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authormarha <marha@users.sourceforge.net>2009-06-28 22:07:26 +0000
committermarha <marha@users.sourceforge.net>2009-06-28 22:07:26 +0000
commit3562e78743202e43aec8727005182a2558117eca (patch)
tree8f9113a77d12470c5c851a2a8e4cb02e89df7d43 /openssl/crypto/perlasm/x86_64-xlate.pl
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Checked in the following released items:
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Diffstat (limited to 'openssl/crypto/perlasm/x86_64-xlate.pl')
-rw-r--r--openssl/crypto/perlasm/x86_64-xlate.pl554
1 files changed, 554 insertions, 0 deletions
diff --git a/openssl/crypto/perlasm/x86_64-xlate.pl b/openssl/crypto/perlasm/x86_64-xlate.pl
new file mode 100644
index 000000000..a4af769b4
--- /dev/null
+++ b/openssl/crypto/perlasm/x86_64-xlate.pl
@@ -0,0 +1,554 @@
+#!/usr/bin/env perl
+
+# Ascetic x86_64 AT&T to MASM assembler translator by <appro>.
+#
+# Why AT&T to MASM and not vice versa? Several reasons. Because AT&T
+# format is way easier to parse. Because it's simpler to "gear" from
+# Unix ABI to Windows one [see cross-reference "card" at the end of
+# file]. Because Linux targets were available first...
+#
+# In addition the script also "distills" code suitable for GNU
+# assembler, so that it can be compiled with more rigid assemblers,
+# such as Solaris /usr/ccs/bin/as.
+#
+# This translator is not designed to convert *arbitrary* assembler
+# code from AT&T format to MASM one. It's designed to convert just
+# enough to provide for dual-ABI OpenSSL modules development...
+# There *are* limitations and you might have to modify your assembler
+# code or this script to achieve the desired result...
+#
+# Currently recognized limitations:
+#
+# - can't use multiple ops per line;
+# - indirect calls and jumps are not supported;
+#
+# Dual-ABI styling rules.
+#
+# 1. Adhere to Unix register and stack layout [see the end for
+# explanation].
+# 2. Forget about "red zone," stick to more traditional blended
+# stack frame allocation. If volatile storage is actually required
+# that is. If not, just leave the stack as is.
+# 3. Functions tagged with ".type name,@function" get crafted with
+# unified Win64 prologue and epilogue automatically. If you want
+# to take care of ABI differences yourself, tag functions as
+# ".type name,@abi-omnipotent" instead.
+# 4. To optimize the Win64 prologue you can specify number of input
+# arguments as ".type name,@function,N." Keep in mind that if N is
+# larger than 6, then you *have to* write "abi-omnipotent" code,
+# because >6 cases can't be addressed with unified prologue.
+# 5. Name local labels as .L*, do *not* use dynamic labels such as 1:
+# (sorry about latter).
+# 6. Don't use [or hand-code with .byte] "rep ret." "ret" mnemonic is
+# required to identify the spots, where to inject Win64 epilogue!
+# But on the pros, it's then prefixed with rep automatically:-)
+# 7. Due to MASM limitations [and certain general counter-intuitivity
+# of ip-relative addressing] generation of position-independent
+# code is assisted by synthetic directive, .picmeup, which puts
+# address of the *next* instruction into target register.
+#
+# Example 1:
+# .picmeup %rax
+# lea .Label-.(%rax),%rax
+# Example 2:
+# .picmeup %rcx
+# .Lpic_point:
+# ...
+# lea .Label-.Lpic_point(%rcx),%rbp
+
+my $output = shift;
+
+{ my ($stddev,$stdino,@junk)=stat(STDOUT);
+ my ($outdev,$outino,@junk)=stat($output);
+
+ open STDOUT,">$output" || die "can't open $output: $!"
+ if ($stddev!=$outdev || $stdino!=$outino);
+}
+
+my $masmref=8 + 50727*2**-32; # 8.00.50727 shipped with VS2005
+my $masm=$masmref if ($output =~ /\.asm/);
+if ($masm && `ml64 2>&1` =~ m/Version ([0-9]+)\.([0-9]+)(\.([0-9]+))?/)
+{ $masm=$1 + $2*2**-16 + $4*2**-32; }
+
+my $current_segment;
+my $current_function;
+
+{ package opcode; # pick up opcodes
+ sub re {
+ my $self = shift; # single instance in enough...
