David Benjamin | c895d6b | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 1 | #! /usr/bin/env perl |
| 2 | # Copyright 2005-2016 The OpenSSL Project Authors. All Rights Reserved. |
| 3 | # |
| 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 |
| 8 | |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 9 | |
| 10 | # Ascetic x86_64 AT&T to MASM/NASM assembler translator by <appro>. |
| 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; |
| 30 | # |
| 31 | # Dual-ABI styling rules. |
| 32 | # |
| 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 |
Robert Sloan | 5d62578 | 2017-02-13 09:55:39 -0800 | [diff] [blame] | 54 | # modes. |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 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. |
| 59 | # 9. .init segment is allowed to contain calls to functions only. |
| 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. |
| 62 | |
David Benjamin | c895d6b | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 63 | |
| 64 | use strict; |
| 65 | |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 66 | my $flavour = shift; |
| 67 | my $output = shift; |
| 68 | if ($flavour =~ /\./) { $output = $flavour; undef $flavour; } |
| 69 | |
| 70 | open STDOUT,">$output" || die "can't open $output: $!" |
| 71 | if (defined($output)); |
| 72 | |
| 73 | my $gas=1; $gas=0 if ($output =~ /\.asm$/); |
| 74 | my $elf=1; $elf=0 if (!$gas); |
| 75 | my $win64=0; |
| 76 | my $prefix=""; |
| 77 | my $decor=".L"; |
| 78 | |
| 79 | my $masmref=8 + 50727*2**-32; # 8.00.50727 shipped with VS2005 |
| 80 | my $masm=0; |
| 81 | my $PTR=" PTR"; |
| 82 | |
| 83 | my $nasmref=2.03; |
| 84 | my $nasm=0; |
| 85 | |
| 86 | if ($flavour eq "mingw64") { $gas=1; $elf=0; $win64=1; |
Kenny Root | e99801b | 2015-11-06 15:31:15 -0800 | [diff] [blame] | 87 | # TODO(davidben): Before supporting the |
| 88 | # mingw64 perlasm flavour, do away with this |
| 89 | # environment variable check. |
| 90 | die "mingw64 not supported"; |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 91 | $prefix=`echo __USER_LABEL_PREFIX__ | $ENV{CC} -E -P -`; |
David Benjamin | c895d6b | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 92 | $prefix =~ s|\R$||; # Better chomp |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 93 | } |
| 94 | elsif ($flavour eq "macosx") { $gas=1; $elf=0; $prefix="_"; $decor="L\$"; } |
| 95 | elsif ($flavour eq "masm") { $gas=0; $elf=0; $masm=$masmref; $win64=1; $decor="\$L\$"; } |
| 96 | elsif ($flavour eq "nasm") { $gas=0; $elf=0; $nasm=$nasmref; $win64=1; $decor="\$L\$"; $PTR=""; } |
David Benjamin | c895d6b | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 97 | elsif (!$gas) { die "unknown flavour $flavour"; } |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 98 | |
| 99 | my $current_segment; |
| 100 | my $current_function; |
| 101 | my %globals; |
| 102 | |
| 103 | { package opcode; # pick up opcodes |
| 104 | sub re { |
David Benjamin | c895d6b | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 105 | my ($class, $line) = @_; |
| 106 | my $self = {}; |
| 107 | my $ret; |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 108 | |
David Benjamin | c895d6b | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 109 | if ($$line =~ /^([a-z][a-z0-9]*)/i) { |
| 110 | bless $self,$class; |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 111 | $self->{op} = $1; |
| 112 | $ret = $self; |
David Benjamin | c895d6b | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 113 | $$line = substr($$line,@+[0]); $$line =~ s/^\s+//; |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 114 | |
| 115 | undef $self->{sz}; |
| 116 | if ($self->{op} =~ /^(movz)x?([bw]).*/) { # movz is pain... |
| 117 | $self->{op} = $1; |
| 118 | $self->{sz} = $2; |
| 119 | } elsif ($self->{op} =~ /call|jmp/) { |
| 120 | $self->{sz} = ""; |
| 121 | } elsif ($self->{op} =~ /^p/ && $' !~ /^(ush|op|insrw)/) { # SSEn |
| 122 | $self->{sz} = ""; |
Robert Sloan | 5d62578 | 2017-02-13 09:55:39 -0800 | [diff] [blame] | 123 | } elsif ($self->{op} =~ /^[vk]/) { # VEX or k* such as kmov |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 124 | $self->{sz} = ""; |
David Benjamin | c895d6b | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 125 | } elsif ($self->{op} =~ /mov[dq]/ && $$line =~ /%xmm/) { |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 126 | $self->{sz} = ""; |
| 127 | } elsif ($self->{op} =~ /([a-z]{3,})([qlwb])$/) { |
| 128 | $self->{op} = $1; |
| 129 | $self->{sz} = $2; |
| 130 | } |
| 131 | } |
| 132 | $ret; |
| 133 | } |
| 134 | sub size { |
David Benjamin | c895d6b | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 135 | my ($self, $sz) = @_; |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 136 | $self->{sz} = $sz if (defined($sz) && !defined($self->{sz})); |
| 137 | $self->{sz}; |
| 138 | } |
| 139 | sub out { |
| 140 | my $self = shift; |
| 141 | if ($gas) { |
| 142 | if ($self->{op} eq "movz") { # movz is pain... |
| 143 | sprintf "%s%s%s",$self->{op},$self->{sz},shift; |
Robert Sloan | a94fe05 | 2017-02-21 08:49:28 -0800 | [diff] [blame] | 144 | } elsif ($self->{op} =~ /^set/) { |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 145 | "$self->{op}"; |
| 146 | } elsif ($self->{op} eq "ret") { |
| 147 | my $epilogue = ""; |
| 148 | if ($win64 && $current_function->{abi} eq "svr4") { |
| 149 | $epilogue = "movq 8(%rsp),%rdi\n\t" . |
| 150 | "movq 16(%rsp),%rsi\n\t"; |
| 151 | } |
| 152 | $epilogue . ".byte 0xf3,0xc3"; |
| 153 | } elsif ($self->{op} eq "call" && !$elf && $current_segment eq ".init") { |
| 154 | ".p2align\t3\n\t.quad"; |
| 155 | } else { |
| 156 | "$self->{op}$self->{sz}"; |
| 157 | } |
| 158 | } else { |
| 159 | $self->{op} =~ s/^movz/movzx/; |
| 160 | if ($self->{op} eq "ret") { |
| 161 | $self->{op} = ""; |
| 162 | if ($win64 && $current_function->{abi} eq "svr4") { |
David Benjamin | c895d6b | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 163 | $self->{op} = "mov rdi,QWORD$PTR\[8+rsp\]\t;WIN64 epilogue\n\t". |
| 164 | "mov rsi,QWORD$PTR\[16+rsp\]\n\t"; |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 165 | } |
| 166 | $self->{op} .= "DB\t0F3h,0C3h\t\t;repret"; |
| 167 | } elsif ($self->{op} =~ /^(pop|push)f/) { |
| 168 | $self->{op} .= $self->{sz}; |
| 169 | } elsif ($self->{op} eq "call" && $current_segment eq ".CRT\$XCU") { |
| 170 | $self->{op} = "\tDQ"; |
Robert Sloan | a94fe05 | 2017-02-21 08:49:28 -0800 | [diff] [blame] | 171 | } |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 172 | $self->{op}; |
| 173 | } |
| 174 | } |
| 175 | sub mnemonic { |
David Benjamin | c895d6b | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 176 | my ($self, $op) = @_; |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 177 | $self->{op}=$op if (defined($op)); |
| 178 | $self->{op}; |
| 179 | } |
| 180 | } |
| 181 | { package const; # pick up constants, which start with $ |
| 182 | sub re { |
David Benjamin | c895d6b | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 183 | my ($class, $line) = @_; |
| 184 | my $self = {}; |
| 185 | my $ret; |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 186 | |
David Benjamin | c895d6b | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 187 | if ($$line =~ /^\$([^,]+)/) { |
| 188 | bless $self, $class; |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 189 | $self->{value} = $1; |
| 190 | $ret = $self; |
David Benjamin | c895d6b | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 191 | $$line = substr($$line,@+[0]); $$line =~ s/^\s+//; |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 192 | } |
| 193 | $ret; |
| 194 | } |
| 195 | sub out { |
| 196 | my $self = shift; |
| 197 | |
David Benjamin | 4969cc9 | 2016-04-22 15:02:23 -0400 | [diff] [blame] | 198 | $self->{value} =~ s/\b(0b[0-1]+)/oct($1)/eig; |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 199 | if ($gas) { |
| 200 | # Solaris /usr/ccs/bin/as can't handle multiplications |
| 201 | # in $self->{value} |
David Benjamin | 4969cc9 | 2016-04-22 15:02:23 -0400 | [diff] [blame] | 202 | my $value = $self->{value}; |
David Benjamin | c895d6b | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 203 | no warnings; # oct might complain about overflow, ignore here... |
David Benjamin | 4969cc9 | 2016-04-22 15:02:23 -0400 | [diff] [blame] | 204 | $value =~ s/(?<![\w\$\.])(0x?[0-9a-f]+)/oct($1)/egi; |
| 205 | if ($value =~ s/([0-9]+\s*[\*\/\%]\s*[0-9]+)/eval($1)/eg) { |
David Benjamin | c895d6b | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 206 | $self->{value} = $value; |
David Benjamin | 4969cc9 | 2016-04-22 15:02:23 -0400 | [diff] [blame] | 207 | } |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 208 | sprintf "\$%s",$self->{value}; |
| 209 | } else { |
