xref: /openbsd-src/lib/libcrypto/perlasm/x86gas.pl (revision eda85684cdcfde70d84443a28caf40467d147bfc) 
1#!/usr/bin/env perl
2
3package x86gas;
4
5*out=\@::out;
6
7$::lbdecor=$::aout?"L":".L";		# local label decoration
8$nmdecor=($::aout or $::coff)?"_":"";	# external name decoration
9
10$initseg="";
11
12$align=16;
13$align=log($align)/log(2) if ($::aout);
14$com_start="#" if ($::aout or $::coff);
15
16sub opsize()
17{ my $reg=shift;
18    if    ($reg =~ m/^%e/o)		{ "l"; }
19    elsif ($reg =~ m/^%[a-d][hl]$/o)	{ "b"; }
20    elsif ($reg =~ m/^%[xm]/o)		{ undef; }
21    else				{ "w"; }
22}
23
24# swap arguments;
25# expand opcode with size suffix;
26# prefix numeric constants with $;
27sub ::generic
28{ my($opcode,@arg)=@_;
29  my($suffix,$dst,$src);
30
31    @arg=reverse(@arg);
32
33    for (@arg)
34    {	s/^(\*?)(e?[a-dsixphl]{2})$/$1%$2/o;	# gp registers
35	s/^([xy]?mm[0-7])$/%$1/o;		# xmm/mmx registers
36	s/^(\-?[0-9]+)$/\$$1/o;			# constants
37	s/^(\-?0x[0-9a-f]+)$/\$$1/o;		# constants
38    }
39
40    $dst = $arg[$#arg]		if ($#arg>=0);
41    $src = $arg[$#arg-1]	if ($#arg>=1);
42    if    ($dst =~ m/^%/o)	{ $suffix=&opsize($dst); }
43    elsif ($src =~ m/^%/o)	{ $suffix=&opsize($src); }
44    else			{ $suffix="l";           }
45    undef $suffix if ($dst =~ m/^%[xm]/o || $src =~ m/^%[xm]/o);
46
47    if ($#_==0)				{ &::emit($opcode);		}
48    elsif ($#_==1 && $opcode =~ m/^(call|clflush|j|loop|set)/o)
49					{ &::emit($opcode,@arg);	}
50    else				{ &::emit($opcode.$suffix,@arg);}
51
52  1;
53}
54#
55# opcodes not covered by ::generic above, mostly inconsistent namings...
56#
57sub ::movzx	{ &::movzb(@_);			}
58sub ::pushfd	{ &::pushfl;			}
59sub ::popfd	{ &::popfl;			}
60sub ::cpuid	{ &::emit(".byte\t0x0f,0xa2");	}
61sub ::rdtsc	{ &::emit(".byte\t0x0f,0x31");	}
62
63sub ::call	{ &::emit("call",(&::islabel($_[0]) or "$nmdecor$_[0]")); }
64sub ::call_ptr	{ &::generic("call","*$_[0]");	}
65sub ::jmp_ptr	{ &::generic("jmp","*$_[0]");	}
66
67*::bswap = sub	{ &::emit("bswap","%$_[0]");	} if (!$::i386);
68
69sub ::DWP
70{ my($addr,$reg1,$reg2,$idx)=@_;
71  my $ret="";
72
73    $addr =~ s/^\s+//;
74    # prepend global references with optional underscore
75    $addr =~ s/^([^\+\-0-9][^\+\-]*)/&::islabel($1) or "$nmdecor$1"/ige;
76
77    $reg1 = "%$reg1" if ($reg1);
78    $reg2 = "%$reg2" if ($reg2);
79
80    $ret .= $addr if (($addr ne "") && ($addr ne 0));
81
82    if ($reg2)
83    {	$idx!= 0 or $idx=1;
84	$ret .= "($reg1,$reg2,$idx)";
85    }
86    elsif ($reg1)
87    {	$ret .= "($reg1)";	}
88
89  $ret;
90}
91sub ::QWP	{ &::DWP(@_);	}
92sub ::BP	{ &::DWP(@_);	}
93sub ::WP	{ &::DWP(@_);	}
94sub ::BC	{ @_;		}
95sub ::DWC	{ @_;		}
96
97sub ::file
98{   push(@out,".file\t\"$_[0].s\"\n.text\n");	}
99
100sub ::function_begin_B
101{ my $func=shift;
102  my $global=($func !~ /^_/);
103  my $begin="${::lbdecor}_${func}_begin";
104
105    &::LABEL($func,$global?"$begin":"$nmdecor$func");
106    $func=$nmdecor.$func;
107
108    push(@out,".globl\t$func\n")	if ($global);
109    if ($::coff)
110    {	push(@out,".def\t$func;\t.scl\t".(3-$global).";\t.type\t32;\t.endef\n"); }
111    elsif (($::aout and !$::pic) or $::macosx)
112    { }
113    else
114    {	push(@out,".type	$func,\@function\n"); }
115    push(@out,".align\t$align\n");
116    push(@out,"$func:\n");
117    push(@out,"$begin:\n")		if ($global);
118    $::stack=4;
119}
120
121sub ::function_end_B
122{ my $func=shift;
123    push(@out,".size\t$nmdecor$func,.-".&::LABEL($func)."\n") if ($::elf);
124    $::stack=0;
125    &::wipe_labels();
126}
127
128sub ::comment
129	{
130	if (!defined($com_start) or $::elf)
131		{	# Regarding $::elf above...
132			# GNU and SVR4 as'es use different comment delimiters,
133		push(@out,"\n");	# so we just skip ELF comments...
