llvm dev - Oct 2008 - [LLVMdev] Dynamic Optimization Infrastructure

Does anyone know if LLVM will soon have a dynamic optimization
infrastructure, namely support to generate trampolines back to the
JIT/execution manager that get run when a piece of code's frequency exceeds
a threshold? I see that there already is a relinkAndRecompileFunction in the
JIT, which will be useful. Rather than roll my own mechanisms and have to
worry about jumping back to code that gets replaced, are there already works
in progress?

Also, is there a way to generate platform independent trampolines (e.g.
generate IR that calls a function pointer to the execution engine I want to
go to). LLVM seems to be pretty strict about type casts, so I was afraid I
wouldn't be able to generate a function pointer initialized to arbitrary
data.
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On Oct 3, 2008, at 3:14 PM, Yale Zhang wrote:
> Does anyone know if LLVM will soon have a dynamic optimization  
> infrastructure, namely support to generate trampolines back to the  
> JIT/execution manager that get run when a piece of code's frequency  
> exceeds a threshold? I see that there already is a  
> relinkAndRecompileFunction in the JIT, which will be useful. Rather  
> than roll my own mechanisms and have to worry about jumping back to  
> code that gets replaced, are there already works in progress?
Not that I am aware of. Although there appears to be considerable  
interests in this. Patches welcome.
>
>
> Also, is there a way to generate platform independent trampolines  
> (e.g. generate IR that calls a function pointer to the execution  
> engine I want to go to). LLVM seems to be pretty strict about type  
> casts, so I was afraid I wouldn't be able to generate a function  
> pointer initialized to arbitrary data.
Not sure if this is what you are looking for:
http://llvm.org/docs/LangRef.html#int_trampoline

Evan
>
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