Robert Sloan | 8ff0355 | 2017-06-14 12:40:58 -0700 | [diff] [blame] | 210 | my $value = $self->{value}; |
| 211 | $value =~ s/0x([0-9a-f]+)/0$1h/ig if ($masm); |
| 212 | sprintf "%s",$value; |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 213 | } |
| 214 | } |
| 215 | } |
| 216 | { package ea; # pick up effective addresses: expr(%reg,%reg,scale) |
Robert Sloan | 5d62578 | 2017-02-13 09:55:39 -0800 | [diff] [blame] | 217 | |
| 218 | my %szmap = ( b=>"BYTE$PTR", w=>"WORD$PTR", |
| 219 | l=>"DWORD$PTR", d=>"DWORD$PTR", |
| 220 | q=>"QWORD$PTR", o=>"OWORD$PTR", |
| 221 | x=>"XMMWORD$PTR", y=>"YMMWORD$PTR", |
| 222 | z=>"ZMMWORD$PTR" ) if (!$gas); |
| 223 | |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 224 | sub re { |
David Benjamin | c895d6b | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 225 | my ($class, $line, $opcode) = @_; |
| 226 | my $self = {}; |
| 227 | my $ret; |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 228 | |
David Benjamin | c895d6b | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 229 | # optional * ----vvv--- appears in indirect jmp/call |
Robert Sloan | 5d62578 | 2017-02-13 09:55:39 -0800 | [diff] [blame] | 230 | if ($$line =~ /^(\*?)([^\(,]*)\(([%\w,]+)\)((?:{[^}]+})*)/) { |
David Benjamin | c895d6b | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 231 | bless $self, $class; |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 232 | $self->{asterisk} = $1; |
| 233 | $self->{label} = $2; |
| 234 | ($self->{base},$self->{index},$self->{scale})=split(/,/,$3); |
| 235 | $self->{scale} = 1 if (!defined($self->{scale})); |
Robert Sloan | 5d62578 | 2017-02-13 09:55:39 -0800 | [diff] [blame] | 236 | $self->{opmask} = $4; |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 237 | $ret = $self; |
David Benjamin | c895d6b | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 238 | $$line = substr($$line,@+[0]); $$line =~ s/^\s+//; |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 239 | |
| 240 | if ($win64 && $self->{label} =~ s/\@GOTPCREL//) { |
David Benjamin | c895d6b | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 241 | die if ($opcode->mnemonic() ne "mov"); |
| 242 | $opcode->mnemonic("lea"); |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 243 | } |
| 244 | $self->{base} =~ s/^%//; |
| 245 | $self->{index} =~ s/^%// if (defined($self->{index})); |
David Benjamin | c895d6b | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 246 | $self->{opcode} = $opcode; |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 247 | } |
| 248 | $ret; |
| 249 | } |
| 250 | sub size {} |
| 251 | sub out { |
David Benjamin | c895d6b | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 252 | my ($self, $sz) = @_; |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 253 | |
| 254 | $self->{label} =~ s/([_a-z][_a-z0-9]*)/$globals{$1} or $1/gei; |
| 255 | $self->{label} =~ s/\.L/$decor/g; |
| 256 | |
| 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/; |
| 262 | |
| 263 | # Solaris /usr/ccs/bin/as can't handle multiplications |
Steven Valdez | e7531f0 | 2016-12-14 13:29:57 -0500 | [diff] [blame] | 264 | # in $self->{label}... |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 265 | use integer; |
| 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; |
Steven Valdez | e7531f0 | 2016-12-14 13:29:57 -0500 | [diff] [blame] | 268 | |
| 269 | # Some assemblers insist on signed presentation of 32-bit |
| 270 | # offsets, but sign extension is a tricky business in perl... |
| 271 | if ((1<<31)<<1) { |
| 272 | $self->{label} =~ s/\b([0-9]+)\b/$1<<32>>32/eg; |
| 273 | } else { |
| 274 | $self->{label} =~ s/\b([0-9]+)\b/$1>>0/eg; |
| 275 | } |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 276 | |
Robert Sloan | 5d62578 | 2017-02-13 09:55:39 -0800 | [diff] [blame] | 277 | # if base register is %rbp or %r13, see if it's possible to |
Robert Sloan | a94fe05 | 2017-02-21 08:49:28 -0800 | [diff] [blame] | 278 | # flip base and index registers [for better performance] |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 279 | if (!$self->{label} && $self->{index} && $self->{scale}==1 && |
| 280 | $self->{base} =~ /(rbp|r13)/) { |
| 281 | $self->{base} = $self->{index}; $self->{index} = $1; |
| 282 | } |
| 283 | |
| 284 | if ($gas) { |
| 285 | $self->{label} =~ s/^___imp_/__imp__/ if ($flavour eq "mingw64"); |
| 286 | |
| 287 | if (defined($self->{index})) { |
Robert Sloan | 5d62578 | 2017-02-13 09:55:39 -0800 | [diff] [blame] | 288 | sprintf "%s%s(%s,%%%s,%d)%s", |
| 289 | $self->{asterisk},$self->{label}, |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 290 | $self->{base}?"%$self->{base}":"", |
Robert Sloan | 5d62578 | 2017-02-13 09:55:39 -0800 | [diff] [blame] | 291 | $self->{index},$self->{scale}, |
| 292 | $self->{opmask}; |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 293 | } else { |
Robert Sloan | 5d62578 | 2017-02-13 09:55:39 -0800 | [diff] [blame] | 294 | sprintf "%s%s(%%%s)%s", $self->{asterisk},$self->{label}, |
| 295 | $self->{base},$self->{opmask}; |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 296 | } |
| 297 | } else { |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 298 | $self->{label} =~ s/\./\$/g; |
| 299 | $self->{label} =~ s/(?<![\w\$\.])0x([0-9a-f]+)/0$1h/ig; |
| 300 | $self->{label} = "($self->{label})" if ($self->{label} =~ /[\*\+\-\/]/); |
| 301 | |
David Benjamin | c895d6b | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 302 | my $mnemonic = $self->{opcode}->mnemonic(); |
| 303 | ($self->{asterisk}) && ($sz="q") || |
| 304 | ($mnemonic =~ /^v?mov([qd])$/) && ($sz=$1) || |
| 305 | ($mnemonic =~ /^v?pinsr([qdwb])$/) && ($sz=$1) || |
| 306 | ($mnemonic =~ /^vpbroadcast([qdwb])$/) && ($sz=$1) || |
| 307 | ($mnemonic =~ /^v(?!perm)[a-z]+[fi]128$/) && ($sz="x"); |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 308 | |
Robert Sloan | 5d62578 | 2017-02-13 09:55:39 -0800 | [diff] [blame] | 309 | $self->{opmask} =~ s/%(k[0-7])/$1/; |
| 310 | |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 311 | if (defined($self->{index})) { |
Robert Sloan | 5d62578 | 2017-02-13 09:55:39 -0800 | [diff] [blame] | 312 | sprintf "%s[%s%s*%d%s]%s",$szmap{$sz}, |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 313 | $self->{label}?"$self->{label}+":"", |
| 314 | $self->{index},$self->{scale}, |
Robert Sloan | 5d62578 | 2017-02-13 09:55:39 -0800 | [diff] [blame] | 315 | $self->{base}?"+$self->{base}":"", |
| 316 | $self->{opmask}; |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 317 | } elsif ($self->{base} eq "rip") { |
| 318 | sprintf "%s[%s]",$szmap{$sz},$self->{label}; |
| 319 | } else { |
Robert Sloan | 5d62578 | 2017-02-13 09:55:39 -0800 | [diff] [blame] | 320 | sprintf "%s[%s%s]%s", $szmap{$sz}, |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 321 | $self->{label}?"$self->{label}+":"", |
Robert Sloan | 5d62578 | 2017-02-13 09:55:39 -0800 | [diff] [blame] | 322 | $self->{base},$self->{opmask}; |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 323 | } |
| 324 | } |
| 325 | } |
| 326 | } |
| 327 | { package register; # pick up registers, which start with %. |
| 328 | sub re { |
David Benjamin | c895d6b | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 329 | my ($class, $line, $opcode) = @_; |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 330 | my $self = {}; |
David Benjamin | c895d6b | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 331 | my $ret; |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 332 | |
David Benjamin | c895d6b | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 333 | # optional * ----vvv--- appears in indirect jmp/call |
Robert Sloan | 5d62578 | 2017-02-13 09:55:39 -0800 | [diff] [blame] | 334 | if ($$line =~ /^(\*?)%(\w+)((?:{[^}]+})*)/) { |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 335 | bless $self,$class; |
| 336 | $self->{asterisk} = $1; |
| 337 | $self->{value} = $2; |
Robert Sloan | 5d62578 | 2017-02-13 09:55:39 -0800 | [diff] [blame] | 338 | $self->{opmask} = $3; |
David Benjamin | c895d6b | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 339 | $opcode->size($self->size()); |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 340 | $ret = $self; |
David Benjamin | c895d6b | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 341 | $$line = substr($$line,@+[0]); $$line =~ s/^\s+//; |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 342 | } |
| 343 | $ret; |
| 344 | } |
| 345 | sub size { |
| 346 | my $self = shift; |
David Benjamin | c895d6b | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 347 | my $ret; |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 348 | |
| 349 | if ($self->{value} =~ /^r[\d]+b$/i) { $ret="b"; } |
| 350 | elsif ($self->{value} =~ /^r[\d]+w$/i) { $ret="w"; } |
