Re: octave and LLVM google summer of code project

[John W. Eaton]

On 19-Apr-2008, Eugene I wrote:

| The basic approach is to try to compile the AST, if it fails (feature not
| implemented or type change) then fall back to interpreting the code.

Does that happen for each statement, or is it required that a full
function be compiled?  Does it work for each invocation of a function
(i.e., you know the types of the arguments for a given call), or are
you doing some type inferencing?  If so, how where is the code that
does that part?

| For
| vector and matrix operations, we simply call BLAS code (through same
| interface that the interpreter uses) under the assumptions that compiled
| code won't provide any speed up. The main advantage of JIT compiled code is
| for array index operations - you can get fantastic results.

Can you give an example of the type of operation where you see an
improvement?  What is the difference in the way the two operations
are handled by the FreeMat interpreter and LLVM?

jwe