X-Git-Url: https://git.libre-soc.org/?a=blobdiff_plain;f=src%2Fglsl%2Fast_function.cpp;h=26f72cf8e95ad343e8e0b772b467181087b62859;hb=af2c64063e7fb31b243d63b77e09cd19c3819d72;hp=e31f79926deaeb47217e75099e0af32536940dac;hpb=4926c5748028d33da4808f8a5473aa7b2f2bdc62;p=mesa.git

diff --git a/src/glsl/ast_function.cpp b/src/glsl/ast_function.cpp
index e31f79926de..26f72cf8e95 100644
--- a/src/glsl/ast_function.cpp
+++ b/src/glsl/ast_function.cpp
@@ -62,11 +62,13 @@ process_parameters(exec_list *instructions, exec_list *actual_parameters,
  *
  * \param return_type Return type of the function.  May be \c NULL.
  * \param name        Name of the function.
- * \param parameters  Parameter list for the function.  This may be either a
- *                    formal or actual parameter list.  Only the type is used.
+ * \param parameters  List of \c ir_instruction nodes representing the
+ *                    parameter list for the function.  This may be either a
+ *                    formal (\c ir_variable) or actual (\c ir_rvalue)
+ *                    parameter list.  Only the type is used.
  *
  * \return
- * A talloced string representing the prototype of the function.
+ * A ralloced string representing the prototype of the function.
  */
 char *
 prototype_string(const glsl_type *return_type, const char *name,
@@ -75,139 +77,353 @@ prototype_string(const glsl_type *return_type, const char *name,
    char *str = NULL;
 
    if (return_type != NULL)
-      str = talloc_asprintf(str, "%s ", return_type->name);
+      str = ralloc_asprintf(NULL, "%s ", return_type->name);
 
-   str = talloc_asprintf_append(str, "%s(", name);
+   ralloc_asprintf_append(&str, "%s(", name);
 
    const char *comma = "";
    foreach_list(node, parameters) {
-      const ir_instruction *const param = (ir_instruction *) node;
+      const ir_variable *const param = (ir_variable *) node;
 
-      str = talloc_asprintf_append(str, "%s%s", comma, param->type->name);
+      ralloc_asprintf_append(&str, "%s%s", comma, param->type->name);
       comma = ", ";
    }
 
-   str = talloc_strdup_append(str, ")");
+   ralloc_strcat(&str, ")");
    return str;
 }
 
-
-static ir_rvalue *
-process_call(exec_list *instructions, ir_function *f,
-	     YYLTYPE *loc, exec_list *actual_parameters,
-	     struct _mesa_glsl_parse_state *state)
+/**
+ * Verify that 'out' and 'inout' actual parameters are lvalues.  Also, verify
+ * that 'const_in' formal parameters (an extension in our IR) correspond to
+ * ir_constant actual parameters.
+ */
+static bool
+verify_parameter_modes(_mesa_glsl_parse_state *state,
+		       ir_function_signature *sig,
+		       exec_list &actual_ir_parameters,
+		       exec_list &actual_ast_parameters)
 {
-   void *ctx = state;
+   exec_node *actual_ir_node  = actual_ir_parameters.head;
+   exec_node *actual_ast_node = actual_ast_parameters.head;
 
-   ir_function_signature *sig = f->matching_signature(actual_parameters);
+   foreach_list(formal_node, &sig->parameters) {
+      /* The lists must be the same length. */
+      assert(!actual_ir_node->is_tail_sentinel());
+      assert(!actual_ast_node->is_tail_sentinel());
 
-   /* The instructions param will be used when the FINISHMEs below are done */
-   (void) instructions;
+      const ir_variable *const formal = (ir_variable *) formal_node;
+      const ir_rvalue *const actual = (ir_rvalue *) actual_ir_node;
+      const ast_expression *const actual_ast =
+	 exec_node_data(ast_expression, actual_ast_node, link);
 