| 351 | elsif ($self->{value} =~ /^r[\d]+d$/i) { $ret="l"; } |
| 352 | elsif ($self->{value} =~ /^r[\w]+$/i) { $ret="q"; } |
| 353 | elsif ($self->{value} =~ /^[a-d][hl]$/i){ $ret="b"; } |
| 354 | elsif ($self->{value} =~ /^[\w]{2}l$/i) { $ret="b"; } |
| 355 | elsif ($self->{value} =~ /^[\w]{2}$/i) { $ret="w"; } |
| 356 | elsif ($self->{value} =~ /^e[a-z]{2}$/i){ $ret="l"; } |
| 357 | |
| 358 | $ret; |
| 359 | } |
| 360 | sub out { |
| 361 | my $self = shift; |
Robert Sloan | 5d62578 | 2017-02-13 09:55:39 -0800 | [diff] [blame] | 362 | if ($gas) { sprintf "%s%%%s%s", $self->{asterisk}, |
| 363 | $self->{value}, |
| 364 | $self->{opmask}; } |
| 365 | else { $self->{opmask} =~ s/%(k[0-7])/$1/; |
| 366 | $self->{value}.$self->{opmask}; } |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 367 | } |
| 368 | } |
| 369 | { package label; # pick up labels, which end with : |
| 370 | sub re { |
David Benjamin | c895d6b | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 371 | my ($class, $line) = @_; |
| 372 | my $self = {}; |
| 373 | my $ret; |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 374 | |
David Benjamin | c895d6b | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 375 | if ($$line =~ /(^[\.\w]+)\:/) { |
| 376 | bless $self,$class; |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 377 | $self->{value} = $1; |
| 378 | $ret = $self; |
David Benjamin | c895d6b | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 379 | $$line = substr($$line,@+[0]); $$line =~ s/^\s+//; |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 380 | |
| 381 | $self->{value} =~ s/^\.L/$decor/; |
| 382 | } |
| 383 | $ret; |
| 384 | } |
| 385 | sub out { |
| 386 | my $self = shift; |
| 387 | |
| 388 | if ($gas) { |
| 389 | my $func = ($globals{$self->{value}} or $self->{value}) . ":"; |
Robert Sloan | 5d62578 | 2017-02-13 09:55:39 -0800 | [diff] [blame] | 390 | if ($win64 && $current_function->{name} eq $self->{value} |
| 391 | && $current_function->{abi} eq "svr4") { |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 392 | $func .= "\n"; |
| 393 | $func .= " movq %rdi,8(%rsp)\n"; |
| 394 | $func .= " movq %rsi,16(%rsp)\n"; |
| 395 | $func .= " movq %rsp,%rax\n"; |
| 396 | $func .= "${decor}SEH_begin_$current_function->{name}:\n"; |
| 397 | my $narg = $current_function->{narg}; |
| 398 | $narg=6 if (!defined($narg)); |
| 399 | $func .= " movq %rcx,%rdi\n" if ($narg>0); |
| 400 | $func .= " movq %rdx,%rsi\n" if ($narg>1); |
| 401 | $func .= " movq %r8,%rdx\n" if ($narg>2); |
| 402 | $func .= " movq %r9,%rcx\n" if ($narg>3); |
| 403 | $func .= " movq 40(%rsp),%r8\n" if ($narg>4); |
| 404 | $func .= " movq 48(%rsp),%r9\n" if ($narg>5); |
| 405 | } |
| 406 | $func; |
| 407 | } elsif ($self->{value} ne "$current_function->{name}") { |
David Benjamin | c895d6b | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 408 | # Make all labels in masm global. |
| 409 | $self->{value} .= ":" if ($masm); |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 410 | $self->{value} . ":"; |
| 411 | } elsif ($win64 && $current_function->{abi} eq "svr4") { |
| 412 | my $func = "$current_function->{name}" . |
| 413 | ($nasm ? ":" : "\tPROC $current_function->{scope}") . |
| 414 | "\n"; |
David Benjamin | c895d6b | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 415 | $func .= " mov QWORD$PTR\[8+rsp\],rdi\t;WIN64 prologue\n"; |
| 416 | $func .= " mov QWORD$PTR\[16+rsp\],rsi\n"; |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 417 | $func .= " mov rax,rsp\n"; |
| 418 | $func .= "${decor}SEH_begin_$current_function->{name}:"; |
| 419 | $func .= ":" if ($masm); |
| 420 | $func .= "\n"; |
| 421 | my $narg = $current_function->{narg}; |
| 422 | $narg=6 if (!defined($narg)); |
| 423 | $func .= " mov rdi,rcx\n" if ($narg>0); |
| 424 | $func .= " mov rsi,rdx\n" if ($narg>1); |
| 425 | $func .= " mov rdx,r8\n" if ($narg>2); |
| 426 | $func .= " mov rcx,r9\n" if ($narg>3); |
David Benjamin | c895d6b | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 427 | $func .= " mov r8,QWORD$PTR\[40+rsp\]\n" if ($narg>4); |
| 428 | $func .= " mov r9,QWORD$PTR\[48+rsp\]\n" if ($narg>5); |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 429 | $func .= "\n"; |
| 430 | } else { |
| 431 | "$current_function->{name}". |
| 432 | ($nasm ? ":" : "\tPROC $current_function->{scope}"); |
| 433 | } |
| 434 | } |
| 435 | } |
Robert Sloan | a94fe05 | 2017-02-21 08:49:28 -0800 | [diff] [blame] | 436 | { package expr; # pick up expressions |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 437 | sub re { |
David Benjamin | c895d6b | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 438 | my ($class, $line, $opcode) = @_; |
| 439 | my $self = {}; |
| 440 | my $ret; |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 441 | |
David Benjamin | c895d6b | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 442 | if ($$line =~ /(^[^,]+)/) { |
| 443 | bless $self,$class; |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 444 | $self->{value} = $1; |
| 445 | $ret = $self; |
David Benjamin | c895d6b | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 446 | $$line = substr($$line,@+[0]); $$line =~ s/^\s+//; |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 447 | |
| 448 | $self->{value} =~ s/\@PLT// if (!$elf); |
| 449 | $self->{value} =~ s/([_a-z][_a-z0-9]*)/$globals{$1} or $1/gei; |
| 450 | $self->{value} =~ s/\.L/$decor/g; |
David Benjamin | c895d6b | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 451 | $self->{opcode} = $opcode; |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 452 | } |
| 453 | $ret; |
| 454 | } |
| 455 | sub out { |
| 456 | my $self = shift; |
David Benjamin | c895d6b | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 457 | if ($nasm && $self->{opcode}->mnemonic()=~m/^j(?![re]cxz)/) { |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 458 | "NEAR ".$self->{value}; |
| 459 | } else { |
| 460 | $self->{value}; |
| 461 | } |
| 462 | } |
| 463 | } |
Robert Sloan | a94fe05 | 2017-02-21 08:49:28 -0800 | [diff] [blame] | 464 | { package cfi_directive; |
| 465 | # CFI directives annotate instructions that are significant for |
| 466 | # stack unwinding procedure compliant with DWARF specification, |
| 467 | # see http://dwarfstd.org/. Besides naturally expected for this |
| 468 | # script platform-specific filtering function, this module adds |
| 469 | # three auxiliary synthetic directives not recognized by [GNU] |
| 470 | # assembler: |
| 471 | # |
| 472 | # - .cfi_push to annotate push instructions in prologue, which |
| 473 | # translates to .cfi_adjust_cfa_offset (if needed) and |
| 474 | # .cfi_offset; |
| 475 | # - .cfi_pop to annotate pop instructions in epilogue, which |
| 476 | # translates to .cfi_adjust_cfa_offset (if needed) and |
| 477 | # .cfi_restore; |
| 478 | # - [and most notably] .cfi_cfa_expression which encodes |
| 479 | # DW_CFA_def_cfa_expression and passes it to .cfi_escape as |
| 480 | # byte vector; |
| 481 | # |
| 482 | # CFA expressions were introduced in DWARF specification version |
| 483 | # 3 and describe how to deduce CFA, Canonical Frame Address. This |
| 484 | # becomes handy if your stack frame is variable and you can't |
| 485 | # spare register for [previous] frame pointer. Suggested directive |
| 486 | # syntax is made-up mix of DWARF operator suffixes [subset of] |
| 487 | # and references to registers with optional bias. Following example |
| 488 | # describes offloaded *original* stack pointer at specific offset |
| 489 | # from *current* stack pointer: |
| 490 | # |
| 491 | # .cfi_cfa_expression %rsp+40,deref,+8 |
| 492 | # |
| 493 | # Final +8 has everything to do with the fact that CFA is defined |
| 494 | # as reference to top of caller's stack, and on x86_64 call to |
| 495 | # subroutine pushes 8-byte return address. In other words original |
| 496 | # stack pointer upon entry to a subroutine is 8 bytes off from CFA. |
| 497 | |
| 498 | # Below constants are taken from "DWARF Expressions" section of the |
| 499 | # DWARF specification, section is numbered 7.7 in versions 3 and 4. |
| 500 | my %DW_OP_simple = ( # no-arg operators, mapped directly |
| 501 | deref => 0x06, dup => 0x12, |
| 502 | drop => 0x13, over => 0x14, |
| 503 | pick => 0x15, swap => 0x16, |
| 504 | rot => 0x17, xderef => 0x18, |
| 505 | |
| 506 | abs => 0x19, and => 0x1a, |
| 507 | div => 0x1b, minus => 0x1c, |
| 508 | mod => 0x1d, mul => 0x1e, |
| 509 | neg => 0x1f, not => 0x20, |
| 510 | or => 0x21, plus => 0x22, |
| 511 | shl => 0x24, shr => 0x25, |
| 512 | shra => 0x26, xor => 0x27, |
| 513 | ); |
| 514 | |
| 515 | my %DW_OP_complex = ( # used in specific subroutines |
| 516 | constu => 0x10, # uleb128 |
| 517 | consts => 0x11, # sleb128 |
| 518 | plus_uconst => 0x23, # uleb128 |
