JavaScriptCore-1097.3.tar.gz

[apple/javascriptcore.git] / offlineasm / generate_offset_extractor.rb

diff --git a/offlineasm/generate_offset_extractor.rb b/offlineasm/generate_offset_extractor.rb
new file mode 100644 (file)
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+++ b/offlineasm/generate_offset_extractor.rb
@@ -0,0 +1,145 @@
+#!/usr/bin/env ruby
+
+# Copyright (C) 2011 Apple Inc. All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions
+# are met:
+# 1. Redistributions of source code must retain the above copyright
+#    notice, this list of conditions and the following disclaimer.
+# 2. Redistributions in binary form must reproduce the above copyright
+#    notice, this list of conditions and the following disclaimer in the
+#    documentation and/or other materials provided with the distribution.
+#
+# THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS''
+# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
+# THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+# PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS
+# BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+# CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+# SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+# INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+# CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+# ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
+# THE POSSIBILITY OF SUCH DAMAGE.
+
+$: << File.dirname(__FILE__)
+
+require "backends"
+require "digest/sha1"
+require "offsets"
+require "parser"
+require "self_hash"
+require "settings"
+require "transform"
+
+inputFlnm = ARGV.shift
+outputFlnm = ARGV.shift
+
+$stderr.puts "offlineasm: Parsing #{inputFlnm} and creating offset extractor #{outputFlnm}."
+
+def emitMagicNumber
+    OFFSET_MAGIC_NUMBERS.each {
+        | number |
+        $output.puts "#{number},"
+    }
+end
+
+inputHash = "// offlineasm input hash: #{parseHash(inputFlnm)} #{selfHash}"
+
+if FileTest.exist? outputFlnm
+    File.open(outputFlnm, "r") {
+        | inp |
+        firstLine = inp.gets
+        if firstLine and firstLine.chomp == inputHash
+            $stderr.puts "offlineasm: Nothing changed."
+            exit 0
+        end
+    }
+end
+
+originalAST = parse(inputFlnm)
+
+#
+# Optimize the AST to make configuration extraction faster. This reduces the AST to a form
+# that only contains the things that matter for our purposes: offsets, sizes, and if
+# statements.
+#
+
+class Node
+    def offsetsPruneTo(sequence)
+        children.each {
+            | child |
+            child.offsetsPruneTo(sequence)
+        }
+    end
+    
+    def offsetsPrune
+        result = Sequence.new(codeOrigin, [])
+        offsetsPruneTo(result)
+        result
+    end
+end
+
+class IfThenElse
+    def offsetsPruneTo(sequence)
+        ifThenElse = IfThenElse.new(codeOrigin, predicate, thenCase.offsetsPrune)
+        ifThenElse.elseCase = elseCase.offsetsPrune
+        sequence.list << ifThenElse
+    end
+end
+
+class StructOffset
+    def offsetsPruneTo(sequence)
+        sequence.list << self
+    end
+end
+
+class Sizeof
+    def offsetsPruneTo(sequence)
+        sequence.list << self
+    end
+end
+
+prunedAST = originalAST.offsetsPrune
+
+File.open(outputFlnm, "w") {
+    | outp |
+    $output = outp
+    outp.puts inputHash
+    length = 0
+    emitCodeInAllConfigurations(prunedAST) {
+        | settings, ast, backend, index |
+        offsetsList = ast.filter(StructOffset).uniq.sort
+        sizesList = ast.filter(Sizeof).uniq.sort
+        length += OFFSET_HEADER_MAGIC_NUMBERS.size + (OFFSET_MAGIC_NUMBERS.size + 1) * (1 + offsetsList.size + sizesList.size)
+    }
+    outp.puts "static const unsigned extractorTable[#{length}] = {"
+    emitCodeInAllConfigurations(prunedAST) {
+        | settings, ast, backend, index |
+        OFFSET_HEADER_MAGIC_NUMBERS.each {
+            | number |
+            $output.puts "#{number},"
+        }
+
+        offsetsList = ast.filter(StructOffset).uniq.sort
+        sizesList = ast.filter(Sizeof).uniq.sort
+        
+        emitMagicNumber
+        outp.puts "#{index},"
+        offsetsList.each {
+            | offset |
+            emitMagicNumber
+            outp.puts "OFFLINE_ASM_OFFSETOF(#{offset.struct}, #{offset.field}),"
+        }
+        sizesList.each {
+            | offset |
+            emitMagicNumber
+            outp.puts "sizeof(#{offset.struct}),"
+        }
+    }
+    outp.puts "};"
+}
+
+$stderr.puts "offlineasm: offset extractor #{outputFlnm} successfully generated."
+