-   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.
+      /* FIXME: 'loc' is incorrect (as of 2011-01-21). It is always
+       * FIXME: 0:0(0).
        */
-      exec_list_iterator actual_iter = actual_parameters->iterator();
-      exec_list_iterator formal_iter = sig->parameters.iterator();
+      YYLTYPE loc = actual_ast->get_location();
+
+      /* Verify that 'const_in' parameters are ir_constants. */
+      if (formal->mode == ir_var_const_in &&
+	  actual->ir_type != ir_type_constant) {
+	 _mesa_glsl_error(&loc, state,
+			  "parameter `in %s' must be a constant expression",
+			  formal->name);
+	 return false;
+      }
 
-      while (actual_iter.has_next()) {
-	 ir_rvalue *actual = (ir_rvalue *) actual_iter.get();
-	 ir_variable *formal = (ir_variable *) formal_iter.get();
+      /* Verify that 'out' and 'inout' actual parameters are lvalues. */
+      if (formal->mode == ir_var_function_out
+          || formal->mode == ir_var_function_inout) {
+	 const char *mode = NULL;
+	 switch (formal->mode) {
+	 case ir_var_function_out:   mode = "out";   break;
+	 case ir_var_function_inout: mode = "inout"; break;
+	 default:                    assert(false);  break;
+	 }
 
-	 assert(actual != NULL);
-	 assert(formal != NULL);
+	 /* This AST-based check catches errors like f(i++).  The IR-based
+	  * is_lvalue() is insufficient because the actual parameter at the
+	  * IR-level is just a temporary value, which is an l-value.
+	  */
+	 if (actual_ast->non_lvalue_description != NULL) {
+	    _mesa_glsl_error(&loc, state,
+			     "function parameter '%s %s' references a %s",
+			     mode, formal->name,
+			     actual_ast->non_lvalue_description);
+	    return false;
+	 }
 
-	 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");
-	    }
+	 ir_variable *var = actual->variable_referenced();
+	 if (var)
+	    var->assigned = true;
+
+	 if (var && var->read_only) {
+	    _mesa_glsl_error(&loc, state,
+			     "function parameter '%s %s' references the "
+			     "read-only variable '%s'",
+			     mode, formal->name,
+			     actual->variable_referenced()->name);
+	    return false;
+	 } else if (!actual->is_lvalue()) {
+	    _mesa_glsl_error(&loc, state,
+			     "function parameter '%s %s' is not an lvalue",
+			     mode, formal->name);
+	    return false;
 	 }
+      }
+
+      actual_ir_node  = actual_ir_node->next;
+      actual_ast_node = actual_ast_node->next;
+   }
+   return true;
+}
+
+/**
+ * If a function call is generated, \c call_ir will point to it on exit.
+ * Otherwise \c call_ir will be set to \c NULL.
+ */
+static ir_rvalue *
+generate_call(exec_list *instructions, ir_function_signature *sig,
+	      exec_list *actual_parameters,
+	      ir_call **call_ir,
+	      struct _mesa_glsl_parse_state *state)
+{
+   void *ctx = state;
+   exec_list post_call_conversions;
 