+ local *line = shift;
+ undef $ret;
+
+ if ($line =~ /^([a-z][a-z0-9]*)/i) {
+ $self->{op} = $1;
+ $ret = $self;
+ $line = substr($line,@+[0]); $line =~ s/^\s+//;
+
+ undef $self->{sz};
+ if ($self->{op} =~ /^(movz)b.*/) { # movz is pain...
+ $self->{op} = $1;
+ $self->{sz} = "b";
+ } elsif ($self->{op} =~ /call/) {
+ $self->{sz} = ""
+ } elsif ($self->{op} =~ /([a-z]{3,})([qlwb])$/) {
+ $self->{op} = $1;
+ $self->{sz} = $2;
+ }
+ }
+ $ret;
+ }
+ sub size {
+ my $self = shift;
+ my $sz = shift;
+ $self->{sz} = $sz if (defined($sz) && !defined($self->{sz}));
+ $self->{sz};
+ }
+ sub out {
+ my $self = shift;
+ if (!$masm) {
+ if ($self->{op} eq "movz") { # movz is pain...
+ sprintf "%s%s%s",$self->{op},$self->{sz},shift;
+ } elsif ($self->{op} =~ /^set/) {
+ "$self->{op}";
+ } elsif ($self->{op} eq "ret") {
+ ".byte 0xf3,0xc3";
+ } else {
+ "$self->{op}$self->{sz}";
+ }
+ } else {
+ $self->{op} =~ s/^movz/movzx/;
+ if ($self->{op} eq "ret") {
+ $self->{op} = "";
+ if ($current_function->{abi} eq "svr4") {
+ $self->{op} = "mov rdi,QWORD PTR 8[rsp]\t;WIN64 epilogue\n\t".
+ "mov rsi,QWORD PTR 16[rsp]\n\t";
+ }
+ $self->{op} .= "DB\t0F3h,0C3h\t\t;repret";
+ }
+ $self->{op};
+ }
+ }
+}
+{ package const; # pick up constants, which start with $
+ sub re {
+ my $self = shift; # single instance in enough...
+ local *line = shift;
+ undef $ret;
+
+ if ($line =~ /^\$([^,]+)/) {
+ $self->{value} = $1;
+ $ret = $self;
+ $line = substr($line,@+[0]); $line =~ s/^\s+//;
+ }
+ $ret;
+ }
+ sub out {
+ my $self = shift;
+
+ if (!$masm) {
+ # Solaris /usr/ccs/bin/as can't handle multiplications
+ # in $self->{value}
+ $self->{value} =~ s/(?<![0-9a-f])(0[x0-9a-f]+)/oct($1)/egi;
+ $self->{value} =~ s/([0-9]+\s*[\*\/\%]\s*[0-9]+)/eval($1)/eg;
+ sprintf "\$%s",$self->{value};
+ } else {
+ $self->{value} =~ s/0x([0-9a-f]+)/0$1h/ig;
+ sprintf "%s",$self->{value};
+ }
+ }
+}
+{ package ea; # pick up effective addresses: expr(%reg,%reg,scale)
+ sub re {
+ my $self = shift; # single instance in enough...
+ local *line = shift;
+ undef $ret;
+
+ if ($line =~ /^([^\(,]*)\(([%\w,]+)\)/) {
+ $self->{label} = $1;
+ ($self->{base},$self->{index},$self->{scale})=split(/,/,$2);
+ $self->{scale} = 1 if (!defined($self->{scale}));
+ $ret = $self;
+ $line = substr($line,@+[0]); $line =~ s/^\s+//;
+
+ $self->{base} =~ s/^%//;
+ $self->{index} =~ s/^%// if (defined($self->{index}));
+ }
+ $ret;
+ }
+ sub size {}
+ sub out {
+ my $self = shift;
+ my $sz = shift;
+
+ # Silently convert all EAs to 64-bit. This is required for
+ # elder GNU assembler and results in more compact code,
+ # *but* most importantly AES module depends on this feature!
