glsl2: Move the compiler to the subdirectory it will live in in Mesa.

1 files changed, 818 insertions, 0 deletions

diff --git a/src/glsl/ir.cpp b/src/glsl/ir.cpp
new file mode 100644
index 00000000000..2756752ba49
--- /dev/null
+++ b/src/glsl/ir.cpp
@@ -0,0 +1,818 @@
+/*
+ * 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 <string.h>
+#include "main/imports.h"
+#include "ir.h"
+#include "ir_visitor.h"
+#include "glsl_types.h"
+
+ir_assignment::ir_assignment(ir_rvalue *lhs, ir_rvalue *rhs,
+			     ir_rvalue *condition)
+{
+   this->lhs = lhs;
+   this->rhs = rhs;
+   this->condition = condition;
+}
+
+
+ir_expression::ir_expression(int op, const struct glsl_type *type,
+			     ir_rvalue *op0, ir_rvalue *op1)
+{
+   this->type = type;
+   this->operation = ir_expression_operation(op);
+   this->operands[0] = op0;
+   this->operands[1] = op1;
+}
+
+unsigned int
+ir_expression::get_num_operands(ir_expression_operation op)
+{
+/* Update ir_print_visitor.cpp when updating this list. */
+   const int num_operands[] = {
+      1, /* ir_unop_bit_not */
+      1, /* ir_unop_logic_not */
+      1, /* ir_unop_neg */
+      1, /* ir_unop_abs */
+      1, /* ir_unop_sign */
+      1, /* ir_unop_rcp */
+      1, /* ir_unop_rsq */
+      1, /* ir_unop_sqrt */
+      1, /* ir_unop_exp */
+      1, /* ir_unop_log */
+      1, /* ir_unop_exp2 */
+      1, /* ir_unop_log2 */
+      1, /* ir_unop_f2i */
+      1, /* ir_unop_i2f */
+      1, /* ir_unop_f2b */
+      1, /* ir_unop_b2f */
+      1, /* ir_unop_i2b */
+      1, /* ir_unop_b2i */
+      1, /* ir_unop_u2f */
+
+      1, /* ir_unop_trunc */
+      1, /* ir_unop_ceil */
+      1, /* ir_unop_floor */
+
+      1, /* ir_unop_sin */
+      1, /* ir_unop_cos */
+
+      1, /* ir_unop_dFdx */
+      1, /* ir_unop_dFdy */
+
+      2, /* ir_binop_add */
+      2, /* ir_binop_sub */
+      2, /* ir_binop_mul */
+      2, /* ir_binop_div */
+      2, /* ir_binop_mod */
+
+      2, /* ir_binop_less */
+      2, /* ir_binop_greater */
+      2, /* ir_binop_lequal */
+      2, /* ir_binop_gequal */
+      2, /* ir_binop_equal */
+      2, /* ir_binop_nequal */
+
+      2, /* ir_binop_lshift */
+      2, /* ir_binop_rshift */
+      2, /* ir_binop_bit_and */
+      2, /* ir_binop_bit_xor */
+      2, /* ir_binop_bit_or */
+
+      2, /* ir_binop_logic_and */
+      2, /* ir_binop_logic_xor */
+      2, /* ir_binop_logic_or */
+
+      2, /* ir_binop_dot */
+      2, /* ir_binop_min */
+      2, /* ir_binop_max */
+
+      2, /* ir_binop_pow */
+   };
+
+   assert(sizeof(num_operands) / sizeof(num_operands[0]) == ir_binop_pow + 1);
+
+   return num_operands[op];
+}
+
+static const char *const operator_strs[] = {
+   "~",
+   "!",
+   "neg",
+   "abs",
+   "sign",
+   "rcp",
+   "rsq",
+   "sqrt",
+   "exp",
+   "log",
+   "exp2",
+   "log2",
+   "f2i",
+   "i2f",
+   "f2b",
+   "b2f",
+   "i2b",
+   "b2i",
+   "u2f",
+   "trunc",
+   "ceil",
+   "floor",
+   "sin",
+   "cos",
+   "dFdx",
+   "dFdy",
+   "+",
+   "-",
+   "*",
+   "/",
+   "%",
+   "<",
+   ">",
+   "<=",
+   ">=",
+   "==",
+   "!=",
+   "<<",
+   ">>",
+   "&",
+   "^",
+   "|",
+   "&&",
+   "^^",
+   "||",
+   "dot",
+   "min",
+   "max",
+   "pow",
+};
+
+const char *ir_expression::operator_string()
+{
+   assert((unsigned int) operation <=
+	  sizeof(operator_strs) / sizeof(operator_strs[0]));
