src/glsl/ir_variable_refcount.h

   1 /*
   2  * Copyright © 2010 Intel Corporation
   3  *
   4  * Permission is hereby granted, free of charge, to any person obtaining a
   5  * copy of this software and associated documentation files (the "Software"),
   6  * to deal in the Software without restriction, including without limitation
   7  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
   8  * and/or sell copies of the Software, and to permit persons to whom the
   9  * Software is furnished to do so, subject to the following conditions:
  10  *
  11  * The above copyright notice and this permission notice (including the next
  12  * paragraph) shall be included in all copies or substantial portions of the
  13  * Software.
  14  *
  15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  16  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  17  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  18  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  19  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  20  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
  21  * DEALINGS IN THE SOFTWARE.
  22  */
  23
  24 /**
  25  * \file ir_variable_refcount.h
  26  *
  27  * Provides a visitor which produces a list of variables referenced,
  28  * how many times they were referenced and assigned, and whether they
  29  * were defined in the scope.
  30  */
  31
  32 #include "ir.h"
  33 #include "ir_visitor.h"
  34 #include "compiler/glsl_types.h"
  35
  36 struct assignment_entry {
  37    exec_node link;
  38    ir_assignment *assign;
  39 };
  40
  41 class ir_variable_refcount_entry
  42 {
  43 public:
  44    ir_variable_refcount_entry(ir_variable *var);
  45
  46    ir_variable *var; /* The key: the variable's pointer. */
  47
  48    /**
  49     * List of assignments to the variable, if any.
  50     * This is intended to be used for dead code optimisation and may
  51     * not be a complete list.
  52     */
  53    exec_list assign_list;
  54
  55    /** Number of times the variable is referenced, including assignments. */
  56    unsigned referenced_count;
  57
  58    /** Number of times the variable is assigned. */
  59    unsigned assigned_count;
  60
  61    bool declaration; /* If the variable had a decl in the instruction stream */
  62 };
  63
  64 class ir_variable_refcount_visitor : public ir_hierarchical_visitor {
  65 public:
  66    ir_variable_refcount_visitor(void);
  67    ~ir_variable_refcount_visitor(void);
  68
  69    virtual ir_visitor_status visit(ir_variable *);
  70    virtual ir_visitor_status visit(ir_dereference_variable *);
  71
  72    virtual ir_visitor_status visit_enter(ir_function_signature *);
  73    virtual ir_visitor_status visit_leave(ir_assignment *);
  74
  75    ir_variable_refcount_entry *get_variable_entry(ir_variable *var);
  76
  77    struct hash_table *ht;
  78
  79    void *mem_ctx;
  80 };