[Mesa-dev] [Mesa-stable] [PATCH] st/glsl_to_tgsi: use correct writemask when converting generic intrinsics

[Andres Gomez]

Nicolai, this depends on:
https://cgit.freedesktop.org/mesa/mesa/commit/src/mesa?id=944455217b67cb524efef9e628baf09416db5524

Which didn't make it for -stable. Should we cherry-pick that too?


On Mon, 2017-06-12 at 21:45 +0200, Nicolai Hähnle wrote:
> From: Nicolai Hähnle <nicolai.haehnle at amd.com>
> 
> This fixes a bug when lowering ballotARB: previously, using writemask 0xf,
> emit_asm would create TGSI_OPCODE_BALLOT instructions that span two registers
> to cover 4 64-bit channels. This could trample over other a neighbouring
> temporary.
> 
> Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=101360
> Cc: 17.1 <mesa-stable at lists.freedesktop.org>
> ---
>  src/mesa/state_tracker/st_glsl_to_tgsi.cpp | 2 ++
>  1 file changed, 2 insertions(+)
> 
> diff --git a/src/mesa/state_tracker/st_glsl_to_tgsi.cpp b/src/mesa/state_tracker/st_glsl_to_tgsi.cpp
> index c5d2e0f..cb86392 100644
> --- a/src/mesa/state_tracker/st_glsl_to_tgsi.cpp
> +++ b/src/mesa/state_tracker/st_glsl_to_tgsi.cpp
> @@ -3906,20 +3906,22 @@ glsl_to_tgsi_visitor::visit_image_intrinsic(ir_call *ir)
>     if (imgvar->data.memory_volatile)
>        inst->buffer_access |= TGSI_MEMORY_VOLATILE;
>  }
>  
>  void
>  glsl_to_tgsi_visitor::visit_generic_intrinsic(ir_call *ir, unsigned op)
>  {
>     ir->return_deref->accept(this);
>     st_dst_reg dst = st_dst_reg(this->result);
>  
> +   dst.writemask = u_bit_consecutive(0, ir->return_deref->var->type->vector_elements);
> +
>     st_src_reg src[4] = { undef_src, undef_src, undef_src, undef_src };
>     unsigned num_src = 0;
>     foreach_in_list(ir_rvalue, param, &ir->actual_parameters) {
>        assert(num_src < ARRAY_SIZE(src));
>  
>        this->result.file = PROGRAM_UNDEFINED;
>        param->accept(this);
>        assert(this->result.file != PROGRAM_UNDEFINED);
>  
>        src[num_src] = this->result;
-- 
Br,

Andres