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

1 files changed, 751 insertions, 0 deletions

diff --git a/src/glsl/ast_function.cpp b/src/glsl/ast_function.cpp
new file mode 100644
index 0000000000..761af00b95
--- /dev/null
+++ b/src/glsl/ast_function.cpp
@@ -0,0 +1,751 @@
+/*
+ * 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 "glsl_symbol_table.h"
+#include "ast.h"
+#include "glsl_types.h"
+#include "ir.h"
+
+static unsigned
+process_parameters(exec_list *instructions, exec_list *actual_parameters,
+		   exec_list *parameters,
+		   struct _mesa_glsl_parse_state *state)
+{
+   unsigned count = 0;
+
+   foreach_list (n, parameters) {
+      ast_node *const ast = exec_node_data(ast_node, n, link);
+      ir_rvalue *result = ast->hir(instructions, state);
+
+      ir_constant *const constant = result->constant_expression_value();
+      if (constant != NULL)
+	 result = constant;
+
+      actual_parameters->push_tail(result);
+      count++;
+   }
+
+   return count;
+}
+
+
+static ir_rvalue *
+process_call(exec_list *instructions, ir_function *f,
+	     YYLTYPE *loc, exec_list *actual_parameters,
+	     struct _mesa_glsl_parse_state *state)
+{
+   void *ctx = talloc_parent(state);
+
+   const ir_function_signature *sig =
+      f->matching_signature(actual_parameters);
+
+   /* The instructions param will be used when the FINISHMEs below are done */
+   (void) instructions;
+
+   if (sig != NULL) {
+      /* Verify that 'out' and 'inout' actual parameters are lvalues.  This
+       * isn't done in ir_function::matching_signature because that function
+       * cannot generate the necessary diagnostics.
+       */
+      exec_list_iterator actual_iter = actual_parameters->iterator();
+      exec_list_iterator formal_iter = sig->parameters.iterator();
+
+      while (actual_iter.has_next()) {
+	 ir_rvalue *actual = (ir_rvalue *) actual_iter.get();
+	 ir_variable *formal = (ir_variable *) formal_iter.get();
+
+	 assert(actual != NULL);
+	 assert(formal != NULL);
+
+	 if ((formal->mode == ir_var_out)
+	     || (formal->mode == ir_var_inout)) {
+	    if (! actual->is_lvalue()) {
+	       /* FINISHME: Log a better diagnostic here.  There is no way
+		* FINISHME: to tell the user which parameter is invalid.
+		*/
+	       _mesa_glsl_error(loc, state, "`%s' parameter is not lvalue",
+				(formal->mode == ir_var_out) ? "out" : "inout");
+	    }
+	 }
+
+	 actual_iter.next();
+	 formal_iter.next();
+      }
+
+      /* FINISHME: The list of actual parameters needs to be modified to
+       * FINISHME: include any necessary conversions.
+       */
+      return new(ctx) ir_call(sig, actual_parameters);
+   } else {
+      /* FINISHME: Log a better error message here.  G++ will show the types
+       * FINISHME: of the actual parameters and the set of candidate
+       * FINISHME: functions.  A different error should also be logged when
+       * FINISHME: multiple functions match.
+       */
+      _mesa_glsl_error(loc, state, "no matching function for call to `%s'",
+		       f->name);
+      return ir_call::get_error_instruction(ctx);
+   }
+}
+
+
+static ir_rvalue *
+match_function_by_name(exec_list *instructions, const char *name,
+		       YYLTYPE *loc, exec_list *actual_parameters,
+		       struct _mesa_glsl_parse_state *state)
+{
+   void *ctx = talloc_parent(state);
+   ir_function *f = state->symbols->get_function(name);
+
+   if (f == NULL) {
+      _mesa_glsl_error(loc, state, "function `%s' undeclared", name);
+      return ir_call::get_error_instruction(ctx);
+   }
+
+   /* Once we've determined that the function being called might exist, try
+    * to find an overload of the function that matches the parameters.