| 519 | lit0 => 0x30, # add 0-31 to opcode |
| 520 | reg0 => 0x50, # add 0-31 to opcode |
| 521 | breg0 => 0x70, # add 0-31 to opcole, sleb128 |
| 522 | regx => 0x90, # uleb28 |
| 523 | fbreg => 0x91, # sleb128 |
| 524 | bregx => 0x92, # uleb128, sleb128 |
| 525 | piece => 0x93, # uleb128 |
| 526 | ); |
| 527 | |
| 528 | # Following constants are defined in x86_64 ABI supplement, for |
Robert Sloan | ab8b888 | 2018-03-26 11:39:51 -0700 | [diff] [blame^] | 529 | # example available at https://www.uclibc.org/docs/psABI-x86_64.pdf, |
Robert Sloan | a94fe05 | 2017-02-21 08:49:28 -0800 | [diff] [blame] | 530 | # see section 3.7 "Stack Unwind Algorithm". |
| 531 | my %DW_reg_idx = ( |
| 532 | "%rax"=>0, "%rdx"=>1, "%rcx"=>2, "%rbx"=>3, |
| 533 | "%rsi"=>4, "%rdi"=>5, "%rbp"=>6, "%rsp"=>7, |
| 534 | "%r8" =>8, "%r9" =>9, "%r10"=>10, "%r11"=>11, |
| 535 | "%r12"=>12, "%r13"=>13, "%r14"=>14, "%r15"=>15 |
| 536 | ); |
| 537 | |
| 538 | my ($cfa_reg, $cfa_rsp); |
| 539 | |
| 540 | # [us]leb128 format is variable-length integer representation base |
| 541 | # 2^128, with most significant bit of each byte being 0 denoting |
Robert Sloan | ab8b888 | 2018-03-26 11:39:51 -0700 | [diff] [blame^] | 542 | # *last* most significant digit. See "Variable Length Data" in the |
Robert Sloan | a94fe05 | 2017-02-21 08:49:28 -0800 | [diff] [blame] | 543 | # DWARF specification, numbered 7.6 at least in versions 3 and 4. |
| 544 | sub sleb128 { |
| 545 | use integer; # get right shift extend sign |
| 546 | |
| 547 | my $val = shift; |
| 548 | my $sign = ($val < 0) ? -1 : 0; |
| 549 | my @ret = (); |
| 550 | |
| 551 | while(1) { |
| 552 | push @ret, $val&0x7f; |
| 553 | |
| 554 | # see if remaining bits are same and equal to most |
| 555 | # significant bit of the current digit, if so, it's |
| 556 | # last digit... |
| 557 | last if (($val>>6) == $sign); |
| 558 | |
| 559 | @ret[-1] |= 0x80; |
| 560 | $val >>= 7; |
| 561 | } |
| 562 | |
| 563 | return @ret; |
| 564 | } |
| 565 | sub uleb128 { |
| 566 | my $val = shift; |
| 567 | my @ret = (); |
| 568 | |
| 569 | while(1) { |
| 570 | push @ret, $val&0x7f; |
| 571 | |
| 572 | # see if it's last significant digit... |
| 573 | last if (($val >>= 7) == 0); |
| 574 | |
| 575 | @ret[-1] |= 0x80; |
| 576 | } |
| 577 | |
| 578 | return @ret; |
| 579 | } |
| 580 | sub const { |
| 581 | my $val = shift; |
| 582 | |
| 583 | if ($val >= 0 && $val < 32) { |
| 584 | return ($DW_OP_complex{lit0}+$val); |
| 585 | } |
| 586 | return ($DW_OP_complex{consts}, sleb128($val)); |
| 587 | } |
| 588 | sub reg { |
| 589 | my $val = shift; |
| 590 | |
| 591 | return if ($val !~ m/^(%r\w+)(?:([\+\-])((?:0x)?[0-9a-f]+))?/); |
| 592 | |
| 593 | my $reg = $DW_reg_idx{$1}; |
| 594 | my $off = eval ("0 $2 $3"); |
| 595 | |
| 596 | return (($DW_OP_complex{breg0} + $reg), sleb128($off)); |
| 597 | # Yes, we use DW_OP_bregX+0 to push register value and not |
| 598 | # DW_OP_regX, because latter would require even DW_OP_piece, |
| 599 | # which would be a waste under the circumstances. If you have |
| 600 | # to use DWP_OP_reg, use "regx:N"... |
| 601 | } |
| 602 | sub cfa_expression { |
| 603 | my $line = shift; |
| 604 | my @ret; |
| 605 | |
| 606 | foreach my $token (split(/,\s*/,$line)) { |
| 607 | if ($token =~ /^%r/) { |
| 608 | push @ret,reg($token); |
| 609 | } elsif ($token =~ /((?:0x)?[0-9a-f]+)\((%r\w+)\)/) { |
| 610 | push @ret,reg("$2+$1"); |
| 611 | } elsif ($token =~ /(\w+):(\-?(?:0x)?[0-9a-f]+)(U?)/i) { |
| 612 | my $i = 1*eval($2); |
| 613 | push @ret,$DW_OP_complex{$1}, ($3 ? uleb128($i) : sleb128($i)); |
| 614 | } elsif (my $i = 1*eval($token) or $token eq "0") { |
| 615 | if ($token =~ /^\+/) { |
| 616 | push @ret,$DW_OP_complex{plus_uconst},uleb128($i); |
| 617 | } else { |
| 618 | push @ret,const($i); |
| 619 | } |
| 620 | } else { |
| 621 | push @ret,$DW_OP_simple{$token}; |
| 622 | } |
| 623 | } |
| 624 | |
| 625 | # Finally we return DW_CFA_def_cfa_expression, 15, followed by |
| 626 | # length of the expression and of course the expression itself. |
| 627 | return (15,scalar(@ret),@ret); |
| 628 | } |
| 629 | sub re { |
| 630 | my ($class, $line) = @_; |
| 631 | my $self = {}; |
| 632 | my $ret; |
| 633 | |
| 634 | if ($$line =~ s/^\s*\.cfi_(\w+)\s*//) { |
| 635 | bless $self,$class; |
| 636 | $ret = $self; |
| 637 | undef $self->{value}; |
| 638 | my $dir = $1; |
| 639 | |
| 640 | SWITCH: for ($dir) { |
| 641 | # What is $cfa_rsp? Effectively it's difference between %rsp |
| 642 | # value and current CFA, Canonical Frame Address, which is |
| 643 | # why it starts with -8. Recall that CFA is top of caller's |
| 644 | # stack... |
| 645 | /startproc/ && do { ($cfa_reg, $cfa_rsp) = ("%rsp", -8); last; }; |
| 646 | /endproc/ && do { ($cfa_reg, $cfa_rsp) = ("%rsp", 0); last; }; |
| 647 | /def_cfa_register/ |
| 648 | && do { $cfa_reg = $$line; last; }; |
| 649 | /def_cfa_offset/ |
| 650 | && do { $cfa_rsp = -1*eval($$line) if ($cfa_reg eq "%rsp"); |
| 651 | last; |
| 652 | }; |
| 653 | /adjust_cfa_offset/ |
| 654 | && do { $cfa_rsp -= 1*eval($$line) if ($cfa_reg eq "%rsp"); |
| 655 | last; |
| 656 | }; |
| 657 | /def_cfa/ && do { if ($$line =~ /(%r\w+)\s*,\s*(.+)/) { |
| 658 | $cfa_reg = $1; |
| 659 | $cfa_rsp = -1*eval($2) if ($cfa_reg eq "%rsp"); |
| 660 | } |
| 661 | last; |
| 662 | }; |
| 663 | /push/ && do { $dir = undef; |
| 664 | $cfa_rsp -= 8; |
| 665 | if ($cfa_reg eq "%rsp") { |
| 666 | $self->{value} = ".cfi_adjust_cfa_offset\t8\n"; |
| 667 | } |
| 668 | $self->{value} .= ".cfi_offset\t$$line,$cfa_rsp"; |
| 669 | last; |
| 670 | }; |
| 671 | /pop/ && do { $dir = undef; |
| 672 | $cfa_rsp += 8; |
| 673 | if ($cfa_reg eq "%rsp") { |
| 674 | $self->{value} = ".cfi_adjust_cfa_offset\t-8\n"; |
| 675 | } |
| 676 | $self->{value} .= ".cfi_restore\t$$line"; |
| 677 | last; |
| 678 | }; |
| 679 | /cfa_expression/ |
| 680 | && do { $dir = undef; |
| 681 | $self->{value} = ".cfi_escape\t" . |
| 682 | join(",", map(sprintf("0x%02x", $_), |
| 683 | cfa_expression($$line))); |
| 684 | last; |
| 685 | }; |
| 686 | } |
| 687 | |
| 688 | $self->{value} = ".cfi_$dir\t$$line" if ($dir); |
| 689 | |
| 690 | $$line = ""; |
| 691 | } |
| 692 | |
| 693 | return $ret; |
| 694 | } |
| 695 | sub out { |
| 696 | my $self = shift; |
| 697 | return ($elf ? $self->{value} : undef); |
| 698 | } |
| 699 | } |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 700 | { package directive; # pick up directives, which start with . |
| 701 | sub re { |
David Benjamin | c895d6b | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 702 | my ($class, $line) = @_; |
| 703 | my $self = {}; |
| 704 | my $ret; |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 705 | my $dir; |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 706 | |
Robert Sloan | a94fe05 | 2017-02-21 08:49:28 -0800 | [diff] [blame] | 707 | # chain-call to cfi_directive |
| 708 | $ret = cfi_directive->re($line) and return $ret; |
| 709 | |
David Benjamin | c895d6b | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 710 | if ($$line =~ /^\s*(\.\w+)/) { |
| 711 | bless $self,$class; |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 712 | $dir = $1; |
| 713 | $ret = $self; |
| 714 | undef $self->{value}; |
David Benjamin | c895d6b | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 715 | $$line = substr($$line,@+[0]); $$line =~ s/^\s+//; |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 716 | |
| 717 | SWITCH: for ($dir) { |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 718 | /\.global|\.globl|\.extern/ |
David Benjamin | c895d6b | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 719 | && do { $globals{$$line} = $prefix . $$line; |
| 720 | $$line = $globals{$$line} if ($prefix); |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 721 | last; |
| 722 | }; |
David Benjamin | c895d6b | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 723 | /\.type/ && do { my ($sym,$type,$narg) = split(',',$$line); |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 724 | if ($type eq "\@function") { |
| 725 | undef $current_function; |
| 726 | $current_function->{name} = $sym; |
| 727 | $current_function->{abi} = "svr4"; |
| 728 | $current_function->{narg} = $narg; |
| 729 | $current_function->{scope} = defined($globals{$sym})?"PUBLIC":"PRIVATE"; |
| 730 | } elsif ($type eq "\@abi-omnipotent") { |
| 731 | undef $current_function; |
| 732 | $current_function->{name} = $sym; |
| 733 | $current_function->{scope} = defined($globals{$sym})?"PUBLIC":"PRIVATE"; |
| 734 | } |
David Benjamin | c895d6b | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 735 | $$line =~ s/\@abi\-omnipotent/\@function/; |
| 736 | $$line =~ s/\@function.*/\@function/; |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 737 | last; |