+ $self->{index} =~ s/^[er](.?[0-9xpi])[d]?$/r\1/;
+ $self->{base} =~ s/^[er](.?[0-9xpi])[d]?$/r\1/;
+
+ if (!$masm) {
+ # Solaris /usr/ccs/bin/as can't handle multiplications
+ # in $self->{label}
+ $self->{label} =~ s/(?<![0-9a-f])(0[x0-9a-f]+)/oct($1)/egi;
+ $self->{label} =~ s/([0-9]+\s*[\*\/\%]\s*[0-9]+)/eval($1)/eg;
+
+ if (defined($self->{index})) {
+ sprintf "%s(%%%s,%%%s,%d)",
+ $self->{label},$self->{base},
+ $self->{index},$self->{scale};
+ } else {
+ sprintf "%s(%%%s)", $self->{label},$self->{base};
+ }
+ } else {
+ %szmap = ( b=>"BYTE", w=>"WORD", l=>"DWORD", q=>"QWORD" );
+
+ $self->{label} =~ s/\./\$/g;
+ $self->{label} =~ s/0x([0-9a-f]+)/0$1h/ig;
+ $self->{label} = "($self->{label})" if ($self->{label} =~ /[\*\+\-\/]/);
+
+ if (defined($self->{index})) {
+ sprintf "%s PTR %s[%s*%d+%s]",$szmap{$sz},
+ $self->{label},
+ $self->{index},$self->{scale},
+ $self->{base};
+ } elsif ($self->{base} eq "rip") {
+ sprintf "%s PTR %s",$szmap{$sz},$self->{label};
+ } else {
+ sprintf "%s PTR %s[%s]",$szmap{$sz},
+ $self->{label},$self->{base};
+ }
+ }
+ }
+}
+{ package register; # pick up registers, which start with %.
+ sub re {
+ my $class = shift; # muliple instances...
+ my $self = {};
+ local *line = shift;
+ undef $ret;
+
+ if ($line =~ /^%(\w+)/) {
+ bless $self,$class;
+ $self->{value} = $1;
+ $ret = $self;
+ $line = substr($line,@+[0]); $line =~ s/^\s+//;
+ }
+ $ret;
+ }
+ sub size {
+ my $self = shift;
+ undef $ret;
+
+ if ($self->{value} =~ /^r[\d]+b$/i) { $ret="b"; }
+ elsif ($self->{value} =~ /^r[\d]+w$/i) { $ret="w"; }
+ elsif ($self->{value} =~ /^r[\d]+d$/i) { $ret="l"; }
+ elsif ($self->{value} =~ /^r[\w]+$/i) { $ret="q"; }
+ elsif ($self->{value} =~ /^[a-d][hl]$/i){ $ret="b"; }
+ elsif ($self->{value} =~ /^[\w]{2}l$/i) { $ret="b"; }
+ elsif ($self->{value} =~ /^[\w]{2}$/i) { $ret="w"; }
+ elsif ($self->{value} =~ /^e[a-z]{2}$/i){ $ret="l"; }
+
+ $ret;
+ }
+ sub out {
+ my $self = shift;
+ sprintf $masm?"%s":"%%%s",$self->{value};
+ }
+}
+{ package label; # pick up labels, which end with :
+ sub re {
+ my $self = shift; # single instance is enough...
+ local *line = shift;
+ undef $ret;
+
+ if ($line =~ /(^[\.\w]+\:)/) {
+ $self->{value} = $1;
+ $ret = $self;
+ $line = substr($line,@+[0]); $line =~ s/^\s+//;
+
+ $self->{value} =~ s/\.L/\$L/ if ($masm);
+ }
+ $ret;
+ }
+ sub out {
+ my $self = shift;
+
+ if (!$masm) {
+ $self->{value};
+ } elsif ($self->{value} ne "$current_function->{name}:") {
+ $self->{value};
+ } elsif ($current_function->{abi} eq "svr4") {
+ my $func = "$current_function->{name} PROC\n".
+ " mov QWORD PTR 8[rsp],rdi\t;WIN64 prologue\n".
+ " mov QWORD PTR 16[rsp],rsi\n";
+ my $narg = $current_function->{narg};
+ $narg=6 if (!defined($narg));
+ $func .= " mov rdi,rcx\n" if ($narg>0);
+ $func .= " mov rsi,rdx\n" if ($narg>1);
+ $func .= " mov rdx,r8\n" if ($narg>2);
+ $func .= " mov rcx,r9\n" if ($narg>3);
+ $func .= " mov r8,QWORD PTR 40[rsp]\n" if ($narg>4);
+ $func .= " mov r9,QWORD PTR 48[rsp]\n" if ($narg>5);
+ $func .= "\n";
+ } else {
+ "$current_function->{name} PROC";
+ }
+ }
+}
+{ package expr; # pick up expressioins
+ sub re {
+ my $self = shift; # single instance is enough...
+ local *line = shift;
+ undef $ret;
+
+ if ($line =~ /(^[^,]+)/) {
+ $self->{value} = $1;
+ $ret = $self;
+ $line = substr($line,@+[0]); $line =~ s/^\s+//;
+
+ $self->{value} =~ s/\.L/\$L/g if ($masm);
+ }
+ $ret;
+ }
+ sub out {
+ my $self = shift;
+ $self->{value};
+ }
+}
+{ package directive; # pick up directives, which start with .