+    */
+   return process_call(instructions, f, loc, actual_parameters, state);
+}
+
+
+/**
+ * Perform automatic type conversion of constructor parameters
+ */
+static ir_rvalue *
+convert_component(ir_rvalue *src, const glsl_type *desired_type)
+{
+   void *ctx = talloc_parent(src);
+   const unsigned a = desired_type->base_type;
+   const unsigned b = src->type->base_type;
+   ir_expression *result = NULL;
+
+   if (src->type->is_error())
+      return src;
+
+   assert(a <= GLSL_TYPE_BOOL);
+   assert(b <= GLSL_TYPE_BOOL);
+
+   if ((a == b) || (src->type->is_integer() && desired_type->is_integer()))
+      return src;
+
+   switch (a) {
+   case GLSL_TYPE_UINT:
+   case GLSL_TYPE_INT:
+      if (b == GLSL_TYPE_FLOAT)
+	 result = new(ctx) ir_expression(ir_unop_f2i, desired_type, src, NULL);
+      else {
+	 assert(b == GLSL_TYPE_BOOL);
+	 result = new(ctx) ir_expression(ir_unop_b2i, desired_type, src, NULL);
+      }
+      break;
+   case GLSL_TYPE_FLOAT:
+      switch (b) {
+      case GLSL_TYPE_UINT:
+	 result = new(ctx) ir_expression(ir_unop_u2f, desired_type, src, NULL);
+	 break;
+      case GLSL_TYPE_INT:
+	 result = new(ctx) ir_expression(ir_unop_i2f, desired_type, src, NULL);
+	 break;
+      case GLSL_TYPE_BOOL:
+	 result = new(ctx) ir_expression(ir_unop_b2f, desired_type, src, NULL);
+	 break;
+      }
+      break;
+   case GLSL_TYPE_BOOL: {
+      ir_constant *zero = NULL;
+
+      switch (b) {
+      case GLSL_TYPE_UINT:  zero = new(ctx) ir_constant(unsigned(0)); break;
+      case GLSL_TYPE_INT:   zero = new(ctx) ir_constant(int(0));      break;
+      case GLSL_TYPE_FLOAT: zero = new(ctx) ir_constant(0.0f);        break;
+      }
+
+      result = new(ctx) ir_expression(ir_binop_nequal, desired_type, src, zero);
+   }
+   }
+
+   assert(result != NULL);
+
+   ir_constant *const constant = result->constant_expression_value();
+   return (constant != NULL) ? (ir_rvalue *) constant : (ir_rvalue *) result;
+}
+
+
+/**
+ * Dereference a specific component from a scalar, vector, or matrix
+ */
+static ir_rvalue *
+dereference_component(ir_rvalue *src, unsigned component)
+{
+   void *ctx = talloc_parent(src);
+   assert(component < src->type->components());
+
+   /* If the source is a constant, just create a new constant instead of a
+    * dereference of the existing constant.
+    */
+   ir_constant *constant = src->as_constant();
+   if (constant)
+      return new(ctx) ir_constant(constant, component);
+
+   if (src->type->is_scalar()) {
+      return src;
+   } else if (src->type->is_vector()) {
+      return new(ctx) ir_swizzle(src, component, 0, 0, 0, 1);
+   } else {
+      assert(src->type->is_matrix());
+
+      /* Dereference a row of the matrix, then call this function again to get
+       * a specific element from that row.
+       */
+      const int c = component / src->type->column_type()->vector_elements;
+      const int r = component % src->type->column_type()->vector_elements;
+      ir_constant *const col_index = new(ctx) ir_constant(c);
+      ir_dereference *const col = new(ctx) ir_dereference_array(src, col_index);
+
+      col->type = src->type->column_type();
+
+      return dereference_component(col, r);
+   }
+
+   assert(!"Should not get here.");
+   return NULL;
+}
+
+
+static ir_rvalue *
+process_array_constructor(exec_list *instructions,
+			  const glsl_type *constructor_type,
+			  YYLTYPE *loc, exec_list *parameters,
+			  struct _mesa_glsl_parse_state *state)
+{
+   void *ctx = talloc_parent(state);
+   /* Array constructors come in two forms: sized and unsized.  Sized array
+    * constructors look like 'vec4[2](a, b)', where 'a' and 'b' are vec4
+    * variables.  In this case the number of parameters must exactly match the
+    * specified size of the array.
+    *
+    * Unsized array constructors look like 'vec4[](a, b)', where 'a' and 'b'
+    * are vec4 variables.  In this case the size of the array being constructed
+    * is determined by the number of parameters.