| 738 | }; |
David Benjamin | c895d6b | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 739 | /\.asciz/ && do { if ($$line =~ /^"(.*)"$/) { |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 740 | $dir = ".byte"; |
David Benjamin | c895d6b | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 741 | $$line = join(",",unpack("C*",$1),0); |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 742 | } |
| 743 | last; |
| 744 | }; |
| 745 | /\.rva|\.long|\.quad/ |
David Benjamin | c895d6b | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 746 | && do { $$line =~ s/([_a-z][_a-z0-9]*)/$globals{$1} or $1/gei; |
| 747 | $$line =~ s/\.L/$decor/g; |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 748 | last; |
| 749 | }; |
| 750 | } |
| 751 | |
| 752 | if ($gas) { |
David Benjamin | c895d6b | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 753 | $self->{value} = $dir . "\t" . $$line; |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 754 | |
| 755 | if ($dir =~ /\.extern/) { |
Adam Langley | a4fb56a | 2015-03-06 11:08:23 -0800 | [diff] [blame] | 756 | if ($flavour eq "elf") { |
David Benjamin | c895d6b | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 757 | $self->{value} .= "\n.hidden $$line"; |
Adam Langley | a4fb56a | 2015-03-06 11:08:23 -0800 | [diff] [blame] | 758 | } else { |
| 759 | $self->{value} = ""; |
| 760 | } |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 761 | } elsif (!$elf && $dir =~ /\.type/) { |
| 762 | $self->{value} = ""; |
| 763 | $self->{value} = ".def\t" . ($globals{$1} or $1) . ";\t" . |
| 764 | (defined($globals{$1})?".scl 2;":".scl 3;") . |
| 765 | "\t.type 32;\t.endef" |
David Benjamin | c895d6b | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 766 | if ($win64 && $$line =~ /([^,]+),\@function/); |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 767 | } elsif (!$elf && $dir =~ /\.size/) { |
| 768 | $self->{value} = ""; |
| 769 | if (defined($current_function)) { |
| 770 | $self->{value} .= "${decor}SEH_end_$current_function->{name}:" |
| 771 | if ($win64 && $current_function->{abi} eq "svr4"); |
| 772 | undef $current_function; |
| 773 | } |
| 774 | } elsif (!$elf && $dir =~ /\.align/) { |
David Benjamin | c895d6b | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 775 | $self->{value} = ".p2align\t" . (log($$line)/log(2)); |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 776 | } elsif ($dir eq ".section") { |
David Benjamin | c895d6b | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 777 | $current_segment=$$line; |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 778 | if (!$elf && $current_segment eq ".init") { |
| 779 | if ($flavour eq "macosx") { $self->{value} = ".mod_init_func"; } |
| 780 | elsif ($flavour eq "mingw64") { $self->{value} = ".section\t.ctors"; } |
| 781 | } |
| 782 | } elsif ($dir =~ /\.(text|data)/) { |
| 783 | $current_segment=".$1"; |
| 784 | } elsif ($dir =~ /\.global|\.globl|\.extern/) { |
| 785 | if ($flavour eq "macosx") { |
David Benjamin | c895d6b | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 786 | $self->{value} .= "\n.private_extern $$line"; |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 787 | } else { |
David Benjamin | c895d6b | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 788 | $self->{value} .= "\n.hidden $$line"; |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 789 | } |
| 790 | } elsif ($dir =~ /\.hidden/) { |
David Benjamin | c895d6b | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 791 | if ($flavour eq "macosx") { $self->{value} = ".private_extern\t$prefix$$line"; } |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 792 | elsif ($flavour eq "mingw64") { $self->{value} = ""; } |
| 793 | } elsif ($dir =~ /\.comm/) { |
David Benjamin | c895d6b | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 794 | $self->{value} = "$dir\t$prefix$$line"; |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 795 | $self->{value} =~ s|,([0-9]+),([0-9]+)$|",$1,".log($2)/log(2)|e if ($flavour eq "macosx"); |
| 796 | } |
David Benjamin | c895d6b | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 797 | $$line = ""; |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 798 | return $self; |
| 799 | } |
| 800 | |
| 801 | # non-gas case or nasm/masm |
| 802 | SWITCH: for ($dir) { |
| 803 | /\.text/ && do { my $v=undef; |
| 804 | if ($nasm) { |
| 805 | $v="section .text code align=64\n"; |
| 806 | } else { |
| 807 | $v="$current_segment\tENDS\n" if ($current_segment); |
| 808 | $current_segment = ".text\$"; |
| 809 | $v.="$current_segment\tSEGMENT "; |
| 810 | $v.=$masm>=$masmref ? "ALIGN(256)" : "PAGE"; |
| 811 | $v.=" 'CODE'"; |
| 812 | } |
| 813 | $self->{value} = $v; |
| 814 | last; |
| 815 | }; |
| 816 | /\.data/ && do { my $v=undef; |
| 817 | if ($nasm) { |
| 818 | $v="section .data data align=8\n"; |
| 819 | } else { |
| 820 | $v="$current_segment\tENDS\n" if ($current_segment); |
| 821 | $current_segment = "_DATA"; |
| 822 | $v.="$current_segment\tSEGMENT"; |
| 823 | } |
| 824 | $self->{value} = $v; |
| 825 | last; |
| 826 | }; |
| 827 | /\.section/ && do { my $v=undef; |
David Benjamin | c895d6b | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 828 | $$line =~ s/([^,]*).*/$1/; |
| 829 | $$line = ".CRT\$XCU" if ($$line eq ".init"); |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 830 | if ($nasm) { |
David Benjamin | c895d6b | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 831 | $v="section $$line"; |
| 832 | if ($$line=~/\.([px])data/) { |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 833 | $v.=" rdata align="; |
| 834 | $v.=$1 eq "p"? 4 : 8; |
David Benjamin | c895d6b | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 835 | } elsif ($$line=~/\.CRT\$/i) { |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 836 | $v.=" rdata align=8"; |
| 837 | } |
| 838 | } else { |
| 839 | $v="$current_segment\tENDS\n" if ($current_segment); |
David Benjamin | c895d6b | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 840 | $v.="$$line\tSEGMENT"; |
| 841 | if ($$line=~/\.([px])data/) { |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 842 | $v.=" READONLY"; |
| 843 | $v.=" ALIGN(".($1 eq "p" ? 4 : 8).")" if ($masm>=$masmref); |
David Benjamin | c895d6b | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 844 | } elsif ($$line=~/\.CRT\$/i) { |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 845 | $v.=" READONLY "; |
| 846 | $v.=$masm>=$masmref ? "ALIGN(8)" : "DWORD"; |
| 847 | } |
| 848 | } |
David Benjamin | c895d6b | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 849 | $current_segment = $$line; |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 850 | $self->{value} = $v; |
| 851 | last; |
| 852 | }; |
David Benjamin | c895d6b | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 853 | /\.extern/ && do { $self->{value} = "EXTERN\t".$$line; |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 854 | $self->{value} .= ":NEAR" if ($masm); |
| 855 | last; |
| 856 | }; |
| 857 | /\.globl|.global/ |
| 858 | && do { $self->{value} = $masm?"PUBLIC":"global"; |
David Benjamin | c895d6b | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 859 | $self->{value} .= "\t".$$line; |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 860 | last; |
| 861 | }; |
| 862 | /\.size/ && do { if (defined($current_function)) { |
| 863 | undef $self->{value}; |
| 864 | if ($current_function->{abi} eq "svr4") { |
| 865 | $self->{value}="${decor}SEH_end_$current_function->{name}:"; |
| 866 | $self->{value}.=":\n" if($masm); |
| 867 | } |
| 868 | $self->{value}.="$current_function->{name}\tENDP" if($masm && $current_function->{name}); |
| 869 | undef $current_function; |
| 870 | } |
| 871 | last; |
| 872 | }; |
David Benjamin | c895d6b | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 873 | /\.align/ && do { my $max = ($masm && $masm>=$masmref) ? 256 : 4096; |
| 874 | $self->{value} = "ALIGN\t".($$line>$max?$max:$$line); |
| 875 | last; |
| 876 | }; |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 877 | /\.(value|long|rva|quad)/ |
| 878 | && do { my $sz = substr($1,0,1); |
David Benjamin | c895d6b | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 879 | my @arr = split(/,\s*/,$$line); |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 880 | my $last = pop(@arr); |
| 881 | my $conv = sub { my $var=shift; |
| 882 | $var=~s/^(0b[0-1]+)/oct($1)/eig; |
| 883 | $var=~s/^0x([0-9a-f]+)/0$1h/ig if ($masm); |
| 884 | if ($sz eq "D" && ($current_segment=~/.[px]data/ || $dir eq ".rva")) |
| 885 | { $var=~s/([_a-z\$\@][_a-z0-9\$\@]*)/$nasm?"$1 wrt ..imagebase":"imagerel $1"/egi; } |
| 886 | $var; |
Robert Sloan | a94fe05 | 2017-02-21 08:49:28 -0800 | [diff] [blame] | 887 | }; |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 888 | |
