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25 * \file lower_ubo_reference.cpp
27 * IR lower pass to replace dereferences of variables in a uniform
28 * buffer object with usage of ir_binop_ubo_load expressions, each of
29 * which can read data up to the size of a vec4.
31 * This relieves drivers of the responsibility to deal with tricky UBO
32 * layout issues like std140 structures and row_major matrices on
37 #include "ir_builder.h"
38 #include "ir_rvalue_visitor.h"
39 #include "main/macros.h"
40 #include "glsl_parser_extras.h"
42 using namespace ir_builder
;
45 * Determine if a thing being dereferenced is row-major
47 * There is some trickery here.
49 * If the thing being dereferenced is a member of uniform block \b without an
50 * instance name, then the name of the \c ir_variable is the field name of an
51 * interface type. If this field is row-major, then the thing referenced is
54 * If the thing being dereferenced is a member of uniform block \b with an
55 * instance name, then the last dereference in the tree will be an
56 * \c ir_dereference_record. If that record field is row-major, then the
57 * thing referenced is row-major.
60 is_dereferenced_thing_row_major(const ir_rvalue
*deref
)
63 const ir_rvalue
*ir
= deref
;
66 matrix
= matrix
|| ir
->type
->without_array()->is_matrix();
68 switch (ir
->ir_type
) {
69 case ir_type_dereference_array
: {
70 const ir_dereference_array
*const array_deref
=
71 (const ir_dereference_array
*) ir
;
73 ir
= array_deref
->array
;
77 case ir_type_dereference_record
: {
78 const ir_dereference_record
*const record_deref
=
79 (const ir_dereference_record
*) ir
;
81 ir
= record_deref
->record
;
83 const int idx
= ir
->type
->field_index(record_deref
->field
);
86 const enum glsl_matrix_layout matrix_layout
=
87 glsl_matrix_layout(ir
->type
->fields
.structure
[idx
].matrix_layout
);
89 switch (matrix_layout
) {
90 case GLSL_MATRIX_LAYOUT_INHERITED
:
92 case GLSL_MATRIX_LAYOUT_COLUMN_MAJOR
:
94 case GLSL_MATRIX_LAYOUT_ROW_MAJOR
:
95 return matrix
|| deref
->type
->without_array()->is_record();
101 case ir_type_dereference_variable
: {
102 const ir_dereference_variable
*const var_deref
=
103 (const ir_dereference_variable
*) ir
;
105 const enum glsl_matrix_layout matrix_layout
=
106 glsl_matrix_layout(var_deref
->var
->data
.matrix_layout
);
108 switch (matrix_layout
) {
109 case GLSL_MATRIX_LAYOUT_INHERITED
:
112 case GLSL_MATRIX_LAYOUT_COLUMN_MAJOR
:
114 case GLSL_MATRIX_LAYOUT_ROW_MAJOR
:
115 return matrix
|| deref
->type
->without_array()->is_record();
118 unreachable("invalid matrix layout");
127 /* The tree must have ended with a dereference that wasn't an
128 * ir_dereference_variable. That is invalid, and it should be impossible.
130 unreachable("invalid dereference tree");
135 class lower_ubo_reference_visitor
: public ir_rvalue_enter_visitor
{
137 lower_ubo_reference_visitor(struct gl_shader
*shader
)
142 void handle_rvalue(ir_rvalue
**rvalue
);
143 ir_visitor_status
visit_enter(ir_assignment
*ir
);
145 void setup_for_load_or_store(ir_variable
*var
,
148 unsigned *const_offset
,
152 ir_expression
*ubo_load(const struct glsl_type
*type
,
154 ir_call
*ssbo_load(const struct glsl_type
*type
,
157 void check_for_ssbo_store(ir_assignment
*ir
);
158 void write_to_memory(ir_dereference
*deref
,
160 ir_variable
*write_var
,
161 unsigned write_mask
);
162 ir_call
*ssbo_store(ir_rvalue
*deref
, ir_rvalue
*offset
,
163 unsigned write_mask
);
165 void emit_access(bool is_write
, ir_dereference
*deref
,
166 ir_variable
*base_offset
, unsigned int deref_offset
,
167 bool row_major
, int matrix_columns
,
168 unsigned packing
, unsigned write_mask
);
170 ir_visitor_status
visit_enter(class ir_expression
*);
171 ir_expression
*calculate_ssbo_unsized_array_length(ir_expression
*expr
);
172 void check_ssbo_unsized_array_length_expression(class ir_expression
*);
173 void check_ssbo_unsized_array_length_assignment(ir_assignment
*ir
);
175 ir_expression
*process_ssbo_unsized_array_length(ir_rvalue
**,
178 ir_expression
*emit_ssbo_get_buffer_size();
180 unsigned calculate_unsized_array_stride(ir_dereference
*deref
,
183 ir_call
*lower_ssbo_atomic_intrinsic(ir_call
*ir
);
184 ir_call
*check_for_ssbo_atomic_intrinsic(ir_call
*ir
);
185 ir_visitor_status
visit_enter(ir_call
*ir
);
188 struct gl_shader
*shader
;
189 struct gl_uniform_buffer_variable
*ubo_var
;
190 ir_rvalue
*uniform_block
;
192 bool is_shader_storage
;
196 * Determine the name of the interface block field
198 * This is the name of the specific member as it would appear in the
199 * \c gl_uniform_buffer_variable::Name field in the shader's
200 * \c UniformBlocks array.