+ sub re {
+ my $self = shift; # single instance is enough...
+ local *line = shift;
+ undef $ret;
+ my $dir;
+ my %opcode = # lea 2f-1f(%rip),%dst; 1: nop; 2:
+ ( "%rax"=>0x01058d48, "%rcx"=>0x010d8d48,
+ "%rdx"=>0x01158d48, "%rbx"=>0x011d8d48,
+ "%rsp"=>0x01258d48, "%rbp"=>0x012d8d48,
+ "%rsi"=>0x01358d48, "%rdi"=>0x013d8d48,
+ "%r8" =>0x01058d4c, "%r9" =>0x010d8d4c,
+ "%r10"=>0x01158d4c, "%r11"=>0x011d8d4c,
+ "%r12"=>0x01258d4c, "%r13"=>0x012d8d4c,
+ "%r14"=>0x01358d4c, "%r15"=>0x013d8d4c );
+
+ if ($line =~ /^\s*(\.\w+)/) {
+ if (!$masm) {
+ $self->{value} = $1;
+ $line =~ s/\@abi\-omnipotent/\@function/;
+ $line =~ s/\@function.*/\@function/;
+ if ($line =~ /\.picmeup\s+(%r[\w]+)/i) {
+ $self->{value} = sprintf "\t.long\t0x%x,0x90000000",$opcode{$1};
+ } elsif ($line =~ /\.asciz\s+"(.*)"$/) {
+ $self->{value} = ".byte\t".join(",",unpack("C*",$1),0);
+ } elsif ($line =~ /\.extern/) {
+ $self->{value} = ""; # swallow extern
+ } else {
+ $self->{value} = $line;
+ }
+ $line = "";
+ return $self;
+ }
+
+ $dir = $1;
+ $ret = $self;
+ undef $self->{value};
+ $line = substr($line,@+[0]); $line =~ s/^\s+//;
+ SWITCH: for ($dir) {
+ /\.(text)/
+ && do { my $v=undef;
+ $v="$current_segment\tENDS\n" if ($current_segment);
+ $current_segment = "_$1\$";
+ $current_segment =~ tr/[a-z]/[A-Z]/;
+ $v.="$current_segment\tSEGMENT ";
+ $v.=$masm>=$masmref ? "ALIGN(64)" : "PAGE";
+ $v.=" 'CODE'";
+ $self->{value} = $v;
+ last;
+ };
+ /\.extern/ && do { $self->{value} = "EXTRN\t".$line.":BYTE"; last; };
+ /\.globl/ && do { $self->{value} = "PUBLIC\t".$line; last; };
+ /\.type/ && do { ($sym,$type,$narg) = split(',',$line);
+ if ($type eq "\@function") {
+ undef $current_function;
+ $current_function->{name} = $sym;
+ $current_function->{abi} = "svr4";
+ $current_function->{narg} = $narg;
+ } elsif ($type eq "\@abi-omnipotent") {
+ undef $current_function;
+ $current_function->{name} = $sym;
+ }
+ last;
+ };
+ /\.size/ && do { if (defined($current_function)) {
+ $self->{value}="$current_function->{name}\tENDP";
+ undef $current_function;
+ }
+ last;
+ };
+ /\.align/ && do { $self->{value} = "ALIGN\t".$line; last; };
+ /\.(byte|value|long|quad)/
+ && do { my @arr = split(',',$line);
+ my $sz = substr($1,0,1);
+ my $last = pop(@arr);
+ my $conv = sub { my $var=shift;
+ if ($var=~s/0x([0-9a-f]+)/0$1h/i) { $var; }
+ else { sprintf"0%Xh",$var; }
+ };
+
+ $sz =~ tr/bvlq/BWDQ/;
+ $self->{value} = "\tD$sz\t";
+ for (@arr) { $self->{value} .= &$conv($_).","; }
+ $self->{value} .= &$conv($last);
+ last;
+ };
+ /\.picmeup/ && do { $self->{value} = sprintf"\tDD\t 0%Xh,090000000h",$opcode{$line};
+ last;
+ };
+ /\.asciz/ && do { if ($line =~ /^"(.*)"$/) {
+ my @str=unpack("C*",$1);
+ push @str,0;
+ while ($#str>15) {
+ $self->{value}.="DB\t"
+ .join(",",@str[0..15])."\n";
+ foreach (0..15) { shift @str; }
+ }
+ $self->{value}.="DB\t"
+ .join(",",@str) if (@str);
+ }
+ last;
+ };
+ }
+ $line = "";
+ }
+
+ $ret;
+ }
+ sub out {
+ my $self = shift;
+ $self->{value};
+ }
+}
+
+while($line=<>) {
+
+ chomp($line);
+
+ $line =~ s|[#!].*$||; # get rid of asm-style comments...