| 889 | $sz =~ tr/bvlrq/BWDDQ/; |
| 890 | $self->{value} = "\tD$sz\t"; |
| 891 | for (@arr) { $self->{value} .= &$conv($_).","; } |
| 892 | $self->{value} .= &$conv($last); |
| 893 | last; |
| 894 | }; |
David Benjamin | c895d6b | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 895 | /\.byte/ && do { my @str=split(/,\s*/,$$line); |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 896 | map(s/(0b[0-1]+)/oct($1)/eig,@str); |
Robert Sloan | a94fe05 | 2017-02-21 08:49:28 -0800 | [diff] [blame] | 897 | map(s/0x([0-9a-f]+)/0$1h/ig,@str) if ($masm); |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 898 | while ($#str>15) { |
| 899 | $self->{value}.="DB\t" |
| 900 | .join(",",@str[0..15])."\n"; |
| 901 | foreach (0..15) { shift @str; } |
| 902 | } |
| 903 | $self->{value}.="DB\t" |
| 904 | .join(",",@str) if (@str); |
| 905 | last; |
| 906 | }; |
David Benjamin | c895d6b | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 907 | /\.comm/ && do { my @str=split(/,\s*/,$$line); |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 908 | my $v=undef; |
| 909 | if ($nasm) { |
| 910 | $v.="common $prefix@str[0] @str[1]"; |
| 911 | } else { |
| 912 | $v="$current_segment\tENDS\n" if ($current_segment); |
| 913 | $current_segment = "_DATA"; |
| 914 | $v.="$current_segment\tSEGMENT\n"; |
| 915 | $v.="COMM @str[0]:DWORD:".@str[1]/4; |
| 916 | } |
| 917 | $self->{value} = $v; |
| 918 | last; |
| 919 | }; |
| 920 | } |
David Benjamin | c895d6b | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 921 | $$line = ""; |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 922 | } |
| 923 | |
| 924 | $ret; |
| 925 | } |
| 926 | sub out { |
| 927 | my $self = shift; |
| 928 | $self->{value}; |
| 929 | } |
| 930 | } |
| 931 | |
David Benjamin | c895d6b | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 932 | # Upon initial x86_64 introduction SSE>2 extensions were not introduced |
| 933 | # yet. In order not to be bothered by tracing exact assembler versions, |
| 934 | # but at the same time to provide a bare security minimum of AES-NI, we |
| 935 | # hard-code some instructions. Extensions past AES-NI on the other hand |
| 936 | # are traced by examining assembler version in individual perlasm |
| 937 | # modules... |
| 938 | |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 939 | my %regrm = ( "%eax"=>0, "%ecx"=>1, "%edx"=>2, "%ebx"=>3, |
| 940 | "%esp"=>4, "%ebp"=>5, "%esi"=>6, "%edi"=>7 ); |
| 941 | |
Robert Sloan | 5d62578 | 2017-02-13 09:55:39 -0800 | [diff] [blame] | 942 | sub rex { |
| 943 | my $opcode=shift; |
| 944 | my ($dst,$src,$rex)=@_; |
| 945 | |
| 946 | $rex|=0x04 if($dst>=8); |
| 947 | $rex|=0x01 if($src>=8); |
| 948 | push @$opcode,($rex|0x40) if ($rex); |
| 949 | } |
| 950 | |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 951 | my $movq = sub { # elderly gas can't handle inter-register movq |
| 952 | my $arg = shift; |
| 953 | my @opcode=(0x66); |
| 954 | if ($arg =~ /%xmm([0-9]+),\s*%r(\w+)/) { |
| 955 | my ($src,$dst)=($1,$2); |
| 956 | if ($dst !~ /[0-9]+/) { $dst = $regrm{"%e$dst"}; } |
| 957 | rex(\@opcode,$src,$dst,0x8); |
| 958 | push @opcode,0x0f,0x7e; |
| 959 | push @opcode,0xc0|(($src&7)<<3)|($dst&7); # ModR/M |
| 960 | @opcode; |
| 961 | } elsif ($arg =~ /%r(\w+),\s*%xmm([0-9]+)/) { |
| 962 | my ($src,$dst)=($2,$1); |
| 963 | if ($dst !~ /[0-9]+/) { $dst = $regrm{"%e$dst"}; } |
| 964 | rex(\@opcode,$src,$dst,0x8); |
| 965 | push @opcode,0x0f,0x6e; |
| 966 | push @opcode,0xc0|(($src&7)<<3)|($dst&7); # ModR/M |
| 967 | @opcode; |
| 968 | } else { |
| 969 | (); |
| 970 | } |
| 971 | }; |
| 972 | |
| 973 | my $pextrd = sub { |
| 974 | if (shift =~ /\$([0-9]+),\s*%xmm([0-9]+),\s*(%\w+)/) { |
| 975 | my @opcode=(0x66); |
David Benjamin | c895d6b | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 976 | my $imm=$1; |
| 977 | my $src=$2; |
| 978 | my $dst=$3; |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 979 | if ($dst =~ /%r([0-9]+)d/) { $dst = $1; } |
| 980 | elsif ($dst =~ /%e/) { $dst = $regrm{$dst}; } |
| 981 | rex(\@opcode,$src,$dst); |
| 982 | push @opcode,0x0f,0x3a,0x16; |
| 983 | push @opcode,0xc0|(($src&7)<<3)|($dst&7); # ModR/M |
| 984 | push @opcode,$imm; |
| 985 | @opcode; |
| 986 | } else { |
| 987 | (); |
| 988 | } |
| 989 | }; |
| 990 | |
| 991 | my $pinsrd = sub { |
| 992 | if (shift =~ /\$([0-9]+),\s*(%\w+),\s*%xmm([0-9]+)/) { |
| 993 | my @opcode=(0x66); |
David Benjamin | c895d6b | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 994 | my $imm=$1; |
| 995 | my $src=$2; |
| 996 | my $dst=$3; |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 997 | if ($src =~ /%r([0-9]+)/) { $src = $1; } |
| 998 | elsif ($src =~ /%e/) { $src = $regrm{$src}; } |
| 999 | rex(\@opcode,$dst,$src); |
| 1000 | push @opcode,0x0f,0x3a,0x22; |
| 1001 | push @opcode,0xc0|(($dst&7)<<3)|($src&7); # ModR/M |
| 1002 | push @opcode,$imm; |
| 1003 | @opcode; |
| 1004 | } else { |
| 1005 | (); |
| 1006 | } |
| 1007 | }; |
| 1008 | |
| 1009 | my $pshufb = sub { |
| 1010 | if (shift =~ /%xmm([0-9]+),\s*%xmm([0-9]+)/) { |
| 1011 | my @opcode=(0x66); |
| 1012 | rex(\@opcode,$2,$1); |
| 1013 | push @opcode,0x0f,0x38,0x00; |
| 1014 | push @opcode,0xc0|($1&7)|(($2&7)<<3); # ModR/M |
| 1015 | @opcode; |
| 1016 | } else { |
| 1017 | (); |
| 1018 | } |
| 1019 | }; |
| 1020 | |
| 1021 | my $palignr = sub { |
| 1022 | if (shift =~ /\$([0-9]+),\s*%xmm([0-9]+),\s*%xmm([0-9]+)/) { |
| 1023 | my @opcode=(0x66); |
| 1024 | rex(\@opcode,$3,$2); |
| 1025 | push @opcode,0x0f,0x3a,0x0f; |
| 1026 | push @opcode,0xc0|($2&7)|(($3&7)<<3); # ModR/M |
| 1027 | push @opcode,$1; |
| 1028 | @opcode; |
| 1029 | } else { |
| 1030 | (); |
| 1031 | } |
| 1032 | }; |
| 1033 | |
| 1034 | my $pclmulqdq = sub { |
| 1035 | if (shift =~ /\$([x0-9a-f]+),\s*%xmm([0-9]+),\s*%xmm([0-9]+)/) { |
| 1036 | my @opcode=(0x66); |
| 1037 | rex(\@opcode,$3,$2); |
| 1038 | push @opcode,0x0f,0x3a,0x44; |
| 1039 | push @opcode,0xc0|($2&7)|(($3&7)<<3); # ModR/M |
| 1040 | my $c=$1; |
| 1041 | push @opcode,$c=~/^0/?oct($c):$c; |
| 1042 | @opcode; |
| 1043 | } else { |
| 1044 | (); |
| 1045 | } |
| 1046 | }; |
| 1047 | |
| 1048 | my $rdrand = sub { |
| 1049 | if (shift =~ /%[er](\w+)/) { |
| 1050 | my @opcode=(); |
| 1051 | my $dst=$1; |
| 1052 | if ($dst !~ /[0-9]+/) { $dst = $regrm{"%e$dst"}; } |
Robert Sloan | a94fe05 | 2017-02-21 08:49:28 -0800 | [diff] [blame] | 1053 | rex(\@opcode,0,$dst,8); |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 1054 | push @opcode,0x0f,0xc7,0xf0|($dst&7); |
| 1055 | @opcode; |
| 1056 | } else { |
| 1057 | (); |
| 1058 | } |
| 1059 | }; |
| 1060 | |
| 1061 | my $rdseed = sub { |
| 1062 | if (shift =~ /%[er](\w+)/) { |
| 1063 | my @opcode=(); |
| 1064 | my $dst=$1; |
| 1065 | if ($dst !~ /[0-9]+/) { $dst = $regrm{"%e$dst"}; } |
Robert Sloan | a94fe05 | 2017-02-21 08:49:28 -0800 | [diff] [blame] | 1066 | rex(\@opcode,0,$dst,8); |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 1067 | push @opcode,0x0f,0xc7,0xf8|($dst&7); |
| 1068 | @opcode; |
| 1069 | } else { |
| 1070 | (); |
| 1071 | } |
| 1072 | }; |
| 1073 | |
Robert Sloan | 5d62578 | 2017-02-13 09:55:39 -0800 | [diff] [blame] | 1074 | # Not all AVX-capable assemblers recognize AMD XOP extension. Since we |
| 1075 | # are using only two instructions hand-code them in order to be excused |
| 1076 | # from chasing assembler versions... |
| 1077 | |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 1078 | sub rxb { |
David Benjamin | c895d6b | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 1079 | my $opcode=shift; |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 1080 | my ($dst,$src1,$src2,$rxb)=@_; |
| 1081 | |
| 1082 | $rxb|=0x7<<5; |
| 1083 | $rxb&=~(0x04<<5) if($dst>=8); |
| 1084 | $rxb&=~(0x01<<5) if($src1>=8); |
| 1085 | $rxb&=~(0x02<<5) if($src2>=8); |
David Benjamin | c895d6b | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 1086 | push @$opcode,$rxb; |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 1087 | } |
| 1088 | |
| 1089 | my $vprotd = sub { |
| 1090 | if (shift =~ /\$([x0-9a-f]+),\s*%xmm([0-9]+),\s*%xmm([0-9]+)/) { |
| 1091 | my @opcode=(0x8f); |
| 1092 | rxb(\@opcode,$3,$2,-1,0x08); |
| 1093 | push @opcode,0x78,0xc2; |
| 1094 | push @opcode,0xc0|($2&7)|(($3&7)<<3); # ModR/M |
| 1095 | my $c=$1; |
| 1096 | push @opcode,$c=~/^0/?oct($c):$c; |
| 1097 | @opcode; |
| 1098 | } else { |
| 1099 | (); |
| 1100 | } |
| 1101 | }; |
| 1102 | |
| 1103 | my $vprotq = sub { |
| 1104 | if (shift =~ /\$([x0-9a-f]+),\s*%xmm([0-9]+),\s*%xmm([0-9]+)/) { |
| 1105 | my @opcode=(0x8f); |
| 1106 | rxb(\@opcode,$3,$2,-1,0x08); |
| 1107 | push @opcode,0x78,0xc3; |
| 1108 | push @opcode,0xc0|($2&7)|(($3&7)<<3); # ModR/M |
| 1109 | my $c=$1; |
| 1110 | push @opcode,$c=~/^0/?oct($c):$c; |
