i) { |
142 | bless $self,$class; | |
1cfd258e AP |
143 | $self->{op} = $1; |
144 | $ret = $self; | |
c25278db | 145 | $$line = substr($$line,@+[0]); $$line =~ s/^\s+//; |
1cfd258e AP |
146 | |
147 | undef $self->{sz}; | |
272ba870 | 148 | if ($self->{op} =~ /^(movz)x?([bw]).*/) { # movz is pain... |
1cfd258e | 149 | $self->{op} = $1; |
272ba870 | 150 | $self->{sz} = $2; |
9b634c9b | 151 | } elsif ($self->{op} =~ /call|jmp/) { |
fead2539 | 152 | $self->{sz} = ""; |
a9e790b9 | 153 | } elsif ($self->{op} =~ /^p/ && $' !~ /^(ush|op|insrw)/) { # SSEn |
fead2539 | 154 | $self->{sz} = ""; |
526ab896 | 155 | } elsif ($self->{op} =~ /^[vk]/) { # VEX or k* such as kmov |
0a9a692e | 156 | $self->{sz} = ""; |
c25278db | 157 | } elsif ($self->{op} =~ /mov[dq]/ && $$line =~ /%xmm/) { |
c7b903e0 | 158 | $self->{sz} = ""; |
a078befc | 159 | } elsif ($self->{op} =~ /([a-z]{3,})([qlwb])$/) { |
1cfd258e AP |
160 | $self->{op} = $1; |
161 | $self->{sz} = $2; | |
162 | } | |
163 | } | |
164 | $ret; | |
165 | } | |
166 | sub size { | |
c25278db | 167 | my ($self, $sz) = @_; |
1cfd258e AP |
168 | $self->{sz} = $sz if (defined($sz) && !defined($self->{sz})); |
169 | $self->{sz}; | |
170 | } | |
171 | sub out { | |
172 | my $self = shift; | |
85253772 | 173 | if ($gas) { |
932cc129 | 174 | if ($self->{op} eq "movz") { # movz is pain... |
1cfd258e | 175 | sprintf "%s%s%s",$self->{op},$self->{sz},shift; |
609b0852 | 176 | } elsif ($self->{op} =~ /^set/) { |
932cc129 | 177 | "$self->{op}"; |
1cfd258e | 178 | } elsif ($self->{op} eq "ret") { |
85253772 AP |
179 | my $epilogue = ""; |
180 | if ($win64 && $current_function->{abi} eq "svr4") { | |
181 | $epilogue = "movq 8(%rsp),%rdi\n\t" . | |
182 | "movq 16(%rsp),%rsi\n\t"; | |
183 | } | |
184 | $epilogue . ".byte 0xf3,0xc3"; | |
185 | } elsif ($self->{op} eq "call" && !$elf && $current_segment eq ".init") { | |
186 | ".p2align\t3\n\t.quad"; | |
1cfd258e AP |
187 | } else { |
188 | "$self->{op}$self->{sz}"; | |
189 | } | |
190 | } else { | |
a078befc | 191 | $self->{op} =~ s/^movz/movzx/; |
1cfd258e AP |
192 | if ($self->{op} eq "ret") { |
193 | $self->{op} = ""; | |
85253772 | 194 | if ($win64 && $current_function->{abi} eq "svr4") { |
67b8bf4d AP |
195 | $self->{op} = "mov rdi,QWORD$PTR\[8+rsp\]\t;WIN64 epilogue\n\t". |
196 | "mov rsi,QWORD$PTR\[16+rsp\]\n\t"; | |
1cfd258e AP |
197 | } |
198 | $self->{op} .= "DB\t0F3h,0C3h\t\t;repret"; | |
85253772 | 199 | } elsif ($self->{op} =~ /^(pop|push)f/) { |
80aa9cc9 | 200 | $self->{op} .= $self->{sz}; |
85253772 | 201 | } elsif ($self->{op} eq "call" && $current_segment eq ".CRT\$XCU") { |
d6522548 | 202 | $self->{op} = "\tDQ"; |
609b0852 | 203 | } |
1cfd258e AP |
204 | $self->{op}; |
205 | } | |
206 | } | |
85253772 | 207 | sub mnemonic { |
c25278db | 208 | my ($self, $op) = @_; |
85253772 AP |
209 | $self->{op}=$op if (defined($op)); |
210 | $self->{op}; | |
211 | } | |
1cfd258e AP |
212 | } |
213 | { package const; # pick up constants, which start with $ | |
214 | sub re { | |
c25278db DB |
215 | my ($class, $line) = @_; |
216 | my $self = {}; | |
217 | my $ret; | |
1cfd258e | 218 | |
c25278db DB |
219 | if ($$line =~ /^\$([^,]+)/) { |
220 | bless $self, $class; | |
1cfd258e AP |
221 | $self->{value} = $1; |
222 | $ret = $self; | |
c25278db | 223 | $$line = substr($$line,@+[0]); $$line =~ s/^\s+//; |
1cfd258e AP |
224 | } |
225 | $ret; | |
226 | } | |
227 | sub out { | |
228 | my $self = shift; | |
5d0d60e2 | 229 | |
6e42e3ff | 230 | $self->{value} =~ s/\b(0b[0-1]+)/oct($1)/eig; |
85253772 | 231 | if ($gas) { |
e84b663a AP |
232 | # Solaris /usr/ccs/bin/as can't handle multiplications |
233 | # in $self->{value} | |
fd7dc201 | 234 | my $value = $self->{value}; |
67b8bf4d | 235 | no warnings; # oct might complain about overflow, ignore here... |
fd7dc201 AP |
236 | $value =~ s/(?<![\w\$\.])(0x?[0-9a-f]+)/oct($1)/egi; |
237 | if ($value =~ s/([0-9]+\s*[\*\/\%]\s*[0-9]+)/eval($1)/eg) { | |
238 | $self->{value} = $value; | |
239 | } | |
5d0d60e2 AP |
240 | sprintf "\$%s",$self->{value}; |
241 | } else { | |
c47aea8a AP |
242 | my $value = $self->{value}; |
243 | $value =~ s/0x([0-9a-f]+)/0$1h/ig if ($masm); | |
244 | sprintf "%s",$value; | |
5d0d60e2 | 245 | } |
1cfd258e AP |
246 | } |
247 | } | |
248 | { package ea; # pick up effective addresses: expr(%reg,%reg,scale) | |
e09b6216 AP |
249 | |
250 | my %szmap = ( b=>"BYTE$PTR", w=>"WORD$PTR", | |
251 | l=>"DWORD$PTR", d=>"DWORD$PTR", | |
252 | q=>"QWORD$PTR", o=>"OWORD$PTR", | |
253 | x=>"XMMWORD$PTR", y=>"YMMWORD$PTR", | |
254 | z=>"ZMMWORD$PTR" ) if (!$gas); | |
255 | ||
1cfd258e | 256 | sub re { |
c25278db DB |
257 | my ($class, $line, $opcode) = @_; |
258 | my $self = {}; | |
259 | my $ret; | |
1cfd258e | 260 | |
67b8bf4d | 261 | # optional * ----vvv--- appears in indirect jmp/call |
526ab896 | 262 | if ($$line =~ /^(\*?)([^\(,]*)\(([%\w,]+)\)((?:{[^}]+})*)/) { |
c25278db | 263 | bless $self, $class; |
9b634c9b AP |
264 | $self->{asterisk} = $1; |
265 | $self->{label} = $2; | |
266 | ($self->{base},$self->{index},$self->{scale})=split(/,/,$3); | |
1cfd258e | 267 | $self->{scale} = 1 if (!defined($self->{scale})); |
e09b6216 | 268 | $self->{opmask} = $4; |
1cfd258e | 269 | $ret = $self; |
c25278db | 270 | $$line = substr($$line,@+[0]); $$line =~ s/^\s+//; |
1cfd258e | 271 | |
85253772 | 272 | if ($win64 && $self->{label} =~ s/\@GOTPCREL//) { |
c25278db DB |
273 | die if ($opcode->mnemonic() ne "mov"); |
274 | $opcode->mnemonic("lea"); | |
85253772 | 275 | } |
1cfd258e AP |
276 | $self->{base} =~ s/^%//; |
277 | $self->{index} =~ s/^%// if (defined($self->{index})); | |
c25278db | 278 | $self->{opcode} = $opcode; |
1cfd258e AP |
279 | } |
280 | $ret; | |
281 | } | |
282 | sub size {} | |
283 | sub out { | |
c25278db | 284 | my ($self, $sz) = @_; |
1cfd258e | 285 | |
85253772 | 286 | $self->{label} =~ s/([_a-z][_a-z0-9]*)/$globals{$1} or $1/gei; |
93c4ba07 | 287 | $self->{label} =~ s/\.L/$decor/g; |
85253772 | 288 | |
afbe674e AP |
289 | # Silently convert all EAs to 64-bit. This is required for |
290 | # elder GNU assembler and results in more compact code, | |
291 | # *but* most importantly AES module depends on this feature! | |
292 | $self->{index} =~ s/^[er](.?[0-9xpi])[d]?$/r\1/; | |
293 | $self->{base} =~ s/^[er](.?[0-9xpi])[d]?$/r\1/; | |
294 | ||
6fa4c7c4 | 295 | # Solaris /usr/ccs/bin/as can't handle multiplications |
82e08930 | 296 | # in $self->{label}... |
6fa4c7c4 AP |
297 | use integer; |
298 | $self->{label} =~ s/(?<![\w\$\.])(0x?[0-9a-f]+)/oct($1)/egi; | |
667053a2 | 299 | $self->{label} =~ s/\b([0-9]+\s*[\*\/\%]\s*[0-9]+)\b/eval($1)/eg; |
82e08930 AP |
300 | |
301 | # Some assemblers insist on signed presentation of 32-bit | |
302 | # offsets, but sign extension is a tricky business in perl... | |
303 | if ((1<<31)<<1) { | |
304 | $self->{label} =~ s/\b([0-9]+)\b/$1<<32>>32/eg; | |
305 | } else { | |
306 | $self->{label} =~ s/\b([0-9]+)\b/$1>>0/eg; | |