203 interface_field_name(void *mem_ctx
, char *base_name
, ir_rvalue
*d
,
204 ir_rvalue
**nonconst_block_index
)
206 ir_rvalue
*previous_index
= NULL
;
207 *nonconst_block_index
= NULL
;
210 switch (d
->ir_type
) {
211 case ir_type_dereference_variable
: {
212 ir_dereference_variable
*v
= (ir_dereference_variable
*) d
;
214 && v
->var
->is_interface_instance()
215 && v
->var
->type
->is_array()) {
217 ir_constant
*const_index
= previous_index
->as_constant();
219 *nonconst_block_index
= previous_index
;
220 return ralloc_asprintf(mem_ctx
, "%s[0]", base_name
);
222 return ralloc_asprintf(mem_ctx
,
225 const_index
->get_uint_component(0));
234 case ir_type_dereference_record
: {
235 ir_dereference_record
*r
= (ir_dereference_record
*) d
;
237 d
= r
->record
->as_dereference();
241 case ir_type_dereference_array
: {
242 ir_dereference_array
*a
= (ir_dereference_array
*) d
;
244 d
= a
->array
->as_dereference();
245 previous_index
= a
->array_index
;
249 case ir_type_swizzle
: {
250 ir_swizzle
*s
= (ir_swizzle
*) d
;
252 d
= s
->val
->as_dereference();
256 assert(!"Should not get here.");
261 assert(!"Should not get here.");
266 lower_ubo_reference_visitor::setup_for_load_or_store(ir_variable
*var
,
269 unsigned *const_offset
,
274 /* Determine the name of the interface block */
275 ir_rvalue
*nonconst_block_index
;
276 const char *const field_name
=
277 interface_field_name(mem_ctx
, (char *) var
->get_interface_type()->name
,
278 deref
, &nonconst_block_index
);
280 /* Locate the block by interface name */
281 this->is_shader_storage
= var
->is_in_shader_storage_block();
283 struct gl_uniform_block
**blocks
;
284 if (this->is_shader_storage
) {
285 num_blocks
= shader
->NumShaderStorageBlocks
;
286 blocks
= shader
->ShaderStorageBlocks
;
288 num_blocks
= shader
->NumUniformBlocks
;
289 blocks
= shader
->UniformBlocks
;
291 this->uniform_block
= NULL
;
292 for (unsigned i
= 0; i
< num_blocks
; i
++) {
293 if (strcmp(field_name
, blocks
[i
]->Name
) == 0) {
295 ir_constant
*index
= new(mem_ctx
) ir_constant(i
);
297 if (nonconst_block_index
) {
298 if (nonconst_block_index
->type
!= glsl_type::uint_type
)
299 nonconst_block_index
= i2u(nonconst_block_index
);
300 this->uniform_block
= add(nonconst_block_index
, index
);
302 this->uniform_block
= index
;
305 this->ubo_var
= var
->is_interface_instance()
306 ? &blocks
[i
]->Uniforms
[0] : &blocks
[i
]->Uniforms
[var
->data
.location
];
312 assert(this->uniform_block
);
314 *offset
= new(mem_ctx
) ir_constant(0u);
316 *row_major
= is_dereferenced_thing_row_major(deref
);
319 /* Calculate the offset to the start of the region of the UBO
320 * dereferenced by *rvalue. This may be a variable offset if an
321 * array dereference has a variable index.
324 switch (deref
->ir_type
) {
325 case ir_type_dereference_variable
: {
326 *const_offset
+= ubo_var
->Offset
;
331 case ir_type_dereference_array
: {
332 ir_dereference_array
*deref_array
= (ir_dereference_array
*) deref
;
333 unsigned array_stride
;
334 if (deref_array
->array
->type
->is_matrix() && *row_major
) {
335 /* When loading a vector out of a row major matrix, the
336 * step between the columns (vectors) is the size of a
337 * float, while the step between the rows (elements of a
338 * vector) is handled below in emit_ubo_loads.
341 if (deref_array
->array
->type
->is_double())
343 *matrix_columns
= deref_array
->array
->type
->matrix_columns
;
344 } else if (deref_array
->type
->is_interface()) {
345 /* We're processing an array dereference of an interface instance
346 * array. The thing being dereferenced *must* be a variable
347 * dereference because interfaces cannot be embedded in other
348 * types. In terms of calculating the offsets for the lowering
349 * pass, we don't care about the array index. All elements of an
350 * interface instance array will have the same offsets relative to
351 * the base of the block that backs them.
353 assert(deref_array
->array
->as_dereference_variable());
354 deref
= deref_array
->array
->as_dereference();
357 /* Whether or not the field is row-major (because it might be a
358 * bvec2 or something) does not affect the array itself. We need
359 * to know whether an array element in its entirety is row-major.