| 1111 | @opcode; |
| 1112 | } else { |
| 1113 | (); |
| 1114 | } |
| 1115 | }; |
| 1116 | |
Robert Sloan | 5d62578 | 2017-02-13 09:55:39 -0800 | [diff] [blame] | 1117 | # Intel Control-flow Enforcement Technology extension. All functions and |
| 1118 | # indirect branch targets will have to start with this instruction... |
| 1119 | |
David Benjamin | c895d6b | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 1120 | my $endbranch = sub { |
| 1121 | (0xf3,0x0f,0x1e,0xfa); |
| 1122 | }; |
| 1123 | |
Robert Sloan | 5d62578 | 2017-02-13 09:55:39 -0800 | [diff] [blame] | 1124 | ######################################################################## |
| 1125 | |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 1126 | if ($nasm) { |
| 1127 | print <<___; |
| 1128 | default rel |
| 1129 | %define XMMWORD |
| 1130 | %define YMMWORD |
| 1131 | %define ZMMWORD |
| 1132 | ___ |
| 1133 | } elsif ($masm) { |
| 1134 | print <<___; |
| 1135 | OPTION DOTNAME |
| 1136 | ___ |
| 1137 | } |
Robert Sloan | 6f79a50 | 2017-04-03 09:16:40 -0700 | [diff] [blame] | 1138 | print STDOUT "#if defined(__x86_64__) && !defined(OPENSSL_NO_ASM)\n" if ($gas); |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 1139 | |
David Benjamin | c895d6b | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 1140 | while(defined(my $line=<>)) { |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 1141 | |
David Benjamin | c895d6b | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 1142 | $line =~ s|\R$||; # Better chomp |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 1143 | |
| 1144 | $line =~ s|[#!].*$||; # get rid of asm-style comments... |
| 1145 | $line =~ s|/\*.*\*/||; # ... and C-style comments... |
| 1146 | $line =~ s|^\s+||; # ... and skip white spaces in beginning |
| 1147 | $line =~ s|\s+$||; # ... and at the end |
| 1148 | |
David Benjamin | c895d6b | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 1149 | if (my $label=label->re(\$line)) { print $label->out(); } |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 1150 | |
David Benjamin | c895d6b | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 1151 | if (my $directive=directive->re(\$line)) { |
| 1152 | printf "%s",$directive->out(); |
| 1153 | } elsif (my $opcode=opcode->re(\$line)) { |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 1154 | my $asm = eval("\$".$opcode->mnemonic()); |
Robert Sloan | a94fe05 | 2017-02-21 08:49:28 -0800 | [diff] [blame] | 1155 | |
David Benjamin | c895d6b | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 1156 | if ((ref($asm) eq 'CODE') && scalar(my @bytes=&$asm($line))) { |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 1157 | print $gas?".byte\t":"DB\t",join(',',@bytes),"\n"; |
| 1158 | next; |
| 1159 | } |
| 1160 | |
David Benjamin | c895d6b | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 1161 | my @args; |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 1162 | ARGUMENT: while (1) { |
David Benjamin | c895d6b | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 1163 | my $arg; |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 1164 | |
David Benjamin | c895d6b | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 1165 | ($arg=register->re(\$line, $opcode))|| |
| 1166 | ($arg=const->re(\$line)) || |
| 1167 | ($arg=ea->re(\$line, $opcode)) || |
| 1168 | ($arg=expr->re(\$line, $opcode)) || |
| 1169 | last ARGUMENT; |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 1170 | |
David Benjamin | c895d6b | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 1171 | push @args,$arg; |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 1172 | |
David Benjamin | c895d6b | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 1173 | last ARGUMENT if ($line !~ /^,/); |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 1174 | |
David Benjamin | c895d6b | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 1175 | $line =~ s/^,\s*//; |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 1176 | } # ARGUMENT: |
| 1177 | |
| 1178 | if ($#args>=0) { |
| 1179 | my $insn; |
David Benjamin | c895d6b | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 1180 | my $sz=$opcode->size(); |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 1181 | |
| 1182 | if ($gas) { |
| 1183 | $insn = $opcode->out($#args>=1?$args[$#args]->size():$sz); |
| 1184 | @args = map($_->out($sz),@args); |
| 1185 | printf "\t%s\t%s",$insn,join(",",@args); |
| 1186 | } else { |
| 1187 | $insn = $opcode->out(); |
| 1188 | foreach (@args) { |
| 1189 | my $arg = $_->out(); |
| 1190 | # $insn.=$sz compensates for movq, pinsrw, ... |
| 1191 | if ($arg =~ /^xmm[0-9]+$/) { $insn.=$sz; $sz="x" if(!$sz); last; } |
| 1192 | if ($arg =~ /^ymm[0-9]+$/) { $insn.=$sz; $sz="y" if(!$sz); last; } |
| 1193 | if ($arg =~ /^zmm[0-9]+$/) { $insn.=$sz; $sz="z" if(!$sz); last; } |
| 1194 | if ($arg =~ /^mm[0-9]+$/) { $insn.=$sz; $sz="q" if(!$sz); last; } |
| 1195 | } |
| 1196 | @args = reverse(@args); |
| 1197 | undef $sz if ($nasm && $opcode->mnemonic() eq "lea"); |
Robert Sloan | 8ff0355 | 2017-06-14 12:40:58 -0700 | [diff] [blame] | 1198 | printf "\t%s\t%s",$insn,join(",",map($_->out($sz),@args)); |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 1199 | } |
| 1200 | } else { |
| 1201 | printf "\t%s",$opcode->out(); |
| 1202 | } |
| 1203 | } |
| 1204 | |
| 1205 | print $line,"\n"; |
| 1206 | } |
| 1207 | |
| 1208 | print "\n$current_segment\tENDS\n" if ($current_segment && $masm); |
| 1209 | print "END\n" if ($masm); |
| 1210 | print "#endif\n" if ($gas); |
| 1211 | |
| 1212 | |
| 1213 | close STDOUT; |
| 1214 | |
| 1215 | ################################################# |
| 1216 | # Cross-reference x86_64 ABI "card" |
| 1217 | # |
| 1218 | # Unix Win64 |
| 1219 | # %rax * * |
| 1220 | # %rbx - - |
| 1221 | # %rcx #4 #1 |
| 1222 | # %rdx #3 #2 |
| 1223 | # %rsi #2 - |
| 1224 | # %rdi #1 - |
| 1225 | # %rbp - - |
| 1226 | # %rsp - - |
| 1227 | # %r8 #5 #3 |
| 1228 | # %r9 #6 #4 |
| 1229 | # %r10 * * |
| 1230 | # %r11 * * |
| 1231 | # %r12 - - |
| 1232 | # %r13 - - |
| 1233 | # %r14 - - |
| 1234 | # %r15 - - |
Robert Sloan | a94fe05 | 2017-02-21 08:49:28 -0800 | [diff] [blame] | 1235 | # |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 1236 | # (*) volatile register |
| 1237 | # (-) preserved by callee |
| 1238 | # (#) Nth argument, volatile |
| 1239 | # |
| 1240 | # In Unix terms top of stack is argument transfer area for arguments |
David Benjamin | c895d6b | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 1241 | # which could not be accommodated in registers. Or in other words 7th |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 1242 | # [integer] argument resides at 8(%rsp) upon function entry point. |
| 1243 | # 128 bytes above %rsp constitute a "red zone" which is not touched |
| 1244 | # by signal handlers and can be used as temporal storage without |
| 1245 | # allocating a frame. |
| 1246 | # |
| 1247 | # In Win64 terms N*8 bytes on top of stack is argument transfer area, |
| 1248 | # which belongs to/can be overwritten by callee. N is the number of |
| 1249 | # arguments passed to callee, *but* not less than 4! This means that |
| 1250 | # upon function entry point 5th argument resides at 40(%rsp), as well |
| 1251 | # as that 32 bytes from 8(%rsp) can always be used as temporal |
| 1252 | # storage [without allocating a frame]. One can actually argue that |
| 1253 | # one can assume a "red zone" above stack pointer under Win64 as well. |
| 1254 | # Point is that at apparently no occasion Windows kernel would alter |
| 1255 | # the area above user stack pointer in true asynchronous manner... |
| 1256 | # |
| 1257 | # All the above means that if assembler programmer adheres to Unix |
Robert Sloan | a94fe05 | 2017-02-21 08:49:28 -0800 | [diff] [blame] | 1258 | # register and stack layout, but disregards the "red zone" existence, |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 1259 | # it's possible to use following prologue and epilogue to "gear" from |
| 1260 | # Unix to Win64 ABI in leaf functions with not more than 6 arguments. |
| 1261 | # |
| 1262 | # omnipotent_function: |
| 1263 | # ifdef WIN64 |
| 1264 | # movq %rdi,8(%rsp) |
| 1265 | # movq %rsi,16(%rsp) |
| 1266 | # movq %rcx,%rdi ; if 1st argument is actually present |
| 1267 | # movq %rdx,%rsi ; if 2nd argument is actually ... |
| 1268 | # movq %r8,%rdx ; if 3rd argument is ... |
| 1269 | # movq %r9,%rcx ; if 4th argument ... |
| 1270 | # movq 40(%rsp),%r8 ; if 5th ... |
| 1271 | # movq 48(%rsp),%r9 ; if 6th ... |
| 1272 | # endif |
| 1273 | # ... |
| 1274 | # ifdef WIN64 |
| 1275 | # movq 8(%rsp),%rdi |
| 1276 | # movq 16(%rsp),%rsi |
| 1277 | # endif |
| 1278 | # ret |
| 1279 | # |
