Inlining in Graal

[Juan José Fumero Alfonso]

Hi Luka,
  I do not understand your second approach. In which moment the inlining is
applied if I replace it with a constant?

Is possible to force the inlining? I mean, a way to disable the heuristic
for a while and create the inline.

Thanks
Juanjo


2013/11/15 Lukas Stadler <Lukas.Stadler at jku.at>

> Hi Juan,
>
>
> in your working example, the checkInline call is a private method that
> can statically be bound to a specific target, without the help of
> profiling information. Thus, it can be inlined.
> The non-working example, however, contains an virtual/interface call,
> which means that the compiler needs a hint from somewhere as to which
> method could be the target of this call.
> The inlining heuristics in Graal assume that all important code has been
> running in the interpreter for a while (i.e. thousands of times).
> I guess that you are compiling code that has never been executed in the
> interpreter?
>
>
> One solution would be to warm up the method in the interpreter. However,
> the profiling information accumulates, so that the call site will become
> polymorphic and again stop inlining at some point.
> In your case, the closure that does the computation is known at the time
> of compilation (I guess). You could replace the parameter with a
> constant during your compilation process, which should allow the
> compiler to devirtualize the call.
> Is that a strategy that could work for you?
>
>
> - Lukas
>
> >>> Juan José Fumero Alfonso<jjfumero at gmail.com> 11/14/13 4:55 PM >>>
> Hi,
>   I am working on Inlining with Graal in my backend. Using the Log
> information:
>
> -XX:+BootstrapGraal -G:Log=InliningDecisions -XX:+PrintCompilation
>
> I get this:
>
> [thread:1] scope:
>   [thread:1] scope: Inlining
>     [thread:1] scope: Inlining.Inlining
>       [thread:1] scope: Inlining.Inlining.InliningDecisions
>
> * inlining MapEngineOpenCL.kernelComputation at 11: exact
> com.edinburgh.parallel.map.MapEngineOpenCL.checkInline(int):int: trivial
> (relevance=1.000000, probability=1.000000, bonus=1.000000, nodes=6) *
>
> With this code:
>
>     // Testing
>     public void kernelComputation(int[] input, int[] output) {
>         for (int i = 0; i < input.length; i++) {
> *            output[i] = checkInline(input[i]);*
>         }
>     }
>
>     private int checkInline(int a) {
>         return 10 + a;
>     }
>
> So in this case the inlining is working and also the result in my
> program
> is correct. But what I want to do is the following:
>
>
>     public void kernelComputation(T[] input, T[] output) {
>         for (int i = 0; i < input.length; i++) {
>             *output[i] = mInterface.f(input[i]);*
>         }
>     }
>
>
> And the method f is defined dynamically by the user:
>
>
> Integer[] result = Map.apply(data, new MapInterface<Integer>() {
>             @Override
>
>
> *            public Integer f(Integer data) {                return data
> *
> data;             }*
>
>         }).executeOpenCL();
>
>
> What I want to do is the inlining of the f method which is defined
> dynamically by the user.
>
> [thread:1] scope:
>   [thread:1] scope: Inlining
>     [thread:1] scope: Inlining.InliningDecisions
>    * not inlining MapEngineOpenCL.kernelComputation at 14:
> com.edinburgh.parallel.map.MapInterface.f(Object):Object (0 bytes): no
> type
> profile exists*
>
>
> I do not understand why "no type profile exists". Any idea about this? I
> am
> doing the inlining as Graal shows in the tests
> (com.oracle.graal.compiler.test.inlining).
>
> Thank you very much
> Juanjo
>
>
>
>
>