+    *
+    * From page 52 (page 58 of the PDF) of the GLSL 1.50 spec:
+    *
+    *    "There must be exactly the same number of arguments as the size of
+    *    the array being constructed. If no size is present in the
+    *    constructor, then the array is explicitly sized to the number of
+    *    arguments provided. The arguments are assigned in order, starting at
+    *    element 0, to the elements of the constructed array. Each argument
+    *    must be the same type as the element type of the array, or be a type
+    *    that can be converted to the element type of the array according to
+    *    Section 4.1.10 "Implicit Conversions.""
+    */
+   exec_list actual_parameters;
+   const unsigned parameter_count =
+      process_parameters(instructions, &actual_parameters, parameters, state);
+
+   if ((parameter_count == 0)
+       || ((constructor_type->length != 0)
+	   && (constructor_type->length != parameter_count))) {
+      const unsigned min_param = (constructor_type->length == 0)
+	 ? 1 : constructor_type->length;
+
+      _mesa_glsl_error(loc, state, "array constructor must have %s %u "
+		       "parameter%s",
+		       (constructor_type->length != 0) ? "at least" : "exactly",
+		       min_param, (min_param <= 1) ? "" : "s");
+      return ir_call::get_error_instruction(ctx);
+   }
+
+   if (constructor_type->length == 0) {
+      constructor_type =
+	 glsl_type::get_array_instance(state,
+				       constructor_type->element_type(),
+				       parameter_count);
+      assert(constructor_type != NULL);
+      assert(constructor_type->length == parameter_count);
+   }
+
+   ir_function *f = state->symbols->get_function(constructor_type->name);
+
+   /* If the constructor for this type of array does not exist, generate the
+    * prototype and add it to the symbol table.
+    */
+   if (f == NULL) {
+      f = constructor_type->generate_constructor(state->symbols);
+   }
+
+   ir_rvalue *const r =
+      process_call(instructions, f, loc, &actual_parameters, state);
+
+   assert(r != NULL);
+   assert(r->type->is_error() || (r->type == constructor_type));
+
+   return r;
+}
+
+
+/**
+ * Try to convert a record constructor to a constant expression
+ */
+static ir_constant *
+constant_record_constructor(const glsl_type *constructor_type,
+			    YYLTYPE *loc, exec_list *parameters,
+			    struct _mesa_glsl_parse_state *state)
+{
+   void *ctx = talloc_parent(state);
+   bool all_parameters_are_constant = true;
+
+   exec_node *node = parameters->head;
+   for (unsigned i = 0; i < constructor_type->length; i++) {
+      ir_instruction *ir = (ir_instruction *) node;
+
+      if (node->is_tail_sentinal()) {
+	 _mesa_glsl_error(loc, state,
+			  "insufficient parameters to constructor for `%s'",
+			  constructor_type->name);
+	 return NULL;
+      }
+
+      if (ir->type != constructor_type->fields.structure[i].type) {
+	 _mesa_glsl_error(loc, state,
+			  "parameter type mismatch in constructor for `%s' "
+			  " (%s vs %s)",
+			  constructor_type->name,
+			  ir->type->name,
+			  constructor_type->fields.structure[i].type->name);
+	 return NULL;
+      }
+
+      if (ir->as_constant() == NULL)
+	 all_parameters_are_constant = false;
+
+      node = node->next;
+   }
+
+   if (!all_parameters_are_constant)
+      return NULL;
+
+   return new(ctx) ir_constant(constructor_type, parameters);
+}
+
+
+/**
+ * Generate data for a constant matrix constructor w/a single scalar parameter
+ *
+ * Matrix constructors in GLSL can be passed a single scalar of the
+ * approriate type.  In these cases, the resulting matrix is the identity
+ * matrix multipled by the specified scalar.  This function generates data for
+ * that matrix.
+ *
+ * \param type         Type of the desired matrix.
+ * \param initializer  Scalar value used to initialize the matrix diagonal.
+ * \param data         Location to store the resulting matrix.
+ */
+void
+generate_constructor_matrix(const glsl_type *type, ir_constant *initializer,
+			    ir_constant_data *data)
+{
+   switch (type->base_type) {
+   case GLSL_TYPE_UINT:
+   case GLSL_TYPE_INT:
+      for (unsigned i = 0; i < type->components(); i++)
+	 data->u[i] = 0;
+
+      for (unsigned i = 0; i < type->matrix_columns; i++) {
+	 /* The array offset of the ith row and column of the matrix.
