[LLVMdev] Scheme + LLVM JIT

[Chris Lattner]

On Mon, 16 May 2005, Alexander Friedman wrote:
> On May 16, Chris Lattner wrote:
>> I'm concerned that this leaks the buffer created for the file, can you
>> verify that it doesn't?
>
> I can verify that the functionality doesn't change. If the buffer was
> leaked before, it'll be leaked now.
>
> However, in 'Lexer.l', you have the following code:
>
>
> <<EOF>>         {
>                  /* Make sure to free the internal buffers for flex when we are
>                   * done reading our input!
>                   */
>                  yy_delete_buffer(YY_CURRENT_BUFFER);
>                  return EOF;
>                }
>
> Which should take care of it.

Ok, that makes sense.

> I made a 'FibInC' example that uses my little c-wrapper (which in turn
> uses this). I can submit  all of those when they are cleaned up (and
> linking correctly - more on that later).

cool, ok.

>> One suggestion, you might change the API to be something like this:
>>
>> ParseAsmString(const char *, Module *)
>>
>> Where the function parses the string and appends it into the specified
>> module.  This would make self-extending code simpler (no need to parse
>> into one module then link into the preexisting one).
>
> This seems reasonable, but what happens to the users of the module if
> it were to be updated - for example, if I load said module in the jit,
> and then add something to it.

This should be fine.  The JIT won't touch a function until it is called.

> About the linking. Is it possible (within the current makefile
> framework) to create a shared library that (statically) contains some
> set of llvm libraries (including the JIT, which currenlty only works
> if building a tool).

I don't know.  It seems possible: each library can be built as a .so file 
individually.  Each directory can also be relinked into a single .o file. 
It seems logical that you could take these .o files and make a .so file :)

> I wish to be able to do the following, assuming that I named that
> library LLVM_C
>
> gcc -lc -lLLVM_C c_file_using_llvm.c -I<stuff> -L<stuff>
>
> I *could* build everything as a shared library, and include everything
> on the command line that way, but that seems a bit errorprone, not to
> mention the fact that building everything with PIC takes ~3x longer.

This should be possible, though our current makefile system is not going 
to do this automatically right now.

-Chris

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