+ $line =~ s|/\*.*\*/||; # ... and C-style comments...
+ $line =~ s|^\s+||; # ... and skip white spaces in beginning
+
+ undef $label;
+ undef $opcode;
+ undef $dst;
+ undef $src;
+ undef $sz;
+
+ if ($label=label->re(\$line)) { print $label->out(); }
+
+ if (directive->re(\$line)) {
+ printf "%s",directive->out();
+ } elsif ($opcode=opcode->re(\$line)) { ARGUMENT: {
+
+ if ($src=register->re(\$line)) { opcode->size($src->size()); }
+ elsif ($src=const->re(\$line)) { }
+ elsif ($src=ea->re(\$line)) { }
+ elsif ($src=expr->re(\$line)) { }
+
+ last ARGUMENT if ($line !~ /^,/);
+
+ $line = substr($line,1); $line =~ s/^\s+//;
+
+ if ($dst=register->re(\$line)) { opcode->size($dst->size()); }
+ elsif ($dst=const->re(\$line)) { }
+ elsif ($dst=ea->re(\$line)) { }
+
+ } # ARGUMENT:
+
+ $sz=opcode->size();
+
+ if (defined($dst)) {
+ if (!$masm) {
+ printf "\t%s\t%s,%s", $opcode->out($dst->size()),
+ $src->out($sz),$dst->out($sz);
+ } else {
+ printf "\t%s\t%s,%s", $opcode->out(),
+ $dst->out($sz),$src->out($sz);
+ }
+ } elsif (defined($src)) {
+ printf "\t%s\t%s",$opcode->out(),$src->out($sz);
+ } else {
+ printf "\t%s",$opcode->out();
+ }
+ }
+
+ print $line,"\n";
+}
+
+print "\n$current_segment\tENDS\nEND\n" if ($masm);
+
+close STDOUT;
+
+#################################################
+# Cross-reference x86_64 ABI "card"
+#
+# Unix Win64
+# %rax * *
+# %rbx - -
+# %rcx #4 #1
+# %rdx #3 #2
+# %rsi #2 -
+# %rdi #1 -
+# %rbp - -
+# %rsp - -
+# %r8 #5 #3
+# %r9 #6 #4
+# %r10 * *
+# %r11 * *
+# %r12 - -
+# %r13 - -
+# %r14 - -
+# %r15 - -
+#
+# (*) volatile register
+# (-) preserved by callee
+# (#) Nth argument, volatile
+#
+# In Unix terms top of stack is argument transfer area for arguments
+# which could not be accomodated in registers. Or in other words 7th
+# [integer] argument resides at 8(%rsp) upon function entry point.
+# 128 bytes above %rsp constitute a "red zone" which is not touched
+# by signal handlers and can be used as temporal storage without
+# allocating a frame.
+#
+# In Win64 terms N*8 bytes on top of stack is argument transfer area,
+# which belongs to/can be overwritten by callee. N is the number of
+# arguments passed to callee, *but* not less than 4! This means that
+# upon function entry point 5th argument resides at 40(%rsp), as well
+# as that 32 bytes from 8(%rsp) can always be used as temporal
+# storage [without allocating a frame]. One can actually argue that
+# one can assume a "red zone" above stack pointer under Win64 as well.
+# Point is that at apparently no occasion Windows kernel would alter
+# the area above user stack pointer in true asynchronous manner...
+#
+# All the above means that if assembler programmer adheres to Unix
+# register and stack layout, but disregards the "red zone" existense,
+# it's possible to use following prologue and epilogue to "gear" from
+# Unix to Win64 ABI in leaf functions with not more than 6 arguments.
+#
+# omnipotent_function:
+# ifdef WIN64
+# movq %rdi,8(%rsp)
+# movq %rsi,16(%rsp)
+# movq %rcx,%rdi ; if 1st argument is actually present
+# movq %rdx,%rsi ; if 2nd argument is actually ...
+# movq %r8,%rdx ; if 3rd argument is ...
+# movq %r9,%rcx ; if 4th argument ...
+# movq 40(%rsp),%r8 ; if 5th ...
+# movq 48(%rsp),%r9 ; if 6th ...
+# endif
+# ...
+# ifdef WIN64
+# movq 8(%rsp),%rdi
+# movq 16(%rsp),%rsi
+# endif
+# ret