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$: << File.dirname(__FILE__)
27
28require "config"
29require "backends"
30require "digest/sha1"
31require "offsets"
32require "parser"
33require "self_hash"
34require "settings"
35require "transform"
36
37IncludeFile.processIncludeOptions()
38
39inputFlnm = ARGV.shift
40outputFlnm = ARGV.shift
41
42$stderr.puts "offlineasm: Parsing #{inputFlnm} and creating offset extractor #{outputFlnm}."
43
44def emitMagicNumber
45    OFFSET_MAGIC_NUMBERS.each {
46        | number |
47        $output.puts "unsigned(#{number}),"
48    }
49end
50
51inputHash = "// offlineasm input hash: #{parseHash(inputFlnm)} #{selfHash}"
52
53if FileTest.exist? outputFlnm
54    File.open(outputFlnm, "r") {
55        | inp |
56        firstLine = inp.gets
57        if firstLine and firstLine.chomp == inputHash
58            $stderr.puts "offlineasm: Nothing changed."
59            exit 0
60        end
61    }
62end
63
64originalAST = parse(inputFlnm)
65
66#
67# Optimize the AST to make configuration extraction faster. This reduces the AST to a form
68# that only contains the things that matter for our purposes: offsets, sizes, and if
69# statements.
70#
71
72class Node
73    def offsetsPruneTo(sequence)
74        children.each {
75            | child |
76            child.offsetsPruneTo(sequence)
77        }
78    end
79    
80    def offsetsPrune
81        result = Sequence.new(codeOrigin, [])
82        offsetsPruneTo(result)
83        result
84    end
85end
86
87class IfThenElse
88    def offsetsPruneTo(sequence)
89        ifThenElse = IfThenElse.new(codeOrigin, predicate, thenCase.offsetsPrune)
90        ifThenElse.elseCase = elseCase.offsetsPrune
91        sequence.list << ifThenElse
92    end
93end
94
95class StructOffset
96    def offsetsPruneTo(sequence)
97        sequence.list << self
98    end
99end
100
101class Sizeof
102    def offsetsPruneTo(sequence)
103        sequence.list << self
104    end
105end
106
107prunedAST = originalAST.offsetsPrune
108
109File.open(outputFlnm, "w") {
110    | outp |
111    $output = outp
112    outp.puts inputHash
113    length = 0
114    emitCodeInAllConfigurations(prunedAST) {
115        | settings, ast, backend, index |
116        offsetsList = ast.filter(StructOffset).uniq.sort
117        sizesList = ast.filter(Sizeof).uniq.sort
118        length += OFFSET_HEADER_MAGIC_NUMBERS.size + (OFFSET_MAGIC_NUMBERS.size + 1) * (1 + offsetsList.size + sizesList.size)
119    }
120    outp.puts "static const unsigned extractorTable[#{length}] = {"
121    emitCodeInAllConfigurations(prunedAST) {
122        | settings, ast, backend, index |
123        OFFSET_HEADER_MAGIC_NUMBERS.each {
124            | number |
125            $output.puts "unsigned(#{number}),"
126        }
127
128        offsetsList = ast.filter(StructOffset).uniq.sort
129        sizesList = ast.filter(Sizeof).uniq.sort
130        
131        emitMagicNumber
132        outp.puts "#{index},"
133        offsetsList.each {
134            | offset |
135            emitMagicNumber
136            outp.puts "OFFLINE_ASM_OFFSETOF(#{offset.struct}, #{offset.field}),"
137        }
138        sizesList.each {
139            | offset |
140            emitMagicNumber
141            outp.puts "sizeof(#{offset.struct}),"
142        }
143    }
144    outp.puts "};"
145}
146
147$stderr.puts "offlineasm: offset extractor #{outputFlnm} successfully generated."
148
149