-	 if (formal->type->is_numeric() || formal->type->is_boolean()) {
-	    ir_rvalue *converted = convert_component(actual, formal->type);
+   *call_ir = NULL;
+
+   /* Perform implicit conversion of arguments.  For out parameters, we need
+    * to place them in a temporary variable and do the conversion after the
+    * call takes place.  Since we haven't emitted the call yet, we'll place
+    * the post-call conversions in a temporary exec_list, and emit them later.
+    */
+   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->type->is_numeric() || formal->type->is_boolean()) {
+	 switch (formal->mode) {
+	 case ir_var_const_in:
+	 case ir_var_function_in: {
+	    ir_rvalue *converted
+	       = convert_component(actual, formal->type);
 	    actual->replace_with(converted);
+	    break;
+	 }
+	 case ir_var_function_out:
+	    if (actual->type != formal->type) {
+	       /* To convert an out parameter, we need to create a
+		* temporary variable to hold the value before conversion,
+		* and then perform the conversion after the function call
+		* returns.
+		*
+		* This has the effect of transforming code like this:
+		*
+		*   void f(out int x);
+		*   float value;
+		*   f(value);
+		*
+		* Into IR that's equivalent to this:
+		*
+		*   void f(out int x);
+		*   float value;
+		*   int out_parameter_conversion;
+		*   f(out_parameter_conversion);
+		*   value = float(out_parameter_conversion);
+		*/
+	       ir_variable *tmp =
+		  new(ctx) ir_variable(formal->type,
+				       "out_parameter_conversion",
+				       ir_var_temporary);
+	       instructions->push_tail(tmp);
+	       ir_dereference_variable *deref_tmp_1
+		  = new(ctx) ir_dereference_variable(tmp);
+	       ir_dereference_variable *deref_tmp_2
+		  = new(ctx) ir_dereference_variable(tmp);
+	       ir_rvalue *converted_tmp
+		  = convert_component(deref_tmp_1, actual->type);
+	       ir_assignment *assignment
+		  = new(ctx) ir_assignment(actual, converted_tmp);
+	       post_call_conversions.push_tail(assignment);
+	       actual->replace_with(deref_tmp_2);
+	    }
+	    break;
+	 case ir_var_function_inout:
+	    /* Inout parameters should never require conversion, since that
+	     * would require an implicit conversion to exist both to and
+	     * from the formal parameter type, and there are no
+	     * bidirectional implicit conversions.
+	     */
+	    assert (actual->type == formal->type);
+	    break;
+	 default:
+	    assert (!"Illegal formal parameter mode");
+	    break;
 	 }
-
-	 actual_iter.next();
-	 formal_iter.next();
       }
 
-      /* Always insert the call in the instruction stream, and return a deref
-       * of its return val if it returns a value, since we don't know if
-       * the rvalue is going to be assigned to anything or not.
-       */
-      ir_call *call = new(ctx) ir_call(sig, actual_parameters);
-      if (!sig->return_type->is_void()) {
-	 ir_variable *var;
-	 ir_dereference_variable *deref;
-
-	 var = new(ctx) ir_variable(sig->return_type,
-				    talloc_asprintf(ctx, "%s_retval",
-						    sig->function_name()),
-				    ir_var_temporary);
-	 instructions->push_tail(var);
-
-	 deref = new(ctx) ir_dereference_variable(var);
-	 ir_assignment *assign = new(ctx) ir_assignment(deref, call, NULL);
-	 instructions->push_tail(assign);
-	 if (state->language_version >= 120)
-	    var->constant_value = call->constant_expression_value();
-
-	 deref = new(ctx) ir_dereference_variable(var);
-	 return deref;
-      } else {
-	 instructions->push_tail(call);
-	 return NULL;
+      actual_iter.next();
+      formal_iter.next();
+   }
+
+   /* If the function call is a constant expression, don't generate any
+    * instructions; just generate an ir_constant.
+    *
+    * Function calls were first allowed to be constant expressions in GLSL
+    * 1.20 and GLSL ES 3.00.
+    */
+   if (state->is_version(120, 300)) {
+      ir_constant *value = sig->constant_expression_value(actual_parameters, NULL);
+      if (value != NULL) {
+	 return value;
       }
-   } else {
-      char *str = prototype_string(NULL, f->name, actual_parameters);
+   }
 
-      _mesa_glsl_error(loc, state, "no matching function for call to `%s'",
-		       str);
-      talloc_free(str);
+   ir_dereference_variable *deref = NULL;
+   if (!sig->return_type->is_void()) {
+      /* Create a new temporary to hold the return value. */
+      ir_variable *var;
 
-      const char *prefix = "candidates are: ";
-      foreach_list (node, &f->signatures) {
-	 ir_function_signature *sig = (ir_function_signature *) node;
+      var = new(ctx) ir_variable(sig->return_type,
+				 ralloc_asprintf(ctx, "%s_retval",
+						 sig->function_name()),
+				 ir_var_temporary);
+      instructions->push_tail(var);
 
