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Diffstat (limited to 'src/glsl/opt_structure_splitting.cpp')
-rw-r--r-- | src/glsl/opt_structure_splitting.cpp | 361 |
1 files changed, 361 insertions, 0 deletions
diff --git a/src/glsl/opt_structure_splitting.cpp b/src/glsl/opt_structure_splitting.cpp new file mode 100644 index 00000000000..ff3ec936eb8 --- /dev/null +++ b/src/glsl/opt_structure_splitting.cpp @@ -0,0 +1,361 @@ +/* + * Copyright © 2010 Intel Corporation + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the "Software"), + * to deal in the Software without restriction, including without limitation + * the rights to use, copy, modify, merge, publish, distribute, sublicense, + * and/or sell copies of the Software, and to permit persons to whom the + * Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice (including the next + * paragraph) shall be included in all copies or substantial portions of the + * Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING + * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER + * DEALINGS IN THE SOFTWARE. + */ + +/** + * \file ir_structure_splitting.cpp + * + * If a structure is only ever referenced by its components, then + * split those components out to individual variables so they can be + * handled normally by other optimization passes. + * + * This skips structures like uniforms, which need to be accessible as + * structures for their access by the GL. + */ + +#include "ir.h" +#include "ir_visitor.h" +#include "ir_print_visitor.h" +#include "ir_rvalue_visitor.h" +#include "glsl_types.h" + +static bool debug = false; + +// XXX using variable_entry2 here to avoid collision (MSVC multiply-defined +// function) with the variable_entry class seen in ir_variable_refcount.h +// Perhaps we can use the one in ir_variable_refcount.h and make this class +// here go away? +class variable_entry2 : public exec_node +{ +public: + variable_entry2(ir_variable *var) + { + this->var = var; + this->whole_structure_access = 0; + this->declaration = false; + this->components = NULL; + this->mem_ctx = NULL; + } + + ir_variable *var; /* The key: the variable's pointer. */ + + /** Number of times the variable is referenced, including assignments. */ + unsigned whole_structure_access; + + bool declaration; /* If the variable had a decl in the instruction stream */ + + ir_variable **components; + + /** talloc_parent(this->var) -- the shader's talloc context. */ + void *mem_ctx; +}; + + +class ir_structure_reference_visitor : public ir_hierarchical_visitor { +public: + ir_structure_reference_visitor(void) + { + this->mem_ctx = talloc_new(NULL); + this->variable_list.make_empty(); + } + + ~ir_structure_reference_visitor(void) + { + talloc_free(mem_ctx); + } + + virtual ir_visitor_status visit(ir_variable *); + virtual ir_visitor_status visit(ir_dereference_variable *); + virtual ir_visitor_status visit_enter(ir_dereference_record *); + virtual ir_visitor_status visit_enter(ir_assignment *); + virtual ir_visitor_status visit_enter(ir_function_signature *); + + variable_entry2 *get_variable_entry2(ir_variable *var); + + /* List of variable_entry */ + exec_list variable_list; + + void *mem_ctx; +}; + +variable_entry2 * +ir_structure_reference_visitor::get_variable_entry2(ir_variable *var) +{ + assert(var); + + if (!var->type->is_record() || var->mode == ir_var_uniform) + return NULL; + + foreach_iter(exec_list_iterator, iter, this->variable_list) { + variable_entry2 *entry = (variable_entry2 *)iter.get(); + if (entry->var == var) + return entry; + } + + variable_entry2 *entry = new(mem_ctx) variable_entry2(var); + this->variable_list.push_tail(entry); + return entry; +} + + +ir_visitor_status +ir_structure_reference_visitor::visit(ir_variable *ir) +{ + variable_entry2 *entry = this->get_variable_entry2(ir); + + if (entry) + entry->declaration = true; + + return visit_continue; +} + +ir_visitor_status +ir_structure_reference_visitor::visit(ir_dereference_variable *ir) +{ + ir_variable *const var = ir->variable_referenced(); + variable_entry2 *entry = this->get_variable_entry2(var); + + if (entry) + entry->whole_structure_access++; + + return visit_continue; +} + +ir_visitor_status +ir_structure_reference_visitor::visit_enter(ir_dereference_record *ir) +{ + (void) ir; + /* Don't descend into the ir_dereference_variable below. */ + return visit_continue_with_parent; +} + +ir_visitor_status +ir_structure_reference_visitor::visit_enter(ir_assignment *ir) +{ + if (ir->lhs->as_dereference_variable() && + ir->rhs->as_dereference_variable() && + !ir->condition) { + /* We'll split copies of a structure to copies of components, so don't + * descend to the ir_dereference_variables. + */ + return visit_continue_with_parent; + } + return visit_continue; +} + +ir_visitor_status +ir_structure_reference_visitor::visit_enter(ir_function_signature *ir) +{ + /* We don't want to descend into the