Re: [PING] nvptx: '-mframe-malloc-threshold', '-Wframe-malloc-threshold' (was: Handling of large stack objects in GPU code generation -- maybe transform into heap allocation?)

[Jerry D via Fortran]

On 1/11/23 4:06 AM, Thomas Schwinge wrote:
Hi!
Ping -- the '-mframe-malloc-threshold' idea, at least.

Note that while this issue originally did pop up for Fortran I/O, it's
likewise relevant for other functions that maintain big frames, for
example in newlib:

     libc/string/libc_a-memmem.o:.local .align 16 .b8 %frame_ar[2064];
     libc/string/libc_a-strcasestr.o:.local .align 16 .b8 %frame_ar[2064];
     libc/string/libc_a-strstr.o:.local .align 16 .b8 %frame_ar[2064];
     libm/math/libm_a-k_rem_pio2.o:.local .align 16 .b8 %frame_ar[560];

Therefore a generic solution (or, workaround if you'd like) does seem
appropriate.

---snip ---

AS a gfortranner I have to at least say anyone doing fortran I/O on a 
GPU is nuts.

With that said, a configurable option to address the broader issue makes 
sense. Perhaps the default threshold should be whatever it is now and if 
someone has a real situation where it is needed, they can adjust.

Regards,

Jerry