307 | } | |
6fa4c7c4 | 308 | |
e09b6216 | 309 | # if base register is %rbp or %r13, see if it's possible to |
fa3f8355 | 310 | # flip base and index registers [for better performance] |
22de0e65 AP |
311 | if (!$self->{label} && $self->{index} && $self->{scale}==1 && |
312 | $self->{base} =~ /(rbp|r13)/) { | |
313 | $self->{base} = $self->{index}; $self->{index} = $1; | |
314 | } | |
315 | ||
85253772 | 316 | if ($gas) { |
93c4ba07 | 317 | $self->{label} =~ s/^___imp_/__imp__/ if ($flavour eq "mingw64"); |
4b450519 | 318 | |
1cfd258e | 319 | if (defined($self->{index})) { |
526ab896 AP |
320 | sprintf "%s%s(%s,%%%s,%d)%s", |
321 | $self->{asterisk},$self->{label}, | |
b5c6aab5 | 322 | $self->{base}?"%$self->{base}":"", |
526ab896 | 323 | $self->{index},$self->{scale}, |
e09b6216 | 324 | $self->{opmask}; |
5d0d60e2 | 325 | } else { |
526ab896 | 326 | sprintf "%s%s(%%%s)%s", $self->{asterisk},$self->{label}, |
e09b6216 | 327 | $self->{base},$self->{opmask}; |
1cfd258e AP |
328 | } |
329 | } else { | |
70cf3095 | 330 | $self->{label} =~ s/\./\$/g; |
f9a152bd | 331 | $self->{label} =~ s/(?<![\w\$\.])0x([0-9a-f]+)/0$1h/ig; |
70cf3095 | 332 | $self->{label} = "($self->{label})" if ($self->{label} =~ /[\*\+\-\/]/); |
1b0fe79f | 333 | |
c25278db DB |
334 | my $mnemonic = $self->{opcode}->mnemonic(); |
335 | ($self->{asterisk}) && ($sz="q") || | |
336 | ($mnemonic =~ /^v?mov([qd])$/) && ($sz=$1) || | |
337 | ($mnemonic =~ /^v?pinsr([qdwb])$/) && ($sz=$1) || | |
338 | ($mnemonic =~ /^vpbroadcast([qdwb])$/) && ($sz=$1) || | |
339 | ($mnemonic =~ /^v(?!perm)[a-z]+[fi]128$/) && ($sz="x"); | |
70cf3095 | 340 | |
e09b6216 | 341 | $self->{opmask} =~ s/%(k[0-7])/$1/; |
526ab896 | 342 | |
1cfd258e | 343 | if (defined($self->{index})) { |
526ab896 | 344 | sprintf "%s[%s%s*%d%s]%s",$szmap{$sz}, |
a23e3dbe | 345 | $self->{label}?"$self->{label}+":"", |
1cfd258e | 346 | $self->{index},$self->{scale}, |
526ab896 | 347 | $self->{base}?"+$self->{base}":"", |
e09b6216 | 348 | $self->{opmask}; |
932cc129 | 349 | } elsif ($self->{base} eq "rip") { |
a23e3dbe | 350 | sprintf "%s[%s]",$szmap{$sz},$self->{label}; |
5d0d60e2 | 351 | } else { |
526ab896 | 352 | sprintf "%s[%s%s]%s", $szmap{$sz}, |
a23e3dbe | 353 | $self->{label}?"$self->{label}+":"", |
e09b6216 | 354 | $self->{base},$self->{opmask}; |
1cfd258e AP |
355 | } |
356 | } | |
357 | } | |
358 | } | |
359 | { package register; # pick up registers, which start with %. | |
360 | sub re { | |
6a4ea002 | 361 | my ($class, $line, $opcode) = @_; |
1cfd258e | 362 | my $self = {}; |
c25278db | 363 | my $ret; |
1cfd258e | 364 | |
6a4ea002 | 365 | # optional * ----vvv--- appears in indirect jmp/call |
526ab896 | 366 | if ($$line =~ /^(\*?)%(\w+)((?:{[^}]+})*)/) { |
1cfd258e | 367 | bless $self,$class; |
9b634c9b AP |
368 | $self->{asterisk} = $1; |
369 | $self->{value} = $2; | |
e09b6216 | 370 | $self->{opmask} = $3; |
6a4ea002 | 371 | $opcode->size($self->size()); |
1cfd258e | 372 | $ret = $self; |
c25278db | 373 | $$line = substr($$line,@+[0]); $$line =~ s/^\s+//; |
1cfd258e AP |
374 | } |
375 | $ret; | |
376 | } | |
377 | sub size { | |
378 | my $self = shift; | |
c25278db | 379 | my $ret; |
1cfd258e AP |
380 | |
381 | if ($self->{value} =~ /^r[\d]+b$/i) { $ret="b"; } | |
382 | elsif ($self->{value} =~ /^r[\d]+w$/i) { $ret="w"; } | |
383 | elsif ($self->{value} =~ /^r[\d]+d$/i) { $ret="l"; } | |
384 | elsif ($self->{value} =~ /^r[\w]+$/i) { $ret="q"; } | |
385 | elsif ($self->{value} =~ /^[a-d][hl]$/i){ $ret="b"; } | |
386 | elsif ($self->{value} =~ /^[\w]{2}l$/i) { $ret="b"; } | |
387 | elsif ($self->{value} =~ /^[\w]{2}$/i) { $ret="w"; } | |
388 | elsif ($self->{value} =~ /^e[a-z]{2}$/i){ $ret="l"; } | |
389 | ||
390 | $ret; | |
391 | } | |
392 | sub out { | |
393 | my $self = shift; | |
526ab896 AP |
394 | if ($gas) { sprintf "%s%%%s%s", $self->{asterisk}, |
395 | $self->{value}, | |
e09b6216 AP |
396 | $self->{opmask}; } |
397 | else { $self->{opmask} =~ s/%(k[0-7])/$1/; | |
398 | $self->{value}.$self->{opmask}; } | |
1cfd258e AP |
399 | } |
400 | } | |
401 | { package label; # pick up labels, which end with : | |
402 | sub re { | |
c25278db DB |
403 | my ($class, $line) = @_; |
404 | my $self = {}; | |
405 | my $ret; | |
1cfd258e | 406 | |
c25278db DB |
407 | if ($$line =~ /(^[\.\w]+)\:/) { |
408 | bless $self,$class; | |
1cfd258e AP |
409 | $self->{value} = $1; |
410 | $ret = $self; | |
c25278db | 411 | $$line = substr($$line,@+[0]); $$line =~ s/^\s+//; |
1cfd258e | 412 | |
93c4ba07 | 413 | $self->{value} =~ s/^\.L/$decor/; |
1cfd258e AP |
414 | } |
415 | $ret; | |
416 | } | |
417 | sub out { | |
418 | my $self = shift; | |
419 | ||
85253772 AP |
420 | if ($gas) { |
421 | my $func = ($globals{$self->{value}} or $self->{value}) . ":"; | |
e09b6216 AP |
422 | if ($win64 && $current_function->{name} eq $self->{value} |
423 | && $current_function->{abi} eq "svr4") { | |
85253772 AP |
424 | $func .= "\n"; |
425 | $func .= " movq %rdi,8(%rsp)\n"; | |
426 | $func .= " movq %rsi,16(%rsp)\n"; | |
427 | $func .= " movq %rsp,%rax\n"; | |
93c4ba07 | 428 | $func .= "${decor}SEH_begin_$current_function->{name}:\n"; |
85253772 AP |
429 | my $narg = $current_function->{narg}; |
430 | $narg=6 if (!defined($narg)); | |
431 | $func .= " movq %rcx,%rdi\n" if ($narg>0); | |
432 | $func .= " movq %rdx,%rsi\n" if ($narg>1); | |
433 | $func .= " movq %r8,%rdx\n" if ($narg>2); | |
434 | $func .= " movq %r9,%rcx\n" if ($narg>3); | |
435 | $func .= " movq 40(%rsp),%r8\n" if ($narg>4); | |
436 | $func .= " movq 48(%rsp),%r9\n" if ($narg>5); | |
437 | } | |
438 | $func; | |
439 | } elsif ($self->{value} ne "$current_function->{name}") { | |
c25278db DB |
440 | # Make all labels in masm global. |
441 | $self->{value} .= ":" if ($masm); | |
85253772 AP |
442 | $self->{value} . ":"; |
443 | } elsif ($win64 && $current_function->{abi} eq "svr4") { | |
9b634c9b AP |
444 | my $func = "$current_function->{name}" . |
445 | ($nasm ? ":" : "\tPROC $current_function->{scope}") . | |
446 | "\n"; | |
67b8bf4d AP |
447 | $func .= " mov QWORD$PTR\[8+rsp\],rdi\t;WIN64 prologue\n"; |
448 | $func .= " mov QWORD$PTR\[16+rsp\],rsi\n"; | |
80aa9cc9 | 449 | $func .= " mov rax,rsp\n"; |
93c4ba07 | 450 | $func .= "${decor}SEH_begin_$current_function->{name}:"; |
80aa9cc9 AP |
451 | $func .= ":" if ($masm); |
452 | $func .= "\n"; | |
1cfd258e AP |
453 | my $narg = $current_function->{narg}; |
454 | $narg=6 if (!defined($narg)); | |
455 | $func .= " mov rdi,rcx\n" if ($narg>0); | |
456 | $func .= " mov rsi,rdx\n" if ($narg>1); | |
457 | $func .= " mov rdx,r8\n" if ($narg>2); | |
458 | $func .= " mov rcx,r9\n" if ($narg>3); | |
67b8bf4d AP |
459 | $func .= " mov r8,QWORD$PTR\[40+rsp\]\n" if ($narg>4); |
460 | $func .= " mov r9,QWORD$PTR\[48+rsp\]\n" if ($narg>5); | |
1cfd258e AP |
461 | $func .= "\n"; |
462 | } else { | |
9b634c9b AP |
463 | "$current_function->{name}". |
