On Fri, Oct 23, 2015 at 12:38 PM, Francisco Jerez <curroje...@riseup.net> wrote: > Matt Turner <matts...@gmail.com> writes: > >> On Fri, Oct 23, 2015 at 11:23 AM, Francisco Jerez <curroje...@riseup.net> >> wrote: >>> Abdiel Janulgue <abdiel.janul...@linux.intel.com> writes: >>> >>>> This patch generates the gather table entries for ordinary uniforms >>>> if they are present. The uniform constants here will later be packed >>>> together with UBO constants. >>>> >>>> Signed-off-by: Abdiel Janulgue <abdiel.janul...@linux.intel.com> >>>> --- >>>> src/mesa/drivers/dri/i965/brw_fs.cpp | 18 +++++++++++++++++- >>>> 1 file changed, 17 insertions(+), 1 deletion(-) >>>> >>>> diff --git a/src/mesa/drivers/dri/i965/brw_fs.cpp >>>> b/src/mesa/drivers/dri/i965/brw_fs.cpp >>>> index d240371..e39d821 100644 >>>> --- a/src/mesa/drivers/dri/i965/brw_fs.cpp >>>> +++ b/src/mesa/drivers/dri/i965/brw_fs.cpp >>>> @@ -1863,8 +1863,11 @@ fs_visitor::assign_constant_locations() >>>> } >>>> } >>>> >>>> - stage_prog_data->nr_params = num_push_constants; >>>> stage_prog_data->nr_pull_params = num_pull_constants; >>>> + stage_prog_data->nr_params = 0; >>> >>> I doubt it's useful to set this to zero here only to calculate it again >>> below. >>> >>>> + >>>> + unsigned const_reg_access[uniforms]; >>> >>> VLAs are a non-standard extension to C++. Usually I'd recommend to use >>> the C++ standard library instead, but because it's banned from the i965 >>> back-end I guess the best you can get is new[]/delete[]. >> >> So... why not just use the extension to C++? Does some compiler we >> care about not support them? >> >> GCC does: https://gcc.gnu.org/onlinedocs/gcc/Variable-Length.html >> >> Looks like this use would be allowed by clang as well: >> http://clang.llvm.org/compatibility.html#vla > > I believe only GCC has a more or less reasonable implementation, Clang's > implementation doesn't allow much of what GCC's allows, like objects > with user-defined constructors or anything non-POD (seems mainly > intended for compatibility with C99 code). MS VC++ doesn't support it > at all.
Okay, so the usage in this patch seems fine since we don't care about MSVC and Clang's support should be sufficient to handle an array of unsigned. > The C99 VLA feature was BTW made optional again in C11, and the similar > feature proposed for C++14 (runtime-sized arrays) was rejected by the > standards committee. Anyway it doesn't seem like a big loss for C++, > there are already standards-compliant ways to get a type-safe array of > automatic duration and dynamically determined size, which support > non-POD C++ objects as element type and behave as first-class C++ > objects themselves unlike in the various VLA-like language extensions. Interesting. Thanks for the information. _______________________________________________ mesa-dev mailing list mesa-dev@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/mesa-dev
