[Mesa-dev] [PATCH 4/5] i965/vec4_nir: Do boolean source modifier resolves on BDW+

[Jason Ekstrand]

On Mon, Aug 10, 2015 at 11:16 AM, Matt Turner <mattst88 at gmail.com> wrote:
> On Mon, Aug 3, 2015 at 5:22 PM, Jason Ekstrand <jason at jlekstrand.net> wrote:
>> On BDW+, the negation source modifier on NOT, AND, OR, and XOR, is actually
>> a boolean negate and not an integer negate.  However, NIR's soruce
>> modifiers are the integer version.  We have to resolve it with a MOV prior
>> to emitting the actual instruction.  This is basically the same thing we do
>> in the FS backend.
>> ---
>>  src/mesa/drivers/dri/i965/brw_vec4.h           |  1 +
>>  src/mesa/drivers/dri/i965/brw_vec4_nir.cpp     | 15 +++++++++++++++
>>  src/mesa/drivers/dri/i965/brw_vec4_visitor.cpp | 13 +++++++++++++
>>  3 files changed, 29 insertions(+)
>>
>> diff --git a/src/mesa/drivers/dri/i965/brw_vec4.h b/src/mesa/drivers/dri/i965/brw_vec4.h
>> index 985886d..ff143be 100644
>> --- a/src/mesa/drivers/dri/i965/brw_vec4.h
>> +++ b/src/mesa/drivers/dri/i965/brw_vec4.h
>> @@ -320,6 +320,7 @@ public:
>>                     dst_reg dst, src_reg src0, src_reg src1);
>>
>>     src_reg fix_3src_operand(src_reg src);
>> +   src_reg resolve_source_modifiers(src_reg src);
>>
>>     vec4_instruction *emit_math(enum opcode opcode, const dst_reg &dst, const src_reg &src0,
>>                                 const src_reg &src1 = src_reg());
>> diff --git a/src/mesa/drivers/dri/i965/brw_vec4_nir.cpp b/src/mesa/drivers/dri/i965/brw_vec4_nir.cpp
>> index 27f23d0..1b7fb5e 100644
>> --- a/src/mesa/drivers/dri/i965/brw_vec4_nir.cpp
>> +++ b/src/mesa/drivers/dri/i965/brw_vec4_nir.cpp
>> @@ -1020,18 +1020,33 @@ vec4_visitor::nir_emit_alu(nir_alu_instr *instr)
>>     }
>>
>>     case nir_op_inot:
>> +      if (devinfo->gen >= 8) {
>> +         op[0] = resolve_source_modifiers(op[0]);
>> +      }
>>        emit(NOT(dst, op[0]));
>>        break;
>>
>>     case nir_op_ixor:
>> +      if (devinfo->gen >= 8) {
>> +         op[0] = resolve_source_modifiers(op[0]);
>> +         op[1] = resolve_source_modifiers(op[1]);
>> +      }
>>        emit(XOR(dst, op[0], op[1]));
>>        break;
>>
>>     case nir_op_ior:
>> +      if (devinfo->gen >= 8) {
>> +         op[0] = resolve_source_modifiers(op[0]);
>> +         op[1] = resolve_source_modifiers(op[1]);
>> +      }
>>        emit(OR(dst, op[0], op[1]));
>>        break;
>>
>>     case nir_op_iand:
>> +      if (devinfo->gen >= 8) {
>> +         op[0] = resolve_source_modifiers(op[0]);
>> +         op[1] = resolve_source_modifiers(op[1]);
>> +      }
>>        emit(AND(dst, op[0], op[1]));
>>        break;
>>
>> diff --git a/src/mesa/drivers/dri/i965/brw_vec4_visitor.cpp b/src/mesa/drivers/dri/i965/brw_vec4_visitor.cpp
>> index c5c0d2c..639f829 100644
>> --- a/src/mesa/drivers/dri/i965/brw_vec4_visitor.cpp
>> +++ b/src/mesa/drivers/dri/i965/brw_vec4_visitor.cpp
>> @@ -313,6 +313,19 @@ vec4_visitor::fix_3src_operand(src_reg src)
>>  }
>>
>>  src_reg
>> +vec4_visitor::resolve_source_modifiers(src_reg src)
>> +{
>> +   if (!src.abs && !src.negate)
>> +      return src;
>> +
>> +   dst_reg resolved = dst_reg(this, glsl_type::ivec4_type);
>> +   resolved.type = src.type;
>> +   emit(MOV(resolved, src));
>> +
>> +   return src_reg(resolved);
>> +}
>
> The FS passes a pointer to an fs_reg and then updates that. Let's do
> that here to be consistent.

Oh... I was just trying to be consistent with other functions in
vec4_visitor such as fix_3src_operand() above.
--Jason