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-rw-r--r--mesalib/src/glsl/ir_structure_splitting.cpp361
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diff --git a/mesalib/src/glsl/ir_structure_splitting.cpp b/mesalib/src/glsl/ir_structure_splitting.cpp
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+/*
+ * 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;
+}