464 | ($nasm ? ":" : "\tPROC $current_function->{scope}"); | |
1cfd258e AP |
465 | } |
466 | } | |
467 | } | |
7e12cdb5 | 468 | { package expr; # pick up expressions |
1cfd258e | 469 | sub re { |
c25278db DB |
470 | my ($class, $line, $opcode) = @_; |
471 | my $self = {}; | |
472 | my $ret; | |
1cfd258e | 473 | |
c25278db DB |
474 | if ($$line =~ /(^[^,]+)/) { |
475 | bless $self,$class; | |
1cfd258e AP |
476 | $self->{value} = $1; |
477 | $ret = $self; | |
c25278db | 478 | $$line = substr($$line,@+[0]); $$line =~ s/^\s+//; |
1cfd258e | 479 | |
85253772 AP |
480 | $self->{value} =~ s/\@PLT// if (!$elf); |
481 | $self->{value} =~ s/([_a-z][_a-z0-9]*)/$globals{$1} or $1/gei; | |
93c4ba07 | 482 | $self->{value} =~ s/\.L/$decor/g; |
c25278db | 483 | $self->{opcode} = $opcode; |
1cfd258e AP |
484 | } |
485 | $ret; | |
486 | } | |
487 | sub out { | |
488 | my $self = shift; | |
c25278db | 489 | if ($nasm && $self->{opcode}->mnemonic()=~m/^j(?![re]cxz)/) { |
9b634c9b AP |
490 | "NEAR ".$self->{value}; |
491 | } else { | |
492 | $self->{value}; | |
493 | } | |
1cfd258e AP |
494 | } |
495 | } | |
a3b5684f AP |
496 | { package cfi_directive; |
497 | # CFI directives annotate instructions that are significant for | |
498 | # stack unwinding procedure compliant with DWARF specification, | |
499 | # see http://dwarfstd.org/. Besides naturally expected for this | |
500 | # script platform-specific filtering function, this module adds | |
501 | # three auxiliary synthetic directives not recognized by [GNU] | |
502 | # assembler: | |
503 | # | |
504 | # - .cfi_push to annotate push instructions in prologue, which | |
505 | # translates to .cfi_adjust_cfa_offset (if needed) and | |
506 | # .cfi_offset; | |
507 | # - .cfi_pop to annotate pop instructions in epilogue, which | |
508 | # translates to .cfi_adjust_cfa_offset (if needed) and | |
509 | # .cfi_restore; | |
510 | # - [and most notably] .cfi_cfa_expression which encodes | |
511 | # DW_CFA_def_cfa_expression and passes it to .cfi_escape as | |
512 | # byte vector; | |
513 | # | |
514 | # CFA expressions were introduced in DWARF specification version | |
515 | # 3 and describe how to deduce CFA, Canonical Frame Address. This | |
516 | # becomes handy if your stack frame is variable and you can't | |
517 | # spare register for [previous] frame pointer. Suggested directive | |
518 | # syntax is made-up mix of DWARF operator suffixes [subset of] | |
519 | # and references to registers with optional bias. Following example | |
520 | # describes offloaded *original* stack pointer at specific offset | |
521 | # from *current* stack pointer: | |
522 | # | |
523 | # .cfi_cfa_expression %rsp+40,deref,+8 | |
524 | # | |
525 | # Final +8 has everything to do with the fact that CFA is defined | |
526 | # as reference to top of caller's stack, and on x86_64 call to | |
527 | # subroutine pushes 8-byte return address. In other words original | |
528 | # stack pointer upon entry to a subroutine is 8 bytes off from CFA. | |
529 | ||
530 | # Below constants are taken from "DWARF Expressions" section of the | |
531 | # DWARF specification, section is numbered 7.7 in versions 3 and 4. | |
532 | my %DW_OP_simple = ( # no-arg operators, mapped directly | |
533 | deref => 0x06, dup => 0x12, | |
534 | drop => 0x13, over => 0x14, | |
535 | pick => 0x15, swap => 0x16, | |
536 | rot => 0x17, xderef => 0x18, | |
537 | ||
538 | abs => 0x19, and => 0x1a, | |
539 | div => 0x1b, minus => 0x1c, | |
540 | mod => 0x1d, mul => 0x1e, | |
541 | neg => 0x1f, not => 0x20, | |
542 | or => 0x21, plus => 0x22, | |
543 | shl => 0x24, shr => 0x25, | |
544 | shra => 0x26, xor => 0x27, | |
545 | ); | |
546 | ||
547 | my %DW_OP_complex = ( # used in specific subroutines | |
548 | constu => 0x10, # uleb128 | |
549 | consts => 0x11, # sleb128 | |
550 | plus_uconst => 0x23, # uleb128 | |
551 | lit0 => 0x30, # add 0-31 to opcode | |
552 | reg0 => 0x50, # add 0-31 to opcode | |
553 | breg0 => 0x70, # add 0-31 to opcole, sleb128 | |
554 | regx => 0x90, # uleb28 | |
555 | fbreg => 0x91, # sleb128 | |
556 | bregx => 0x92, # uleb128, sleb128 | |
557 | piece => 0x93, # uleb128 | |
558 | ); | |
559 | ||
560 | # Following constants are defined in x86_64 ABI supplement, for | |
46f4e1be | 561 | # example available at https://www.uclibc.org/docs/psABI-x86_64.pdf, |
a3b5684f AP |
562 | # see section 3.7 "Stack Unwind Algorithm". |
563 | my %DW_reg_idx = ( | |
564 | "%rax"=>0, "%rdx"=>1, "%rcx"=>2, "%rbx"=>3, | |
565 | "%rsi"=>4, "%rdi"=>5, "%rbp"=>6, "%rsp"=>7, | |
566 | "%r8" =>8, "%r9" =>9, "%r10"=>10, "%r11"=>11, | |
567 | "%r12"=>12, "%r13"=>13, "%r14"=>14, "%r15"=>15 | |
568 | ); | |
569 | ||
570 | my ($cfa_reg, $cfa_rsp); | |
c0e8e500 | 571 | my @cfa_stack; |
a3b5684f AP |
572 | |
573 | # [us]leb128 format is variable-length integer representation base | |
574 | # 2^128, with most significant bit of each byte being 0 denoting | |
46f4e1be | 575 | # *last* most significant digit. See "Variable Length Data" in the |
a3b5684f AP |
576 | # DWARF specification, numbered 7.6 at least in versions 3 and 4. |
577 | sub sleb128 { | |
578 | use integer; # get right shift extend sign | |
579 | ||
580 | my $val = shift; | |
581 | my $sign = ($val < 0) ? -1 : 0; | |
582 | my @ret = (); | |
583 | ||
584 | while(1) { | |
585 | push @ret, $val&0x7f; | |
586 | ||
587 | # see if remaining bits are same and equal to most | |
588 | # significant bit of the current digit, if so, it's | |
589 | # last digit... | |
590 | last if (($val>>6) == $sign); | |
591 | ||
592 | @ret[-1] |= 0x80; | |
593 | $val >>= 7; | |
594 | } | |
595 | ||
596 | return @ret; | |
597 | } | |
598 | sub uleb128 { | |
599 | my $val = shift; | |
600 | my @ret = (); | |
601 | ||
602 | while(1) { | |
603 | push @ret, $val&0x7f; | |
604 | ||
605 | # see if it's last significant digit... | |
606 | last if (($val >>= 7) == 0); | |
607 | ||
608 | @ret[-1] |= 0x80; | |
609 | } | |
610 | ||
611 | return @ret; | |
612 | } | |
613 | sub const { | |
614 | my $val = shift; | |
615 | ||
616 | if ($val >= 0 && $val < 32) { | |
617 | return ($DW_OP_complex{lit0}+$val); | |
618 | } | |
619 | return ($DW_OP_complex{consts}, sleb128($val)); | |
620 | } | |
621 | sub reg { | |
622 | my $val = shift; | |
623 | ||
624 | return if ($val !~ m/^(%r\w+)(?:([\+\-])((?:0x)?[0-9a-f]+))?/); | |
625 | ||
626 | my $reg = $DW_reg_idx{$1}; | |
627 | my $off = eval ("0 $2 $3"); | |
628 | ||
629 | return (($DW_OP_complex{breg0} + $reg), sleb128($off)); | |
630 | # Yes, we use DW_OP_bregX+0 to push register value and not | |
631 | # DW_OP_regX, because latter would require even DW_OP_piece, | |
632 | # which would be a waste under the circumstances. If you have | |
633 | # to use DWP_OP_reg, use "regx:N"... | |
634 | } | |
635 | sub cfa_expression { | |
636 | my $line = shift; | |
637 | my @ret; | |
638 | ||
639 | foreach my $token (split(/,\s*/,$line)) { | |
640 | if ($token =~ /^%r/) { | |
