src/glsl/ir_hv_accept.cpp

/*
 * 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.
 */

#include "ir.h"

/**
 * \file ir_hv_accept.cpp
 * Implementations of all hierarchical visitor accept methods for IR
 * instructions.
 */

/**
 * Process a list of nodes using a hierarchical vistor.
 *
 * If statement_list is true (the default), this is a list of statements, so
 * v->base_ir will be set to point to each statement just before iterating
 * over it, and restored after iteration is complete.  If statement_list is
 * false, this is a list that appears inside a statement (e.g. a parameter
 * list), so v->base_ir will be left alone.
 *
 * \warning
 * This function will operate correctly if a node being processed is removed
 * from the list.  However, if nodes are added to the list after the node being
 * processed, some of the added nodes may not be processed.
 */
ir_visitor_status
visit_list_elements(ir_hierarchical_visitor *v, exec_list *l,
                    bool statement_list)
{
   ir_instruction *prev_base_ir = v->base_ir;

   foreach_list_safe(n, l) {
      ir_instruction *const ir = (ir_instruction *) n;
      if (statement_list)
         v->base_ir = ir;
      ir_visitor_status s = ir->accept(v);

      if (s != visit_continue)
	 return s;
   }
   if (statement_list)
      v->base_ir = prev_base_ir;

   return visit_continue;
}


ir_visitor_status
ir_rvalue::accept(ir_hierarchical_visitor *v)
{
   return v->visit(this);
}


ir_visitor_status
ir_variable::accept(ir_hierarchical_visitor *v)
{
   return v->visit(this);
}


ir_visitor_status
ir_loop::accept(ir_hierarchical_visitor *v)
{
   ir_visitor_status s = v->visit_enter(this);

   if (s != visit_continue)
      return (s == visit_continue_with_parent) ? visit_continue : s;

   s = visit_list_elements(v, &this->body_instructions);
   if (s == visit_stop)
      return s;

   if (s != visit_continue_with_parent) {
      if (this->from) {
	 s = this->from->accept(v);
	 if (s != visit_continue)
	    return (s == visit_continue_with_parent) ? visit_continue : s;
      }

      if (this->to) {
	 s = this->to->accept(v);
	 if (s != visit_continue)
	    return (s == visit_continue_with_parent) ? visit_continue : s;
      }

      if (this->increment) {
	 s = this->increment->accept(v);
	 if (s != visit_continue)
	    return (s == visit_continue_with_parent) ? visit_continue : s;
      }
   }

   return v->visit_leave(this);
}


ir_visitor_status
ir_loop_jump::accept(ir_hierarchical_visitor *v)
{
   return v->visit(this);
}


ir_visitor_status
ir_function_signature::accept(ir_hierarchical_visitor *v)
{
   ir_visitor_status s = v->visit_enter(this);
   if (s != visit_continue)
      return (s == visit_continue_with_parent) ? visit_continue : s;

   s = visit_list_elements(v, &this->parameters);
   if (s == visit_stop)
      return s;

   s = visit_list_elements(v, &this->body);
   return (s == visit_stop) ? s : v->visit_leave(this);
}


ir_visitor_status
ir_function::accept(ir_hierarchical_visitor *v)
{
   ir_visitor_status s = v->visit_enter(this);
   if (s != visit_continue)
      return (s == visit_continue_with_parent) ? visit_continue : s;

   s = visit_list_elements(v, &this->signatures, false);
   return (s == visit_stop) ? s : v->visit_leave(this);
}


ir_visitor_status
ir_expression::accept(ir_hierarchical_visitor *v)
{
   ir_visitor_status s = v->visit_enter(this);

   if (s != visit_continue)
      return (s == visit_continue_with_parent) ? visit_continue : s;

   for (unsigned i = 0; i < this->get_num_operands(); i++) {
      switch (this->operands[i]->accept(v)) {
      case visit_continue:
	 break;

      case visit_continue_with_parent:
	 // I wish for Java's labeled break-statement here.
	 goto done;

      case visit_stop:
	 return s;
      }
   }

done:
   return v->visit_leave(this);
}

ir_visitor_status
ir_texture::accept(ir_hierarchical_visitor *v)
{
   ir_visitor_status s = v->visit_enter(this);
   if (s != visit_continue)
      return (s == visit_continue_with_parent) ? visit_continue : s;

   s = this->sampler->accept(v);
   if (s != visit_continue)
      return (s == visit_continue_with_parent) ? visit_continue : s;

   if (this->coordinate) {
      s = this->coordinate->accept(v);
      if (s != visit_continue)
	 return (s == visit_continue_with_parent) ? visit_continue : s;
   }

   if (this->projector) {
      s = this->projector->accept(v);
      if (s != visit_continue)
	 return (s == visit_continue_with_parent) ? visit_continue : s;
   }

   if (this->shadow_comparitor) {
      s = this->shadow_comparitor->accept(v);
      if (s != visit_continue)
	 return (s == visit_continue_with_parent) ? visit_continue : s;
   }

   if (this->offset) {
      s = this->offset->accept(v);
      if (s != visit_continue)
	 return (s == visit_continue_with_parent) ? visit_continue : s;
   }

