There are a lot of similarities between both implementations (and in my opinion: yes, they’re both “virtual machines”). For one thing, they’re both stack-based VM’s, with no notion of “registers” like we’re used to seeing in a modern CPU like the x86 or PowerPC. The evaluation of all expressions ((1 + 1) / 2) is … Read more
There are a lot of misconceptions here. I suppose you could think of .Net as a virtual machine if you really wanted, but let’s look at how the .Net Framework really handles your code. The typical scenario looks like this You write a .Net program in C#, VB.Net, F#, or some other compatible language. That … Read more
wow, this turned out to be a lot more painful than I expected. 100% of the pain was linux protecting the program from being overwritten and/or executing data. Two solutions shown below. And a lot of googling was involved so the somewhat simple put some instruction bytes and execute them was mine, the mprotect and … Read more
In general, Just-in-time compilation refers to compiling native code at runtime and executing it instead of (or in addition to) interpreting. Some VMs, such as Google V8, don’t even have an interpreter; they JIT compile every function that gets executed (with varying degrees of optimization). On Stack Replacement (OSR) is a technique for switching between … Read more
Constant pool is a part of .class file (and its in-memory representation) that contains constants needed to run the code of that class. These constants include literals specified by the programmer and symbolic references generated by compiler. Symbolic references are basically names of classes, methods and fields referenced from the code. These references are used … Read more