+	  */
+	 const unsigned idx = (i * type->vector_elements) + i;
+
+	 data->u[idx] = initializer->value.u[0];
+      }
+      break;
+
+   case GLSL_TYPE_FLOAT:
+      for (unsigned i = 0; i < type->components(); i++)
+	 data->f[i] = 0;
+
+      for (unsigned i = 0; i < type->matrix_columns; i++) {
+	 /* The array offset of the ith row and column of the matrix.
+	  */
+	 const unsigned idx = (i * type->vector_elements) + i;
+
+	 data->f[idx] = initializer->value.f[0];
+      }
+
+      break;
+
+   default:
+      assert(!"Should not get here.");
+      break;
+   }
+}
+
+
+/**
+ * Generate data for a constant vector constructor w/a single scalar parameter
+ *
+ * Vector constructors in GLSL can be passed a single scalar of the
+ * approriate type.  In these cases, the resulting vector contains the specified
+ * value in all components.  This function generates data for that vector.
+ *
+ * \param type         Type of the desired vector.
+ * \param initializer  Scalar value used to initialize the vector.
+ * \param data         Location to store the resulting vector data.
+ */
+void
+generate_constructor_vector(const glsl_type *type, ir_constant *initializer,
+			    ir_constant_data *data)
+{
+   switch (type->base_type) {
+   case GLSL_TYPE_UINT:
+   case GLSL_TYPE_INT:
+      for (unsigned i = 0; i < type->components(); i++)
+	 data->u[i] = initializer->value.u[0];
+
+      break;
+
+   case GLSL_TYPE_FLOAT:
+      for (unsigned i = 0; i < type->components(); i++)
+	 data->f[i] = initializer->value.f[0];
+
+      break;
+
+   case GLSL_TYPE_BOOL:
+      for (unsigned i = 0; i < type->components(); i++)
+	 data->b[i] = initializer->value.b[0];
+
+      break;
+
+   default:
+      assert(!"Should not get here.");
+      break;
+   }
+}
+
+
+ir_rvalue *
+ast_function_expression::hir(exec_list *instructions,
+			     struct _mesa_glsl_parse_state *state)
+{
+   void *ctx = talloc_parent(state);
+   /* There are three sorts of function calls.
+    *
+    * 1. contstructors - The first subexpression is an ast_type_specifier.
+    * 2. methods - Only the .length() method of array types.
+    * 3. functions - Calls to regular old functions.
+    *
+    * Method calls are actually detected when the ast_field_selection
+    * expression is handled.
+    */
+   if (is_constructor()) {
+      const ast_type_specifier *type = (ast_type_specifier *) subexpressions[0];
+      YYLTYPE loc = type->get_location();
+      const char *name;
+
+      const glsl_type *const constructor_type = type->glsl_type(& name, state);
+
+
+      /* Constructors for samplers are illegal.
+       */
+      if (constructor_type->is_sampler()) {
+	 _mesa_glsl_error(& loc, state, "cannot construct sampler type `%s'",
+			  constructor_type->name);
+	 return ir_call::get_error_instruction(ctx);
+      }
+
+      if (constructor_type->is_array()) {
+	 if (state->language_version <= 110) {
+	    _mesa_glsl_error(& loc, state,
+			     "array constructors forbidden in GLSL 1.10");
+	    return ir_call::get_error_instruction(ctx);
+	 }
+
+	 return process_array_constructor(instructions, constructor_type,
+					  & loc, &this->expressions, state);
+      }
+
+      /* There are two kinds of constructor call.  Constructors for built-in
+       * language types, such as mat4 and vec2, are free form.  The only
+       * requirement is that the parameters must provide enough values of the
+       * correct scalar type.  Constructors for arrays and structures must
+       * have the exact number of parameters with matching types in the
+       * correct order.  These constructors follow essentially the same type
+       * matching rules as functions.
+       */
+      if (constructor_type->is_numeric() || constructor_type->is_boolean()) {
+	 /* Constructing a numeric type has a couple steps.  First all values
+	  * passed to the constructor are broken into individual parameters
+	  * and type converted to the base type of the thing being constructed.
+	  *
+	  * At that point we have some number of values that match the base
+	  * type of the thing being constructed.  Now the constructor can be
+	  * treated like a function call.  Each numeric type has a small set
+	  * of constructor functions.  The set of new parameters will either
+	  * match one of those functions or the original constructor is
+	  * invalid.
+	  */
+	 const glsl_type *const base_type = constructor_type->get_base_type();
+
+	 /* Total number of components of the type being constructed.
