Questions tagged [jit]
The JIT (just-in-time compilation) is a method to improve the run-time performance of computer programs based on byte code (virtual machine code).
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Are shorter variants of machine instructions worth it?
I'm writing a JIT runtime, and I've started thinking about shorter variants of some instructions.
In x64 we can do at least two kinds of jumps: rel8 and rel32. The first one takes say 2 bytes (opcode +...
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How modern runtimes handle both interpreted and JITted code at the same time?
I have a personal project, I want to write a JIT compiler/runtime in Rust (well, the language is not that relevant). I'm thinking about using a technique where the code is interpreted first and then ...
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How does a JIT compiler actually emit and then call the emitted native code?
Assuming that a VM runs a JIT compiler on otherwise "interpreted" code, such as a line by line interpreter or some form of bytecode/IL code and determines that it can create optimised native ...
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Why do we oppose AOT and JIT compilation. Can they be complementary?
I'm just not sure as to why JIT (Just-in-time) and AOT (Ahead-of-time) are often presented in contradiction to another.
If we do not care about about portability, it feels to me that a program could ...
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What EXACTLY can the Java JIT do?
Is there any documentation that exhaustively lists the optimizations that the Java JIT can make? I can easily find articles with examples of what the JIT can do, but I want to make sure that it's not ...
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Do JITs typically have their own internal assembler, use a library, or use an executable assembler?
Amongst the successful and widely used JITs out there (e.g. JVM JITs, JavaScript JITs, LuaJIT), is there a strong consensus on how the JIT compiler should interface with an assembler? The plausible ...
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How to manage dynamically generated variables in Assembly
Along the lines of How v8 JIT compiler manages dynamically changing variables, wondering how you would go about creating dynamically generated variables in assembly. Not necessarily looking for ...
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Why hasn't Python been optimized like modern Javascript implementations?
Modern Javascript implementations like V8 (Chrome), SpiderMonkey (Firefox), and Chakra (IE/Edge) all have JIT compilation, and a number of other optimizations to improve performance.
Why doesn't ...
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Comparison of modern browsers' javascript engine JITs
I understands that most of the recent browsers use JIT compilation to execute javascript. What I do not understand is: which part of javascript is JIT'ed - the script, or the bytecode?
Let me explain....
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How do JIT interpreters handle variable names?
Let's say I am to design a JIT interpreter that translates IL or bytecode to executable instructions at runtime. Every time a variable name is encountered in the code, the JIT interpreter has to ...
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JIT based on precompiled code templates
This is a crazy idea that I just came up with, and I'm interested in knowing if it would be workable, or if someone already wrote about or implemented it.
Imagine you are on a platform (a game ...
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Can JIT compilation be non-deterministic?
I have been profiling a lot of javascript today in writing a firefox js engine bug report, and started really noticing the slight differences between JIT compilations.
While there are some obvious ...
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How does Chrome V8 work? And why was JavaScript not JIT-Compiled in the first place?
I have been researching Interpreters/Compilers, then I stumbled across JIT-Compilation - specifically Google Chrome's V8 Javascript Engine.
My questions are -
How can it be faster than standard ...
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What should JITed bytecode do exactly?
I'm working on a VM (and a scripting language for it) that I plan to implement JITing for. I'm only working on the "plumbing" of it now, but I don't want the JIT compiler to be an afterthought. ...
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Do java .class files have a lexer/parser?
I've been learning ANTLR, by writing my own (extremely simple!) programming language
It made me curious about how the lexer/parser/AST is implemented for java. Obviously there is a grammar for .java ...
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