| 1280 | ################################################# |
| 1281 | # Win64 SEH, Structured Exception Handling. |
| 1282 | # |
| 1283 | # Unlike on Unix systems(*) lack of Win64 stack unwinding information |
| 1284 | # has undesired side-effect at run-time: if an exception is raised in |
| 1285 | # assembler subroutine such as those in question (basically we're |
| 1286 | # referring to segmentation violations caused by malformed input |
| 1287 | # parameters), the application is briskly terminated without invoking |
| 1288 | # any exception handlers, most notably without generating memory dump |
| 1289 | # or any user notification whatsoever. This poses a problem. It's |
| 1290 | # possible to address it by registering custom language-specific |
| 1291 | # handler that would restore processor context to the state at |
| 1292 | # subroutine entry point and return "exception is not handled, keep |
| 1293 | # unwinding" code. Writing such handler can be a challenge... But it's |
| 1294 | # doable, though requires certain coding convention. Consider following |
| 1295 | # snippet: |
| 1296 | # |
| 1297 | # .type function,@function |
| 1298 | # function: |
| 1299 | # movq %rsp,%rax # copy rsp to volatile register |
| 1300 | # pushq %r15 # save non-volatile registers |
| 1301 | # pushq %rbx |
| 1302 | # pushq %rbp |
| 1303 | # movq %rsp,%r11 |
| 1304 | # subq %rdi,%r11 # prepare [variable] stack frame |
| 1305 | # andq $-64,%r11 |
| 1306 | # movq %rax,0(%r11) # check for exceptions |
| 1307 | # movq %r11,%rsp # allocate [variable] stack frame |
| 1308 | # movq %rax,0(%rsp) # save original rsp value |
| 1309 | # magic_point: |
| 1310 | # ... |
| 1311 | # movq 0(%rsp),%rcx # pull original rsp value |
| 1312 | # movq -24(%rcx),%rbp # restore non-volatile registers |
| 1313 | # movq -16(%rcx),%rbx |
| 1314 | # movq -8(%rcx),%r15 |
| 1315 | # movq %rcx,%rsp # restore original rsp |
Robert Sloan | 5d62578 | 2017-02-13 09:55:39 -0800 | [diff] [blame] | 1316 | # magic_epilogue: |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 1317 | # ret |
| 1318 | # .size function,.-function |
| 1319 | # |
| 1320 | # The key is that up to magic_point copy of original rsp value remains |
| 1321 | # in chosen volatile register and no non-volatile register, except for |
| 1322 | # rsp, is modified. While past magic_point rsp remains constant till |
| 1323 | # the very end of the function. In this case custom language-specific |
| 1324 | # exception handler would look like this: |
| 1325 | # |
| 1326 | # EXCEPTION_DISPOSITION handler (EXCEPTION_RECORD *rec,ULONG64 frame, |
| 1327 | # CONTEXT *context,DISPATCHER_CONTEXT *disp) |
| 1328 | # { ULONG64 *rsp = (ULONG64 *)context->Rax; |
Robert Sloan | 5d62578 | 2017-02-13 09:55:39 -0800 | [diff] [blame] | 1329 | # ULONG64 rip = context->Rip; |
| 1330 | # |
| 1331 | # if (rip >= magic_point) |
| 1332 | # { rsp = (ULONG64 *)context->Rsp; |
| 1333 | # if (rip < magic_epilogue) |
| 1334 | # { rsp = (ULONG64 *)rsp[0]; |
| 1335 | # context->Rbp = rsp[-3]; |
| 1336 | # context->Rbx = rsp[-2]; |
| 1337 | # context->R15 = rsp[-1]; |
| 1338 | # } |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 1339 | # } |
| 1340 | # context->Rsp = (ULONG64)rsp; |
| 1341 | # context->Rdi = rsp[1]; |
| 1342 | # context->Rsi = rsp[2]; |
| 1343 | # |
| 1344 | # memcpy (disp->ContextRecord,context,sizeof(CONTEXT)); |
| 1345 | # RtlVirtualUnwind(UNW_FLAG_NHANDLER,disp->ImageBase, |
| 1346 | # dips->ControlPc,disp->FunctionEntry,disp->ContextRecord, |
| 1347 | # &disp->HandlerData,&disp->EstablisherFrame,NULL); |
| 1348 | # return ExceptionContinueSearch; |
| 1349 | # } |
| 1350 | # |
| 1351 | # It's appropriate to implement this handler in assembler, directly in |
| 1352 | # function's module. In order to do that one has to know members' |
| 1353 | # offsets in CONTEXT and DISPATCHER_CONTEXT structures and some constant |
| 1354 | # values. Here they are: |
| 1355 | # |
| 1356 | # CONTEXT.Rax 120 |
| 1357 | # CONTEXT.Rcx 128 |
| 1358 | # CONTEXT.Rdx 136 |
| 1359 | # CONTEXT.Rbx 144 |
| 1360 | # CONTEXT.Rsp 152 |
| 1361 | # CONTEXT.Rbp 160 |
| 1362 | # CONTEXT.Rsi 168 |
| 1363 | # CONTEXT.Rdi 176 |
| 1364 | # CONTEXT.R8 184 |
| 1365 | # CONTEXT.R9 192 |
| 1366 | # CONTEXT.R10 200 |
| 1367 | # CONTEXT.R11 208 |
| 1368 | # CONTEXT.R12 216 |
| 1369 | # CONTEXT.R13 224 |
| 1370 | # CONTEXT.R14 232 |
| 1371 | # CONTEXT.R15 240 |
| 1372 | # CONTEXT.Rip 248 |
| 1373 | # CONTEXT.Xmm6 512 |
| 1374 | # sizeof(CONTEXT) 1232 |
| 1375 | # DISPATCHER_CONTEXT.ControlPc 0 |
| 1376 | # DISPATCHER_CONTEXT.ImageBase 8 |
| 1377 | # DISPATCHER_CONTEXT.FunctionEntry 16 |
| 1378 | # DISPATCHER_CONTEXT.EstablisherFrame 24 |
| 1379 | # DISPATCHER_CONTEXT.TargetIp 32 |
| 1380 | # DISPATCHER_CONTEXT.ContextRecord 40 |
| 1381 | # DISPATCHER_CONTEXT.LanguageHandler 48 |
| 1382 | # DISPATCHER_CONTEXT.HandlerData 56 |
| 1383 | # UNW_FLAG_NHANDLER 0 |
| 1384 | # ExceptionContinueSearch 1 |
| 1385 | # |
| 1386 | # In order to tie the handler to the function one has to compose |
| 1387 | # couple of structures: one for .xdata segment and one for .pdata. |
| 1388 | # |
| 1389 | # UNWIND_INFO structure for .xdata segment would be |
| 1390 | # |
| 1391 | # function_unwind_info: |
| 1392 | # .byte 9,0,0,0 |
| 1393 | # .rva handler |
| 1394 | # |
| 1395 | # This structure designates exception handler for a function with |
| 1396 | # zero-length prologue, no stack frame or frame register. |
| 1397 | # |
| 1398 | # To facilitate composing of .pdata structures, auto-generated "gear" |
| 1399 | # prologue copies rsp value to rax and denotes next instruction with |
| 1400 | # .LSEH_begin_{function_name} label. This essentially defines the SEH |
| 1401 | # styling rule mentioned in the beginning. Position of this label is |
| 1402 | # chosen in such manner that possible exceptions raised in the "gear" |
| 1403 | # prologue would be accounted to caller and unwound from latter's frame. |
| 1404 | # End of function is marked with respective .LSEH_end_{function_name} |
| 1405 | # label. To summarize, .pdata segment would contain |
| 1406 | # |
| 1407 | # .rva .LSEH_begin_function |
| 1408 | # .rva .LSEH_end_function |
| 1409 | # .rva function_unwind_info |
| 1410 | # |
David Benjamin | c895d6b | 2016-08-11 13:26:41 -0400 | [diff] [blame] | 1411 | # Reference to function_unwind_info from .xdata segment is the anchor. |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 1412 | # In case you wonder why references are 32-bit .rvas and not 64-bit |
| 1413 | # .quads. References put into these two segments are required to be |
| 1414 | # *relative* to the base address of the current binary module, a.k.a. |
| 1415 | # image base. No Win64 module, be it .exe or .dll, can be larger than |
| 1416 | # 2GB and thus such relative references can be and are accommodated in |
| 1417 | # 32 bits. |
| 1418 | # |
| 1419 | # Having reviewed the example function code, one can argue that "movq |
| 1420 | # %rsp,%rax" above is redundant. It is not! Keep in mind that on Unix |
| 1421 | # rax would contain an undefined value. If this "offends" you, use |
| 1422 | # another register and refrain from modifying rax till magic_point is |
| 1423 | # reached, i.e. as if it was a non-volatile register. If more registers |
| 1424 | # are required prior [variable] frame setup is completed, note that |
| 1425 | # nobody says that you can have only one "magic point." You can |
| 1426 | # "liberate" non-volatile registers by denoting last stack off-load |
| 1427 | # instruction and reflecting it in finer grade unwind logic in handler. |
| 1428 | # After all, isn't it why it's called *language-specific* handler... |
| 1429 | # |
Robert Sloan | 5d62578 | 2017-02-13 09:55:39 -0800 | [diff] [blame] | 1430 | # SE handlers are also involved in unwinding stack when executable is |
| 1431 | # profiled or debugged. Profiling implies additional limitations that |
| 1432 | # are too subtle to discuss here. For now it's sufficient to say that |
| 1433 | # in order to simplify handlers one should either a) offload original |
| 1434 | # %rsp to stack (like discussed above); or b) if you have a register to |
| 1435 | # spare for frame pointer, choose volatile one. |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 1436 | # |
| 1437 | # (*) Note that we're talking about run-time, not debug-time. Lack of |
| 1438 | # unwind information makes debugging hard on both Windows and |
Robert Sloan | ab8b888 | 2018-03-26 11:39:51 -0700 | [diff] [blame^] | 1439 | # Unix. "Unlike" refers to the fact that on Unix signal handler |
Adam Langley | d9e397b | 2015-01-22 14:27:53 -0800 | [diff] [blame] | 1440 | # will always be invoked, core dumped and appropriate exit code |
| 1441 | # returned to parent (for user notification). |