+   return operator_strs[operation];
+}
+
+ir_expression_operation
+ir_expression::get_operator(const char *str)
+{
+   const int operator_count = sizeof(operator_strs) / sizeof(operator_strs[0]);
+   for (int op = 0; op < operator_count; op++) {
+      if (strcmp(str, operator_strs[op]) == 0)
+	 return (ir_expression_operation) op;
+   }
+   return (ir_expression_operation) -1;
+}
+
+ir_constant::ir_constant()
+{
+   /* empty */
+}
+
+ir_constant::ir_constant(const struct glsl_type *type,
+			 const ir_constant_data *data)
+{
+   assert((type->base_type >= GLSL_TYPE_UINT)
+	  && (type->base_type <= GLSL_TYPE_BOOL));
+
+   this->type = type;
+   memcpy(& this->value, data, sizeof(this->value));
+}
+
+ir_constant::ir_constant(float f)
+{
+   this->type = glsl_type::float_type;
+   this->value.f[0] = f;
+}
+
+ir_constant::ir_constant(unsigned int u)
+{
+   this->type = glsl_type::uint_type;
+   this->value.u[0] = u;
+}
+
+ir_constant::ir_constant(int i)
+{
+   this->type = glsl_type::int_type;
+   this->value.i[0] = i;
+}
+
+ir_constant::ir_constant(bool b)
+{
+   this->type = glsl_type::bool_type;
+   this->value.b[0] = b;
+}
+
+ir_constant::ir_constant(const ir_constant *c, unsigned i)
+{
+   this->type = c->type->get_base_type();
+
+   switch (this->type->base_type) {
+   case GLSL_TYPE_UINT:  this->value.u[0] = c->value.u[i]; break;
+   case GLSL_TYPE_INT:   this->value.i[0] = c->value.i[i]; break;
+   case GLSL_TYPE_FLOAT: this->value.f[0] = c->value.f[i]; break;
+   case GLSL_TYPE_BOOL:  this->value.b[0] = c->value.b[i]; break;
+   default:              assert(!"Should not get here."); break;
+   }
+}
+
+ir_constant::ir_constant(const struct glsl_type *type, exec_list *value_list)
+{
+   this->type = type;
+
+   /* FINISHME: Support array types. */
+   assert(type->is_scalar() || type->is_vector() || type->is_matrix()
+	  || type->is_record());
+
+   /* If the constant is a record, the types of each of the entries in
+    * value_list must be a 1-for-1 match with the structure components.  Each
+    * entry must also be a constant.  Just move the nodes from the value_list
+    * to the list in the ir_constant.
+    */
+   /* FINISHME: Should there be some type checking and / or assertions here? */
+   /* FINISHME: Should the new constant take ownership of the nodes from
+    * FINISHME: value_list, or should it make copies?
+    */
+   if (type->is_record()) {
+      value_list->move_nodes_to(& this->components);
+      return;
+   }
+
+
+   ir_constant *value = (ir_constant *) (value_list->head);
+
+   /* Use each component from each entry in the value_list to initialize one
+    * component of the constant being constructed.
+    */
+   for (unsigned i = 0; i < type->components(); /* empty */) {
+      assert(value->as_constant() != NULL);
+      assert(!value->is_tail_sentinal());
+
+      for (unsigned j = 0; j < value->type->components(); j++) {
+	 switch (type->base_type) {
+	 case GLSL_TYPE_UINT:
+	    this->value.u[i] = value->get_uint_component(j);
+	    break;
+	 case GLSL_TYPE_INT:
+	    this->value.i[i] = value->get_int_component(j);
+	    break;
+	 case GLSL_TYPE_FLOAT:
+	    this->value.f[i] = value->get_float_component(j);
+	    break;
+	 case GLSL_TYPE_BOOL:
+	    this->value.b[i] = value->get_bool_component(j);
+	    break;
+	 default:
+	    /* FINISHME: What to do?  Exceptions are not the answer.