+	  */
+	 const unsigned type_components = constructor_type->components();
+
+	 /* Number of components from parameters that have actually been
+	  * consumed.  This is used to perform several kinds of error checking.
+	  */
+	 unsigned components_used = 0;
+
+	 unsigned matrix_parameters = 0;
+	 unsigned nonmatrix_parameters = 0;
+	 exec_list actual_parameters;
+
+	 bool all_parameters_are_constant = true;
+
+	 /* This handles invalid constructor calls such as 'vec4 v = vec4();'
+	  */
+	 if (this->expressions.is_empty()) {
+	    _mesa_glsl_error(& loc, state, "too few components to construct "
+			     "`%s'",
+			     constructor_type->name);
+	    return ir_call::get_error_instruction(ctx);
+	 }
+
+	 foreach_list (n, &this->expressions) {
+	    ast_node *ast = exec_node_data(ast_node, n, link);
+	    ir_rvalue *result =
+	       ast->hir(instructions, state)->as_rvalue();
+	    ir_variable *result_var = NULL;
+
+	    /* Attempt to convert the parameter to a constant valued expression.
+	     * After doing so, track whether or not all the parameters to the
+	     * constructor are trivially constant valued expressions.
+	     */
+	    ir_rvalue *const constant =
+	       result->constant_expression_value();
+
+	    if (constant != NULL)
+	       result = constant;
+	    else
+	       all_parameters_are_constant = false;
+
+	    /* From page 50 (page 56 of the PDF) of the GLSL 1.50 spec:
+	     *
+	     *    "It is an error to provide extra arguments beyond this
+	     *    last used argument."
+	     */
+	    if (components_used >= type_components) {
+	       _mesa_glsl_error(& loc, state, "too many parameters to `%s' "
+				"constructor",
+				constructor_type->name);
+	       return ir_call::get_error_instruction(ctx);
+	    }
+
+	    if (!result->type->is_numeric() && !result->type->is_boolean()) {
+	       _mesa_glsl_error(& loc, state, "cannot construct `%s' from a "
+				"non-numeric data type",
+				constructor_type->name);
+	       return ir_call::get_error_instruction(ctx);
+	    }
+
+	    /* Count the number of matrix and nonmatrix parameters.  This
+	     * is used below to enforce some of the constructor rules.
+	     */
+	    if (result->type->is_matrix())
+	       matrix_parameters++;
+	    else
+	       nonmatrix_parameters++;
+
+	    /* We can't use the same instruction node in the multiple
+	     * swizzle dereferences that happen, so assign it to a
+	     * variable and deref that.  Plus it saves computation for
+	     * complicated expressions and handles
+	     * glsl-vs-constructor-call.shader_test.
+	     */
+	    if (result->type->components() >= 1 && !result->as_constant()) {
+	       result_var = new(ctx) ir_variable(result->type,
+						 "constructor_tmp");
+	       ir_dereference_variable *lhs;
+
+	       lhs = new(ctx) ir_dereference_variable(result_var);
+	       instructions->push_tail(new(ctx) ir_assignment(lhs,
+							      result, NULL));
+	    }
+
+	    /* Process each of the components of the parameter.  Dereference
+	     * each component individually, perform any type conversions, and
+	     * add it to the parameter list for the constructor.
+	     */
+	    for (unsigned i = 0; i < result->type->components(); i++) {
+	       if (components_used >= type_components)
+		  break;
+
+	       ir_rvalue *component;
+
+	       if (result_var) {
+		  ir_dereference *d = new(ctx) ir_dereference_variable(result_var);
+		  component = dereference_component(d, i);
+	       } else {
+		  component = dereference_component(result, i);
+	       }
+	       component = convert_component(component, base_type);
+
+	       /* All cases that could result in component->type being the
+		* error type should have already been caught above.
+		*/
+	       assert(component->type == base_type);
+
+	       if (component->as_constant() == NULL)
+		  all_parameters_are_constant = false;
+
+	       /* Don't actually generate constructor calls for scalars.
+		* Instead, do the usual component selection and conversion,
+		* and return the single component.
+		*/
+	       if (constructor_type->is_scalar())
+		  return component;
+
+	       actual_parameters.push_tail(component);
+	       components_used++;
+	    }
+	 }
+
+	 /* From page 28 (page 34 of the PDF) of the GLSL 1.10 spec:
+	  *
+	  *    "It is an error to construct matrices from other matrices. This
+	  *    is reserved for future use."