-	 str = prototype_string(sig->return_type, f->name, &sig->parameters);
-	 _mesa_glsl_error(loc, state, "%s%s\n", prefix, str);
-	 talloc_free(str);
+      deref = new(ctx) ir_dereference_variable(var);
+   }
+   ir_call *call = new(ctx) ir_call(sig, deref, actual_parameters);
+   instructions->push_tail(call);
 
-	 prefix = "                ";
-      }
+   /* Also emit any necessary out-parameter conversions. */
+   instructions->append_list(&post_call_conversions);
 
-      return ir_call::get_error_instruction(ctx);
-   }
+   return deref ? deref->clone(ctx, NULL) : NULL;
 }
 
-
-static ir_rvalue *
-match_function_by_name(exec_list *instructions, const char *name,
-		       YYLTYPE *loc, exec_list *actual_parameters,
+/**
+ * Given a function name and parameter list, find the matching signature.
+ */
+static ir_function_signature *
+match_function_by_name(const char *name,
+		       exec_list *actual_parameters,
 		       struct _mesa_glsl_parse_state *state)
 {
    void *ctx = state;
    ir_function *f = state->symbols->get_function(name);
+   ir_function_signature *local_sig = NULL;
+   ir_function_signature *sig = NULL;
+
+   /* Is the function hidden by a record type constructor? */
+   if (state->symbols->get_type(name))
+      goto done; /* no match */
+
+   /* Is the function hidden by a variable (impossible in 1.10)? */
+   if (!state->symbols->separate_function_namespace
+       && state->symbols->get_variable(name))
+      goto done; /* no match */
+
+   if (f != NULL) {
+      /* Look for a match in the local shader.  If exact, we're done. */
+      bool is_exact = false;
+      sig = local_sig = f->matching_signature(actual_parameters, &is_exact);
+      if (is_exact)
+	 goto done;
+
+      if (!state->es_shader && f->has_user_signature()) {
+	 /* In desktop GL, the presence of a user-defined signature hides any
+	  * built-in signatures, so we must ignore them.  In contrast, in ES2
+	  * user-defined signatures add new overloads, so we must proceed.
+	  */
+	 goto done;
+      }
+   }
+
+   /* Local shader has no exact candidates; check the built-ins. */
+   _mesa_glsl_initialize_functions(state);
+   for (unsigned i = 0; i < state->num_builtins_to_link; i++) {
+      ir_function *builtin =
+	 state->builtins_to_link[i]->symbols->get_function(name);
+      if (builtin == NULL)
+	 continue;
+
+      bool is_exact = false;
+      ir_function_signature *builtin_sig =
+	 builtin->matching_signature(actual_parameters, &is_exact);
+
+      if (builtin_sig == NULL)
+	 continue;
+
+      /* If the built-in signature is exact, we can stop. */
+      if (is_exact) {
+	 sig = builtin_sig;
+	 goto done;
+      }
 
-   if (f == NULL) {
-      _mesa_glsl_error(loc, state, "function `%s' undeclared", name);
-      return ir_call::get_error_instruction(ctx);
+      if (sig == NULL) {
+	 /* We found an inexact match, which is better than nothing.  However,
+	  * we should keep searching for an exact match.
+	  */
+	 sig = builtin_sig;
+      }
    }
 
-   /* 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);
+done:
+   if (sig != NULL) {
+      /* If the match is from a linked built-in shader, import the prototype. */
+      if (sig != local_sig) {
+	 if (f == NULL) {
+	    f = new(ctx) ir_function(name);
+	    state->symbols->add_global_function(f);
+	    emit_function(state, f);
+	 }
+	 f->add_signature(sig->clone_prototype(f, NULL));
+      }
+   }
+   return sig;
 }
 