+	     */
+	    break;
+	 }
+
+	 i++;
+	 if (i >= type->components())
+	    break;
+      }
+
+      value = (ir_constant *) value->next;
+   }
+}
+
+bool
+ir_constant::get_bool_component(unsigned i) const
+{
+   switch (this->type->base_type) {
+   case GLSL_TYPE_UINT:  return this->value.u[i] != 0;
+   case GLSL_TYPE_INT:   return this->value.i[i] != 0;
+   case GLSL_TYPE_FLOAT: return ((int)this->value.f[i]) != 0;
+   case GLSL_TYPE_BOOL:  return this->value.b[i];
+   default:              assert(!"Should not get here."); break;
+   }
+
+   /* Must return something to make the compiler happy.  This is clearly an
+    * error case.
+    */
+   return false;
+}
+
+float
+ir_constant::get_float_component(unsigned i) const
+{
+   switch (this->type->base_type) {
+   case GLSL_TYPE_UINT:  return (float) this->value.u[i];
+   case GLSL_TYPE_INT:   return (float) this->value.i[i];
+   case GLSL_TYPE_FLOAT: return this->value.f[i];
+   case GLSL_TYPE_BOOL:  return this->value.b[i] ? 1.0 : 0.0;
+   default:              assert(!"Should not get here."); break;
+   }
+
+   /* Must return something to make the compiler happy.  This is clearly an
+    * error case.
+    */
+   return 0.0;
+}
+
+int
+ir_constant::get_int_component(unsigned i) const
+{
+   switch (this->type->base_type) {
+   case GLSL_TYPE_UINT:  return this->value.u[i];
+   case GLSL_TYPE_INT:   return this->value.i[i];
+   case GLSL_TYPE_FLOAT: return (int) this->value.f[i];
+   case GLSL_TYPE_BOOL:  return this->value.b[i] ? 1 : 0;
+   default:              assert(!"Should not get here."); break;
+   }
+
+   /* Must return something to make the compiler happy.  This is clearly an
+    * error case.
+    */
+   return 0;
+}
+
+unsigned
+ir_constant::get_uint_component(unsigned i) const
+{
+   switch (this->type->base_type) {
+   case GLSL_TYPE_UINT:  return this->value.u[i];
+   case GLSL_TYPE_INT:   return this->value.i[i];
+   case GLSL_TYPE_FLOAT: return (unsigned) this->value.f[i];
+   case GLSL_TYPE_BOOL:  return this->value.b[i] ? 1 : 0;
+   default:              assert(!"Should not get here."); break;
+   }
+
+   /* Must return something to make the compiler happy.  This is clearly an
+    * error case.
+    */
+   return 0;
+}
+
+
+ir_constant *
+ir_constant::get_record_field(const char *name)
+{
+   int idx = this->type->field_index(name);
+
+   if (idx < 0)
+      return NULL;
+
+   if (this->components.is_empty())
+      return NULL;
+
+   exec_node *node = this->components.head;
+   for (int i = 0; i < idx; i++) {
+      node = node->next;
+
+      /* If the end of the list is encountered before the element matching the
+       * requested field is found, return NULL.
+       */
+      if (node->is_tail_sentinal())
+	 return NULL;
+   }
+
+   return (ir_constant *) node;
+}
+
+
+bool
+ir_constant::has_value(const ir_constant *c) const
+{
+   if (this->type != c->type)
+      return false;
+
+   /* FINISHME: This will probably also handle constant arrays as soon as those
+    * FINISHME: are supported.
