[Mesa-dev] [PATCH v5 28/70] glsl: add std430 interface packing support to ssbo related operations

Jordan Justen jordan.l.justen at intel.com
Wed Sep 16 00:46:13 PDT 2015


On 2015-09-10 06:35:44, Iago Toral Quiroga wrote:
> From: Samuel Iglesias Gonsalvez <siglesias at igalia.com>
> 
> v2:
> - Get interface packing information from interface's type, not the variable type.
> - Simplify is_std430 condition in emit_access() for readability (Jordan)
> - Add a commment explaing why array of three-component vector case is different

Lines a bit long.

>   in std430 than the rest of cases.
> - Add calls to std430_array_stride().
> 
> Signed-off-by: Samuel Iglesias Gonsalvez <siglesias at igalia.com>
> ---
>  src/glsl/lower_ubo_reference.cpp | 102 ++++++++++++++++++++++++++++++---------
>  1 file changed, 78 insertions(+), 24 deletions(-)
> 
> diff --git a/src/glsl/lower_ubo_reference.cpp b/src/glsl/lower_ubo_reference.cpp
> index 8694383..7e45a26 100644
> --- a/src/glsl/lower_ubo_reference.cpp
> +++ b/src/glsl/lower_ubo_reference.cpp
> @@ -147,7 +147,8 @@ public:
>                                  ir_rvalue **offset,
>                                  unsigned *const_offset,
>                                  bool *row_major,
> -                                int *matrix_columns);
> +                                int *matrix_columns,
> +                                unsigned packing);
>     ir_expression *ubo_load(const struct glsl_type *type,
>                            ir_rvalue *offset);
>     ir_call *ssbo_load(const struct glsl_type *type,
> @@ -164,7 +165,7 @@ public:
>     void emit_access(bool is_write, ir_dereference *deref,
>                      ir_variable *base_offset, unsigned int deref_offset,
>                      bool row_major, int matrix_columns,
> -                    unsigned write_mask);
> +                    bool is_std430, unsigned write_mask);
>  
>     ir_visitor_status visit_enter(class ir_expression *);
>     ir_expression *calculate_ssbo_unsized_array_length(ir_expression *expr);
> @@ -176,7 +177,8 @@ public:
>                                                      ir_variable *);
>     ir_expression *emit_ssbo_get_buffer_size();
>  
> -   unsigned calculate_unsized_array_stride(ir_dereference *deref);
> +   unsigned calculate_unsized_array_stride(ir_dereference *deref,
> +                                           unsigned packing);
>  
>     void *mem_ctx;
>     struct gl_shader *shader;
> @@ -257,7 +259,8 @@ lower_ubo_reference_visitor::setup_for_load_or_store(ir_variable *var,
>                                                       ir_rvalue **offset,
>                                                       unsigned *const_offset,
>                                                       bool *row_major,
> -                                                     int *matrix_columns)
> +                                                     int *matrix_columns,
> +                                                     unsigned packing)
>  {
>     /* Determine the name of the interface block */
>     ir_rvalue *nonconst_block_index;
> @@ -343,8 +346,15 @@ lower_ubo_reference_visitor::setup_for_load_or_store(ir_variable *var,
>              const bool array_row_major =
>                 is_dereferenced_thing_row_major(deref_array);
>  
> -            array_stride = deref_array->type->std140_size(array_row_major);
> -            array_stride = glsl_align(array_stride, 16);
> +            /* The array type will give the correct interface packing
> +             * information
> +             */
> +            if (packing == GLSL_INTERFACE_PACKING_STD430) {
> +               array_stride = deref_array->type->std430_array_stride(array_row_major);
> +            } else {
> +               array_stride = deref_array->type->std140_size(array_row_major);
> +               array_stride = glsl_align(array_stride, 16);
> +            }
>           }
>  
>           ir_rvalue *array_index = deref_array->array_index;
> @@ -380,7 +390,12 @@ lower_ubo_reference_visitor::setup_for_load_or_store(ir_variable *var,
>  
>              ralloc_free(field_deref);
>  
> -            unsigned field_align = type->std140_base_alignment(field_row_major);
> +            unsigned field_align = 0;
> +
> +            if (packing == GLSL_INTERFACE_PACKING_STD430)
> +               field_align = type->std430_base_alignment(field_row_major);
> +            else
> +               field_align = type->std140_base_alignment(field_row_major);
>  
>              intra_struct_offset = glsl_align(intra_struct_offset, field_align);
>  
> @@ -388,7 +403,10 @@ lower_ubo_reference_visitor::setup_for_load_or_store(ir_variable *var,
>                         deref_record->field) == 0)
>                 break;
>  
> -            intra_struct_offset += type->std140_size(field_row_major);