361 const bool array_row_major
=
362 is_dereferenced_thing_row_major(deref_array
);
364 /* The array type will give the correct interface packing
367 if (packing
== GLSL_INTERFACE_PACKING_STD430
) {
368 array_stride
= deref_array
->type
->std430_array_stride(array_row_major
);
370 array_stride
= deref_array
->type
->std140_size(array_row_major
);
371 array_stride
= glsl_align(array_stride
, 16);
375 ir_rvalue
*array_index
= deref_array
->array_index
;
376 if (array_index
->type
->base_type
== GLSL_TYPE_INT
)
377 array_index
= i2u(array_index
);
379 ir_constant
*const_index
=
380 array_index
->constant_expression_value(NULL
);
382 *const_offset
+= array_stride
* const_index
->value
.u
[0];
384 *offset
= add(*offset
,
386 new(mem_ctx
) ir_constant(array_stride
)));
388 deref
= deref_array
->array
->as_dereference();
392 case ir_type_dereference_record
: {
393 ir_dereference_record
*deref_record
= (ir_dereference_record
*) deref
;
394 const glsl_type
*struct_type
= deref_record
->record
->type
;
395 unsigned intra_struct_offset
= 0;
397 for (unsigned int i
= 0; i
< struct_type
->length
; i
++) {
398 const glsl_type
*type
= struct_type
->fields
.structure
[i
].type
;
400 ir_dereference_record
*field_deref
= new(mem_ctx
)
401 ir_dereference_record(deref_record
->record
,
402 struct_type
->fields
.structure
[i
].name
);
403 const bool field_row_major
=
404 is_dereferenced_thing_row_major(field_deref
);
406 ralloc_free(field_deref
);
408 unsigned field_align
= 0;
410 if (packing
== GLSL_INTERFACE_PACKING_STD430
)
411 field_align
= type
->std430_base_alignment(field_row_major
);
413 field_align
= type
->std140_base_alignment(field_row_major
);
415 intra_struct_offset
= glsl_align(intra_struct_offset
, field_align
);
417 if (strcmp(struct_type
->fields
.structure
[i
].name
,
418 deref_record
->field
) == 0)
421 if (packing
== GLSL_INTERFACE_PACKING_STD430
)
422 intra_struct_offset
+= type
->std430_size(field_row_major
);
424 intra_struct_offset
+= type
->std140_size(field_row_major
);
426 /* If the field just examined was itself a structure, apply rule
429 * "The structure may have padding at the end; the base offset
430 * of the member following the sub-structure is rounded up to
431 * the next multiple of the base alignment of the structure."
433 if (type
->without_array()->is_record()) {
434 intra_struct_offset
= glsl_align(intra_struct_offset
,
440 *const_offset
+= intra_struct_offset
;
441 deref
= deref_record
->record
->as_dereference();
445 case ir_type_swizzle
: {
446 ir_swizzle
*deref_swizzle
= (ir_swizzle
*) deref
;
448 assert(deref_swizzle
->mask
.num_components
== 1);
450 *const_offset
+= deref_swizzle
->mask
.x
* sizeof(int);
451 deref
= deref_swizzle
->val
->as_dereference();
456 assert(!"not reached");
464 lower_ubo_reference_visitor::handle_rvalue(ir_rvalue
**rvalue
)
469 ir_dereference
*deref
= (*rvalue
)->as_dereference();
473 ir_variable
*var
= deref
->variable_referenced();
474 if (!var
|| !var
->is_in_buffer_block())
477 mem_ctx
= ralloc_parent(shader
->ir
);
479 ir_rvalue
*offset
= NULL
;
480 unsigned const_offset
;
483 unsigned packing
= var
->get_interface_type()->interface_packing
;
485 /* Compute the offset to the start if the dereference as well as other
486 * information we need to configure the write
488 setup_for_load_or_store(var
, deref
,
489 &offset
, &const_offset
,
490 &row_major
, &matrix_columns
,
494 /* Now that we've calculated the offset to the start of the
495 * dereference, walk over the type and emit loads into a temporary.
