diff options
| -rw-r--r-- | src/glsl/lower_ubo_reference.cpp | 56 |
1 files changed, 54 insertions, 2 deletions
diff --git a/src/glsl/lower_ubo_reference.cpp b/src/glsl/lower_ubo_reference.cpp index b82d800eefb..8ec83465b69 100644 --- a/src/glsl/lower_ubo_reference.cpp +++ b/src/glsl/lower_ubo_reference.cpp @@ -155,6 +155,7 @@ public: ir_rvalue *offset); bool check_for_buffer_array_copy(ir_assignment *ir); + bool check_for_buffer_struct_copy(ir_assignment *ir); void check_for_ssbo_store(ir_assignment *ir); void write_to_memory(ir_dereference *deref, ir_variable *var, @@ -1190,12 +1191,60 @@ lower_ubo_reference_visitor::check_for_buffer_array_copy(ir_assignment *ir) return true; } +bool +lower_ubo_reference_visitor::check_for_buffer_struct_copy(ir_assignment *ir) +{ + if (!ir || !ir->lhs || !ir->rhs) + return false; + + /* LHS and RHS must be records */ + if (!ir->lhs->type->is_record() || !ir->rhs->type->is_record()) + return false; + + /* RHS must be a buffer-backed variable. This is what can cause the problem + * since it would lead to a series of loads that need to live until we + * see the writes to the LHS. + */ + ir_variable *rhs_var = ir->rhs->variable_referenced(); + if (!rhs_var || !is_buffer_backed_variable(rhs_var)) + return false; + + /* Split the struct copy into individual element copies to reduce + * register pressure + */ + ir_dereference *rhs_deref = ir->rhs->as_dereference(); + if (!rhs_deref) + return false; + + ir_dereference *lhs_deref = ir->lhs->as_dereference(); + if (!lhs_deref) + return false; + + assert(lhs_deref->type->record_compare(rhs_deref->type)); + mem_ctx = ralloc_parent(shader->ir); + + for (unsigned i = 0; i < lhs_deref->type->length; i++) { + const char *field_name = lhs_deref->type->fields.structure[i].name; + ir_dereference *lhs_field = + new(mem_ctx) ir_dereference_record(lhs_deref->clone(mem_ctx, NULL), + field_name); + ir_dereference *rhs_field = + new(mem_ctx) ir_dereference_record(rhs_deref->clone(mem_ctx, NULL), + field_name); + ir->insert_after(assign(lhs_field, rhs_field)); + } + + ir->remove(); + progress = true; + return true; +} + ir_visitor_status lower_ubo_reference_visitor::visit_enter(ir_assignment *ir) { - /* Array copies could involve large amounts of load/store + /* Array and struct copies could involve large amounts of load/store * operations. To improve register pressure we want to special-case - * these and split array copies into individual element copies. + * these and split them into individual element copies. * This way we avoid emitting all the loads for the RHS first and * all the writes for the LHS second and register usage is more * efficient. @@ -1203,6 +1252,9 @@ lower_ubo_reference_visitor::visit_enter(ir_assignment *ir) if (check_for_buffer_array_copy(ir)) return visit_continue_with_parent; + if (check_for_buffer_struct_copy(ir)) + return visit_continue_with_parent; + check_ssbo_unsized_array_length_assignment(ir); check_for_ssbo_store(ir); return rvalue_visit(ir); |