> +            if (packing == GLSL_INTERFACE_PACKING_STD430)
> +               intra_struct_offset += type->std430_size(field_row_major);
> +            else
> +               intra_struct_offset += type->std140_size(field_row_major);
>  
>              /* If the field just examined was itself a structure, apply rule
>               * #9:
> @@ -437,13 +455,15 @@ lower_ubo_reference_visitor::handle_rvalue(ir_rvalue **rvalue)
>     unsigned const_offset;
>     bool row_major;
>     int matrix_columns;
> +   unsigned packing = var->get_interface_type()->interface_packing;
>  
>     /* Compute the offset to the start if the dereference as well as other
>      * information we need to configure the write
>      */
>     setup_for_load_or_store(var, deref,
>                             &offset, &const_offset,
> -                           &row_major, &matrix_columns);
> +                           &row_major, &matrix_columns,
> +                           packing);
>     assert(offset);
>  
>     /* Now that we've calculated the offset to the start of the
> @@ -463,7 +483,7 @@ lower_ubo_reference_visitor::handle_rvalue(ir_rvalue **rvalue)
>  
>     deref = new(mem_ctx) ir_dereference_variable(load_var);
>     emit_access(false, deref, load_offset, const_offset,
> -               row_major, matrix_columns, 0);
> +               row_major, matrix_columns, false, 0);
>     *rvalue = deref;
>  
>     progress = true;
> @@ -581,6 +601,7 @@ lower_ubo_reference_visitor::emit_access(bool is_write,
>                                           unsigned int deref_offset,
>                                           bool row_major,
>                                           int matrix_columns,
> +                                         bool is_std430,
>                                           unsigned write_mask)
>  {
>     if (deref->type->is_record()) {
> @@ -599,7 +620,7 @@ lower_ubo_reference_visitor::emit_access(bool is_write,
>  
>           emit_access(is_write, field_deref, base_offset,
>                       deref_offset + field_offset,
> -                     row_major, 1,
> +                     row_major, 1, is_std430,
>                       writemask_for_size(field_deref->type->vector_elements));
>  
>           field_offset += field->type->std140_size(row_major);
> @@ -608,7 +629,8 @@ lower_ubo_reference_visitor::emit_access(bool is_write,
>     }
>  
>     if (deref->type->is_array()) {
> -      unsigned array_stride =
> +      unsigned array_stride = is_std430 ?
> +         deref->type->fields.array->std430_array_stride(row_major) :
>           glsl_align(deref->type->fields.array->std140_size(row_major), 16);
>  
>        for (unsigned i = 0; i < deref->type->length; i++) {
> @@ -618,7 +640,7 @@ lower_ubo_reference_visitor::emit_access(bool is_write,
>                                                element);
>           emit_access(is_write, element_deref, base_offset,
>                       deref_offset + i * array_stride,
> -                     row_major, 1,
> +                     row_major, 1, is_std430,
>                       writemask_for_size(element_deref->type->vector_elements));
>        }
>        return;
> @@ -637,7 +659,7 @@ lower_ubo_reference_visitor::emit_access(bool is_write,
>              int size_mul = deref->type->is_double() ? 8 : 4;
>              emit_access(is_write, col_deref, base_offset,
>                          deref_offset + i * size_mul,
> -                        row_major, deref->type->matrix_columns,
> +                        row_major, deref->type->matrix_columns, is_std430,
>                          writemask_for_size(col_deref->type->vector_elements));
>           } else {
>              /* std140 always rounds the stride of arrays (and matrices) to a
> @@ -646,9 +668,26 @@ lower_ubo_reference_visitor::emit_access(bool is_write,
>               */
>              int size_mul = (deref->type->is_double() &&
>                              deref->type->vector_elements > 2) ? 32 : 16;
> +
> +            /* std430 doesn't round up to a vec4 */
> +            if (is_std430) {
> +               if (deref->type->vector_elements <= 2) {
> +                  size_mul = deref->type->is_double() ?
> +                     8 * deref->type->vector_elements :
> +                     4 * deref->type->vector_elements;
> +               } else {
> +                  /* If the member is a three-component vector with components
> +                   * consuming N basic machine units, the base alignment is 4N.
> +                   * For vec4, base alignment is 4N.
> +                   */
> +                  size_mul = (deref->type->is_double() &&
> +                              deref->type->vector_elements > 2) ? 32 : 16;

Notice size_mul is reassigned the same value here as above?