497 const glsl_type
*type
= (*rvalue
)->type
;
498 ir_variable
*load_var
= new(mem_ctx
) ir_variable(type
,
501 base_ir
->insert_before(load_var
);
503 ir_variable
*load_offset
= new(mem_ctx
) ir_variable(glsl_type::uint_type
,
504 "ubo_load_temp_offset",
506 base_ir
->insert_before(load_offset
);
507 base_ir
->insert_before(assign(load_offset
, offset
));
509 deref
= new(mem_ctx
) ir_dereference_variable(load_var
);
510 emit_access(false, deref
, load_offset
, const_offset
,
511 row_major
, matrix_columns
, packing
, 0);
518 lower_ubo_reference_visitor::ubo_load(const glsl_type
*type
,
521 ir_rvalue
*block_ref
= this->uniform_block
->clone(mem_ctx
, NULL
);
523 ir_expression(ir_binop_ubo_load
,
531 shader_storage_buffer_object(const _mesa_glsl_parse_state
*state
)
533 return state
->ARB_shader_storage_buffer_object_enable
;
537 lower_ubo_reference_visitor::ssbo_store(ir_rvalue
*deref
,
541 exec_list sig_params
;
543 ir_variable
*block_ref
= new(mem_ctx
)
544 ir_variable(glsl_type::uint_type
, "block_ref" , ir_var_function_in
);
545 sig_params
.push_tail(block_ref
);
547 ir_variable
*offset_ref
= new(mem_ctx
)
548 ir_variable(glsl_type::uint_type
, "offset" , ir_var_function_in
);
549 sig_params
.push_tail(offset_ref
);
551 ir_variable
*val_ref
= new(mem_ctx
)
552 ir_variable(deref
->type
, "value" , ir_var_function_in
);
553 sig_params
.push_tail(val_ref
);
555 ir_variable
*writemask_ref
= new(mem_ctx
)
556 ir_variable(glsl_type::uint_type
, "write_mask" , ir_var_function_in
);
557 sig_params
.push_tail(writemask_ref
);
559 ir_function_signature
*sig
= new(mem_ctx
)
560 ir_function_signature(glsl_type::void_type
, shader_storage_buffer_object
);
562 sig
->replace_parameters(&sig_params
);
563 sig
->is_intrinsic
= true;
565 ir_function
*f
= new(mem_ctx
) ir_function("__intrinsic_store_ssbo");
566 f
->add_signature(sig
);
568 exec_list call_params
;
569 call_params
.push_tail(this->uniform_block
->clone(mem_ctx
, NULL
));
570 call_params
.push_tail(offset
->clone(mem_ctx
, NULL
));
571 call_params
.push_tail(deref
->clone(mem_ctx
, NULL
));
572 call_params
.push_tail(new(mem_ctx
) ir_constant(write_mask
));
573 return new(mem_ctx
) ir_call(sig
, NULL
, &call_params
);
577 lower_ubo_reference_visitor::ssbo_load(const struct glsl_type
*type
,
580 exec_list sig_params
;
582 ir_variable
*block_ref
= new(mem_ctx
)
583 ir_variable(glsl_type::uint_type
, "block_ref" , ir_var_function_in
);
584 sig_params
.push_tail(block_ref
);
586 ir_variable
*offset_ref
= new(mem_ctx
)
587 ir_variable(glsl_type::uint_type
, "offset_ref" , ir_var_function_in
);
588 sig_params
.push_tail(offset_ref
);
590 ir_function_signature
*sig
=
591 new(mem_ctx
) ir_function_signature(type
, shader_storage_buffer_object
);
593 sig
->replace_parameters(&sig_params
);
594 sig
->is_intrinsic
= true;
596 ir_function
*f
= new(mem_ctx
) ir_function("__intrinsic_load_ssbo");
597 f
->add_signature(sig
);
599 ir_variable
*result
= new(mem_ctx
)
600 ir_variable(type
, "ssbo_load_result", ir_var_temporary
);
601 base_ir
->insert_before(result
);
602 ir_dereference_variable
*deref_result
= new(mem_ctx
)
603 ir_dereference_variable(result
);
605 exec_list call_params
;
606 call_params
.push_tail(this->uniform_block
->clone(mem_ctx
, NULL
));
607 call_params
.push_tail(offset
->clone(mem_ctx
, NULL
));
609 return new(mem_ctx
) ir_call(sig
, deref_result
, &call_params
);
613 writemask_for_size(unsigned n
)
615 return ((1 << n
) - 1);
619 * Takes a deref and recursively calls itself to break the deref down to the
620 * point that the reads or writes generated are contiguous scalars or vectors.
623 lower_ubo_reference_visitor::emit_access(bool is_write
,
624 ir_dereference
*deref
,
625 ir_variable
*base_offset
,
626 unsigned int deref_offset
,
632 if (deref
->type
->is_record()) {
633 unsigned int field_offset
= 0;
635 for (unsigned i
= 0; i
< deref
->type
->length
; i
++) {
636 const struct glsl_struct_field
*field
=
637 &deref
->type
->fields
.structure
[i
];
638 ir_dereference
*field_deref
=
639 new(mem_ctx
) ir_dereference_record(deref
->clone(mem_ctx
, NULL
),
643 glsl_align(field_offset
,
644 field
->type
->std140_base_alignment(row_major
));
646 emit_access(is_write
, field_deref
, base_offset
,
647 deref_offset
+ field_offset
,
648 row_major
, 1, packing
,
649 writemask_for_size(field_deref
->type
->vector_elements
));
651 field_offset
+= field
->type
->std140_size(row_major
);
656 if (deref
->type
->is_array()) {
657 unsigned array_stride
= packing
== GLSL_INTERFACE_PACKING_STD430
?
