The Tor Browser: media/libvpx/build/make/ads2gas.pl@ac0c01689b40 (annotated)

media/libvpx/build/make/ads2gas.pl@ac0c01689b40 (annotated)

media/libvpx/build/make/ads2gas.pl

Thu, 15 Jan 2015 15:59:08 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Thu, 15 Jan 2015 15:59:08 +0100
branch: TOR_BUG_9701
changeset 10: ac0c01689b40
permissions: -rwxr-xr-x

Implement a real Private Browsing Mode condition by changing the API/ABI;
This solves Tor bug #9701, complying with disk avoidance documented in
https://www.torproject.org/projects/torbrowser/design/#disk-avoidance.

 #!/usr/bin/perl
 ##
 ##  Copyright (c) 2010 The WebM project authors. All Rights Reserved.
 ##
 ##  Use of this source code is governed by a BSD-style license
 ##  that can be found in the LICENSE file in the root of the source
 ##  tree. An additional intellectual property rights grant can be found
 ##  in the file PATENTS.  All contributing project authors may
 ##  be found in the AUTHORS file in the root of the source tree.
 ##
 # ads2gas.pl
 # Author: Eric Fung (efung (at) acm.org)
 #
 # Convert ARM Developer Suite 1.0.1 syntax assembly source to GNU as format
 #
 # Usage: cat inputfile | perl ads2gas.pl > outputfile
 #
 use FindBin;
 use lib $FindBin::Bin;
 use thumb;
 my $thumb = 0;
 foreach my $arg (@ARGV) {
     $thumb = 1 if ($arg eq "-thumb");
 }
 print "@ This file was created from a .asm file\n";
 print "@  using the ads2gas.pl script.\n";
 print "\t.equ DO1STROUNDING, 0\n";
 if ($thumb) {
     print "\t.syntax unified\n";
     print "\t.thumb\n";
 }
 # Stack of procedure names.
 @proc_stack = ();
 while (<STDIN>)
 {
     undef $comment;
     undef $line;
     $comment_char = ";";
     $comment_sub = "@";
     # Handle comments.
     if (/$comment_char/)
     {
       $comment = "";
       ($line, $comment) = /(.*?)$comment_char(.*)/;
       $_ = $line;
     }
     # Load and store alignment
     s/@/,:/g;
     # Hexadecimal constants prefaced by 0x
     s/#&/#0x/g;
     # Convert :OR: to |
     s/:OR:/ | /g;
     # Convert :AND: to &
     s/:AND:/ & /g;
     # Convert :NOT: to ~
     s/:NOT:/ ~ /g;
     # Convert :SHL: to <<
     s/:SHL:/ << /g;
     # Convert :SHR: to >>
     s/:SHR:/ >> /g;
     # Convert ELSE to .else
     s/\bELSE\b/.else/g;
     # Convert ENDIF to .endif
     s/\bENDIF\b/.endif/g;
     # Convert ELSEIF to .elseif
     s/\bELSEIF\b/.elseif/g;
     # Convert LTORG to .ltorg
     s/\bLTORG\b/.ltorg/g;
     # Convert endfunc to nothing.
     s/\bendfunc\b//ig;
     # Convert FUNCTION to nothing.
     s/\bFUNCTION\b//g;
     s/\bfunction\b//g;
     s/\bENTRY\b//g;
     s/\bMSARMASM\b/0/g;
     s/^\s+end\s+$//g;
     # Convert IF :DEF:to .if
     # gcc doesn't have the ability to do a conditional
     # if defined variable that is set by IF :DEF: on
     # armasm, so convert it to a normal .if and then
     # make sure to define a value elesewhere
     if (s/\bIF :DEF:\b/.if /g)
     {
         s/=/==/g;
     }
     # Convert IF to .if
     if (s/\bIF\b/.if/g)
     {
         s/=+/==/g;
     }
     # Convert INCLUDE to .INCLUDE "file"
     s/INCLUDE(\s*)(.*)$/.include $1\"$2\"/;
     # Code directive (ARM vs Thumb)
     s/CODE([0-9][0-9])/.code $1/;
     # No AREA required
     # But ALIGNs in AREA must be obeyed
     s/^\s*AREA.*ALIGN=([0-9])$/.text\n.p2align $1/;
