Hopefully this snapshot will be a little better quality, but don't hold your breath, because the main change in this version is the addition of local variable liveness analysis to the verifier. This required some tricky code and made it clear to me (again) that the verifier desperately needs to be rewritten.
The trigger for the local variable liveness analysis was to be able to emit debugging information for local variables, but it also has the nice side effect of allowing a little better code generation. Previously, if a local variable slot was shared between two different reference types, the .NET local would have the type of the common base type, even if the uses were in fact totally distinct. The compiler had to emit downcasts whenever it emitted a load from one of those locals. In classpath.dll there were 1288 such downcasts. With the new liveness information, it is now possible to split those Java locals in multiple .NET locals, so these downcasts are now gone. Another optimization, which doesn't seem all that exciting, is the elimination of dead stores to local variables. In itself this is a fairly pointless optimization, because the CLR/Mono JIT will probably do it anyway. However, there is one very important optimization that can be done because of dead store elimination, in exception handling. Whenever an exception handler discards the exception object and the IKVM bytecode compiler can detect this, it can skip the (expensive) stack trace capturing that is normally required. I had already hacked some support to recognize these exception handlers (in classpath.dll there were 313 optimized exception handlers), but now it works much better (there are now 444 optimized exception handlers).
New snapshots: just the binaries and source plus binaries.
I apologize for the lameness of this, but the comment spam was driving me nuts.
In order to be able to post a comment, you need to answer a simple question. Hopefully this question
is easy enough not to annoy serious commenters, but hard enough to keep the spammers away.
Anti-Spam Question: What method on java.lang.System returns an object's original hashcode (i.e. the
one that would be returned by java.lang.Object.hashCode() if it wasn't overridden)? (case is significant)
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