+/**
+ * Raise a "no matching function" error, listing all possible overloads the
+ * compiler considered so developers can figure out what went wrong.
+ */
+static void
+no_matching_function_error(const char *name,
+			   YYLTYPE *loc,
+			   exec_list *actual_parameters,
+			   _mesa_glsl_parse_state *state)
+{
+   char *str = prototype_string(NULL, name, actual_parameters);
+   _mesa_glsl_error(loc, state, "no matching function for call to `%s'", str);
+   ralloc_free(str);
+
+   const char *prefix = "candidates are: ";
+
+   for (int i = -1; i < (int) state->num_builtins_to_link; i++) {
+      glsl_symbol_table *syms = i >= 0 ? state->builtins_to_link[i]->symbols
+				       : state->symbols;
+      ir_function *f = syms->get_function(name);
+      if (f == NULL)
+	 continue;
+
+      foreach_list (node, &f->signatures) {
+	 ir_function_signature *sig = (ir_function_signature *) node;
+
+	 str = prototype_string(sig->return_type, f->name, &sig->parameters);
+	 _mesa_glsl_error(loc, state, "%s%s", prefix, str);
+	 ralloc_free(str);
+
+	 prefix = "                ";
+      }
+   }
+}
 
 /**
  * Perform automatic type conversion of constructor parameters
@@ -218,7 +434,7 @@ match_function_by_name(exec_list *instructions, const char *name,
 static ir_rvalue *
 convert_component(ir_rvalue *src, const glsl_type *desired_type)
 {
-   void *ctx = talloc_parent(src);
+   void *ctx = ralloc_parent(src);
    const unsigned a = desired_type->base_type;
    const unsigned b = src->type->base_type;
    ir_expression *result = NULL;
@@ -229,17 +445,35 @@ convert_component(ir_rvalue *src, const glsl_type *desired_type)
    assert(a <= GLSL_TYPE_BOOL);
    assert(b <= GLSL_TYPE_BOOL);
 
-   if ((a == b) || (src->type->is_integer() && desired_type->is_integer()))
+   if (a == b)
       return src;
 
    switch (a) {
    case GLSL_TYPE_UINT:
+      switch (b) {
+      case GLSL_TYPE_INT:
+	 result = new(ctx) ir_expression(ir_unop_i2u, src);
+	 break;
+      case GLSL_TYPE_FLOAT:
+	 result = new(ctx) ir_expression(ir_unop_f2u, src);
+	 break;
+      case GLSL_TYPE_BOOL:
+	 result = new(ctx) ir_expression(ir_unop_i2u,
+		  new(ctx) ir_expression(ir_unop_b2i, src));
+	 break;
+      }
+      break;
    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);
+      switch (b) {
+      case GLSL_TYPE_UINT:
+	 result = new(ctx) ir_expression(ir_unop_u2i, src);
+	 break;
+      case GLSL_TYPE_FLOAT:
+	 result = new(ctx) ir_expression(ir_unop_f2i, src);
+	 break;
+      case GLSL_TYPE_BOOL:
+	 result = new(ctx) ir_expression(ir_unop_b2i, src);
+	 break;
       }
       break;
    case GLSL_TYPE_FLOAT:
@@ -258,6 +492,9 @@ convert_component(ir_rvalue *src, const glsl_type *desired_type)
    case GLSL_TYPE_BOOL:
       switch (b) {
       case GLSL_TYPE_UINT:
+	 result = new(ctx) ir_expression(ir_unop_i2b,
+		  new(ctx) ir_expression(ir_unop_u2i, src));
+	 break;
       case GLSL_TYPE_INT:
 	 result = new(ctx) ir_expression(ir_unop_i2b, desired_type, src, NULL);
 	 break;
@@ -269,6 +506,7 @@ convert_component(ir_rvalue *src, const glsl_type *desired_type)
    }
 
    assert(result != NULL);
+   assert(result->type == desired_type);
 
