[Mesa-dev] [PATCH 11/11] i965: Use nir_lower_tex for texture coordinate lowering

Iago Toral itoral at igalia.com
Mon Nov 16 06:27:11 PST 2015


On Mon, 2015-11-16 at 11:33 +0100, Iago Toral wrote:
> On Wed, 2015-11-11 at 17:26 -0800, Jason Ekstrand wrote:
> > Previously, we had a rescale_texcoords helper in the FS backend for
> > handling rescaling of texture coordinates.  Now that we can do variants in
> > NIR, we can use nir_lower_tex to do the rescaling for us.  This allows us
> > to delete the i965-specific code and gives us proper TEXTURE_RECTANGLE and
> > GL_CLAMP handling in vertex and geometry shaders.
> > ---
> >  src/mesa/drivers/dri/i965/brw_fs.cpp              |   2 +
> >  src/mesa/drivers/dri/i965/brw_fs.h                |   3 -
> >  src/mesa/drivers/dri/i965/brw_fs_nir.cpp          |   4 +-
> >  src/mesa/drivers/dri/i965/brw_fs_visitor.cpp      | 125 ----------------------
> >  src/mesa/drivers/dri/i965/brw_nir.c               |  23 ++++
> >  src/mesa/drivers/dri/i965/brw_nir.h               |   6 ++
> >  src/mesa/drivers/dri/i965/brw_vec4.cpp            |   2 +
> >  src/mesa/drivers/dri/i965/brw_vec4_gs_visitor.cpp |   2 +
> >  8 files changed, 36 insertions(+), 131 deletions(-)
> > 
> > diff --git a/src/mesa/drivers/dri/i965/brw_fs.cpp b/src/mesa/drivers/dri/i965/brw_fs.cpp
> > index b8713ab..c56cafe 100644
> > --- a/src/mesa/drivers/dri/i965/brw_fs.cpp
> > +++ b/src/mesa/drivers/dri/i965/brw_fs.cpp
> > @@ -5468,6 +5468,7 @@ brw_compile_fs(const struct brw_compiler *compiler, void *log_data,
> >                 char **error_str)
> >  {
> >     nir_shader *shader = nir_shader_clone(mem_ctx, src_shader);
> > +   brw_nir_apply_sampler_key(shader, compiler->devinfo, &key->tex, true);
> 
> This looks like it is part of the post-processing process. In fact, you
> call this right before brw_postprocess_nir() for every stage. Why not
> just add a key parameter to brw_postprocess_nir() and call
> brw_nir_apply_sampler_key from there instead?
> 
> Either way,
> Reviewed-by: Iago Toral Quiroga <itoral at igalia.com>
> 
> >     brw_postprocess_nir(shader, compiler->devinfo, true);
> >  
> >     /* key->alpha_test_func means simulating alpha testing via discards,
> > @@ -5628,6 +5629,7 @@ brw_compile_cs(const struct brw_compiler *compiler, void *log_data,
> >                 char **error_str)
> >  {
> >     nir_shader *shader = nir_shader_clone(mem_ctx, src_shader);
> > +   brw_nir_apply_sampler_key(shader, compiler->devinfo, &key->tex, true);
> >     brw_postprocess_nir(shader, compiler->devinfo, true);
> >  
> >     prog_data->local_size[0] = shader->info.cs.local_size[0];
> > diff --git a/src/mesa/drivers/dri/i965/brw_fs.h b/src/mesa/drivers/dri/i965/brw_fs.h
> > index 2dfcab1..8a181d7 100644
> > --- a/src/mesa/drivers/dri/i965/brw_fs.h
> > +++ b/src/mesa/drivers/dri/i965/brw_fs.h
> > @@ -217,8 +217,6 @@ public:
> >     void emit_interpolation_setup_gen4();
> >     void emit_interpolation_setup_gen6();
> >     void compute_sample_position(fs_reg dst, fs_reg int_sample_pos);
> > -   fs_reg rescale_texcoord(fs_reg coordinate, int coord_components,
> > -                           bool is_rect, uint32_t sampler);
> >     void emit_texture(ir_texture_opcode op,
> >                       const glsl_type *dest_type,
> >                       fs_reg coordinate, int components,
> > @@ -229,7 +227,6 @@ public:
> >                       fs_reg mcs,
> >                       int gather_component,
> >                       bool is_cube_array,
> > -                     bool is_rect,
> >                       uint32_t sampler,
> >                       fs_reg sampler_reg);
> >     fs_reg emit_mcs_fetch(const fs_reg &coordinate, unsigned components,
> > diff --git a/src/mesa/drivers/dri/i965/brw_fs_nir.cpp b/src/mesa/drivers/dri/i965/brw_fs_nir.cpp
> > index 02b9f5b..3d83d7c 100644
