Compiling the JIT with LLVM 3.8

[Julien Bect]

Hi all,

I have managed to compile Octave stable (4.2.1+) with LLVM 3.8 using MCJIT.

I have a very limited understanding of both LLVM and Octave's JIT, but 
there some encouraging signs:

1) I can build with --enable-jit

2) I get a good speedup on the attached function

address@hidden:~/.local/src/octave-stable$ ./run-octave --no-gui
GNU Octave, version 4.2.1
[...]

octave:1> tic;  z = test_pisum (),  toc
z =  1.6448
Elapsed time is 11.6463 seconds.

octave:2> jit_enable (1)

octave:3> tic;  z = test_pisum (),  toc
z =  1.6448
Elapsed time is 0.054471 seconds.

octave:4> tic;  z = test_pisum (),  toc
z =  1.6448
Elapsed time is 0.019253 seconds.

octave:5> tic;  z = test_pisum (),  toc
z =  1.6448
Elapsed time is 0.019371 seconds

Bad news: I still get a crash on make check due to jit.tst

My patches are still very unpolished (supports only LLVM 3.8, not 
autoconf stuff yet) but I can share them if someone is interested.

Where would be the proper place ?  bug tracker ?  patch tracker ? 
somewhere else ?

@++
Julien

test_pisum.m
Description: Text Data