    /* Try constant folding; it may fold in the conversion we just added. */
    ir_constant *const constant = result->constant_expression_value();
@@ -281,7 +519,7 @@ convert_component(ir_rvalue *src, const glsl_type *desired_type)
 static ir_rvalue *
 dereference_component(ir_rvalue *src, unsigned component)
 {
-   void *ctx = talloc_parent(src);
+   void *ctx = ralloc_parent(src);
    assert(component < src->type->components());
 
    /* If the source is a constant, just create a new constant instead of a
@@ -357,7 +595,7 @@ process_array_constructor(exec_list *instructions,
 		       "parameter%s",
 		       (constructor_type->length != 0) ? "at least" : "exactly",
 		       min_param, (min_param <= 1) ? "" : "s");
-      return ir_call::get_error_instruction(ctx);
+      return ir_rvalue::error_value(ctx);
    }
 
    if (constructor_type->length == 0) {
@@ -375,13 +613,21 @@ process_array_constructor(exec_list *instructions,
       ir_rvalue *ir = (ir_rvalue *) n;
       ir_rvalue *result = ir;
 
-      /* Apply implicit conversions (not the scalar constructor rules!) */
+      /* Apply implicit conversions (not the scalar constructor rules!). See
+       * the spec quote above. */
       if (constructor_type->element_type()->is_float()) {
 	 const glsl_type *desired_type =
 	    glsl_type::get_instance(GLSL_TYPE_FLOAT,
 				    ir->type->vector_elements,
 				    ir->type->matrix_columns);
-	 result = convert_component(ir, desired_type);
+	 if (result->type->can_implicitly_convert_to(desired_type)) {
+	    /* Even though convert_component() implements the constructor
+	     * conversion rules (not the implicit conversion rules), its safe
+	     * to use it here because we already checked that the implicit
+	     * conversion is legal.
+	     */
+	    result = convert_component(ir, desired_type);
+	 }
       }
 
       if (result->type != constructor_type->element_type()) {
@@ -580,18 +826,17 @@ emit_inline_vector_constructor(const glsl_type *type,
 
 	 const ir_constant *const c = param->as_constant();
 	 if (c == NULL) {
-	    /* Generate a swizzle in case rhs_components != rhs->type->vector_elements. */
-	    unsigned swiz[4] = { 0, 0, 0, 0 };
-	    for (unsigned i = 0; i < rhs_components; i++)
-	       swiz[i] = i;
-
 	    /* Mask of fields to be written in the assignment.
 	     */
 	    const unsigned write_mask = ((1U << rhs_components) - 1)
 	       << base_component;
 
 	    ir_dereference *lhs = new(ctx) ir_dereference_variable(var);
-	    ir_rvalue *rhs = new(ctx) ir_swizzle(param, swiz, rhs_components);
+
+	    /* Generate a swizzle so that LHS and RHS sizes match.
+	     */
+	    ir_rvalue *rhs =
+	       new(ctx) ir_swizzle(param, 0, 1, 2, 3, rhs_components);
 
 	    ir_instruction *inst =
 	       new(ctx) ir_assignment(lhs, rhs, NULL, write_mask);
@@ -631,21 +876,21 @@ assign_to_matrix_column(ir_variable *var, unsigned column, unsigned row_base,
    assert(column_ref->type->components() >= (row_base + count));
    assert(src->type->components() >= (src_base + count));
 
-   /* Generate a swizzle that puts the first element of the source at the
-    * location of the first element of the destination.
+   /* Generate a swizzle that extracts the number of components from the source
+    * that are to be assigned to the column of the matrix.
     */
-   unsigned swiz[4] = { src_base, src_base, src_base, src_base };
-   for (unsigned i = 0; i < count; i++)
-      swiz[i + row_base] = i;
-
-   ir_rvalue *const rhs =
-      new(mem_ctx) ir_swizzle(src, swiz, count);
+   if (count < src->type->vector_elements) {
+      src = new(mem_ctx) ir_swizzle(src,
+				    src_base + 0, src_base + 1,
+				    src_base + 2, src_base + 3,
+				    count);
+   }
 