   switch (this->op) {
   case ir_tex:
      break;
   case ir_txb:
      s = this->lod_info.bias->accept(v);
      if (s != visit_continue)
	 return (s == visit_continue_with_parent) ? visit_continue : s;
      break;
   case ir_txl:
   case ir_txf:
   case ir_txs:
      s = this->lod_info.lod->accept(v);
      if (s != visit_continue)
	 return (s == visit_continue_with_parent) ? visit_continue : s;
      break;
   case ir_txd:
      s = this->lod_info.grad.dPdx->accept(v);
      if (s != visit_continue)
	 return (s == visit_continue_with_parent) ? visit_continue : s;

      s = this->lod_info.grad.dPdy->accept(v);
      if (s != visit_continue)
	 return (s == visit_continue_with_parent) ? visit_continue : s;
      break;
   }

   return (s == visit_stop) ? s : v->visit_leave(this);
}


ir_visitor_status
ir_swizzle::accept(ir_hierarchical_visitor *v)
{
   ir_visitor_status s = v->visit_enter(this);
   if (s != visit_continue)
      return (s == visit_continue_with_parent) ? visit_continue : s;

   s = this->val->accept(v);
   return (s == visit_stop) ? s : v->visit_leave(this);
}


ir_visitor_status
ir_dereference_variable::accept(ir_hierarchical_visitor *v)
{
   return v->visit(this);
}


ir_visitor_status
ir_dereference_array::accept(ir_hierarchical_visitor *v)
{
   ir_visitor_status s = v->visit_enter(this);
   if (s != visit_continue)
      return (s == visit_continue_with_parent) ? visit_continue : s;

   /* The array index is not the target of the assignment, so clear the
    * 'in_assignee' flag.  Restore it after returning from the array index.
    */
   const bool was_in_assignee = v->in_assignee;
   v->in_assignee = false;
   s = this->array_index->accept(v);
   v->in_assignee = was_in_assignee;

   if (s != visit_continue)
      return (s == visit_continue_with_parent) ? visit_continue : s;

   s = this->array->accept(v);
   return (s == visit_stop) ? s : v->visit_leave(this);
}


ir_visitor_status
ir_dereference_record::accept(ir_hierarchical_visitor *v)
{
   ir_visitor_status s = v->visit_enter(this);
   if (s != visit_continue)
      return (s == visit_continue_with_parent) ? visit_continue : s;

   s = this->record->accept(v);
   return (s == visit_stop) ? s : v->visit_leave(this);
}


ir_visitor_status
ir_assignment::accept(ir_hierarchical_visitor *v)
{
   ir_visitor_status s = v->visit_enter(this);
   if (s != visit_continue)
      return (s == visit_continue_with_parent) ? visit_continue : s;

   v->in_assignee = true;
   s = this->lhs->accept(v);
   v->in_assignee = false;
   if (s != visit_continue)
      return (s == visit_continue_with_parent) ? visit_continue : s;

   s = this->rhs->accept(v);
   if (s != visit_continue)
      return (s == visit_continue_with_parent) ? visit_continue : s;

   if (this->condition)
      s = this->condition->accept(v);

   return (s == visit_stop) ? s : v->visit_leave(this);
}


ir_visitor_status
ir_constant::accept(ir_hierarchical_visitor *v)
{
   return v->visit(this);
}


ir_visitor_status
ir_call::accept(ir_hierarchical_visitor *v)
{
   ir_visitor_status s = v->visit_enter(this);
   if (s != visit_continue)
      return (s == visit_continue_with_parent) ? visit_continue : s;

   if (this->return_deref != NULL) {
      v->in_assignee = true;
      s = this->return_deref->accept(v);
      v->in_assignee = false;
      if (s != visit_continue)
	 return (s == visit_continue_with_parent) ? visit_continue : s;
   }

   s = visit_list_elements(v, &this->actual_parameters, false);
   if (s == visit_stop)
      return s;

   return v->visit_leave(this);
}


ir_visitor_status
ir_return::accept(ir_hierarchical_visitor *v)
{
   ir_visitor_status s = v->visit_enter(this);
   if (s != visit_continue)
      return (s == visit_continue_with_parent) ? visit_continue : s;

   ir_rvalue *val = this->get_value();
   if (val) {
      s = val->accept(v);
      if (s != visit_continue)
	 return (s == visit_continue_with_parent) ? visit_continue : s;
   }

   return v->visit_leave(this);
}


ir_visitor_status
ir_discard::accept(ir_hierarchical_visitor *v)
{
   ir_visitor_status s = v->visit_enter(this);
   if (s != visit_continue)
      return (s == visit_continue_with_parent) ? visit_continue : s;

   if (this->condition != NULL) {
      s = this->condition->accept(v);
      if (s != visit_continue)
	 return (s == visit_continue_with_parent) ? visit_continue : s;
   }

   return v->visit_leave(this);
}


ir_visitor_status
ir_if::accept(ir_hierarchical_visitor *v)
{
   ir_visitor_status s = v->visit_enter(this);
   if (s != visit_continue)
      return (s == visit_continue_with_parent) ? visit_continue : s;

   s = this->condition->accept(v);
   if (s != visit_continue)
      return (s == visit_continue_with_parent) ? visit_continue : s;

   if (s != visit_continue_with_parent) {
      s = visit_list_elements(v, &this->then_instructions);
      if (s == visit_stop)
	 return s;
   }

   if (s != visit_continue_with_parent) {
      s = visit_list_elements(v, &this->else_instructions);
      if (s == visit_stop)
	 return s;
   }

   return v->visit_leave(this);
}