+	  */
+	 if ((state->language_version <= 110) && (matrix_parameters > 0)
+	     && constructor_type->is_matrix()) {
+	    _mesa_glsl_error(& loc, state, "cannot construct `%s' from a "
+			     "matrix in GLSL 1.10",
+			     constructor_type->name);
+	    return ir_call::get_error_instruction(ctx);
+	 }
+
+	 /* From page 50 (page 56 of the PDF) of the GLSL 1.50 spec:
+	  *
+	  *    "If a matrix argument is given to a matrix constructor, it is
+	  *    an error to have any other arguments."
+	  */
+	 if ((matrix_parameters > 0)
+	     && ((matrix_parameters + nonmatrix_parameters) > 1)
+	     && constructor_type->is_matrix()) {
+	    _mesa_glsl_error(& loc, state, "for matrix `%s' constructor, "
+			     "matrix must be only parameter",
+			     constructor_type->name);
+	    return ir_call::get_error_instruction(ctx);
+	 }
+
+	 /* From page 28 (page 34 of the PDF) of the GLSL 1.10 spec:
+	  *
+	  *    "In these cases, there must be enough components provided in the
+	  *    arguments to provide an initializer for every component in the
+	  *    constructed value."
+	  */
+	 if ((components_used < type_components) && (components_used != 1)) {
+	    _mesa_glsl_error(& loc, state, "too few components to construct "
+			     "`%s'",
+			     constructor_type->name);
+	    return ir_call::get_error_instruction(ctx);
+	 }
+
+	 ir_function *f = state->symbols->get_function(constructor_type->name);
+	 if (f == NULL) {
+	    _mesa_glsl_error(& loc, state, "no constructor for type `%s'",
+			     constructor_type->name);
+	    return ir_call::get_error_instruction(ctx);
+	 }
+
+	 const ir_function_signature *sig =
+	    f->matching_signature(& actual_parameters);
+	 if (sig != NULL) {
+	    /* If all of the parameters are trivially constant, create a
+	     * constant representing the complete collection of parameters.
+	     */
+	    if (all_parameters_are_constant) {
+	       if (components_used >= type_components)
+		  return new(ctx) ir_constant(sig->return_type,
+					      & actual_parameters);
+
+	       assert(sig->return_type->is_vector()
+		      || sig->return_type->is_matrix());
+
+	       /* Constructors with exactly one component are special for
+		* vectors and matrices.  For vectors it causes all elements of
+		* the vector to be filled with the value.  For matrices it
+		* causes the matrix to be filled with 0 and the diagonal to be
+		* filled with the value.
+		*/
+	       ir_constant_data data;
+	       ir_constant *const initializer =
+		  (ir_constant *) actual_parameters.head;
+	       if (sig->return_type->is_matrix())
+		  generate_constructor_matrix(sig->return_type, initializer,
+					      &data);
+	       else
+		  generate_constructor_vector(sig->return_type, initializer,
+					      &data);
+
+	       return new(ctx) ir_constant(sig->return_type, &data);
+	    } else
+	       return new(ctx) ir_call(sig, & actual_parameters);
+	 } else {
+	    /* FINISHME: Log a better error message here.  G++ will show the
+	     * FINSIHME: types of the actual parameters and the set of
+	     * FINSIHME: candidate functions.  A different error should also be
+	     * FINSIHME: logged when multiple functions match.
+	     */
+	    _mesa_glsl_error(& loc, state, "no matching constructor for `%s'",
+			     constructor_type->name);
+	    return ir_call::get_error_instruction(ctx);
+	 }
+      }
+
+      return ir_call::get_error_instruction(ctx);
+   } else {
+      const ast_expression *id = subexpressions[0];
+      YYLTYPE loc = id->get_location();
+      exec_list actual_parameters;
+
+      process_parameters(instructions, &actual_parameters, &this->expressions,
+			 state);
+
+      const glsl_type *const type =
+	 state->symbols->get_type(id->primary_expression.identifier);
+
+      if ((type != NULL) && type->is_record()) {
+	 ir_constant *constant =
+	    constant_record_constructor(type, &loc, &actual_parameters, state);
+
+	 if (constant != NULL)
+	    return constant;
+      }
+
+      return match_function_by_name(instructions, 
+				    id->primary_expression.identifier, & loc,
+				    &actual_parameters, state);
+   }
+
+   return ir_call::get_error_instruction(ctx);
+}