    /* Mask of fields to be written in the assignment.
     */
    const unsigned write_mask = ((1U << count) - 1) << row_base;
 
-   return new(mem_ctx) ir_assignment(column_ref, rhs, NULL, write_mask);
+   return new(mem_ctx) ir_assignment(column_ref, src, NULL, write_mask);
 }
 
 
@@ -980,20 +1225,29 @@ ast_function_expression::hir(exec_list *instructions,
 
       const glsl_type *const constructor_type = type->glsl_type(& name, state);
 
+      /* constructor_type can be NULL if a variable with the same name as the
+       * structure has come into scope.
+       */
+      if (constructor_type == NULL) {
+	 _mesa_glsl_error(& loc, state, "unknown type `%s' (structure name "
+			  "may be shadowed by a variable with the same name)",
+			  type->type_name);
+	 return ir_rvalue::error_value(ctx);
+      }
+
 
       /* 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);
+	 return ir_rvalue::error_value(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);
+         if (!state->check_version(120, 300, &loc,
+                                   "array constructors forbidden")) {
+	    return ir_rvalue::error_value(ctx);
 	 }
 
 	 return process_array_constructor(instructions, constructor_type,
@@ -1009,8 +1263,59 @@ ast_function_expression::hir(exec_list *instructions,
        * correct order.  These constructors follow essentially the same type
        * matching rules as functions.
        */
+      if (constructor_type->is_record()) {
+	 exec_list actual_parameters;
+
+	 process_parameters(instructions, &actual_parameters,
+			    &this->expressions, state);
+
+	 exec_node *node = actual_parameters.head;
+	 for (unsigned i = 0; i < constructor_type->length; i++) {
+	    ir_rvalue *ir = (ir_rvalue *) node;
+
+	    if (node->is_tail_sentinel()) {
+	       _mesa_glsl_error(&loc, state,
+				"insufficient parameters to constructor "
+				"for `%s'",
+				constructor_type->name);
+	       return ir_rvalue::error_value(ctx);
+	    }
+
+	    if (apply_implicit_conversion(constructor_type->fields.structure[i].type,
+					  ir, state)) {
+	       node->replace_with(ir);
+	    } else {
+	       _mesa_glsl_error(&loc, state,
+				"parameter type mismatch in constructor "
+				"for `%s.%s' (%s vs %s)",
+				constructor_type->name,
+				constructor_type->fields.structure[i].name,
+				ir->type->name,
+				constructor_type->fields.structure[i].type->name);
+	       return ir_rvalue::error_value(ctx);;
+	    }
+
+	    node = node->next;
+	 }
+
+	 if (!node->is_tail_sentinel()) {
+	    _mesa_glsl_error(&loc, state, "too many parameters in constructor "
+			     "for `%s'", constructor_type->name);
+	    return ir_rvalue::error_value(ctx);
+	 }
+
+	 ir_rvalue *const constant =
+	    constant_record_constructor(constructor_type, &actual_parameters,
+					state);
+
+	 return (constant != NULL)
+	    ? constant
+	    : emit_inline_record_constructor(constructor_type, instructions,
+					     &actual_parameters, state);
+      }
+
       if (!constructor_type->is_numeric() && !constructor_type->is_boolean())
-	 return ir_call::get_error_instruction(ctx);
+	 return ir_rvalue::error_value(ctx);
 
       /* Total number of components of the type being constructed. */
       const unsigned type_components = constructor_type->components();
@@ -1037,14 +1342,14 @@ ast_function_expression::hir(exec_list *instructions,
 	    _mesa_glsl_error(& loc, state, "too many parameters to `%s' "
 			     "constructor",
 			     constructor_type->name);
-	    return ir_call::get_error_instruction(ctx);
+	    return ir_rvalue::error_value(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);
+	    return ir_rvalue::error_value(ctx);
 	 }
 