641 | push @ret,reg($token); | |
1cb35b47 AP |
642 | } elsif ($token =~ /((?:0x)?[0-9a-f]+)\((%r\w+)\)/) { |
643 | push @ret,reg("$2+$1"); | |
a3b5684f AP |
644 | } elsif ($token =~ /(\w+):(\-?(?:0x)?[0-9a-f]+)(U?)/i) { |
645 | my $i = 1*eval($2); | |
646 | push @ret,$DW_OP_complex{$1}, ($3 ? uleb128($i) : sleb128($i)); | |
647 | } elsif (my $i = 1*eval($token) or $token eq "0") { | |
648 | if ($token =~ /^\+/) { | |
649 | push @ret,$DW_OP_complex{plus_uconst},uleb128($i); | |
650 | } else { | |
651 | push @ret,const($i); | |
652 | } | |
653 | } else { | |
654 | push @ret,$DW_OP_simple{$token}; | |
655 | } | |
656 | } | |
657 | ||
658 | # Finally we return DW_CFA_def_cfa_expression, 15, followed by | |
659 | # length of the expression and of course the expression itself. | |
660 | return (15,scalar(@ret),@ret); | |
661 | } | |
662 | sub re { | |
663 | my ($class, $line) = @_; | |
664 | my $self = {}; | |
665 | my $ret; | |
666 | ||
88be429f | 667 | if ($$line =~ s/^\s*\.cfi_(\w+)\s*//) { |
a3b5684f AP |
668 | bless $self,$class; |
669 | $ret = $self; | |
670 | undef $self->{value}; | |
671 | my $dir = $1; | |
672 | ||
673 | SWITCH: for ($dir) { | |
674 | # What is $cfa_rsp? Effectively it's difference between %rsp | |
675 | # value and current CFA, Canonical Frame Address, which is | |
676 | # why it starts with -8. Recall that CFA is top of caller's | |
677 | # stack... | |
678 | /startproc/ && do { ($cfa_reg, $cfa_rsp) = ("%rsp", -8); last; }; | |
e0963310 DB |
679 | /endproc/ && do { ($cfa_reg, $cfa_rsp) = ("%rsp", 0); |
680 | # .cfi_remember_state directives that are not | |
681 | # matched with .cfi_restore_state are | |
682 | # unnecessary. | |
683 | die "unpaired .cfi_remember_state" if (@cfa_stack); | |
684 | last; | |
685 | }; | |
a3b5684f AP |
686 | /def_cfa_register/ |
687 | && do { $cfa_reg = $$line; last; }; | |
688 | /def_cfa_offset/ | |
689 | && do { $cfa_rsp = -1*eval($$line) if ($cfa_reg eq "%rsp"); | |
690 | last; | |
691 | }; | |
692 | /adjust_cfa_offset/ | |
693 | && do { $cfa_rsp -= 1*eval($$line) if ($cfa_reg eq "%rsp"); | |
694 | last; | |
695 | }; | |
88be429f | 696 | /def_cfa/ && do { if ($$line =~ /(%r\w+)\s*,\s*(.+)/) { |
a3b5684f AP |
697 | $cfa_reg = $1; |
698 | $cfa_rsp = -1*eval($2) if ($cfa_reg eq "%rsp"); | |
699 | } | |
700 | last; | |
701 | }; | |
702 | /push/ && do { $dir = undef; | |
703 | $cfa_rsp -= 8; | |
704 | if ($cfa_reg eq "%rsp") { | |
705 | $self->{value} = ".cfi_adjust_cfa_offset\t8\n"; | |
706 | } | |
707 | $self->{value} .= ".cfi_offset\t$$line,$cfa_rsp"; | |
708 | last; | |
709 | }; | |
710 | /pop/ && do { $dir = undef; | |
711 | $cfa_rsp += 8; | |
712 | if ($cfa_reg eq "%rsp") { | |
713 | $self->{value} = ".cfi_adjust_cfa_offset\t-8\n"; | |
714 | } | |
715 | $self->{value} .= ".cfi_restore\t$$line"; | |
716 | last; | |
717 | }; | |
718 | /cfa_expression/ | |
719 | && do { $dir = undef; | |
720 | $self->{value} = ".cfi_escape\t" . | |
721 | join(",", map(sprintf("0x%02x", $_), | |
722 | cfa_expression($$line))); | |
723 | last; | |
724 | }; | |
c0e8e500 DB |
725 | /remember_state/ |
726 | && do { push @cfa_stack, [$cfa_reg, $cfa_rsp]; | |
727 | last; | |
728 | }; | |
729 | /restore_state/ | |
730 | && do { ($cfa_reg, $cfa_rsp) = @{pop @cfa_stack}; | |
731 | last; | |
732 | }; | |
a3b5684f AP |
733 | } |
734 | ||
735 | $self->{value} = ".cfi_$dir\t$$line" if ($dir); | |
736 | ||
737 | $$line = ""; | |
738 | } | |
739 | ||
740 | return $ret; | |
741 | } | |
742 | sub out { | |
743 | my $self = shift; | |
744 | return ($elf ? $self->{value} : undef); | |
745 | } | |
746 | } | |
1cfd258e AP |
747 | { package directive; # pick up directives, which start with . |
748 | sub re { | |
c25278db DB |
749 | my ($class, $line) = @_; |
750 | my $self = {}; | |
751 | my $ret; | |
1cfd258e AP |
752 | my $dir; |
753 | ||
a3b5684f AP |
754 | # chain-call to cfi_directive |
755 | $ret = cfi_directive->re($line) and return $ret; | |
756 | ||
c25278db DB |
757 | if ($$line =~ /^\s*(\.\w+)/) { |
758 | bless $self,$class; | |
85253772 AP |
759 | $dir = $1; |
760 | $ret = $self; | |
761 | undef $self->{value}; | |
c25278db | 762 | $$line = substr($$line,@+[0]); $$line =~ s/^\s+//; |
85253772 AP |
763 | |
764 | SWITCH: for ($dir) { | |
85253772 | 765 | /\.global|\.globl|\.extern/ |
c25278db DB |
766 | && do { $globals{$$line} = $prefix . $$line; |
767 | $$line = $globals{$$line} if ($prefix); | |
85253772 AP |
768 | last; |
769 | }; | |
c25278db | 770 | /\.type/ && do { my ($sym,$type,$narg) = split(',',$$line); |
85253772 AP |
771 | if ($type eq "\@function") { |
772 | undef $current_function; | |
773 | $current_function->{name} = $sym; | |
774 | $current_function->{abi} = "svr4"; | |
775 | $current_function->{narg} = $narg; | |
776 | $current_function->{scope} = defined($globals{$sym})?"PUBLIC":"PRIVATE"; | |
777 | } elsif ($type eq "\@abi-omnipotent") { | |
778 | undef $current_function; | |
779 | $current_function->{name} = $sym; | |
780 | $current_function->{scope} = defined($globals{$sym})?"PUBLIC":"PRIVATE"; | |
781 | } | |
c25278db DB |
782 | $$line =~ s/\@abi\-omnipotent/\@function/; |
783 | $$line =~ s/\@function.*/\@function/; | |
85253772 AP |
784 | last; |
785 | }; | |
c25278db | 786 | /\.asciz/ && do { if ($$line =~ /^"(.*)"$/) { |
85253772 | 787 | $dir = ".byte"; |
c25278db | 788 | $$line = join(",",unpack("C*",$1),0); |
85253772 AP |
789 | } |
790 | last; | |
791 | }; | |
93c4ba07 | 792 | /\.rva|\.long|\.quad/ |
c25278db DB |
793 | && do { $$line =~ s/([_a-z][_a-z0-9]*)/$globals{$1} or $1/gei; |
794 | $$line =~ s/\.L/$decor/g; | |
93c4ba07 AP |
795 | last; |
796 | }; | |
85253772 AP |
797 | } |
798 | ||
799 | if ($gas) { | |
c25278db | 800 | $self->{value} = $dir . "\t" . $$line; |
85253772 AP |
801 | |
802 | if ($dir =~ /\.extern/) { | |
932cc129 | 803 | $self->{value} = ""; # swallow extern |
85253772 AP |
804 | } elsif (!$elf && $dir =~ /\.type/) { |
805 | $self->{value} = ""; | |
806 | $self->{value} = ".def\t" . ($globals{$1} or $1) . ";\t" . | |
807 | (defined($globals{$1})?".scl 2;":".scl 3;") . | |
808 | "\t.type 32;\t.endef" | |
c25278db | 809 | if ($win64 && $$line =~ /([^,]+),\@function/); |
85253772 AP |
810 | } elsif (!$elf && $dir =~ /\.size/) { |
811 | $self->{value} = ""; | |
812 | if (defined($current_function)) { | |
93c4ba07 | 813 | $self->{value} .= "${decor}SEH_end_$current_function->{name}:" |
85253772 AP |
814 | if ($win64 && $current_function->{abi} eq "svr4"); |
815 | undef $current_function; | |
816 | } | |
817 | } elsif (!$elf && $dir =~ /\.align/) { | |
c25278db | 818 | $self->{value} = ".p2align\t" . (log($$line)/log(2)); |
85253772 | 819 | } elsif ($dir eq ".section") { |
c25278db | 820 | $current_segment=$$line; |
85253772 AP |
821 | if (!$elf && $current_segment eq ".init") { |
822 | if ($flavour eq "macosx") { $self->{value} = ".mod_init_func"; } | |
823 | elsif ($flavour eq "mingw64") { $self->{value} = ".section\t.ctors"; } | |
