From 750c694474776fd545262aaf3190ccd92d6bb0ec Mon Sep 17 00:00:00 2001 From: Samuel Iglesias Gonsalvez Date: Wed, 8 Jul 2015 17:42:14 +0200 Subject: glsl: implement unsized array length MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit v2: - Reduce the number of lines over 80 character line width limit. (Thomas Hellan) v3: - Inject the formula to compute the array length in the IR, backends only need to provide the buffer size (Curro) - Create an auxiliary function to simplify code (Jordan Justen) - Rename variables (Jordan Justen) Signed-off-by: Samuel Iglesias Gonsalvez Reviewed-by: Kristian Høgsberg --- src/glsl/lower_ubo_reference.cpp | 182 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 182 insertions(+) diff --git a/src/glsl/lower_ubo_reference.cpp b/src/glsl/lower_ubo_reference.cpp index 8b0810781fe..8694383c4ed 100644 --- a/src/glsl/lower_ubo_reference.cpp +++ b/src/glsl/lower_ubo_reference.cpp @@ -166,6 +166,18 @@ public: bool row_major, int matrix_columns, unsigned write_mask); + ir_visitor_status visit_enter(class ir_expression *); + ir_expression *calculate_ssbo_unsized_array_length(ir_expression *expr); + void check_ssbo_unsized_array_length_expression(class ir_expression *); + void check_ssbo_unsized_array_length_assignment(ir_assignment *ir); + + ir_expression *process_ssbo_unsized_array_length(ir_rvalue **, + ir_dereference *, + ir_variable *); + ir_expression *emit_ssbo_get_buffer_size(); + + unsigned calculate_unsized_array_stride(ir_dereference *deref); + void *mem_ctx; struct gl_shader *shader; struct gl_uniform_buffer_variable *ubo_var; @@ -738,6 +750,175 @@ lower_ubo_reference_visitor::write_to_memory(ir_dereference *deref, row_major, matrix_columns, write_mask); } +ir_visitor_status +lower_ubo_reference_visitor::visit_enter(ir_expression *ir) +{ + check_ssbo_unsized_array_length_expression(ir); + return rvalue_visit(ir); +} + +ir_expression * +lower_ubo_reference_visitor::calculate_ssbo_unsized_array_length(ir_expression *expr) +{ + if (expr->operation != + ir_expression_operation(ir_unop_ssbo_unsized_array_length)) + return NULL; + + ir_rvalue *rvalue = expr->operands[0]->as_rvalue(); + if (!rvalue || + !rvalue->type->is_array() || !rvalue->type->is_unsized_array()) + return NULL; + + ir_dereference *deref = expr->operands[0]->as_dereference(); + if (!deref) + return NULL; + + ir_variable *var = expr->operands[0]->variable_referenced(); + if (!var || !var->is_in_shader_storage_block()) + return NULL; + return process_ssbo_unsized_array_length(&rvalue, deref, var); +} + +void +lower_ubo_reference_visitor::check_ssbo_unsized_array_length_expression(ir_expression *ir) +{ + if (ir->operation == + ir_expression_operation(ir_unop_ssbo_unsized_array_length)) { + /* Don't replace this unop if it is found alone. It is going to be + * removed by the optimization passes or replaced if it is part of + * an ir_assignment or another ir_expression. + */ + return; + } + + for (unsigned i = 0; i < ir->get_num_operands(); i++) { + if (ir->operands[i]->ir_type != ir_type_expression) + continue; + ir_expression *expr = (ir_expression *) ir->operands[i]; + ir_expression *temp = calculate_ssbo_unsized_array_length(expr); + if (!temp) + continue; + + delete expr; + ir->operands[i] = temp; + } +} + +void +lower_ubo_reference_visitor::check_ssbo_unsized_array_length_assignment(ir_assignment *ir) +{ + if (!ir->rhs || ir->rhs->ir_type != ir_type_expression) + return; + + ir_expression *expr = (ir_expression *) ir->rhs; + ir_expression *temp = calculate_ssbo_unsized_array_length(expr); + if (!temp) + return; + + delete expr; + ir->rhs = temp; + return; +} + +ir_expression * +lower_ubo_reference_visitor::emit_ssbo_get_buffer_size() +{ + ir_rvalue *block_ref = this->uniform_block->clone(mem_ctx, NULL); + return new(mem_ctx) ir_expression(ir_unop_get_buffer_size, + glsl_type::int_type, + block_ref); +} + +unsigned +lower_ubo_reference_visitor::calculate_unsized_array_stride(ir_dereference *deref) +{ + unsigned array_stride = 0; + + switch (deref->ir_type) { + case ir_type_dereference_variable: + { + ir_dereference_variable *deref_var = (ir_dereference_variable *)deref; + const struct glsl_type *unsized_array_type = NULL; + /* An unsized array can be sized by other lowering passes, so pick + * the first field of the array which has the data type of the unsized + * array. + */ + unsized_array_type = deref_var->var->type->fields.array; + + /* Whether or not the field is row-major (because it might be a + * bvec2 or something) does not affect the array itself. We need + * to know whether an array element in its entirety is row-major. + */ + 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); + break; + } + case ir_type_dereference_record: + { + ir_dereference_record *deref_record = (ir_dereference_record *) deref; + const struct glsl_type *deref_record_type = + deref_record->record->as_dereference()->type; + unsigned record_length = deref_record_type->length; + /* Unsized array is always the last element of the interface */ + const struct glsl_type *unsized_array_type = + deref_record_type->fields.structure[record_length - 1].type->fields.array; + + 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); + break; + } + default: + unreachable("Unsupported dereference type"); + } + return array_stride; +} + +ir_expression * +lower_ubo_reference_visitor::process_ssbo_unsized_array_length(ir_rvalue **rvalue, + ir_dereference *deref, + ir_variable *var) +{ + mem_ctx = ralloc_parent(*rvalue); + + ir_rvalue *base_offset = NULL; + unsigned const_offset; + bool row_major; + int matrix_columns; + int unsized_array_stride = calculate_unsized_array_stride(deref); + + /* 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); + /* array.length() = + * max((buffer_object_size - offset_of_array) / stride_of_array, 0) + */ + ir_expression *buffer_size = emit_ssbo_get_buffer_size(); + + ir_expression *offset_of_array = new(mem_ctx) + ir_expression(ir_binop_add, base_offset, + new(mem_ctx) ir_constant(const_offset)); + ir_expression *offset_of_array_int = new(mem_ctx) + ir_expression(ir_unop_u2i, offset_of_array); + + ir_expression *sub = new(mem_ctx) + ir_expression(ir_binop_sub, buffer_size, offset_of_array_int); + ir_expression *div = new(mem_ctx) + ir_expression(ir_binop_div, sub, + new(mem_ctx) ir_constant(unsized_array_stride)); + ir_expression *max = new(mem_ctx) + ir_expression(ir_binop_max, div, new(mem_ctx) ir_constant(0)); + + return max; +} + void lower_ubo_reference_visitor::check_for_ssbo_store(ir_assignment *ir) { @@ -777,6 +958,7 @@ lower_ubo_reference_visitor::check_for_ssbo_store(ir_assignment *ir) ir_visitor_status lower_ubo_reference_visitor::visit_enter(ir_assignment *ir) { + check_ssbo_unsized_array_length_assignment(ir); check_for_ssbo_store(ir); return rvalue_visit(ir); } -- cgit v1.2.3