658 deref
->type
->fields
.array
->std430_array_stride(row_major
) :
659 glsl_align(deref
->type
->fields
.array
->std140_size(row_major
), 16);
661 for (unsigned i
= 0; i
< deref
->type
->length
; i
++) {
662 ir_constant
*element
= new(mem_ctx
) ir_constant(i
);
663 ir_dereference
*element_deref
=
664 new(mem_ctx
) ir_dereference_array(deref
->clone(mem_ctx
, NULL
),
666 emit_access(is_write
, element_deref
, base_offset
,
667 deref_offset
+ i
* array_stride
,
668 row_major
, 1, packing
,
669 writemask_for_size(element_deref
->type
->vector_elements
));
674 if (deref
->type
->is_matrix()) {
675 for (unsigned i
= 0; i
< deref
->type
->matrix_columns
; i
++) {
676 ir_constant
*col
= new(mem_ctx
) ir_constant(i
);
677 ir_dereference
*col_deref
=
678 new(mem_ctx
) ir_dereference_array(deref
->clone(mem_ctx
, NULL
), col
);
681 /* For a row-major matrix, the next column starts at the next
684 int size_mul
= deref
->type
->is_double() ? 8 : 4;
685 emit_access(is_write
, col_deref
, base_offset
,
686 deref_offset
+ i
* size_mul
,
687 row_major
, deref
->type
->matrix_columns
, packing
,
688 writemask_for_size(col_deref
->type
->vector_elements
));
692 /* std430 doesn't round up vec2 size to a vec4 size */
693 if (packing
== GLSL_INTERFACE_PACKING_STD430
&&
694 deref
->type
->vector_elements
== 2 &&
695 !deref
->type
->is_double()) {
698 /* std140 always rounds the stride of arrays (and matrices) to a
699 * vec4, so matrices are always 16 between columns/rows. With
700 * doubles, they will be 32 apart when there are more than 2 rows.
702 * For both std140 and std430, if the member is a
703 * three-'component vector with components consuming N basic
704 * machine units, the base alignment is 4N. For vec4, base
707 size_mul
= (deref
->type
->is_double() &&
708 deref
->type
->vector_elements
> 2) ? 32 : 16;
711 emit_access(is_write
, col_deref
, base_offset
,
712 deref_offset
+ i
* size_mul
,
713 row_major
, deref
->type
->matrix_columns
, packing
,
714 writemask_for_size(col_deref
->type
->vector_elements
));
720 assert(deref
->type
->is_scalar() || deref
->type
->is_vector());
724 add(base_offset
, new(mem_ctx
) ir_constant(deref_offset
));
726 base_ir
->insert_after(ssbo_store(deref
, offset
, write_mask
));
728 if (!this->is_shader_storage
) {
729 base_ir
->insert_before(assign(deref
->clone(mem_ctx
, NULL
),
730 ubo_load(deref
->type
, offset
)));
732 ir_call
*load_ssbo
= ssbo_load(deref
->type
, offset
);
733 base_ir
->insert_before(load_ssbo
);
734 ir_rvalue
*value
= load_ssbo
->return_deref
->as_rvalue()->clone(mem_ctx
, NULL
);
735 base_ir
->insert_before(assign(deref
->clone(mem_ctx
, NULL
), value
));
739 unsigned N
= deref
->type
->is_double() ? 8 : 4;
741 /* We're dereffing a column out of a row-major matrix, so we
742 * gather the vector from each stored row.
744 assert(deref
->type
->base_type
== GLSL_TYPE_FLOAT
||
745 deref
->type
->base_type
== GLSL_TYPE_DOUBLE
);
746 /* Matrices, row_major or not, are stored as if they were
747 * arrays of vectors of the appropriate size in std140.
748 * Arrays have their strides rounded up to a vec4, so the
749 * matrix stride is always 16. However a double matrix may either be 16
750 * or 32 depending on the number of columns.
752 assert(matrix_columns
<= 4);
753 unsigned matrix_stride
= 0;
754 /* Matrix stride for std430 mat2xY matrices are not rounded up to
755 * vec4 size. From OpenGL 4.3 spec, section 7.6.2.2 "Standard Uniform
758 * "2. If the member is a two- or four-component vector with components
759 * consuming N basic machine units, the base alignment is 2N or 4N,
760 * respectively." [...]
761 * "4. If the member is an array of scalars or vectors, the base alignment
762 * and array stride are set to match the base alignment of a single array
763 * element, according to rules (1), (2), and (3), and rounded up to the
764 * base alignment of a vec4." [...]
765 * "7. If the member is a row-major matrix with C columns and R rows, the
766 * matrix is stored identically to an array of R row vectors with C
767 * components each, according to rule (4)." [...]
768 * "When using the std430 storage layout, shader storage blocks will be
769 * laid out in buffer storage identically to uniform and shader storage
770 * blocks using the std140 layout, except that the base alignment and
771 * stride of arrays of scalars and vectors in rule 4 and of structures in
772 * rule 9 are not rounded up a multiple of the base alignment of a vec4."
774 if (packing
== GLSL_INTERFACE_PACKING_STD430
&& matrix_columns
== 2)
775 matrix_stride
= 2 * N
;
777 matrix_stride
= glsl_align(matrix_columns
* N
, 16);
779 const glsl_type
*deref_type
= deref
->type
->base_type
== GLSL_TYPE_FLOAT
?