824 | } | |
825 | } elsif ($dir =~ /\.(text|data)/) { | |
826 | $current_segment=".$1"; | |
ddc20d4d | 827 | } elsif ($dir =~ /\.hidden/) { |
c25278db | 828 | if ($flavour eq "macosx") { $self->{value} = ".private_extern\t$prefix$$line"; } |
ddc20d4d AP |
829 | elsif ($flavour eq "mingw64") { $self->{value} = ""; } |
830 | } elsif ($dir =~ /\.comm/) { | |
c25278db | 831 | $self->{value} = "$dir\t$prefix$$line"; |
ff6f9f96 | 832 | $self->{value} =~ s|,([0-9]+),([0-9]+)$|",$1,".log($2)/log(2)|e if ($flavour eq "macosx"); |
5d0d60e2 | 833 | } |
c25278db | 834 | $$line = ""; |
1cfd258e AP |
835 | return $self; |
836 | } | |
837 | ||
85253772 | 838 | # non-gas case or nasm/masm |
1cfd258e | 839 | SWITCH: for ($dir) { |
9b634c9b | 840 | /\.text/ && do { my $v=undef; |
a23e3dbe | 841 | if ($nasm) { |
9b634c9b | 842 | $v="section .text code align=64\n"; |
a23e3dbe AP |
843 | } else { |
844 | $v="$current_segment\tENDS\n" if ($current_segment); | |
9b634c9b | 845 | $current_segment = ".text\$"; |
a23e3dbe | 846 | $v.="$current_segment\tSEGMENT "; |
1b0fe79f | 847 | $v.=$masm>=$masmref ? "ALIGN(256)" : "PAGE"; |
a23e3dbe AP |
848 | $v.=" 'CODE'"; |
849 | } | |
1cfd258e AP |
850 | $self->{value} = $v; |
851 | last; | |
852 | }; | |
9b634c9b AP |
853 | /\.data/ && do { my $v=undef; |
854 | if ($nasm) { | |
855 | $v="section .data data align=8\n"; | |
856 | } else { | |
857 | $v="$current_segment\tENDS\n" if ($current_segment); | |
858 | $current_segment = "_DATA"; | |
859 | $v.="$current_segment\tSEGMENT"; | |
860 | } | |
861 | $self->{value} = $v; | |
862 | last; | |
863 | }; | |
864 | /\.section/ && do { my $v=undef; | |
c25278db DB |
865 | $$line =~ s/([^,]*).*/$1/; |
866 | $$line = ".CRT\$XCU" if ($$line eq ".init"); | |
9b634c9b | 867 | if ($nasm) { |
c25278db DB |
868 | $v="section $$line"; |
869 | if ($$line=~/\.([px])data/) { | |
9b634c9b AP |
870 | $v.=" rdata align="; |
871 | $v.=$1 eq "p"? 4 : 8; | |
c25278db | 872 | } elsif ($$line=~/\.CRT\$/i) { |
d6522548 | 873 | $v.=" rdata align=8"; |
9b634c9b AP |
874 | } |
875 | } else { | |
876 | $v="$current_segment\tENDS\n" if ($current_segment); | |
c25278db DB |
877 | $v.="$$line\tSEGMENT"; |
878 | if ($$line=~/\.([px])data/) { | |
9b634c9b AP |
879 | $v.=" READONLY"; |
880 | $v.=" ALIGN(".($1 eq "p" ? 4 : 8).")" if ($masm>=$masmref); | |
c25278db | 881 | } elsif ($$line=~/\.CRT\$/i) { |
e6903980 AP |
882 | $v.=" READONLY "; |
883 | $v.=$masm>=$masmref ? "ALIGN(8)" : "DWORD"; | |
9b634c9b AP |
884 | } |
885 | } | |
c25278db | 886 | $current_segment = $$line; |
9b634c9b AP |
887 | $self->{value} = $v; |
888 | last; | |
889 | }; | |
c25278db | 890 | /\.extern/ && do { $self->{value} = "EXTERN\t".$$line; |
9b634c9b AP |
891 | $self->{value} .= ":NEAR" if ($masm); |
892 | last; | |
893 | }; | |
80aa9cc9 AP |
894 | /\.globl|.global/ |
895 | && do { $self->{value} = $masm?"PUBLIC":"global"; | |
c25278db | 896 | $self->{value} .= "\t".$$line; |
1cfd258e AP |
897 | last; |
898 | }; | |
5d0d60e2 | 899 | /\.size/ && do { if (defined($current_function)) { |
8fe8bae1 AP |
900 | undef $self->{value}; |
901 | if ($current_function->{abi} eq "svr4") { | |
93c4ba07 | 902 | $self->{value}="${decor}SEH_end_$current_function->{name}:"; |
8fe8bae1 AP |
903 | $self->{value}.=":\n" if($masm); |
904 | } | |
4010b341 | 905 | $self->{value}.="$current_function->{name}\tENDP" if($masm && $current_function->{name}); |
1cfd258e AP |
906 | undef $current_function; |
907 | } | |
908 | last; | |
909 | }; | |
d405aa2f | 910 | /\.align/ && do { my $max = ($masm && $masm>=$masmref) ? 256 : 4096; |
c25278db | 911 | $self->{value} = "ALIGN\t".($$line>$max?$max:$$line); |
d405aa2f AP |
912 | last; |
913 | }; | |
85253772 | 914 | /\.(value|long|rva|quad)/ |
80aa9cc9 | 915 | && do { my $sz = substr($1,0,1); |
c25278db | 916 | my @arr = split(/,\s*/,$$line); |
1cfd258e | 917 | my $last = pop(@arr); |
a23e3dbe | 918 | my $conv = sub { my $var=shift; |
065c5d63 | 919 | $var=~s/^(0b[0-1]+)/oct($1)/eig; |
fead2539 | 920 | $var=~s/^0x([0-9a-f]+)/0$1h/ig if ($masm); |
85253772 | 921 | if ($sz eq "D" && ($current_segment=~/.[px]data/ || $dir eq ".rva")) |
b068a9b9 | 922 | { $var=~s/^([_a-z\$\@][_a-z0-9\$\@]*)/$nasm?"$1 wrt ..imagebase":"imagerel $1"/egi; } |
9b634c9b | 923 | $var; |
609b0852 | 924 | }; |
1cfd258e | 925 | |
85253772 | 926 | $sz =~ tr/bvlrq/BWDDQ/; |
1cfd258e | 927 | $self->{value} = "\tD$sz\t"; |
a23e3dbe AP |
928 | for (@arr) { $self->{value} .= &$conv($_).","; } |
929 | $self->{value} .= &$conv($last); | |
1cfd258e AP |
930 | last; |
931 | }; | |
c25278db | 932 | /\.byte/ && do { my @str=split(/,\s*/,$$line); |
e8169520 | 933 | map(s/(0b[0-1]+)/oct($1)/eig,@str); |
609b0852 | 934 | map(s/0x([0-9a-f]+)/0$1h/ig,@str) if ($masm); |
85253772 | 935 | while ($#str>15) { |
55eab3b7 | 936 | $self->{value}.="DB\t" |
85253772 AP |
937 | .join(",",@str[0..15])."\n"; |
938 | foreach (0..15) { shift @str; } | |
d68ff710 | 939 | } |
85253772 AP |
940 | $self->{value}.="DB\t" |
941 | .join(",",@str) if (@str); | |
d68ff710 AP |
942 | last; |
943 | }; | |
c25278db | 944 | /\.comm/ && do { my @str=split(/,\s*/,$$line); |
ddc20d4d AP |
945 | my $v=undef; |
946 | if ($nasm) { | |
301799b8 | 947 | $v.="common $prefix@str[0] @str[1]"; |
ddc20d4d AP |
948 | } else { |
949 | $v="$current_segment\tENDS\n" if ($current_segment); | |
94c64f9a | 950 | $current_segment = "_DATA"; |
ddc20d4d AP |
951 | $v.="$current_segment\tSEGMENT\n"; |
952 | $v.="COMM @str[0]:DWORD:".@str[1]/4; | |
953 | } | |
954 | $self->{value} = $v; | |
955 | last; | |
956 | }; | |
1cfd258e | 957 | } |
c25278db | 958 | $$line = ""; |
1cfd258e AP |
959 | } |
960 | ||
961 | $ret; | |
962 | } | |
963 | sub out { | |
964 | my $self = shift; | |
965 | $self->{value}; | |
966 | } | |
967 | } | |
968 | ||
1eb12c43 AP |
969 | # Upon initial x86_64 introduction SSE>2 extensions were not introduced |
970 | # yet. In order not to be bothered by tracing exact assembler versions, | |
971 | # but at the same time to provide a bare security minimum of AES-NI, we | |
972 | # hard-code some instructions. Extensions past AES-NI on the other hand | |
973 | # are traced by examining assembler version in individual perlasm | |
974 | # modules... | |
975 | ||
fead2539 AP |
976 | my %regrm = ( "%eax"=>0, "%ecx"=>1, "%edx"=>2, "%ebx"=>3, |
977 | "%esp"=>4, "%ebp"=>5, "%esi"=>6, "%edi"=>7 ); | |
978 | ||
e09b6216 AP |
979 | sub rex { |
980 | my $opcode=shift; | |
981 | my ($dst,$src,$rex)=@_; | |
982 | ||
983 | $rex|=0x04 if($dst>=8); | |
984 | $rex|=0x01 if($src>=8); | |
985 | push @$opcode,($rex|0x40) if ($rex); | |
986 | } | |
987 | ||
c7b903e0 AP |
988 | my $movq = sub { # elderly gas can't handle inter-register movq |
989 | my $arg = shift; | |
990 | my @opcode=(0x66); | |
a87ff751 | 991 | if ($arg =~ /%xmm([0-9]+),\s*%r(\w+)/) { |
c7b903e0 AP |
992 | my ($src,$dst)=($1,$2); |
