| Message ID | 0b73f43a-1bc2-116b-9fcf-7eb356f5d9d3@codesourcery.com |
|---|---|
| State | New |
| Headers | show |
| Series | [wwwdocs] gcc-12/changes.html: Document -mptx for nvptx | expand |
Early *PING* - and I fixed a wording issue in my patch. OK? Suggestions? Tobias On 14.05.21 00:06, Tobias Burnus wrote: > Document this new flag, added in > https://gcc.gnu.org/g:2a1586401a21dcd43e0f904bb6eec26c8b2f366b > + https://gcc.gnu.org/onlinedocs/gcc/Nvidia-PTX-Options.html#index-mptx > > Any wording suggestions? > > Tobias > > PS: Some background remarks: > > (PTX ISA 3.1 is supported since NVidia's CUDA 5 while 6.3 is supported > since > CUDA 10.0 - and adds very useful new features; current is PTX ISA 7.3 > (CUDA 11.3),* but on the PTX side, 6.3 adds a lot, >6.3 only few > features, > we still may want to support sometime in the future.) > > (The new flag paves the way for additional -misa= flags > (i.e. newer hardware, relevant for enabling ptx instructions which only > newer GPUs support) and newer GPU-hardware-independent PTX ISA features; > hence, either permitting better code generation or for be used to fix > bugs. > While this will change during GCC 12, currently, the generated code is > effectively the same with either -mptx= value.) > > (Regarding the produced instructions, the installed CUDA will JIT > (and then cache) the GCC-generated nvptx in the binary at startup, > optimizing for the available hardware - i.e. the chosen -mptx and > available -misa do not restrict the hardware ability, just that > PTX instructions which is only available in newer PTX / for newer > hardware may not be generated.) > > (* Cf. > https://docs.nvidia.com/cuda/parallel-thread-execution/index.html#release-notes__ptx-release-history > ) > ----------------- Mentor Graphics (Deutschland) GmbH, Arnulfstrasse 201, 80634 München Registergericht München HRB 106955, Geschäftsführer: Thomas Heurung, Frank Thürauf
On 5/17/21 10:49 AM, Tobias Burnus wrote: > Early *PING* - and I fixed a wording issue in my patch. > > OK? Suggestions? > LGTM, thanks. - Tom > Tobias > > On 14.05.21 00:06, Tobias Burnus wrote: >> Document this new flag, added in >> https://gcc.gnu.org/g:2a1586401a21dcd43e0f904bb6eec26c8b2f366b >> + https://gcc.gnu.org/onlinedocs/gcc/Nvidia-PTX-Options.html#index-mptx >> >> Any wording suggestions? >> >> Tobias >> >> PS: Some background remarks: >> >> (PTX ISA 3.1 is supported since NVidia's CUDA 5 while 6.3 is supported >> since >> CUDA 10.0 - and adds very useful new features; current is PTX ISA 7.3 >> (CUDA 11.3),* but on the PTX side, 6.3 adds a lot, >6.3 only few >> features, >> we still may want to support sometime in the future.) >> >> (The new flag paves the way for additional -misa= flags >> (i.e. newer hardware, relevant for enabling ptx instructions which only >> newer GPUs support) and newer GPU-hardware-independent PTX ISA features; >> hence, either permitting better code generation or for be used to fix >> bugs. >> While this will change during GCC 12, currently, the generated code is >> effectively the same with either -mptx= value.) >> >> (Regarding the produced instructions, the installed CUDA will JIT >> (and then cache) the GCC-generated nvptx in the binary at startup, >> optimizing for the available hardware - i.e. the chosen -mptx and >> available -misa do not restrict the hardware ability, just that >> PTX instructions which is only available in newer PTX / for newer >> hardware may not be generated.) >> >> (* Cf. >> https://docs.nvidia.com/cuda/parallel-thread-execution/index.html#release-notes__ptx-release-history >> >> ) >> > ----------------- > Mentor Graphics (Deutschland) GmbH, Arnulfstrasse 201, 80634 München > Registergericht München HRB 106955, Geschäftsführer: Thomas Heurung, > Frank Thürauf
gcc-12/changes.html: Document -mptx for nvptx * htdocs/gcc-12/changes.html (nvptx): Document new -mptx flag. diff --git a/htdocs/gcc-12/changes.html b/htdocs/gcc-12/changes.html index 23f71411..6541cf4e 100644 --- a/htdocs/gcc-12/changes.html +++ b/htdocs/gcc-12/changes.html @@ -101,8 +101,13 @@ a work-in-progress.</p> <!-- <h3 id="nios2">Nios II</h3> --> -<!-- <h3 id="nvptx">NVPTX</h3> --> - +<h3 id="nvptx">NVPTX</h3> +<ul> + <li>The <code>-mptx</code> flag has been added to specify the PTX ISA version + for the generated code; permitted values are <code>3.1</code> + (default and as used previous GCC versions) and <code>6.3</code>. + </li> +</ul> <!-- <h3 id="hppa">PA-RISC</h3> --> <!-- <h3 id="powerpc">PowerPC / PowerPC64 / RS6000</h3> -->