780 glsl_type::float_type
: glsl_type::double_type
;
782 for (unsigned i
= 0; i
< deref
->type
->vector_elements
; i
++) {
783 ir_rvalue
*chan_offset
=
785 new(mem_ctx
) ir_constant(deref_offset
+ i
* matrix_stride
));
787 /* If the component is not in the writemask, then don't
790 if (!((1 << i
) & write_mask
))
793 base_ir
->insert_after(ssbo_store(swizzle(deref
, i
, 1), chan_offset
, 1));
795 if (!this->is_shader_storage
) {
796 base_ir
->insert_before(assign(deref
->clone(mem_ctx
, NULL
),
797 ubo_load(deref_type
, chan_offset
),
800 ir_call
*load_ssbo
= ssbo_load(deref_type
, chan_offset
);
801 base_ir
->insert_before(load_ssbo
);
802 ir_rvalue
*value
= load_ssbo
->return_deref
->as_rvalue()->clone(mem_ctx
, NULL
);
803 base_ir
->insert_before(assign(deref
->clone(mem_ctx
, NULL
),
813 lower_ubo_reference_visitor::write_to_memory(ir_dereference
*deref
,
815 ir_variable
*write_var
,
818 ir_rvalue
*offset
= NULL
;
819 unsigned const_offset
;
822 unsigned packing
= var
->get_interface_type()->interface_packing
;
824 /* Compute the offset to the start if the dereference as well as other
825 * information we need to configure the write
827 setup_for_load_or_store(var
, deref
,
828 &offset
, &const_offset
,
829 &row_major
, &matrix_columns
,
833 /* Now emit writes from the temporary to memory */
834 ir_variable
*write_offset
=
835 new(mem_ctx
) ir_variable(glsl_type::uint_type
,
836 "ssbo_store_temp_offset",
839 base_ir
->insert_before(write_offset
);
840 base_ir
->insert_before(assign(write_offset
, offset
));
842 deref
= new(mem_ctx
) ir_dereference_variable(write_var
);
843 emit_access(true, deref
, write_offset
, const_offset
,
844 row_major
, matrix_columns
, packing
, write_mask
);
848 lower_ubo_reference_visitor::visit_enter(ir_expression
*ir
)
850 check_ssbo_unsized_array_length_expression(ir
);
851 return rvalue_visit(ir
);
855 lower_ubo_reference_visitor::calculate_ssbo_unsized_array_length(ir_expression
*expr
)
857 if (expr
->operation
!=
858 ir_expression_operation(ir_unop_ssbo_unsized_array_length
))
861 ir_rvalue
*rvalue
= expr
->operands
[0]->as_rvalue();
863 !rvalue
->type
->is_array() || !rvalue
->type
->is_unsized_array())
866 ir_dereference
*deref
= expr
->operands
[0]->as_dereference();
870 ir_variable
*var
= expr
->operands
[0]->variable_referenced();
871 if (!var
|| !var
->is_in_shader_storage_block())
873 return process_ssbo_unsized_array_length(&rvalue
, deref
, var
);
877 lower_ubo_reference_visitor::check_ssbo_unsized_array_length_expression(ir_expression
*ir
)
880 ir_expression_operation(ir_unop_ssbo_unsized_array_length
)) {
881 /* Don't replace this unop if it is found alone. It is going to be
882 * removed by the optimization passes or replaced if it is part of
883 * an ir_assignment or another ir_expression.
888 for (unsigned i
= 0; i
< ir
->get_num_operands(); i
++) {
889 if (ir
->operands
[i
]->ir_type
!= ir_type_expression
)
891 ir_expression
*expr
= (ir_expression
*) ir
->operands
[i
];
892 ir_expression
*temp
= calculate_ssbo_unsized_array_length(expr
);
897 ir
->operands
[i
] = temp
;
902 lower_ubo_reference_visitor::check_ssbo_unsized_array_length_assignment(ir_assignment
*ir
)
904 if (!ir
->rhs
|| ir
->rhs
->ir_type
!= ir_type_expression
)
907 ir_expression
*expr
= (ir_expression
*) ir
->rhs
;
908 ir_expression
*temp
= calculate_ssbo_unsized_array_length(expr
);
918 lower_ubo_reference_visitor::emit_ssbo_get_buffer_size()
920 ir_rvalue
*block_ref
= this->uniform_block
->clone(mem_ctx
, NULL
);
921 return new(mem_ctx
) ir_expression(ir_unop_get_buffer_size
,
927 lower_ubo_reference_visitor::calculate_unsized_array_stride(ir_dereference
*deref
,
930 unsigned array_stride
= 0;
932 switch (deref
->ir_type
) {
933 case ir_type_dereference_variable
:
935 ir_dereference_variable
*deref_var
= (ir_dereference_variable
*)deref
;
936 const struct glsl_type
*unsized_array_type
= NULL
;
937 /* An unsized array can be sized by other lowering passes, so pick
938 * the first field of the array which has the data type of the unsized
941 unsized_array_type
= deref_var
->var
->type
->fields
.array
;
943 /* Whether or not the field is row-major (because it might be a
944 * bvec2 or something) does not affect the array itself. We need
945 * to know whether an array element in its entirety is row-major.