993 | if ($dst !~ /[0-9]+/) { $dst = $regrm{"%e$dst"}; } | |
994 | rex(\@opcode,$src,$dst,0x8); | |
995 | push @opcode,0x0f,0x7e; | |
996 | push @opcode,0xc0|(($src&7)<<3)|($dst&7); # ModR/M | |
997 | @opcode; | |
a87ff751 | 998 | } elsif ($arg =~ /%r(\w+),\s*%xmm([0-9]+)/) { |
c7b903e0 AP |
999 | my ($src,$dst)=($2,$1); |
1000 | if ($dst !~ /[0-9]+/) { $dst = $regrm{"%e$dst"}; } | |
1001 | rex(\@opcode,$src,$dst,0x8); | |
1002 | push @opcode,0x0f,0x6e; | |
1003 | push @opcode,0xc0|(($src&7)<<3)|($dst&7); # ModR/M | |
1004 | @opcode; | |
1005 | } else { | |
1006 | (); | |
1007 | } | |
1008 | }; | |
1009 | ||
fead2539 | 1010 | my $pextrd = sub { |
a87ff751 | 1011 | if (shift =~ /\$([0-9]+),\s*%xmm([0-9]+),\s*(%\w+)/) { |
fead2539 | 1012 | my @opcode=(0x66); |
c25278db DB |
1013 | my $imm=$1; |
1014 | my $src=$2; | |
1015 | my $dst=$3; | |
fead2539 AP |
1016 | if ($dst =~ /%r([0-9]+)d/) { $dst = $1; } |
1017 | elsif ($dst =~ /%e/) { $dst = $regrm{$dst}; } | |
1018 | rex(\@opcode,$src,$dst); | |
1019 | push @opcode,0x0f,0x3a,0x16; | |
1020 | push @opcode,0xc0|(($src&7)<<3)|($dst&7); # ModR/M | |
1021 | push @opcode,$imm; | |
a9e790b9 | 1022 | @opcode; |
fead2539 | 1023 | } else { |
a9e790b9 | 1024 | (); |
fead2539 | 1025 | } |
a9e790b9 | 1026 | }; |
fead2539 AP |
1027 | |
1028 | my $pinsrd = sub { | |
a87ff751 | 1029 | if (shift =~ /\$([0-9]+),\s*(%\w+),\s*%xmm([0-9]+)/) { |
fead2539 | 1030 | my @opcode=(0x66); |
c25278db DB |
1031 | my $imm=$1; |
1032 | my $src=$2; | |
1033 | my $dst=$3; | |
b5c6aab5 | 1034 | if ($src =~ /%r([0-9]+)/) { $src = $1; } |
fead2539 AP |
1035 | elsif ($src =~ /%e/) { $src = $regrm{$src}; } |
1036 | rex(\@opcode,$dst,$src); | |
1037 | push @opcode,0x0f,0x3a,0x22; | |
1038 | push @opcode,0xc0|(($dst&7)<<3)|($src&7); # ModR/M | |
1039 | push @opcode,$imm; | |
a9e790b9 | 1040 | @opcode; |
fead2539 | 1041 | } else { |
a9e790b9 | 1042 | (); |
fead2539 | 1043 | } |
a9e790b9 | 1044 | }; |
fead2539 AP |
1045 | |
1046 | my $pshufb = sub { | |
a87ff751 | 1047 | if (shift =~ /%xmm([0-9]+),\s*%xmm([0-9]+)/) { |
fead2539 | 1048 | my @opcode=(0x66); |
a9e790b9 | 1049 | rex(\@opcode,$2,$1); |
fead2539 | 1050 | push @opcode,0x0f,0x38,0x00; |
a9e790b9 AP |
1051 | push @opcode,0xc0|($1&7)|(($2&7)<<3); # ModR/M |
1052 | @opcode; | |
fead2539 | 1053 | } else { |
a9e790b9 | 1054 | (); |
fead2539 | 1055 | } |
a9e790b9 | 1056 | }; |
fead2539 | 1057 | |
b5c6aab5 | 1058 | my $palignr = sub { |
a87ff751 | 1059 | if (shift =~ /\$([0-9]+),\s*%xmm([0-9]+),\s*%xmm([0-9]+)/) { |
b5c6aab5 AP |
1060 | my @opcode=(0x66); |
1061 | rex(\@opcode,$3,$2); | |
1062 | push @opcode,0x0f,0x3a,0x0f; | |
1063 | push @opcode,0xc0|($2&7)|(($3&7)<<3); # ModR/M | |
1064 | push @opcode,$1; | |
1065 | @opcode; | |
1066 | } else { | |
1067 | (); | |
1068 | } | |
1069 | }; | |
1070 | ||
1071 | my $pclmulqdq = sub { | |
1072 | if (shift =~ /\$([x0-9a-f]+),\s*%xmm([0-9]+),\s*%xmm([0-9]+)/) { | |
1073 | my @opcode=(0x66); | |
1074 | rex(\@opcode,$3,$2); | |
1075 | push @opcode,0x0f,0x3a,0x44; | |
1076 | push @opcode,0xc0|($2&7)|(($3&7)<<3); # ModR/M | |
1077 | my $c=$1; | |
1078 | push @opcode,$c=~/^0/?oct($c):$c; | |
1079 | @opcode; | |
1080 | } else { | |
1081 | (); | |
1082 | } | |
1083 | }; | |
1084 | ||
301799b8 AP |
1085 | my $rdrand = sub { |
1086 | if (shift =~ /%[er](\w+)/) { | |
1087 | my @opcode=(); | |
1088 | my $dst=$1; | |
1089 | if ($dst !~ /[0-9]+/) { $dst = $regrm{"%e$dst"}; } | |
9c940446 | 1090 | rex(\@opcode,0,$dst,8); |
301799b8 AP |
1091 | push @opcode,0x0f,0xc7,0xf0|($dst&7); |
1092 | @opcode; | |
1093 | } else { | |
1094 | (); | |
1095 | } | |
1096 | }; | |
1097 | ||
f4d45640 AP |
1098 | my $rdseed = sub { |
1099 | if (shift =~ /%[er](\w+)/) { | |
1100 | my @opcode=(); | |
1101 | my $dst=$1; | |
1102 | if ($dst !~ /[0-9]+/) { $dst = $regrm{"%e$dst"}; } | |
9c940446 | 1103 | rex(\@opcode,0,$dst,8); |
f4d45640 AP |
1104 | push @opcode,0x0f,0xc7,0xf8|($dst&7); |
1105 | @opcode; | |
1106 | } else { | |
1107 | (); | |
1108 | } | |
1109 | }; | |
1110 | ||
e09b6216 AP |
1111 | # Not all AVX-capable assemblers recognize AMD XOP extension. Since we |
1112 | # are using only two instructions hand-code them in order to be excused | |
1113 | # from chasing assembler versions... | |
1114 | ||
f6ff1aa8 | 1115 | sub rxb { |
c25278db | 1116 | my $opcode=shift; |
f6ff1aa8 AP |
1117 | my ($dst,$src1,$src2,$rxb)=@_; |
1118 | ||
1119 | $rxb|=0x7<<5; | |
1120 | $rxb&=~(0x04<<5) if($dst>=8); | |
1121 | $rxb&=~(0x01<<5) if($src1>=8); | |
1122 | $rxb&=~(0x02<<5) if($src2>=8); | |
c25278db | 1123 | push @$opcode,$rxb; |
f6ff1aa8 AP |
1124 | } |
1125 | ||
1126 | my $vprotd = sub { | |
1127 | if (shift =~ /\$([x0-9a-f]+),\s*%xmm([0-9]+),\s*%xmm([0-9]+)/) { | |
1128 | my @opcode=(0x8f); | |
1129 | rxb(\@opcode,$3,$2,-1,0x08); | |
1130 | push @opcode,0x78,0xc2; | |
1131 | push @opcode,0xc0|($2&7)|(($3&7)<<3); # ModR/M | |
1132 | my $c=$1; | |
1133 | push @opcode,$c=~/^0/?oct($c):$c; | |
1134 | @opcode; | |
1135 | } else { | |
1136 | (); | |
1137 | } | |
1138 | }; | |
1139 | ||
1140 | my $vprotq = sub { | |
1141 | if (shift =~ /\$([x0-9a-f]+),\s*%xmm([0-9]+),\s*%xmm([0-9]+)/) { | |
1142 | my @opcode=(0x8f); | |
1143 | rxb(\@opcode,$3,$2,-1,0x08); | |
1144 | push @opcode,0x78,0xc3; | |
1145 | push @opcode,0xc0|($2&7)|(($3&7)<<3); # ModR/M | |
1146 | my $c=$1; | |
1147 | push @opcode,$c=~/^0/?oct($c):$c; | |
1148 | @opcode; | |
1149 | } else { | |
1150 | (); | |
1151 | } | |
1152 | }; | |
1153 | ||
e09b6216 AP |
1154 | # Intel Control-flow Enforcement Technology extension. All functions and |
1155 | # indirect branch targets will have to start with this instruction... | |
1156 | ||
4e3d2866 AP |
1157 | my $endbranch = sub { |
1158 | (0xf3,0x0f,0x1e,0xfa); | |
1159 | }; | |
1160 | ||
e09b6216 AP |
1161 | ######################################################################## |
1162 | ||
9b634c9b AP |
1163 | if ($nasm) { |
1164 | print <<___; | |
1165 | default rel | |
a9e790b9 | 1166 | %define XMMWORD |
1b0fe79f AP |
1167 | %define YMMWORD |
1168 | %define ZMMWORD | |
9b634c9b AP |
1169 | ___ |
1170 | } elsif ($masm) { | |
1171 | print <<___; | |
1172 | OPTION DOTNAME | |
1173 | ___ | |
1174 | } | |
c25278db | 1175 | while(defined(my $line=<>)) { |
1cfd258e | 1176 | |
9ba96fbb | 1177 | $line =~ s|\R$||; # Better chomp |
1cfd258e | 1178 | |
4b450519 AP |
1179 | $line =~ s|[#!].*$||; # get rid of asm-style comments... |
1180 | $line =~ s|/\*.*\*/||; # ... and C-style comments... | |
1181 | $line =~ s|^\s+||; # ... and skip white spaces in beginning | |
41965a84 | 1182 | $line =~ s|\s+$||; # ... and at the end |
1cfd258e | 1183 | |
c25278db | 1184 | if (my $label=label->re(\$line)) { print $label->out(); } |
1cfd258e | 1185 | |
c25278db DB |
1186 | if (my $directive=directive->re(\$line)) { |
1187 | printf "%s",$directive->out(); | |
1188 | } elsif (my $opcode=opcode->re(\$line)) { | |
a9e790b9 | 1189 | my $asm = eval("\$".$opcode->mnemonic()); |