134		return;
135		}
136	foreach (@_)
137		{
138		if (/^\s*$/)
139			{ push(@out,"\n"); }
140		else
141			{ push(@out,"\t$com_start $_ $com_end\n"); }
142		}
143	}
144
145sub ::external_label
146{   foreach(@_) { &::LABEL($_,$nmdecor.$_); }   }
147
148sub ::public_label
149{   push(@out,".globl\t".&::LABEL($_[0],$nmdecor.$_[0])."\n");   }
150
151sub ::file_end
152{   if ($::macosx)
153    {	if (%non_lazy_ptr)
154    	{   push(@out,".section __IMPORT,__pointers,non_lazy_symbol_pointers\n");
155	    foreach $i (keys %non_lazy_ptr)
156	    {	push(@out,"$non_lazy_ptr{$i}:\n.indirect_symbol\t$i\n.long\t0\n");   }
157	}
158    }
159    if (grep {/\b${nmdecor}OPENSSL_ia32cap_P\b/i} @out) {
160	push (@out, ".extern\t${nmdecor}OPENSSL_ia32cap_P\n");
161	push (@out, ".hidden\t${nmdecor}OPENSSL_ia32cap_P\n");
162    }
163    push(@out,$initseg) if ($initseg);
164}
165
166sub ::data_byte	{   push(@out,".byte\t".join(',',@_)."\n");   }
167sub ::data_short{   push(@out,".value\t".join(',',@_)."\n");  }
168sub ::data_word {   push(@out,".long\t".join(',',@_)."\n");   }
169
170sub ::align
171{ my $val=$_[0],$p2,$i;
172    if ($::aout)
173    {	for ($p2=0;$val!=0;$val>>=1) { $p2++; }
174	$val=$p2-1;
175	$val.=",0x90";
176    }
177    push(@out,".align\t$val\n");
178}
179
180#
181# PIC data access wrappers
182#
183# Usage:
184#   picsetup($base)
185#	- only allowed once per function (because of hardcoded label name),
186#	  sets up pic access, uses $base register as temporary
187#   picsymbol($dst, $sym, $base)
188#	- loads the address of symbol $sym into $dst with the help of $base
189#	  initialized by picsetup
190#   picadjust($sym, $base)
191#	- adjusts a code pointer read from a code_sym table with the help of
192#	  $base initialized by picsetup
193#   code_sym($sym)
194#	- emits a pointer to the given code symbol, relative to the GOT if
195#	  PIC. This pointer will need to be adjusted with picadjust above
196#	  before use.
197
198sub ::picsetup
199{ my($base)=@_;
200
201    if (($::pic && ($::openbsd || $::elf || $::aout)) || $::macosx)
202    {
203	&::call(&::label("PIC_setup"));
204	&::set_label("PIC_setup");
205	&::blindpop($base);
206	if ($::macosx)
207	{   my $indirect=&::static_label("$nmdecor$sym\$non_lazy_ptr");
208	    $non_lazy_ptr{"$nmdecor$sym"}=$indirect;
209	}
210    }
211}
212
213sub ::picsymbol
214{ my($dst,$sym,$base)=@_;
215
216    if (($::pic && ($::openbsd || $::elf || $::aout)) || $::macosx)
217    {
218	my $reflabel=&::label("PIC_setup");
219	if ($::macosx)
220	{   my $indirect=$non_lazy_ptr{"$nmdecor$sym"};
221	    &::mov($dst,&::DWP("$indirect-$reflabel",$base));
222	}
223	else
224	{   &::lea($dst,&::DWP("_GLOBAL_OFFSET_TABLE_+[.-$reflabel]",
225		$base));
226	    &::mov($dst,&::DWP("$sym\@GOT",$dst));
227	}
228    }
229    else
230    {	&::lea($dst,&::DWP($sym));	}
231}
232
233sub ::picadjust
234{ my($sym,$base)=@_;
235
236    if (($::pic && ($::openbsd || $::elf || $::aout)) || $::macosx)
237    {
238	my $reflabel=&::label("PIC_setup");
239	&::lea($sym,&::DWP("_GLOBAL_OFFSET_TABLE_+[.-$reflabel]",
240		$base,$sym));
241    }
242}
243
244sub ::code_sym
245{ my($sym)=@_;
246
247    if (($::pic && ($::openbsd || $::elf || $::aout)) || $::macosx)
248    {
249	$sym."\@GOTOFF";
250    }
251    else
252    {
253	$sym;
254    }
255}
256
257sub ::initseg
258{ my $f=$nmdecor.shift;
259
260    if ($::openbsd)
261    {	$initseg.=<<___;
262.section	.init
263PIC_PROLOGUE
264	call	PIC_PLT($f)
265PIC_EPILOGUE
266___
267    } elsif ($::android)
268    {	$initseg.=<<___;
269.section	.init_array
270.align	4
271.long	$f
272___
273    }
274    elsif ($::elf)
275    {	$initseg.=<<___;
276.section	.init
277	call	$f
278___
279    }
280    elsif ($::coff)
281    {   $initseg.=<<___;	# applies to both Cygwin and Mingw
282.section	.ctors
283.long	$f
284___
285    }
286    elsif ($::macosx)
287    {	$initseg.=<<___;
288.mod_init_func
289.align 2
290.long   $f
291___
292    }
293    elsif ($::aout)
294    {	my $ctor="${nmdecor}_GLOBAL_\$I\$$f";
295	$initseg.=".text\n";
296	$initseg.=".type	$ctor,\@function\n" if ($::pic);
297	$initseg.=<<___;	# OpenBSD way...
298.globl	$ctor
299.align	2
300$ctor:
301	jmp	$f
302___
303    }
304}
305
306sub ::dataseg
307{   push(@out,".data\n");   }
308
309sub ::rodataseg
310{   push(@out,".section .rodata\n");   }
311
312sub ::previous
313{   push(@out,".previous\n");   }
314
3151;
316