> > --- a/src/mesa/drivers/dri/i965/brw_fs_nir.cpp
> > +++ b/src/mesa/drivers/dri/i965/brw_fs_nir.cpp
> > @@ -2411,8 +2411,6 @@ fs_visitor::nir_emit_texture(const fs_builder &bld, nir_tex_instr *instr)
> >  
> >     int gather_component = instr->component;
> >  
> > -   bool is_rect = instr->sampler_dim == GLSL_SAMPLER_DIM_RECT;
> > -
> >     bool is_cube_array = instr->sampler_dim == GLSL_SAMPLER_DIM_CUBE &&
> >                          instr->is_array;
> >  
> > @@ -2549,7 +2547,7 @@ fs_visitor::nir_emit_texture(const fs_builder &bld, nir_tex_instr *instr)
> >     emit_texture(op, dest_type, coordinate, instr->coord_components,
> >                  shadow_comparitor, lod, lod2, lod_components, sample_index,
> >                  tex_offset, mcs, gather_component,
> > -                is_cube_array, is_rect, sampler, sampler_reg);
> > +                is_cube_array, sampler, sampler_reg);
> >  
> >     fs_reg dest = get_nir_dest(instr->dest);
> >     dest.type = this->result.type;
> > diff --git a/src/mesa/drivers/dri/i965/brw_fs_visitor.cpp b/src/mesa/drivers/dri/i965/brw_fs_visitor.cpp
> > index 213c912..faf304c 100644
> > --- a/src/mesa/drivers/dri/i965/brw_fs_visitor.cpp
> > +++ b/src/mesa/drivers/dri/i965/brw_fs_visitor.cpp
> > @@ -79,122 +79,6 @@ fs_visitor::emit_vs_system_value(int location)
> >     return reg;
> >  }
> >  
> > -fs_reg
> > -fs_visitor::rescale_texcoord(fs_reg coordinate, int coord_components,
> > -                             bool is_rect, uint32_t sampler)
> > -{
> > -   bool needs_gl_clamp = true;
> > -   fs_reg scale_x, scale_y;
> > -
> > -   /* The 965 requires the EU to do the normalization of GL rectangle
> > -    * texture coordinates.  We use the program parameter state
> > -    * tracking to get the scaling factor.
> > -    */
> > -   if (is_rect &&
> > -       (devinfo->gen < 6 ||
> > -        (devinfo->gen >= 6 && (key_tex->gl_clamp_mask[0] & (1 << sampler) ||
> > -                               key_tex->gl_clamp_mask[1] & (1 << sampler))))) {
> > -      struct gl_program_parameter_list *params = prog->Parameters;
> > -
> > -
> > -      /* FINISHME: We're failing to recompile our programs when the sampler is
> > -       * updated.  This only matters for the texture rectangle scale
> > -       * parameters (pre-gen6, or gen6+ with GL_CLAMP).
> > -       */
> > -      int tokens[STATE_LENGTH] = {
> > -	 STATE_INTERNAL,
> > -	 STATE_TEXRECT_SCALE,
> > -	 prog->SamplerUnits[sampler],
> > -	 0,
> > -	 0
> > -      };
> > -
> > -      no16("rectangle scale uniform setup not supported on SIMD16\n");
> > -      if (dispatch_width == 16) {
> > -	 return coordinate;
> > -      }
> > -
> > -      GLuint index = _mesa_add_state_reference(params,
> > -					       (gl_state_index *)tokens);
> > -      /* Try to find existing copies of the texrect scale uniforms. */
> > -      for (unsigned i = 0; i < uniforms; i++) {
> > -         if (stage_prog_data->param[i] ==
> > -             &prog->Parameters->ParameterValues[index][0]) {
> > -            scale_x = fs_reg(UNIFORM, i);
> > -            scale_y = fs_reg(UNIFORM, i + 1);
> > -            break;
> > -         }
> > -      }
> > -
> > -      /* If we didn't already set them up, do so now. */
> > -      if (scale_x.file == BAD_FILE) {
> > -         scale_x = fs_reg(UNIFORM, uniforms);
> > -         scale_y = fs_reg(UNIFORM, uniforms + 1);
> > -
> > -         stage_prog_data->param[uniforms++] =
> > -            &prog->Parameters->ParameterValues[index][0];
> > -         stage_prog_data->param[uniforms++] =
> > -            &prog->Parameters->ParameterValues[index][1];
> > -      }
> > -   }
> > -
> > -   /* The 965 requires the EU to do the normalization of GL rectangle
> > -    * texture coordinates.  We use the program parameter state
> > -    * tracking to get the scaling factor.