+    */
+   if (this->type->base_type == GLSL_TYPE_STRUCT) {
+      const exec_node *a_node = this->components.head;
+      const exec_node *b_node = c->components.head;
+
+      while (!a_node->is_tail_sentinal()) {
+	 assert(!b_node->is_tail_sentinal());
+
+	 const ir_constant *const a_field = (ir_constant *) a_node;
+	 const ir_constant *const b_field = (ir_constant *) b_node;
+
+	 if (!a_field->has_value(b_field))
+	    return false;
+
+	 a_node = a_node->next;
+	 b_node = b_node->next;
+      }
+
+      return true;
+   }
+
+   for (unsigned i = 0; i < this->type->components(); i++) {
+      switch (this->type->base_type) {
+      case GLSL_TYPE_UINT:
+	 if (this->value.u[i] != c->value.u[i])
+	    return false;
+	 break;
+      case GLSL_TYPE_INT:
+	 if (this->value.i[i] != c->value.i[i])
+	    return false;
+	 break;
+      case GLSL_TYPE_FLOAT:
+	 if (this->value.f[i] != c->value.f[i])
+	    return false;
+	 break;
+      case GLSL_TYPE_BOOL:
+	 if (this->value.b[i] != c->value.b[i])
+	    return false;
+	 break;
+      default:
+	 assert(!"Should not get here.");
+	 return false;
+      }
+   }
+
+   return true;
+}
+
+ir_dereference_variable::ir_dereference_variable(ir_variable *var)
+{
+   this->var = var;
+   this->type = (var != NULL) ? var->type : glsl_type::error_type;
+}
+
+
+ir_dereference_array::ir_dereference_array(ir_rvalue *value,
+					   ir_rvalue *array_index)
+{
+   this->array_index = array_index;
+   this->set_array(value);
+}
+
+
+ir_dereference_array::ir_dereference_array(ir_variable *var,
+					   ir_rvalue *array_index)
+{
+   void *ctx = talloc_parent(var);
+
+   this->array_index = array_index;
+   this->set_array(new(ctx) ir_dereference_variable(var));
+}
+
+
+void
+ir_dereference_array::set_array(ir_rvalue *value)
+{
+   this->array = value;
+   this->type = glsl_type::error_type;
+
+   if (this->array != NULL) {
+      const glsl_type *const vt = this->array->type;
+
+      if (vt->is_array()) {
+	 type = vt->element_type();
+      } else if (vt->is_matrix()) {
+	 type = vt->column_type();
+      } else if (vt->is_vector()) {
+	 type = vt->get_base_type();
+      }
+   }
+}
+
+
+ir_dereference_record::ir_dereference_record(ir_rvalue *value,
+					     const char *field)
+{
+   this->record = value;
+   this->field = field;
+   this->type = (this->record != NULL)
+      ? this->record->type->field_type(field) : glsl_type::error_type;
+}
+
+
+ir_dereference_record::ir_dereference_record(ir_variable *var,
+					     const char *field)
+{
+   void *ctx = talloc_parent(var);
+
+   this->record = new(ctx) ir_dereference_variable(var);
+   this->field = field;
+   this->type = (this->record != NULL)
+      ? this->record->type->field_type(field) : glsl_type::error_type;
+}
+
+
+bool
+ir_dereference::is_lvalue()
+{
+   ir_variable *var = this->variable_referenced();
+
+   /* Every l-value derference chain eventually ends in a variable.
+    */
+   if ((var == NULL) || var->read_only)
+      return false;
+
+   if (this->type->is_array() && !var->array_lvalue)
+      return false;
+
+   return true;
+}
+
+
+const char *tex_opcode_strs[] = { "tex", "txb", "txl", "txd", "txf" };
+
+const char *ir_texture::opcode_string()
+{
+   assert((unsigned int) op <=
+	  sizeof(tex_opcode_strs) / sizeof(tex_opcode_strs[0]));
+   return tex_opcode_strs[op];
+}
+
+ir_texture_opcode
+ir_texture::get_opcode(const char *str)
+{
+   const int count = sizeof(tex_opcode_strs) / sizeof(tex_opcode_strs[0]);
+   for (int op = 0; op < count; op++) {
+      if (strcmp(str, tex_opcode_strs[op]) == 0)
+	 return (ir_texture_opcode) op;
+   }
+   return (ir_texture_opcode) -1;
+}
+
+
+void
+ir_texture::set_sampler(ir_dereference *sampler)
+{
+   assert(sampler != NULL);
