JIT Compiler and its Types

Question

I came across few forums where i found people saying there are three types of JIT Compiler and they are

1. Pre JIT
2. ECO JIT and
3. Normal JIT

Is this true/right?

I searched in MSDN, i did not get anything about this classification. Can someone through some light on this?

Ram

Answer 1

Sure, there are lots of different IL-to-native compilers.

The NGEN "native generator" compiler is usually referred to as the "prejit" compiler even though that makes no sense at all. A jit compiler is called that because it runs Just In Time. Running "previous" to "just in time" obviously is the opposite of "just in time"! But that's what people call it, even though the name is self-contradictory.

Every version of the CLR for every platform has its own jitter, and I would imagine that jitters for memory-constrained devices are more economical with that resource than the desktop or silverlight jitters. I've never heard them referred to as "eco jit" internally, but this is not my area of expertise.