> > -    */
> > -   if (devinfo->gen < 6 && is_rect) {
> > -      fs_reg dst = fs_reg(GRF, alloc.allocate(coord_components));
> > -      fs_reg src = coordinate;
> > -      coordinate = dst;
> > -
> > -      bld.MUL(dst, src, scale_x);
> > -      dst = offset(dst, bld, 1);
> > -      src = offset(src, bld, 1);
> > -      bld.MUL(dst, src, scale_y);
> > -   } else if (is_rect) {
> > -      /* On gen6+, the sampler handles the rectangle coordinates
> > -       * natively, without needing rescaling.  But that means we have
> > -       * to do GL_CLAMP clamping at the [0, width], [0, height] scale,
> > -       * not [0, 1] like the default case below.
> > -       */
> > -      needs_gl_clamp = false;
> > -
> > -      for (int i = 0; i < 2; i++) {
> > -	 if (key_tex->gl_clamp_mask[i] & (1 << sampler)) {
> > -	    fs_reg chan = coordinate;
> > -	    chan = offset(chan, bld, i);
> > -
> > -            set_condmod(BRW_CONDITIONAL_GE,
> > -                        bld.emit(BRW_OPCODE_SEL, chan, chan, fs_reg(0.0f)));
> > -
> > -	    /* Our parameter comes in as 1.0/width or 1.0/height,
> > -	     * because that's what people normally want for doing
> > -	     * texture rectangle handling.  We need width or height
> > -	     * for clamping, but we don't care enough to make a new
> > -	     * parameter type, so just invert back.
> > -	     */
> > -	    fs_reg limit = vgrf(glsl_type::float_type);
> > -            bld.MOV(limit, i == 0 ? scale_x : scale_y);
> > -            bld.emit(SHADER_OPCODE_RCP, limit, limit);
> > -
> > -            set_condmod(BRW_CONDITIONAL_L,
> > -                        bld.emit(BRW_OPCODE_SEL, chan, chan, limit));
> > -	 }
> > -      }
> > -   }
> > -
> > -   if (coord_components > 0 && needs_gl_clamp) {
> > -      for (int i = 0; i < MIN2(coord_components, 3); i++) {
> > -	 if (key_tex->gl_clamp_mask[i] & (1 << sampler)) {
> > -	    fs_reg chan = coordinate;
> > -	    chan = offset(chan, bld, i);
> > -            set_saturate(true, bld.MOV(chan, chan));
> > -	 }
> > -      }
> > -   }
> > -   return coordinate;
> > -}
> > -
> >  /* Sample from the MCS surface attached to this multisample texture. */
> >  fs_reg
> >  fs_visitor::emit_mcs_fetch(const fs_reg &coordinate, unsigned components,
> > @@ -227,7 +111,6 @@ fs_visitor::emit_texture(ir_texture_opcode op,
> >                           fs_reg mcs,
> >                           int gather_component,
> >                           bool is_cube_array,
> > -                         bool is_rect,
> >                           uint32_t sampler,
> >                           fs_reg sampler_reg)
> >  {
> > @@ -259,14 +142,6 @@ fs_visitor::emit_texture(ir_texture_opcode op,
> >        lod = fs_reg(0u);
> >     }
> >  
> > -   if (coordinate.file != BAD_FILE) {
> > -      /* FINISHME: Texture coordinate rescaling doesn't work with non-constant
> > -       * samplers.  This should only be a problem with GL_CLAMP on Gen7.
> > -       */
> > -      coordinate = rescale_texcoord(coordinate, coord_components, is_rect,
> > -                                    sampler);
> > -   }
> > -
> >     /* Writemasking doesn't eliminate channels on SIMD8 texture
> >      * samples, so don't worry about them.
