Re: [Matlisp-devel] BLAS (was Matlisp tests)

[Raymond T. <toy...@gm...>]

On 3/11/12 11:11 AM, Akshay Srinivasan wrote:
> On 03/11/2012 12:37 PM, Raymond Toy wrote:
>> On 3/10/12 7:03 PM, Akshay Srinivasan wrote:
>>> On 03/10/2012 11:16 PM, Raymond Toy wrote:
>>>> On 3/10/12 8:40 AM, Akshay Srinivasan wrote:
>>>>
>>>>>> It would be nice to be able to detect either mode and have 
>>>>>> the ffi do the right thing, but I think many lisps do not 
>>>>>> support structure returns the way gcc is doing it now.
>>>>> It returns a struct ? I never could get hold of the 
>>>>> documentation for that.
>>>> That's my understanding.  And when I look at the disassembly 
>>>> for a simple Fortran function, it returns the real and 
>>>> imaginary parts in xmm0 and xmm1 (at least on OSX).
>>> Hmm. Too clumsy and non-portable to support all that, no ?
>> It would be good if cffi supported that, but I suspect not.
>>>>>> We also have an alternative: Add simple C wrappers that
>>>>>> use the f2c-mode return and call the Fortran routine
>>>>>> directly.
>>>>> CBLAS :) (not the netlib version).
> After some more thinking, I vote for adding wrapper subroutine around
> zdotu/zdotc in F77. It'll be far too much boring work to migrate to
> CBLAS, given that I seem to be able to handle ordering quite well
> within lisp itself. There aren't any other complex returning functions
> in BLAS, are there ?
Let me do a grep....Nope.  Looks like those are the only two.

Not quite sure what you're going to do here.  You want to write two C
wrapper functions that call zdotu/zdotc correctly, and have the wrapper
use the f2c convention?

Since we already detect if we need -ff2c, what is the utility for this
when matlisp builds its own libraries?  Of course, for atlas, I can see
that we would want this if we've determined that atlas is not
compatible.  That would be a nice enhancement.
>
> We probably don't need any other f2c features, since most functions I
> know only take character arguments instead of string ones.
Fortunately, matlisp is in control of that because I think it is valid
fortran to pass in, say, 'Transpose', instead of 'T'.

Ray