bytecode

问题 So I know that there exists 2 memory areas: Stack and Heap . I also know that if you create a local variable it will live in the Stack, not in the heap. Stack will grow as we push data into it as in: Now I will try to pass the confusion I am having to you: For example this simple Java Code: public class TestClass { public static void main(String[] args) { Object foo = null; Object bar = null; } } is translated into this byte code: public static void main(java.lang.String[]); Code: Stack=1,

问题 I followed the sample code in the "3.2.6 Inline Method“ in the http://asm.ow2.org/current/asm-transformations.pdf, to inline a MethodNode to a call site. My problem is that there are some unexpected instructions shown in the generated bytecode after inlining (these bytecodes are inconsistent to my code), and the problem only exists when an ifeq is after inlineed method body and the variable on the stack is loaded by xLoad. I still have not found the root cause for the issue. Now i am start to

问题 If I compile an application using Java 5 code into bytecode, are the resulting .class files going to be able to run under Java 1.4? If the latter can work and I'm trying to use a Java 5 framework in my Java 1.4 application, is there anything I should watch out for? 回答1: Nope! .class files are forward compatible only. Java 5 introduced new classfile attributes and format changes, to handle Varargs, enums, and generics. Java 4 would just fail when processing these. However, there is the

问题 I'm confused about machine code and native code in the context of .NET languages. What is the difference between them? Are they the same? 回答1: The terms are indeed a bit confusing, because they are sometimes used inconsistently. Machine code: This is the most well-defined one. It is code that uses the byte-code instructions which your processor (the physical piece of metal that does the actual work) understands and executes directly. All other code must be translated or transformed into

问题 If I create a new item in Jasmin assembly and then store it, I do it with the instruction aload, since it's an address: new Object dup invokespecial..... astore_3 ; load the object reference into local variable 3 Now, if I want to save a string from the constant pool... I would create it with ldc and then save it with aload as well: ldc "Great string" astore_3 ; save the reference to the actual string in the constant pool Now... are these addresses on the same form and the same number of

问题 I have the following problem: From a SQL Server database I am reading data using python module pypyodbc and ODBC Driver 13 for SQL Server and writing to txt files. Database contains all kinds of special characters and they read as: 'PR\xc3\x86KVAL' The '\xc3\x86' part is bytecode and should be interpreted that way. The other characters should be interpreted as shown. UTF8 would translate '\xc3\x86' to Æ. If I type the value in b'PR\xc3\x86KVAL' , python recognizes it as bytecode and I can

问题 Do you guys think this is a good generic framework for atomic operations? Also do you think its correct to say With respect to Java applicatitions individual byte codes are atomic as there is no way of executing more than one byte code at a time with a single JVM? So if there was a single byte code for if else, then this if else instruction would be atomic? // CAS, Compare and Swap public abstract class CASOperation<T> { protected T valueAtStart; public CASOperation(){ valueAtStart =

问题 Do you guys think this is a good generic framework for atomic operations? Also do you think its correct to say With respect to Java applicatitions individual byte codes are atomic as there is no way of executing more than one byte code at a time with a single JVM? So if there was a single byte code for if else, then this if else instruction would be atomic? // CAS, Compare and Swap public abstract class CASOperation<T> { protected T valueAtStart; public CASOperation(){ valueAtStart =

问题 Do you guys think this is a good generic framework for atomic operations? Also do you think its correct to say With respect to Java applicatitions individual byte codes are atomic as there is no way of executing more than one byte code at a time with a single JVM? So if there was a single byte code for if else, then this if else instruction would be atomic? // CAS, Compare and Swap public abstract class CASOperation<T> { protected T valueAtStart; public CASOperation(){ valueAtStart =

问题 We wrote a simple PostScript interpreter in Java and want to optimize it by generating bytecode directly for specific parts of source code. For this we need to load the object from the context of the Java bytecode context. Specify such object in the signature of the generated bytecode method is not good, because they may be in a large amount in our case. In Java Asm we have method public void visitLdcInsn(Object cst) It visits a LDC instruction. Parameter cst - the constant to be loaded on