[LLVMdev] appropriate for run-time compilation of DSL?

[Reid Kleckner]

On Mon, Apr 11, 2011 at 11:37 PM, edA-qa mort-ora-y <eda-qa at disemia.com> wrote:
>> There isn't great support for this in the LLVM JIT, but IIRC some
>> clients have managed this by subclassing the JITMemoryManager to copy
>> the code when the function has finished being emitted.  I don't know
>> if it's possible to ensure that the code will be position independent.
>
> I'll start my investigation here then, as this is actually quite
> critical to us -- we can't afford the final JIT/compilation overhead on
> our target machines. Note that I do presume that LLVM is extremely fast,
> but our requirements sit at the microsecond level, and we will have
> thousands of these things to compile in a day.

Then LLVM might not be the right tool for the job.  It's not a very
fast JIT compiler, although this is an area we'd like to improve.  To
whether it's fast enough, you could modify the Kaleidoscope example to
time compiling several functions.

Reid