 	 /* Count the number of matrix and nonmatrix parameters.  This
@@ -1064,12 +1369,12 @@ ast_function_expression::hir(exec_list *instructions,
        *    "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);
+      if (matrix_parameters > 0
+          && constructor_type->is_matrix()
+          && !state->check_version(120, 100, &loc,
+                                   "cannot construct `%s' from a matrix",
+                                   constructor_type->name)) {
+	 return ir_rvalue::error_value(ctx);
       }
 
       /* From page 50 (page 56 of the PDF) of the GLSL 1.50 spec:
@@ -1083,7 +1388,7 @@ ast_function_expression::hir(exec_list *instructions,
 	 _mesa_glsl_error(& loc, state, "for matrix `%s' constructor, "
 			  "matrix must be only parameter",
 			  constructor_type->name);
-	 return ir_call::get_error_instruction(ctx);
+	 return ir_rvalue::error_value(ctx);
       }
 
       /* From page 28 (page 34 of the PDF) of the GLSL 1.10 spec:
@@ -1097,7 +1402,7 @@ ast_function_expression::hir(exec_list *instructions,
 	 _mesa_glsl_error(& loc, state, "too few components to construct "
 			  "`%s'",
 			  constructor_type->name);
-	 return ir_call::get_error_instruction(ctx);
+	 return ir_rvalue::error_value(ctx);
       }
 
       /* Later, we cast each parameter to the same base type as the
@@ -1178,64 +1483,31 @@ ast_function_expression::hir(exec_list *instructions,
       }
    } else {
       const ast_expression *id = subexpressions[0];
+      const char *func_name = id->primary_expression.identifier;
       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()) {
-	 exec_node *node = actual_parameters.head;
-	 for (unsigned i = 0; i < type->length; i++) {
-	    ir_rvalue *ir = (ir_rvalue *) node;
-
-	    if (node->is_tail_sentinel()) {
-	       _mesa_glsl_error(&loc, state,
-				"insufficient parameters to constructor "
-				"for `%s'",
-				type->name);
-	       return ir_call::get_error_instruction(ctx);
-	    }
-
-	    if (apply_implicit_conversion(type->fields.structure[i].type, ir,
-					  state)) {
-	       node->replace_with(ir);
-	    } else {
-	       _mesa_glsl_error(&loc, state,
-				"parameter type mismatch in constructor "
-				"for `%s.%s' (%s vs %s)",
-				type->name,
-				type->fields.structure[i].name,
-				ir->type->name,
-				type->fields.structure[i].type->name);
-	       return ir_call::get_error_instruction(ctx);;
-	    }
-
-	    node = node->next;
-	 }
-
-	 if (!node->is_tail_sentinel()) {
-	    _mesa_glsl_error(&loc, state, "too many parameters in constructor "
-			     "for `%s'", type->name);
-	    return ir_call::get_error_instruction(ctx);
-	 }
-
-	 ir_rvalue *const constant =
-	    constant_record_constructor(type, &actual_parameters, state);
-
-	 return (constant != NULL)
-	    ? constant
-	    : emit_inline_record_constructor(type, instructions,
-					     &actual_parameters, state);
+      ir_function_signature *sig =
+	 match_function_by_name(func_name, &actual_parameters, state);
+
+      ir_call *call = NULL;
+      ir_rvalue *value = NULL;
+      if (sig == NULL) {
+	 no_matching_function_error(func_name, &loc, &actual_parameters, state);
+	 value = ir_rvalue::error_value(ctx);
+      } else if (!verify_parameter_modes(state, sig, actual_parameters, this->expressions)) {
+	 /* an error has already been emitted */
+	 value = ir_rvalue::error_value(ctx);
+      } else {
+	 value = generate_call(instructions, sig, &actual_parameters,
+			       &call, state);
       }
 
-      return match_function_by_name(instructions, 
-				    id->primary_expression.identifier, & loc,
-				    &actual_parameters, state);
+      return value;
    }
 
-   return ir_call::get_error_instruction(ctx);
+   return ir_rvalue::error_value(ctx);
 }