function parameters and + * dead-code eliminate them, so just accept the body here. + */ + visit_list_elements(this, &ir->body); + return visit_continue_with_parent; +} + +class ir_structure_splitting_visitor : public ir_rvalue_visitor { +public: + ir_structure_splitting_visitor(exec_list *vars) + { + this->variable_list = vars; + } + + virtual ~ir_structure_splitting_visitor() + { + } + + virtual ir_visitor_status visit_leave(ir_assignment *); + + void split_deref(ir_dereference **deref); + void handle_rvalue(ir_rvalue **rvalue); + variable_entry2 *get_splitting_entry(ir_variable *var); + + exec_list *variable_list; + void *mem_ctx; +}; + +variable_entry2 * +ir_structure_splitting_visitor::get_splitting_entry(ir_variable *var) +{ + assert(var); + + if (!var->type->is_record()) + return NULL; + + foreach_iter(exec_list_iterator, iter, *this->variable_list) { + variable_entry2 *entry = (variable_entry2 *)iter.get(); + if (entry->var == var) { + return entry; + } + } + + return NULL; +} + +void +ir_structure_splitting_visitor::split_deref(ir_dereference **deref) +{ + if ((*deref)->ir_type != ir_type_dereference_record) + return; + + ir_dereference_record *deref_record = (ir_dereference_record *)*deref; + ir_dereference_variable *deref_var = deref_record->record->as_dereference_variable(); + if (!deref_var) + return; + + variable_entry2 *entry = get_splitting_entry(deref_var->var); + if (!entry) + return; + + unsigned int i; + for (i = 0; i < entry->var->type->length; i++) { + if (strcmp(deref_record->field, + entry->var->type->fields.structure[i].name) == 0) + break; + } + assert(i != entry->var->type->length); + + *deref = new(entry->mem_ctx) ir_dereference_variable(entry->components[i]); +} + +void +ir_structure_splitting_visitor::handle_rvalue(ir_rvalue **rvalue) +{ + if (!*rvalue) + return; + + ir_dereference *deref = (*rvalue)->as_dereference(); + + if (!deref) + return; + + split_deref(&deref); + *rvalue = deref; +} + +ir_visitor_status +ir_structure_splitting_visitor::visit_leave(ir_assignment *ir) +{ + ir_dereference_variable *lhs_deref = ir->lhs->as_dereference_variable(); + ir_dereference_variable *rhs_deref = ir->rhs->as_dereference_variable(); + variable_entry2 *lhs_entry = lhs_deref ? get_splitting_entry(lhs_deref->var) : NULL; + variable_entry2 *rhs_entry = rhs_deref ? get_splitting_entry(rhs_deref->var) : NULL; + const glsl_type *type = ir->rhs->type; + + if ((lhs_entry || rhs_entry) && !ir->condition) { + for (unsigned int i = 0; i < type->length; i++) { + ir_dereference *new_lhs, *new_rhs; + void *mem_ctx = lhs_entry ? lhs_entry->mem_ctx : rhs_entry->mem_ctx; + + if (lhs_entry) { + new_lhs = new(mem_ctx) ir_dereference_variable(lhs_entry->components[i]); + } else { + new_lhs = new(mem_ctx) + ir_dereference_record(ir->lhs->clone(mem_ctx, NULL), + type->fields.structure[i].name); + } + + if (rhs_entry) { + new_rhs = new(mem_ctx) ir_dereference_variable(rhs_entry->components[i]); + } else { + new_rhs = new(mem_ctx) + ir_dereference_record(ir->rhs->clone(mem_ctx, NULL), + type->fields.structure[i].name); + } + + ir->insert_before(new(mem_ctx) ir_assignment(new_lhs, + new_rhs, + NULL)); + } + ir->remove(); + } else { + handle_rvalue(&ir->rhs); + split_deref(&ir->lhs); + } + + handle_rvalue(&ir->condition); + + return visit_continue; +} + +bool +do_structure_splitting(exec_list *instructions) +{ + ir_structure_reference_visitor refs; + + visit_list_elements(&refs, instructions); + + /* Trim out variables we can't split. */ + foreach_iter(exec_list_iterator, iter, refs.variable_list) { + variable_entry2 *entry = (variable_entry2 *)iter.get(); + + if (debug) { + printf("structure %s@%p: decl %d, whole_access %d\n", + entry->var->name, (void *) entry->var, entry->declaration, + entry->whole_structure_access); + } + + if (!entry->declaration || entry->whole_structure_access) { + entry->remove(); + } + } + + if (refs.variable_list.is_empty()) + return false; + + void *mem_ctx = talloc_new(NULL); + + /* Replace the decls of the structures to be split with their split + * components. + */ + foreach_iter(exec_list_iterator, iter, refs.variable_list) { + variable_entry2 *entry = (variable_entry2 *)iter.get(); + const struct glsl_type *type = entry->var->type; + + entry->mem_ctx = talloc_parent(entry->var); + + entry->components = talloc_array(mem_ctx, + ir_variable *, + type->length); + + for (unsigned int i = 0; i < entry->var->type->length; i++) { + const char *name = talloc_asprintf(mem_ctx, "%s_%s", + entry->var->name, + type->fields.structure[i].name); + + entry->components[i] = + new(entry->mem_ctx) ir_variable(type->fields.structure[i].type, + name, + ir_var_temporary); + entry->var->insert_before(entry->components[i]); + } + + entry->var->remove(); + } + + ir_structure_splitting_visitor split(&refs.variable_list); + visit_list_elements(&split, instructions); + + talloc_free(mem_ctx); + + return true; +} |