+   this->sampler = sampler;
+
+   switch (sampler->type->sampler_type) {
+   case GLSL_TYPE_FLOAT:
+      this->type = glsl_type::vec4_type;
+      break;
+   case GLSL_TYPE_INT:
+      this->type = glsl_type::ivec4_type;
+      break;
+   case GLSL_TYPE_UINT:
+      this->type = glsl_type::uvec4_type;
+      break;
+   }
+}
+
+
+ir_swizzle::ir_swizzle(ir_rvalue *val, unsigned x, unsigned y, unsigned z,
+		       unsigned w, unsigned count)
+   : val(val)
+{
+   assert((count >= 1) && (count <= 4));
+
+   const unsigned dup_mask = 0
+      | ((count > 1) ? ((1U << y) & ((1U << x)                        )) : 0)
+      | ((count > 2) ? ((1U << z) & ((1U << x) | (1U << y)            )) : 0)
+      | ((count > 3) ? ((1U << w) & ((1U << x) | (1U << y) | (1U << z))) : 0);
+
+   assert(x <= 3);
+   assert(y <= 3);
+   assert(z <= 3);
+   assert(w <= 3);
+
+   mask.x = x;
+   mask.y = y;
+   mask.z = z;
+   mask.w = w;
+   mask.num_components = count;
+   mask.has_duplicates = dup_mask != 0;
+
+   /* Based on the number of elements in the swizzle and the base type
+    * (i.e., float, int, unsigned, or bool) of the vector being swizzled,
+    * generate the type of the resulting value.
+    */
+   type = glsl_type::get_instance(val->type->base_type, mask.num_components, 1);
+}
+
+ir_swizzle::ir_swizzle(ir_rvalue *val, ir_swizzle_mask mask)
+{
+   this->val = val;
+   this->mask = mask;
+   this->type = glsl_type::get_instance(val->type->base_type,
+					mask.num_components, 1);
+}
+
+#define X 1
+#define R 5
+#define S 9
+#define I 13
+
+ir_swizzle *
+ir_swizzle::create(ir_rvalue *val, const char *str, unsigned vector_length)
+{
+   void *ctx = talloc_parent(val);
+
+   /* For each possible swizzle character, this table encodes the value in
+    * \c idx_map that represents the 0th element of the vector.  For invalid
+    * swizzle characters (e.g., 'k'), a special value is used that will allow
+    * detection of errors.
+    */
+   static const unsigned char base_idx[26] = {
+   /* a  b  c  d  e  f  g  h  i  j  k  l  m */
+      R, R, I, I, I, I, R, I, I, I, I, I, I,
+   /* n  o  p  q  r  s  t  u  v  w  x  y  z */
+      I, I, S, S, R, S, S, I, I, X, X, X, X
+   };
+
+   /* Each valid swizzle character has an entry in the previous table.  This
+    * table encodes the base index encoded in the previous table plus the actual
+    * index of the swizzle character.  When processing swizzles, the first
+    * character in the string is indexed in the previous table.  Each character
+    * in the string is indexed in this table, and the value found there has the
+    * value form the first table subtracted.  The result must be on the range
+    * [0,3].
+    *
+    * For example, the string "wzyx" will get X from the first table.  Each of
+    * the charcaters will get X+3, X+2, X+1, and X+0 from this table.  After
+    * subtraction, the swizzle values are { 3, 2, 1, 0 }.
+    *
+    * The string "wzrg" will get X from the first table.  Each of the characters
+    * will get X+3, X+2, R+0, and R+1 from this table.  After subtraction, the
+    * swizzle values are { 3, 2, 4, 5 }.  Since 4 and 5 are outside the range
+    * [0,3], the error is detected.
+    */
+   static const unsigned char idx_map[26] = {
+   /* a    b    c    d    e    f    g    h    i    j    k    l    m */
+      R+3, R+2, 0,   0,   0,   0,   R+1, 0,   0,   0,   0,   0,   0,
+   /* n    o    p    q    r    s    t    u    v    w    x    y    z */
+      0,   0,   S+2, S+3, R+0, S+0, S+1, 0,   0,   X+3, X+0, X+1, X+2
+   };
+
+   int swiz_idx[4] = { 0, 0, 0, 0 };
+   unsigned i;
+
+
+   /* Validate the first character in the swizzle string and look up the base
+    * index value as described above.