947 const bool array_row_major
=
948 is_dereferenced_thing_row_major(deref_var
);
950 if (packing
== GLSL_INTERFACE_PACKING_STD430
) {
951 array_stride
= unsized_array_type
->std430_array_stride(array_row_major
);
953 array_stride
= unsized_array_type
->std140_size(array_row_major
);
954 array_stride
= glsl_align(array_stride
, 16);
958 case ir_type_dereference_record
:
960 ir_dereference_record
*deref_record
= (ir_dereference_record
*) deref
;
961 ir_dereference
*interface_deref
=
962 deref_record
->record
->as_dereference();
963 assert(interface_deref
!= NULL
);
964 const struct glsl_type
*interface_type
= interface_deref
->type
;
965 unsigned record_length
= interface_type
->length
;
966 /* Unsized array is always the last element of the interface */
967 const struct glsl_type
*unsized_array_type
=
968 interface_type
->fields
.structure
[record_length
- 1].type
->fields
.array
;
970 const bool array_row_major
=
971 is_dereferenced_thing_row_major(deref_record
);
973 if (packing
== GLSL_INTERFACE_PACKING_STD430
) {
974 array_stride
= unsized_array_type
->std430_array_stride(array_row_major
);
976 array_stride
= unsized_array_type
->std140_size(array_row_major
);
977 array_stride
= glsl_align(array_stride
, 16);
982 unreachable("Unsupported dereference type");
988 lower_ubo_reference_visitor::process_ssbo_unsized_array_length(ir_rvalue
**rvalue
,
989 ir_dereference
*deref
,
992 mem_ctx
= ralloc_parent(*rvalue
);
994 ir_rvalue
*base_offset
= NULL
;
995 unsigned const_offset
;
998 unsigned packing
= var
->get_interface_type()->interface_packing
;
999 int unsized_array_stride
= calculate_unsized_array_stride(deref
, packing
);
1001 /* Compute the offset to the start if the dereference as well as other
1002 * information we need to calculate the length.
1004 setup_for_load_or_store(var
, deref
,
1005 &base_offset
, &const_offset
,
1006 &row_major
, &matrix_columns
,
1009 * max((buffer_object_size - offset_of_array) / stride_of_array, 0)
1011 ir_expression
*buffer_size
= emit_ssbo_get_buffer_size();
1013 ir_expression
*offset_of_array
= new(mem_ctx
)
1014 ir_expression(ir_binop_add
, base_offset
,
1015 new(mem_ctx
) ir_constant(const_offset
));
1016 ir_expression
*offset_of_array_int
= new(mem_ctx
)
1017 ir_expression(ir_unop_u2i
, offset_of_array
);
1019 ir_expression
*sub
= new(mem_ctx
)
1020 ir_expression(ir_binop_sub
, buffer_size
, offset_of_array_int
);
1021 ir_expression
*div
= new(mem_ctx
)
1022 ir_expression(ir_binop_div
, sub
,
1023 new(mem_ctx
) ir_constant(unsized_array_stride
));
1024 ir_expression
*max
= new(mem_ctx
)
1025 ir_expression(ir_binop_max
, div
, new(mem_ctx
) ir_constant(0));
1031 lower_ubo_reference_visitor::check_for_ssbo_store(ir_assignment
*ir
)
1033 if (!ir
|| !ir
->lhs
)
1036 ir_rvalue
*rvalue
= ir
->lhs
->as_rvalue();
1040 ir_dereference
*deref
= ir
->lhs
->as_dereference();
1044 ir_variable
*var
= ir
->lhs
->variable_referenced();
1045 if (!var
|| !var
->is_in_buffer_block())
1048 /* We have a write to a buffer variable, so declare a temporary and rewrite
1049 * the assignment so that the temporary is the LHS.
1051 mem_ctx
= ralloc_parent(shader
->ir
);
1053 const glsl_type
*type
= rvalue
->type
;
1054 ir_variable
*write_var
= new(mem_ctx
) ir_variable(type
,
1057 base_ir
->insert_before(write_var
);
1058 ir
->lhs
= new(mem_ctx
) ir_dereference_variable(write_var
);
1060 /* Now we have to write the value assigned to the temporary back to memory */
1061 write_to_memory(deref
, var
, write_var
, ir
->write_mask
);
1067 lower_ubo_reference_visitor::visit_enter(ir_assignment
*ir
)
1069 check_ssbo_unsized_array_length_assignment(ir
);
1070 check_for_ssbo_store(ir
);
1071 return rvalue_visit(ir
);
1074 /* Lowers the intrinsic call to a new internal intrinsic that swaps the
1075 * access to the buffer variable in the first parameter by an offset
1076 * and block index. This involves creating the new internal intrinsic
1077 * (i.e. the new function signature).
1080 lower_ubo_reference_visitor::lower_ssbo_atomic_intrinsic(ir_call
*ir
)
1082 /* SSBO atomics usually have 2 parameters, the buffer variable and an
1083 * integer argument. The exception is CompSwap, that has an additional
1084 * integer parameter.
