1#!/usr/bin/env ruby
2
3# Copyright (C) 2011 Apple Inc. All rights reserved.
4#
5# Redistribution and use in source and binary forms, with or without
6# modification, are permitted provided that the following conditions
7# are met:
8# 1. Redistributions of source code must retain the above copyright
9#    notice, this list of conditions and the following disclaimer.
10# 2. Redistributions in binary form must reproduce the above copyright
11#    notice, this list of conditions and the following disclaimer in the
12#    documentation and/or other materials provided with the distribution.
13#
14# THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS''
15# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
16# THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
17# PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS
18# BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
19# CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
20# SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
21# INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
22# CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
23# ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
24# THE POSSIBILITY OF SUCH DAMAGE.
25
26$: << File.dirname(__FILE__)
27
28require "config"
29require "backends"
30require "digest/sha1"
31require "offsets"
32require "parser"
33require "self_hash"
34require "settings"
35require "transform"
36
37inputFlnm = ARGV.shift
38outputFlnm = ARGV.shift
39
40$stderr.puts "offlineasm: Parsing #{inputFlnm} and creating offset extractor #{outputFlnm}."
41
42def emitMagicNumber
43    OFFSET_MAGIC_NUMBERS.each {
44        | number |
45        $output.puts "unsigned(#{number}),"
46    }
47end
48
49inputHash = "// offlineasm input hash: #{parseHash(inputFlnm)} #{selfHash}"
50
51if FileTest.exist? outputFlnm
52    File.open(outputFlnm, "r") {
53        | inp |
54        firstLine = inp.gets
55        if firstLine and firstLine.chomp == inputHash
56            $stderr.puts "offlineasm: Nothing changed."
57            exit 0
58        end
59    }
60end
61
62originalAST = parse(inputFlnm)
63
64#
65# Optimize the AST to make configuration extraction faster. This reduces the AST to a form
66# that only contains the things that matter for our purposes: offsets, sizes, and if
67# statements.
68#
69
70class Node
71    def offsetsPruneTo(sequence)
72        children.each {
73            | child |
74            child.offsetsPruneTo(sequence)
75        }
76    end
77    
78    def offsetsPrune
79        result = Sequence.new(codeOrigin, [])
80        offsetsPruneTo(result)
81        result
82    end
83end
84
85class IfThenElse
86    def offsetsPruneTo(sequence)
87        ifThenElse = IfThenElse.new(codeOrigin, predicate, thenCase.offsetsPrune)
88        ifThenElse.elseCase = elseCase.offsetsPrune
89        sequence.list << ifThenElse
90    end
91end
92
93class StructOffset
94    def offsetsPruneTo(sequence)
95        sequence.list << self
96    end
97end
98
99class Sizeof
100    def offsetsPruneTo(sequence)
101        sequence.list << self
102    end
103end
104
105prunedAST = originalAST.offsetsPrune
106
107File.open(outputFlnm, "w") {
108    | outp |
109    $output = outp
110    outp.puts inputHash
111    length = 0
112    emitCodeInAllConfigurations(prunedAST) {
113        | settings, ast, backend, index |
114        offsetsList = ast.filter(StructOffset).uniq.sort
115        sizesList = ast.filter(Sizeof).uniq.sort
116        length += OFFSET_HEADER_MAGIC_NUMBERS.size + (OFFSET_MAGIC_NUMBERS.size + 1) * (1 + offsetsList.size + sizesList.size)
117    }
118    outp.puts "static const unsigned extractorTable[#{length}] = {"
119    emitCodeInAllConfigurations(prunedAST) {
120        | settings, ast, backend, index |
121        OFFSET_HEADER_MAGIC_NUMBERS.each {
122            | number |
123            $output.puts "unsigned(#{number}),"
124        }
125
126        offsetsList = ast.filter(StructOffset).uniq.sort
127        sizesList = ast.filter(Sizeof).uniq.sort
128        
129        emitMagicNumber
130        outp.puts "#{index},"
131        offsetsList.each {
132            | offset |
133            emitMagicNumber
134            outp.puts "OFFLINE_ASM_OFFSETOF(#{offset.struct}, #{offset.field}),"
135        }
136        sizesList.each {
137            | offset |
138            emitMagicNumber
139            outp.puts "sizeof(#{offset.struct}),"
140        }
141    }
142    outp.puts "};"
143}
144
145$stderr.puts "offlineasm: offset extractor #{outputFlnm} successfully generated."
146
147