+    */
+   if ((str[0] < 'a') || (str[0] > 'z'))
+      return NULL;
+
+   const unsigned base = base_idx[str[0] - 'a'];
+
+
+   for (i = 0; (i < 4) && (str[i] != '\0'); i++) {
+      /* Validate the next character, and, as described above, convert it to a
+       * swizzle index.
+       */
+      if ((str[i] < 'a') || (str[i] > 'z'))
+	 return NULL;
+
+      swiz_idx[i] = idx_map[str[i] - 'a'] - base;
+      if ((swiz_idx[i] < 0) || (swiz_idx[i] >= (int) vector_length))
+	 return NULL;
+   }
+
+   if (str[i] != '\0')
+	 return NULL;
+
+   return new(ctx) ir_swizzle(val, swiz_idx[0], swiz_idx[1], swiz_idx[2],
+			      swiz_idx[3], i);
+}
+
+#undef X
+#undef R
+#undef S
+#undef I
+
+ir_variable *
+ir_swizzle::variable_referenced()
+{
+   return this->val->variable_referenced();
+}
+
+ir_variable::ir_variable(const struct glsl_type *type, const char *name)
+   : max_array_access(0), read_only(false), centroid(false), invariant(false),
+     shader_in(false), shader_out(false),
+     mode(ir_var_auto), interpolation(ir_var_smooth), array_lvalue(false)
+{
+   this->type = type;
+   this->name = name;
+   this->location = -1;
+   this->warn_extension = NULL;
+   this->constant_value = NULL;
+
+   if (type && type->base_type == GLSL_TYPE_SAMPLER)
+      this->read_only = true;
+}
+
+
+const char *
+ir_variable::interpolation_string() const
+{
+   if (!this->shader_in && !this->shader_out)
+      return "";
+
+   switch (this->interpolation) {
+   case ir_var_smooth:        return "smooth";
+   case ir_var_flat:          return "flat";
+   case ir_var_noperspective: return "noperspective";
+   }
+
+   assert(!"Should not get here.");
+   return "";
+}
+
+
+unsigned
+ir_variable::component_slots() const
+{
+   /* FINISHME: Sparsely accessed arrays require fewer slots. */
+   return this->type->component_slots();
+}
+
+
+ir_function_signature::ir_function_signature(const glsl_type *return_type)
+   : return_type(return_type), is_defined(false)
+{
+   /* empty */
+}
+
+
+const char *
+ir_function_signature::qualifiers_match(exec_list *params)
+{
+   exec_list_iterator iter_a = parameters.iterator();
+   exec_list_iterator iter_b = params->iterator();
+
+   /* check that the qualifiers match. */
+   while (iter_a.has_next()) {
+      ir_variable *a = (ir_variable *)iter_a.get();
+      ir_variable *b = (ir_variable *)iter_b.get();
+
+      if (a->read_only != b->read_only ||
+	  a->mode != b->mode ||
+	  a->interpolation != b->interpolation ||
+	  a->centroid != b->centroid) {
+
+	 /* parameter a's qualifiers don't match */
+	 return a->name;
+      }
+
+      iter_a.next();
+      iter_b.next();
+   }
+   return NULL;
+}
+
+
+void
+ir_function_signature::replace_parameters(exec_list *new_params)
+{
+   /* Destroy all of the previous parameter information.  If the previous
+    * parameter information comes from the function prototype, it may either
+    * specify incorrect parameter names or not have names at all.
+    */
+   foreach_iter(exec_list_iterator, iter, parameters) {
+      assert(((ir_instruction *) iter.get())->as_variable() != NULL);
+
+      iter.remove();
+   }
+
+   new_params->move_nodes_to(&parameters);
+}
+
+
+ir_function::ir_function(const char *name)
+   : name(name)
+{
+   /* empty */
+}
+
+
+ir_call *
+ir_call::get_error_instruction(void *ctx)
+{
+   ir_call *call = new(ctx) ir_call;
+
+   call->type = glsl_type::error_type;
+   return call;
+}
+
+void
+visit_exec_list(exec_list *list, ir_visitor *visitor)
+{
+   foreach_iter(exec_list_iterator, iter, *list) {
+      ((ir_instruction *)iter.get())->accept(visitor);
+   }
+}
+