1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
|
/* NSC -- new Scala compiler
* Copyright 2005-2014 LAMP/EPFL
* @author Martin Odersky
*/
package scala.tools.nsc.backend.jvm
import scala.tools.asm.tree.{InsnList, AbstractInsnNode, ClassNode, MethodNode}
import java.io.{StringWriter, PrintWriter}
import scala.tools.asm.util.{CheckClassAdapter, TraceClassVisitor, TraceMethodVisitor, Textifier}
import scala.tools.asm.{ClassWriter, Attribute, ClassReader}
import scala.collection.convert.decorateAsScala._
import scala.tools.nsc.backend.jvm.analysis.InitialProducer
import scala.tools.nsc.backend.jvm.opt.InlineInfoAttributePrototype
object AsmUtils {
/**
* Print the bytecode of methods generated by GenBCode to the standard output. Only methods
* whose name contains `traceMethodPattern` are traced.
*/
final val traceMethodEnabled = false
final val traceMethodPattern = ""
/**
* Print the bytecode of classes generated by GenBCode to the standard output.
*/
final val traceClassEnabled = false
final val traceClassPattern = ""
/**
* Print the bytedcode of classes as they are serialized by the ASM library. The serialization
* performed by `asm.ClassWriter` can change the code generated by GenBCode. For example, it
* introduces stack map frames, it computes the maximal stack sizes, and it replaces dead
* code by NOPs (see also https://github.com/scala/scala/pull/3726#issuecomment-42861780).
*/
final val traceSerializedClassEnabled = false
final val traceSerializedClassPattern = ""
def traceMethod(mnode: MethodNode): Unit = {
println(s"Bytecode for method ${mnode.name}")
println(textify(mnode))
}
def traceClass(cnode: ClassNode): Unit = {
println(s"Bytecode for class ${cnode.name}")
println(textify(cnode))
}
def traceClass(bytes: Array[Byte]): Unit = traceClass(readClass(bytes))
def readClass(bytes: Array[Byte]): ClassNode = {
val node = new ClassNode()
new ClassReader(bytes).accept(node, Array[Attribute](InlineInfoAttributePrototype), 0)
node
}
/**
* Returns a human-readable representation of the cnode ClassNode.
*/
def textify(cnode: ClassNode): String = {
val trace = new TraceClassVisitor(new PrintWriter(new StringWriter))
cnode.accept(trace)
val sw = new StringWriter
val pw = new PrintWriter(sw)
trace.p.print(pw)
sw.toString
}
/**
* Returns a human-readable representation of the code in the mnode MethodNode.
*/
def textify(mnode: MethodNode): String = {
val trace = new TraceClassVisitor(new PrintWriter(new StringWriter))
mnode.accept(trace)
val sw = new StringWriter
val pw = new PrintWriter(sw)
trace.p.print(pw)
sw.toString
}
/**
* Returns a human-readable representation of the given instruction.
*/
def textify(insn: AbstractInsnNode): String = insn match {
case _: InitialProducer =>
insn.toString
case _ =>
val trace = new TraceMethodVisitor(new Textifier)
insn.accept(trace)
val sw = new StringWriter
val pw = new PrintWriter(sw)
trace.p.print(pw)
sw.toString.trim
}
/**
* Returns a human-readable representation of the given instruction sequence.
*/
def textify(insns: Iterator[AbstractInsnNode]): String = {
val trace = new TraceMethodVisitor(new Textifier)
insns.foreach(_.accept(trace))
val sw: StringWriter = new StringWriter
val pw: PrintWriter = new PrintWriter(sw)
trace.p.print(pw)
sw.toString.trim
}
/**
* Returns a human-readable representation of the given instruction sequence.
*/
def textify(insns: InsnList): String = textify(insns.iterator().asScala)
/**
* Run ASM's CheckClassAdapter over a class. Returns None if no problem is found, otherwise
* Some(msg) with the verifier's error message.
*/
def checkClass(classNode: ClassNode): Option[String] = {
val cw = new ClassWriter(ClassWriter.COMPUTE_MAXS)
classNode.accept(cw)
val sw = new StringWriter()
val pw = new PrintWriter(sw)
CheckClassAdapter.verify(new ClassReader(cw.toByteArray), false, pw)
val res = sw.toString
if (res.isEmpty) None else Some(res)
}
}
|
