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

[Nicolai Hähnle]

On 23.06.2017 01:16, Andres Gomez wrote:
> 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?

Ah right, forgot about that. No, just drop the patch for stable.

Thanks,
Nicolai

> 
> 
> 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;