     # If no ALIGN, strip the AREA and align to 4 bytes
     s/^\s*AREA.*$/.text\n.p2align 2/;
     # DCD to .word
     # This one is for incoming symbols
     s/DCD\s+\|(\w*)\|/.long $1/;
     # DCW to .short
     s/DCW\s+\|(\w*)\|/.short $1/;
     s/DCW(.*)/.short $1/;
     # Constants defined in scope
     s/DCD(.*)/.long $1/;
     s/DCB(.*)/.byte $1/;
     # RN to .req
     if (s/RN\s+([Rr]\d+|lr)/.req $1/)
     {
         print;
         print "$comment_sub$comment\n" if defined $comment;
         next;
     }
     # Make function visible to linker, and make additional symbol with
     # prepended underscore
     s/EXPORT\s+\|([\$\w]*)\|/.global $1 \n\t.type $1, function/;
     s/IMPORT\s+\|([\$\w]*)\|/.global $1/;
     s/EXPORT\s+([\$\w]*)/.global $1/;
     s/export\s+([\$\w]*)/.global $1/;
     # No vertical bars required; make additional symbol with prepended
     # underscore
     s/^\|(\$?\w+)\|/_$1\n\t$1:/g;
     # Labels need trailing colon
 #   s/^(\w+)/$1:/ if !/EQU/;
     # put the colon at the end of the line in the macro
     s/^([a-zA-Z_0-9\$]+)/$1:/ if !/EQU/;
     # ALIGN directive
     s/\bALIGN\b/.balign/g;
     if ($thumb) {
         # ARM code - we force everything to thumb with the declaration in the header
         s/\sARM//g;
     } else {
         # ARM code
         s/\sARM/.arm/g;
     }
     # push/pop
     s/(push\s+)(r\d+)/stmdb sp\!, \{$2\}/g;
     s/(pop\s+)(r\d+)/ldmia sp\!, \{$2\}/g;
     # NEON code
     s/(vld1.\d+\s+)(q\d+)/$1\{$2\}/g;
     s/(vtbl.\d+\s+[^,]+),([^,]+)/$1,\{$2\}/g;
     if ($thumb) {
         thumb::FixThumbInstructions($_, 0);
     }
     # eabi_attributes numerical equivalents can be found in the
     # "ARM IHI 0045C" document.
     # REQUIRE8 Stack is required to be 8-byte aligned
     s/\sREQUIRE8/.eabi_attribute 24, 1 \@Tag_ABI_align_needed/g;
     # PRESERVE8 Stack 8-byte align is preserved
     s/\sPRESERVE8/.eabi_attribute 25, 1 \@Tag_ABI_align_preserved/g;
     # Use PROC and ENDP to give the symbols a .size directive.
     # This makes them show up properly in debugging tools like gdb and valgrind.
     if (/\bPROC\b/)
     {
         my $proc;
         /^_([\.0-9A-Z_a-z]\w+)\b/;
         $proc = $1;
         push(@proc_stack, $proc) if ($proc);
         s/\bPROC\b/@ $&/;
     }
     if (/\bENDP\b/)
     {
         my $proc;
         s/\bENDP\b/@ $&/;
         $proc = pop(@proc_stack);
         $_ = "\t.size $proc, .-$proc".$_ if ($proc);
     }
     # EQU directive
     s/(\S+\s+)EQU(\s+\S+)/.equ $1, $2/;
     # Begin macro definition
     if (/\bMACRO\b/) {
         $_ = <STDIN>;
         s/^/.macro/;
         s/\$//g;                # remove formal param reference
         s/;/@/g;                # change comment characters
     }
     # For macros, use \ to reference formal params
     s/\$/\\/g;                  # End macro definition
     s/\bMEND\b/.endm/;              # No need to tell it where to stop assembling
     next if /^\s*END\s*$/;
     print;
     print "$comment_sub$comment\n" if defined $comment;
 }
 # Mark that this object doesn't need an executable stack.
 printf ("\t.section\t.note.GNU-stack,\"\",\%\%progbits\n");

The Tor Browser / annotate

media/libvpx/build/make/ads2gas.pl@ac0c01689b40 (annotated)

media/libvpx/build/make/ads2gas.pl