On Fri, Jan 08, 2016 at 09:39:11AM -0600, James Norris wrote:
> On 01/08/2016 09:30 AM, Jakub Jelinek wrote:
> >On Fri, Jan 08, 2016 at 09:24:14AM -0600, James Norris wrote:
> >>This patch removes the constraint whereby the PTX
> >>emitted was only for sm_30 GPU's. With this removal,
> >>the PTX emitted will be targeted for the current
> >>context, i.e., attached GPU.
> >>
> >>Bootstrapped/regtested on x86_64-linux, ok for trunk?
> >How does that work?
> >I see
> >static void
> >nvptx_file_start (void)
> >{
> > fputs ("// BEGIN PREAMBLE\n", asm_out_file);
> > fputs ("\t.version\t3.1\n", asm_out_file);
> > fputs ("\t.target\tsm_30\n", asm_out_file);
> > fprintf (asm_out_file, "\t.address_size %d\n", GET_MODE_BITSIZE (Pmode));
> > fputs ("// END PREAMBLE\n", asm_out_file);
> >}
> >which I'd guess means the PTX code can be executed in sm_30 and newer only
> >anyway.
> >
> > Jakub
>
> Yes. Per the PTX ISA manual for the .target directive: "In general,
> generations of SM architectures follow an onion layer model, where
> each generation adds new features and retains all features of
> previous generations."
And CU_JIT_TARGET / CU_TARGET_COMPUTE_30 requests JITting only on sm_30 and
nothing else, or just on sm_30 or later, something else?
This really should be reviewed by somebody familiar with CUDA more than
myself.
Jakub
