[Mesa-dev] [PATCH 2/8] program: add a helper for rewriting FP position input to sysval

[Ian Romanick]

On 01/07/2016 05:29 PM, Marek Olšák wrote:
> From: Marek Olšák <marek.olsak at amd.com>
> 
> ---
>  src/mesa/program/programopt.c | 27 +++++++++++++++++++++++++++
>  src/mesa/program/programopt.h |  2 ++
>  2 files changed, 29 insertions(+)
> 
> diff --git a/src/mesa/program/programopt.c b/src/mesa/program/programopt.c
> index af78150..24dde57 100644
> --- a/src/mesa/program/programopt.c
> +++ b/src/mesa/program/programopt.c
> @@ -589,3 +589,30 @@ _mesa_remove_output_reads(struct gl_program *prog, gl_register_file type)
>        }
>     }
>  }
> +
> +void
> +_mesa_program_fragment_position_to_sysval(struct gl_program *prog)
> +{
> +   GLuint i;
> +
> +   if (prog->Target != GL_FRAGMENT_PROGRAM_ARB ||
> +       !(prog->InputsRead & BITFIELD64_BIT(VARYING_SLOT_POS)))
> +      return;
> +
> +   prog->InputsRead &= ~BITFIELD64_BIT(VARYING_SLOT_POS);
> +   prog->SystemValuesRead |= 1 << SYSTEM_VALUE_FRAG_COORD;
> +
> +   for (i = 0; i < prog->NumInstructions; i++) {
> +      struct prog_instruction *inst = prog->Instructions + i;
> +      const GLuint numSrc = _mesa_num_inst_src_regs(inst->Opcode);
> +      GLuint j;

I'd make numSrc and j just be unsigned.  With that, this patch is

Reviewed-by: Ian Romanick <ian.d.romanick at intel.com>

> +
> +      for (j = 0; j < numSrc; j++) {
> +         if (inst->SrcReg[j].File == PROGRAM_INPUT &&
> +             inst->SrcReg[j].Index == VARYING_SLOT_POS) {
> +            inst->SrcReg[j].File = PROGRAM_SYSTEM_VALUE;
> +            inst->SrcReg[j].Index = SYSTEM_VALUE_FRAG_COORD;
> +         }
> +      }
> +   }
> +}
> diff --git a/src/mesa/program/programopt.h b/src/mesa/program/programopt.h
> index 757421e..1520d16 100644
> --- a/src/mesa/program/programopt.h
> +++ b/src/mesa/program/programopt.h
> @@ -51,6 +51,8 @@ _mesa_count_texture_instructions(struct gl_program *prog);
>  extern void
>  _mesa_remove_output_reads(struct gl_program *prog, gl_register_file type);
>  
> +extern void
> +_mesa_program_fragment_position_to_sysval(struct gl_program *prog);
>  
>  #ifdef __cplusplus
>  }
>