Would this work?

            int size_mul;

            if (is_std430 && deref->type->vector_elements == 2 &&
                !deref->type->is_double()) {
               size_mul = 8;
            } else {
               size_mul = (deref->type->is_double() &&
                           deref->type->vector_elements > 2) ? 32 : 16;
            }

I'm assuming vector_elements can't be 1. I'm not certain on that, but,
https://www.opengl.org/wiki/Data_Type_(GLSL)#Matrices seems to agree
with this.

-Jordan

> +               }
> +            }
> +
>              emit_access(is_write, col_deref, base_offset,
>                          deref_offset + i * size_mul,
> -                        row_major, deref->type->matrix_columns,
> +                        row_major, deref->type->matrix_columns, is_std430,
>                          writemask_for_size(col_deref->type->vector_elements));
>           }
>        }
> @@ -727,13 +766,16 @@ lower_ubo_reference_visitor::write_to_memory(ir_dereference *deref,
>     unsigned const_offset;
>     bool row_major;
>     int matrix_columns;
> +   unsigned packing = var->get_interface_type()->interface_packing;
> +   bool is_std430 = packing == GLSL_INTERFACE_PACKING_STD430;
>  
>     /* Compute the offset to the start if the dereference as well as other
>      * information we need to configure the write
>      */
>     setup_for_load_or_store(var, deref,
>                             &offset, &const_offset,
> -                           &row_major, &matrix_columns);
> +                           &row_major, &matrix_columns,
> +                           packing);
>     assert(offset);
>  
>     /* Now emit writes from the temporary to memory */
> @@ -747,7 +789,7 @@ lower_ubo_reference_visitor::write_to_memory(ir_dereference *deref,
>  
>     deref = new(mem_ctx) ir_dereference_variable(write_var);
>     emit_access(true, deref, write_offset, const_offset,
> -               row_major, matrix_columns, write_mask);
> +               row_major, matrix_columns, is_std430, write_mask);
>  }
>  
>  ir_visitor_status
> @@ -830,7 +872,8 @@ lower_ubo_reference_visitor::emit_ssbo_get_buffer_size()
>  }
>  
>  unsigned
> -lower_ubo_reference_visitor::calculate_unsized_array_stride(ir_dereference *deref)
> +lower_ubo_reference_visitor::calculate_unsized_array_stride(ir_dereference *deref,
> +                                                            unsigned packing)
>  {
>     unsigned array_stride = 0;
>  
> @@ -852,8 +895,12 @@ lower_ubo_reference_visitor::calculate_unsized_array_stride(ir_dereference *dere
>        const bool array_row_major =
>           is_dereferenced_thing_row_major(deref_var);
>  
> -      array_stride = unsized_array_type->std140_size(array_row_major);
> -      array_stride = glsl_align(array_stride, 16);
> +      if (packing == GLSL_INTERFACE_PACKING_STD430) {
> +         array_stride = unsized_array_type->std430_array_stride(array_row_major);
> +      } else {
> +         array_stride = unsized_array_type->std140_size(array_row_major);
> +         array_stride = glsl_align(array_stride, 16);
> +      }
>        break;
>     }
>     case ir_type_dereference_record:
> @@ -868,8 +915,13 @@ lower_ubo_reference_visitor::calculate_unsized_array_stride(ir_dereference *dere
>  
>        const bool array_row_major =
>           is_dereferenced_thing_row_major(deref_record);
> -      array_stride = unsized_array_type->std140_size(array_row_major);
> -      array_stride = glsl_align(array_stride, 16);
> +
> +      if (packing == GLSL_INTERFACE_PACKING_STD430) {
> +         array_stride = unsized_array_type->std430_array_stride(array_row_major);
> +      } else {
> +         array_stride = unsized_array_type->std140_size(array_row_major);
> +         array_stride = glsl_align(array_stride, 16);
> +      }
>        break;
>     }
>     default:
> @@ -889,14 +941,16 @@ lower_ubo_reference_visitor::process_ssbo_unsized_array_length(ir_rvalue **rvalu
>     unsigned const_offset;
>     bool row_major;
>     int matrix_columns;
> -   int unsized_array_stride = calculate_unsized_array_stride(deref);
> +   unsigned packing = var->get_interface_type()->interface_packing;
> +   int unsized_array_stride = calculate_unsized_array_stride(deref, packing);
>  
>     /* Compute the offset to the start if the dereference as well as other
>      * information we need to calculate the length.
>      */
>     setup_for_load_or_store(var, deref,
>                             &base_offset, &const_offset,
> -                           &row_major, &matrix_columns);
> +                           &row_major, &matrix_columns,
> +                           packing);
>     /* array.length() =
>      *  max((buffer_object_size - offset_of_array) / stride_of_array, 0)
>      */
> -- 
> 1.9.1
> 


More information about the mesa-dev mailing list