> >      */
> > diff --git a/src/mesa/drivers/dri/i965/brw_nir.c b/src/mesa/drivers/dri/i965/brw_nir.c
> > index 693b9cd..3999a60 100644
> > --- a/src/mesa/drivers/dri/i965/brw_nir.c
> > +++ b/src/mesa/drivers/dri/i965/brw_nir.c
> > @@ -395,6 +395,29 @@ brw_create_nir(struct brw_context *brw,
> >     return nir;
> >  }
> >  
> > +void
> > +brw_nir_apply_sampler_key(nir_shader *nir,
> > +                          const struct brw_device_info *devinfo,
> > +                          const struct brw_sampler_prog_key_data *key_tex,
> > +                          bool is_scalar)
> > +{
> > +   nir_lower_tex_options tex_options = { 0 };
> > +
> > +   /* Iron Lake and prior require lowering of all rectangle textures */
> > +   if (devinfo->gen < 6)
> > +      tex_options.lower_rect = true;
> > +
> > +   /* Prior to Broadwell, our hardware can't actually do GL_CLAMP */
> > +   if (devinfo->gen < 8) {
> > +      tex_options.saturate_s = key_tex->gl_clamp_mask[0];
> > +      tex_options.saturate_t = key_tex->gl_clamp_mask[1];
> > +      tex_options.saturate_r = key_tex->gl_clamp_mask[2];
> > +   }
> > +
> > +   if (nir_lower_tex(nir, &tex_options))
> > +      nir_optimize(nir, is_scalar);

Based on the code above I guess we only want to execute nir_lower_tex if
gen < 8 too.

Iago

> > +}
> > +
> >  enum brw_reg_type
> >  brw_type_for_nir_type(nir_alu_type type)
> >  {
> > diff --git a/src/mesa/drivers/dri/i965/brw_nir.h b/src/mesa/drivers/dri/i965/brw_nir.h
> > index 1cdfe00..a399992 100644
> > --- a/src/mesa/drivers/dri/i965/brw_nir.h
> > +++ b/src/mesa/drivers/dri/i965/brw_nir.h
> > @@ -90,6 +90,12 @@ void brw_postprocess_nir(nir_shader *nir,
> >                           const struct brw_device_info *devinfo,
> >                           bool is_scalar);
> >  
> > +
> > +void brw_nir_apply_sampler_key(nir_shader *nir,
> > +                               const struct brw_device_info *devinfo,
> > +                               const struct brw_sampler_prog_key_data *key,
> > +                               bool is_scalar);
> > +
> >  enum brw_reg_type brw_type_for_nir_type(nir_alu_type type);
> >  
> >  enum glsl_base_type brw_glsl_base_type_for_nir_type(nir_alu_type type);
> > diff --git a/src/mesa/drivers/dri/i965/brw_vec4.cpp b/src/mesa/drivers/dri/i965/brw_vec4.cpp
> > index 9f75bb6..d207180 100644
> > --- a/src/mesa/drivers/dri/i965/brw_vec4.cpp
> > +++ b/src/mesa/drivers/dri/i965/brw_vec4.cpp
> > @@ -2036,6 +2036,8 @@ brw_compile_vs(const struct brw_compiler *compiler, void *log_data,
> >                 char **error_str)
> >  {
> >     nir_shader *shader = nir_shader_clone(mem_ctx, src_shader);
> > +   brw_nir_apply_sampler_key(shader, compiler->devinfo, &key->tex,
> > +                             compiler->scalar_vs);
> >     brw_postprocess_nir(shader, compiler->devinfo, compiler->scalar_vs);
> >  
> >     const unsigned *assembly = NULL;
> > diff --git a/src/mesa/drivers/dri/i965/brw_vec4_gs_visitor.cpp b/src/mesa/drivers/dri/i965/brw_vec4_gs_visitor.cpp
> > index 92b15d9..4caf54e 100644
> > --- a/src/mesa/drivers/dri/i965/brw_vec4_gs_visitor.cpp
> > +++ b/src/mesa/drivers/dri/i965/brw_vec4_gs_visitor.cpp
> > @@ -616,6 +616,8 @@ brw_compile_gs(const struct brw_compiler *compiler, void *log_data,
> >     c.key = *key;
> >  
> >     nir_shader *shader = nir_shader_clone(mem_ctx, src_shader);
> > +   brw_nir_apply_sampler_key(shader, compiler->devinfo, &key->tex,
> > +                             compiler->scalar_gs);
> >     brw_postprocess_nir(shader, compiler->devinfo, compiler->scalar_gs);
> >  
> >     prog_data->include_primitive_id =
> 




More information about the mesa-dev mailing list