609b0852 | 1190 | |
c25278db | 1191 | if ((ref($asm) eq 'CODE') && scalar(my @bytes=&$asm($line))) { |
a9e790b9 AP |
1192 | print $gas?".byte\t":"DB\t",join(',',@bytes),"\n"; |
1193 | next; | |
1194 | } | |
1195 | ||
c25278db | 1196 | my @args; |
a9e790b9 | 1197 | ARGUMENT: while (1) { |
6a4ea002 | 1198 | my $arg; |
1cfd258e | 1199 | |
6a4ea002 AP |
1200 | ($arg=register->re(\$line, $opcode))|| |
1201 | ($arg=const->re(\$line)) || | |
1202 | ($arg=ea->re(\$line, $opcode)) || | |
1203 | ($arg=expr->re(\$line, $opcode)) || | |
1204 | last ARGUMENT; | |
1cfd258e | 1205 | |
6a4ea002 | 1206 | push @args,$arg; |
1cfd258e | 1207 | |
6a4ea002 | 1208 | last ARGUMENT if ($line !~ /^,/); |
1cfd258e | 1209 | |
6a4ea002 | 1210 | $line =~ s/^,\s*//; |
1cfd258e AP |
1211 | } # ARGUMENT: |
1212 | ||
4db48824 AP |
1213 | if ($#args>=0) { |
1214 | my $insn; | |
c25278db | 1215 | my $sz=$opcode->size(); |
a9e790b9 | 1216 | |
85253772 | 1217 | if ($gas) { |
4db48824 | 1218 | $insn = $opcode->out($#args>=1?$args[$#args]->size():$sz); |
fead2539 | 1219 | @args = map($_->out($sz),@args); |
a9e790b9 | 1220 | printf "\t%s\t%s",$insn,join(",",@args); |
5d0d60e2 | 1221 | } else { |
4db48824 | 1222 | $insn = $opcode->out(); |
046ea308 AP |
1223 | foreach (@args) { |
1224 | my $arg = $_->out(); | |
a9e790b9 AP |
1225 | # $insn.=$sz compensates for movq, pinsrw, ... |
1226 | if ($arg =~ /^xmm[0-9]+$/) { $insn.=$sz; $sz="x" if(!$sz); last; } | |
a9d14832 | 1227 | if ($arg =~ /^ymm[0-9]+$/) { $insn.=$sz; $sz="y" if(!$sz); last; } |
1b0fe79f | 1228 | if ($arg =~ /^zmm[0-9]+$/) { $insn.=$sz; $sz="z" if(!$sz); last; } |
a9e790b9 | 1229 | if ($arg =~ /^mm[0-9]+$/) { $insn.=$sz; $sz="q" if(!$sz); last; } |
046ea308 | 1230 | } |
4db48824 | 1231 | @args = reverse(@args); |
a23e3dbe | 1232 | undef $sz if ($nasm && $opcode->mnemonic() eq "lea"); |
fead2539 | 1233 | printf "\t%s\t%s",$insn,join(",",map($_->out($sz),@args)); |
1cfd258e | 1234 | } |
1cfd258e AP |
1235 | } else { |
1236 | printf "\t%s",$opcode->out(); | |
1237 | } | |
1238 | } | |
1239 | ||
1240 | print $line,"\n"; | |
1241 | } | |
1242 | ||
51994e50 | 1243 | print "$cet_property" if ($cet_property); |
85253772 AP |
1244 | print "\n$current_segment\tENDS\n" if ($current_segment && $masm); |
1245 | print "END\n" if ($masm); | |
1cfd258e | 1246 | |
a21314db | 1247 | close STDOUT or die "error closing STDOUT: $!;" |
1cfd258e | 1248 | |
80aa9cc9 | 1249 | \f################################################# |
1cfd258e AP |
1250 | # Cross-reference x86_64 ABI "card" |
1251 | # | |
1252 | # Unix Win64 | |
1253 | # %rax * * | |
1254 | # %rbx - - | |
1255 | # %rcx #4 #1 | |
1256 | # %rdx #3 #2 | |
1257 | # %rsi #2 - | |
1258 | # %rdi #1 - | |
1259 | # %rbp - - | |
1260 | # %rsp - - | |
1261 | # %r8 #5 #3 | |
1262 | # %r9 #6 #4 | |
1263 | # %r10 * * | |
1264 | # %r11 * * | |
1265 | # %r12 - - | |
1266 | # %r13 - - | |
1267 | # %r14 - - | |
1268 | # %r15 - - | |
609b0852 | 1269 | # |
1cfd258e AP |
1270 | # (*) volatile register |
1271 | # (-) preserved by callee | |
1272 | # (#) Nth argument, volatile | |
1273 | # | |
1274 | # In Unix terms top of stack is argument transfer area for arguments | |
0d4fb843 | 1275 | # which could not be accommodated in registers. Or in other words 7th |
1cfd258e AP |
1276 | # [integer] argument resides at 8(%rsp) upon function entry point. |
1277 | # 128 bytes above %rsp constitute a "red zone" which is not touched | |
1278 | # by signal handlers and can be used as temporal storage without | |
1279 | # allocating a frame. | |
1280 | # | |
1281 | # In Win64 terms N*8 bytes on top of stack is argument transfer area, | |
1282 | # which belongs to/can be overwritten by callee. N is the number of | |
1283 | # arguments passed to callee, *but* not less than 4! This means that | |
1284 | # upon function entry point 5th argument resides at 40(%rsp), as well | |
1285 | # as that 32 bytes from 8(%rsp) can always be used as temporal | |
d256b957 AP |
1286 | # storage [without allocating a frame]. One can actually argue that |
1287 | # one can assume a "red zone" above stack pointer under Win64 as well. | |
6a3a7f30 AP |
1288 | # Point is that at apparently no occasion Windows kernel would alter |
1289 | # the area above user stack pointer in true asynchronous manner... | |
1cfd258e AP |
1290 | # |
1291 | # All the above means that if assembler programmer adheres to Unix | |
7e12cdb5 | 1292 | # register and stack layout, but disregards the "red zone" existence, |
1cfd258e AP |
1293 | # it's possible to use following prologue and epilogue to "gear" from |
1294 | # Unix to Win64 ABI in leaf functions with not more than 6 arguments. | |
1295 | # | |
1296 | # omnipotent_function: | |
1297 | # ifdef WIN64 | |
1298 | # movq %rdi,8(%rsp) | |
1299 | # movq %rsi,16(%rsp) | |
1300 | # movq %rcx,%rdi ; if 1st argument is actually present | |
1301 | # movq %rdx,%rsi ; if 2nd argument is actually ... | |
1302 | # movq %r8,%rdx ; if 3rd argument is ... | |
1303 | # movq %r9,%rcx ; if 4th argument ... | |
1304 | # movq 40(%rsp),%r8 ; if 5th ... | |
1305 | # movq 48(%rsp),%r9 ; if 6th ... | |
1306 | # endif | |
1307 | # ... | |
1308 | # ifdef WIN64 | |
1309 | # movq 8(%rsp),%rdi | |
1310 | # movq 16(%rsp),%rsi | |
1311 | # endif | |
1312 | # ret | |
4f469342 | 1313 | # |
80aa9cc9 AP |
1314 | \f################################################# |
1315 | # Win64 SEH, Structured Exception Handling. | |
1316 | # | |
4f469342 AP |
1317 | # Unlike on Unix systems(*) lack of Win64 stack unwinding information |
1318 | # has undesired side-effect at run-time: if an exception is raised in | |
1319 | # assembler subroutine such as those in question (basically we're | |
1320 | # referring to segmentation violations caused by malformed input | |
1321 | # parameters), the application is briskly terminated without invoking | |
1322 | # any exception handlers, most notably without generating memory dump | |
1323 | # or any user notification whatsoever. This poses a problem. It's | |
1324 | # possible to address it by registering custom language-specific | |
1325 | # handler that would restore processor context to the state at | |
1326 | # subroutine entry point and return "exception is not handled, keep | |
1327 | # unwinding" code. Writing such handler can be a challenge... But it's | |
1328 | # doable, though requires certain coding convention. Consider following | |
1329 | # snippet: | |
1330 | # | |
80aa9cc9 | 1331 | # .type function,@function |
4f469342 AP |
1332 | # function: |
1333 | # movq %rsp,%rax # copy rsp to volatile register | |
1334 | # pushq %r15 # save non-volatile registers | |
1335 | # pushq %rbx | |
1336 | # pushq %rbp | |
1337 | # movq %rsp,%r11 | |
1338 | # subq %rdi,%r11 # prepare [variable] stack frame | |
1339 | # andq $-64,%r11 | |
1340 | # movq %rax,0(%r11) # check for exceptions | |
1341 | # movq %r11,%rsp # allocate [variable] stack frame | |