1086 int param_count
= ir
->actual_parameters
.length();
1087 assert(param_count
== 2 || param_count
== 3);
1089 /* First argument must be a scalar integer buffer variable */
1090 exec_node
*param
= ir
->actual_parameters
.get_head();
1091 ir_instruction
*inst
= (ir_instruction
*) param
;
1092 assert(inst
->ir_type
== ir_type_dereference_variable
||
1093 inst
->ir_type
== ir_type_dereference_array
||
1094 inst
->ir_type
== ir_type_dereference_record
||
1095 inst
->ir_type
== ir_type_swizzle
);
1097 ir_rvalue
*deref
= (ir_rvalue
*) inst
;
1098 assert(deref
->type
->is_scalar() && deref
->type
->is_integer());
1100 ir_variable
*var
= deref
->variable_referenced();
1103 /* Compute the offset to the start if the dereference and the
1106 mem_ctx
= ralloc_parent(shader
->ir
);
1108 ir_rvalue
*offset
= NULL
;
1109 unsigned const_offset
;
1112 unsigned packing
= var
->get_interface_type()->interface_packing
;
1114 setup_for_load_or_store(var
, deref
,
1115 &offset
, &const_offset
,
1116 &row_major
, &matrix_columns
,
1120 assert(matrix_columns
== 1);
1122 ir_rvalue
*deref_offset
=
1123 add(offset
, new(mem_ctx
) ir_constant(const_offset
));
1124 ir_rvalue
*block_index
= this->uniform_block
->clone(mem_ctx
, NULL
);
1126 /* Create the new internal function signature that will take a block
1127 * index and offset instead of a buffer variable
1129 exec_list sig_params
;
1130 ir_variable
*sig_param
= new(mem_ctx
)
1131 ir_variable(glsl_type::uint_type
, "block_ref" , ir_var_function_in
);
1132 sig_params
.push_tail(sig_param
);
1134 sig_param
= new(mem_ctx
)
1135 ir_variable(glsl_type::uint_type
, "offset" , ir_var_function_in
);
1136 sig_params
.push_tail(sig_param
);
1138 const glsl_type
*type
= deref
->type
->base_type
== GLSL_TYPE_INT
?
1139 glsl_type::int_type
: glsl_type::uint_type
;
1140 sig_param
= new(mem_ctx
)
1141 ir_variable(type
, "data1", ir_var_function_in
);
1142 sig_params
.push_tail(sig_param
);
1144 if (param_count
== 3) {
1145 sig_param
= new(mem_ctx
)
1146 ir_variable(type
, "data2", ir_var_function_in
);
1147 sig_params
.push_tail(sig_param
);
1150 ir_function_signature
*sig
=
1151 new(mem_ctx
) ir_function_signature(deref
->type
,
1152 shader_storage_buffer_object
);
1154 sig
->replace_parameters(&sig_params
);
1155 sig
->is_intrinsic
= true;
1158 sprintf(func_name
, "%s_internal", ir
->callee_name());
1159 ir_function
*f
= new(mem_ctx
) ir_function(func_name
);
1160 f
->add_signature(sig
);
1162 /* Now, create the call to the internal intrinsic */
1163 exec_list call_params
;
1164 call_params
.push_tail(block_index
);
1165 call_params
.push_tail(deref_offset
);
1166 param
= ir
->actual_parameters
.get_head()->get_next();
1167 ir_rvalue
*param_as_rvalue
= ((ir_instruction
*) param
)->as_rvalue();
1168 call_params
.push_tail(param_as_rvalue
->clone(mem_ctx
, NULL
));
1169 if (param_count
== 3) {
1170 param
= param
->get_next();
1171 param_as_rvalue
= ((ir_instruction
*) param
)->as_rvalue();
1172 call_params
.push_tail(param_as_rvalue
->clone(mem_ctx
, NULL
));
1174 ir_dereference_variable
*return_deref
=
1175 ir
->return_deref
->clone(mem_ctx
, NULL
);
1176 return new(mem_ctx
) ir_call(sig
, return_deref
, &call_params
);
1180 lower_ubo_reference_visitor::check_for_ssbo_atomic_intrinsic(ir_call
*ir
)
1182 const char *callee
= ir
->callee_name();
1183 if (!strcmp("__intrinsic_ssbo_atomic_add", callee
) ||
1184 !strcmp("__intrinsic_ssbo_atomic_min", callee
) ||
1185 !strcmp("__intrinsic_ssbo_atomic_max", callee
) ||
1186 !strcmp("__intrinsic_ssbo_atomic_and", callee
) ||
1187 !strcmp("__intrinsic_ssbo_atomic_or", callee
) ||
1188 !strcmp("__intrinsic_ssbo_atomic_xor", callee
) ||
1189 !strcmp("__intrinsic_ssbo_atomic_exchange", callee
) ||
1190 !strcmp("__intrinsic_ssbo_atomic_comp_swap", callee
)) {
1191 return lower_ssbo_atomic_intrinsic(ir
);
1199 lower_ubo_reference_visitor::visit_enter(ir_call
*ir
)
1201 ir_call
*new_ir
= check_for_ssbo_atomic_intrinsic(ir
);
1204 base_ir
->replace_with(new_ir
);
1205 return visit_continue_with_parent
;
1208 return rvalue_visit(ir
);
1212 } /* unnamed namespace */
1215 lower_ubo_reference(struct gl_shader
*shader
, exec_list
*instructions
)
1217 lower_ubo_reference_visitor
v(shader
);
1219 /* Loop over the instructions lowering references, because we take
1220 * a deref of a UBO array using a UBO dereference as the index will
1221 * produce a collection of instructions all of which have cloned
1222 * UBO dereferences for that array index.
1226 visit_list_elements(&v
, instructions
);
1227 } while (v
.progress
);