1342 | # movq %rax,0(%rsp) # save original rsp value | |
1343 | # magic_point: | |
1344 | # ... | |
1345 | # movq 0(%rsp),%rcx # pull original rsp value | |
1346 | # movq -24(%rcx),%rbp # restore non-volatile registers | |
1347 | # movq -16(%rcx),%rbx | |
1348 | # movq -8(%rcx),%r15 | |
1349 | # movq %rcx,%rsp # restore original rsp | |
e1dbf7f4 | 1350 | # magic_epilogue: |
4f469342 | 1351 | # ret |
80aa9cc9 | 1352 | # .size function,.-function |
4f469342 AP |
1353 | # |
1354 | # The key is that up to magic_point copy of original rsp value remains | |
1355 | # in chosen volatile register and no non-volatile register, except for | |
1356 | # rsp, is modified. While past magic_point rsp remains constant till | |
1357 | # the very end of the function. In this case custom language-specific | |
1358 | # exception handler would look like this: | |
1359 | # | |
1360 | # EXCEPTION_DISPOSITION handler (EXCEPTION_RECORD *rec,ULONG64 frame, | |
1361 | # CONTEXT *context,DISPATCHER_CONTEXT *disp) | |
80aa9cc9 | 1362 | # { ULONG64 *rsp = (ULONG64 *)context->Rax; |
e1dbf7f4 AP |
1363 | # ULONG64 rip = context->Rip; |
1364 | # | |
1365 | # if (rip >= magic_point) | |
1366 | # { rsp = (ULONG64 *)context->Rsp; | |
1367 | # if (rip < magic_epilogue) | |
1368 | # { rsp = (ULONG64 *)rsp[0]; | |
1369 | # context->Rbp = rsp[-3]; | |
1370 | # context->Rbx = rsp[-2]; | |
1371 | # context->R15 = rsp[-1]; | |
1372 | # } | |
4f469342 AP |
1373 | # } |
1374 | # context->Rsp = (ULONG64)rsp; | |
1375 | # context->Rdi = rsp[1]; | |
1376 | # context->Rsi = rsp[2]; | |
1377 | # | |
1378 | # memcpy (disp->ContextRecord,context,sizeof(CONTEXT)); | |
1379 | # RtlVirtualUnwind(UNW_FLAG_NHANDLER,disp->ImageBase, | |
1380 | # dips->ControlPc,disp->FunctionEntry,disp->ContextRecord, | |
1381 | # &disp->HandlerData,&disp->EstablisherFrame,NULL); | |
1382 | # return ExceptionContinueSearch; | |
1383 | # } | |
1384 | # | |
1385 | # It's appropriate to implement this handler in assembler, directly in | |
1386 | # function's module. In order to do that one has to know members' | |
1387 | # offsets in CONTEXT and DISPATCHER_CONTEXT structures and some constant | |
1388 | # values. Here they are: | |
1389 | # | |
1390 | # CONTEXT.Rax 120 | |
1391 | # CONTEXT.Rcx 128 | |
1392 | # CONTEXT.Rdx 136 | |
1393 | # CONTEXT.Rbx 144 | |
1394 | # CONTEXT.Rsp 152 | |
1395 | # CONTEXT.Rbp 160 | |
1396 | # CONTEXT.Rsi 168 | |
1397 | # CONTEXT.Rdi 176 | |
1398 | # CONTEXT.R8 184 | |
1399 | # CONTEXT.R9 192 | |
1400 | # CONTEXT.R10 200 | |
1401 | # CONTEXT.R11 208 | |
1402 | # CONTEXT.R12 216 | |
1403 | # CONTEXT.R13 224 | |
1404 | # CONTEXT.R14 232 | |
1405 | # CONTEXT.R15 240 | |
1406 | # CONTEXT.Rip 248 | |
6dd9066e | 1407 | # CONTEXT.Xmm6 512 |
4f469342 AP |
1408 | # sizeof(CONTEXT) 1232 |
1409 | # DISPATCHER_CONTEXT.ControlPc 0 | |
1410 | # DISPATCHER_CONTEXT.ImageBase 8 | |
1411 | # DISPATCHER_CONTEXT.FunctionEntry 16 | |
1412 | # DISPATCHER_CONTEXT.EstablisherFrame 24 | |
1413 | # DISPATCHER_CONTEXT.TargetIp 32 | |
1414 | # DISPATCHER_CONTEXT.ContextRecord 40 | |
1415 | # DISPATCHER_CONTEXT.LanguageHandler 48 | |
1416 | # DISPATCHER_CONTEXT.HandlerData 56 | |
1417 | # UNW_FLAG_NHANDLER 0 | |
1418 | # ExceptionContinueSearch 1 | |
1419 | # | |
80aa9cc9 AP |
1420 | # In order to tie the handler to the function one has to compose |
1421 | # couple of structures: one for .xdata segment and one for .pdata. | |
1422 | # | |
4f469342 | 1423 | # UNWIND_INFO structure for .xdata segment would be |
80aa9cc9 AP |
1424 | # |
1425 | # function_unwind_info: | |
1426 | # .byte 9,0,0,0 | |
85253772 | 1427 | # .rva handler |
80aa9cc9 AP |
1428 | # |
1429 | # This structure designates exception handler for a function with | |
1430 | # zero-length prologue, no stack frame or frame register. | |
1431 | # | |
1432 | # To facilitate composing of .pdata structures, auto-generated "gear" | |
1433 | # prologue copies rsp value to rax and denotes next instruction with | |
85253772 | 1434 | # .LSEH_begin_{function_name} label. This essentially defines the SEH |
80aa9cc9 AP |
1435 | # styling rule mentioned in the beginning. Position of this label is |
1436 | # chosen in such manner that possible exceptions raised in the "gear" | |
1437 | # prologue would be accounted to caller and unwound from latter's frame. | |
85253772 | 1438 | # End of function is marked with respective .LSEH_end_{function_name} |
80aa9cc9 AP |
1439 | # label. To summarize, .pdata segment would contain |
1440 | # | |
85253772 AP |
1441 | # .rva .LSEH_begin_function |
1442 | # .rva .LSEH_end_function | |
1443 | # .rva function_unwind_info | |
80aa9cc9 | 1444 | # |
478b50cf | 1445 | # Reference to function_unwind_info from .xdata segment is the anchor. |
85253772 | 1446 | # In case you wonder why references are 32-bit .rvas and not 64-bit |
80aa9cc9 AP |
1447 | # .quads. References put into these two segments are required to be |
1448 | # *relative* to the base address of the current binary module, a.k.a. | |
1449 | # image base. No Win64 module, be it .exe or .dll, can be larger than | |
1450 | # 2GB and thus such relative references can be and are accommodated in | |
1451 | # 32 bits. | |
1452 | # | |
1453 | # Having reviewed the example function code, one can argue that "movq | |
1454 | # %rsp,%rax" above is redundant. It is not! Keep in mind that on Unix | |
1455 | # rax would contain an undefined value. If this "offends" you, use | |
1456 | # another register and refrain from modifying rax till magic_point is | |
1457 | # reached, i.e. as if it was a non-volatile register. If more registers | |
1458 | # are required prior [variable] frame setup is completed, note that | |
1459 | # nobody says that you can have only one "magic point." You can | |
1460 | # "liberate" non-volatile registers by denoting last stack off-load | |
1461 | # instruction and reflecting it in finer grade unwind logic in handler. | |
1462 | # After all, isn't it why it's called *language-specific* handler... | |
1463 | # | |
e1dbf7f4 AP |
1464 | # SE handlers are also involved in unwinding stack when executable is |
1465 | # profiled or debugged. Profiling implies additional limitations that | |
1466 | # are too subtle to discuss here. For now it's sufficient to say that | |
1467 | # in order to simplify handlers one should either a) offload original | |
1468 | # %rsp to stack (like discussed above); or b) if you have a register to | |
1469 | # spare for frame pointer, choose volatile one. | |
4f469342 AP |
1470 | # |
1471 | # (*) Note that we're talking about run-time, not debug-time. Lack of | |
1472 | # unwind information makes debugging hard on both Windows and | |
46f4e1be | 1473 | # Unix. "Unlike" refers to the fact that on Unix signal handler |
4f469342 AP |
1474 | # will always be invoked, core dumped and appropriate exit code |
1475 | # returned to parent (for user notification). |