glsl: Don't mark assignment temporaries as read-only
[mesa.git] / src / glsl / ast_to_hir.cpp
index 3b87f0d56de8543fd2099e1bba5b0760ce37f0b0..1aebca40facf35a115c8fc06b5a6b340d78e0495 100644 (file)
@@ -60,12 +60,13 @@ void
 _mesa_ast_to_hir(exec_list *instructions, struct _mesa_glsl_parse_state *state)
 {
    _mesa_glsl_initialize_variables(instructions, state);
-   _mesa_glsl_initialize_functions(state);
 
    state->symbols->language_version = state->language_version;
 
    state->current_function = NULL;
 
+   state->toplevel_ir = instructions;
+
    /* Section 4.2 of the GLSL 1.20 specification states:
     * "The built-in functions are scoped in a scope outside the global scope
     *  users declare global variables in.  That is, a shader's global scope,
@@ -83,6 +84,10 @@ _mesa_ast_to_hir(exec_list *instructions, struct _mesa_glsl_parse_state *state)
 
    foreach_list_typed (ast_node, ast, link, & state->translation_unit)
       ast->hir(instructions, state);
+
+   detect_recursion_unlinked(state, instructions);
+
+   state->toplevel_ir = NULL;
 }
 
 
@@ -447,9 +452,17 @@ modulus_result_type(const struct glsl_type *type_a,
     *    integer vectors. The operand types must both be signed or both be
     *    unsigned."
     */
-   if (!type_a->is_integer() || !type_b->is_integer()
-       || (type_a->base_type != type_b->base_type)) {
-      _mesa_glsl_error(loc, state, "type mismatch");
+   if (!type_a->is_integer()) {
+      _mesa_glsl_error(loc, state, "LHS of operator %% must be an integer.");
+      return glsl_type::error_type;
+   }
+   if (!type_b->is_integer()) {
+      _mesa_glsl_error(loc, state, "RHS of operator %% must be an integer.");
+      return glsl_type::error_type;
+   }
+   if (type_a->base_type != type_b->base_type) {
+      _mesa_glsl_error(loc, state,
+                      "operands of %% must have the same base type");
       return glsl_type::error_type;
    }
 
@@ -639,8 +652,19 @@ validate_assignment(struct _mesa_glsl_parse_state *state,
    return NULL;
 }
 
+static void
+mark_whole_array_access(ir_rvalue *access)
+{
+   ir_dereference_variable *deref = access->as_dereference_variable();
+
+   if (deref && deref->var) {
+      deref->var->max_array_access = deref->type->length - 1;
+   }
+}
+
 ir_rvalue *
 do_assignment(exec_list *instructions, struct _mesa_glsl_parse_state *state,
+             const char *non_lvalue_description,
              ir_rvalue *lhs, ir_rvalue *rhs, bool is_initializer,
              YYLTYPE lhs_loc)
 {
@@ -648,23 +672,32 @@ do_assignment(exec_list *instructions, struct _mesa_glsl_parse_state *state,
    bool error_emitted = (lhs->type->is_error() || rhs->type->is_error());
 
    if (!error_emitted) {
-      if (lhs->variable_referenced() != NULL
-          && lhs->variable_referenced()->read_only) {
+      if (non_lvalue_description != NULL) {
+         _mesa_glsl_error(&lhs_loc, state,
+                          "assignment to %s",
+                         non_lvalue_description);
+        error_emitted = true;
+      } else if (lhs->variable_referenced() != NULL
+                && lhs->variable_referenced()->read_only) {
          _mesa_glsl_error(&lhs_loc, state,
                           "assignment to read-only variable '%s'",
                           lhs->variable_referenced()->name);
          error_emitted = true;
 
+      } else if (state->language_version <= 110 && lhs->type->is_array()) {
+        /* From page 32 (page 38 of the PDF) of the GLSL 1.10 spec:
+         *
+         *    "Other binary or unary expressions, non-dereferenced
+         *     arrays, function names, swizzles with repeated fields,
+         *     and constants cannot be l-values."
+         */
+        _mesa_glsl_error(&lhs_loc, state, "whole array assignment is not "
+                         "allowed in GLSL 1.10 or GLSL ES 1.00.");
+        error_emitted = true;
       } else if (!lhs->is_lvalue()) {
         _mesa_glsl_error(& lhs_loc, state, "non-lvalue in assignment");
         error_emitted = true;
       }
-
-      if (state->es_shader && lhs->type->is_array()) {
-        _mesa_glsl_error(&lhs_loc, state, "whole array assignment is not "
-                         "allowed in GLSL ES 1.00.");
-        error_emitted = true;
-      }
    }
 
    ir_rvalue *new_rhs =
@@ -699,6 +732,8 @@ do_assignment(exec_list *instructions, struct _mesa_glsl_parse_state *state,
                                                   rhs->type->array_size());
         d->type = var->type;
       }
+      mark_whole_array_access(rhs);
+      mark_whole_array_access(lhs);
    }
 
    /* Most callers of do_assignment (assign, add_assign, pre_inc/dec,
@@ -740,11 +775,6 @@ get_lvalue_copy(exec_list *instructions, ir_rvalue *lvalue)
    instructions->push_tail(new(ctx) ir_assignment(new(ctx) ir_dereference_variable(var),
                                                  lvalue, NULL));
 
-   /* Once we've created this temporary, mark it read only so it's no
-    * longer considered an lvalue.
-    */
-   var->read_only = true;
-
    return new(ctx) ir_dereference_variable(var);
 }
 
@@ -759,16 +789,6 @@ ast_node::hir(exec_list *instructions,
    return NULL;
 }
 
-static void
-mark_whole_array_access(ir_rvalue *access)
-{
-   ir_dereference_variable *deref = access->as_dereference_variable();
-
-   if (deref) {
-      deref->var->max_array_access = deref->type->length - 1;
-   }
-}
-
 static ir_rvalue *
 do_comparison(void *mem_ctx, int operation, ir_rvalue *op0, ir_rvalue *op1)
 {
@@ -878,6 +898,66 @@ get_scalar_boolean_operand(exec_list *instructions,
    return new(ctx) ir_constant(true);
 }
 
+/**
+ * If name refers to a builtin array whose maximum allowed size is less than
+ * size, report an error and return true.  Otherwise return false.
+ */
+static bool
+check_builtin_array_max_size(const char *name, unsigned size,
+                             YYLTYPE loc, struct _mesa_glsl_parse_state *state)
+{
+   if ((strcmp("gl_TexCoord", name) == 0)
+       && (size > state->Const.MaxTextureCoords)) {
+      /* From page 54 (page 60 of the PDF) of the GLSL 1.20 spec:
+       *
+       *     "The size [of gl_TexCoord] can be at most
+       *     gl_MaxTextureCoords."
+       */
+      _mesa_glsl_error(&loc, state, "`gl_TexCoord' array size cannot "
+                       "be larger than gl_MaxTextureCoords (%u)\n",
+                       state->Const.MaxTextureCoords);
+      return true;
+   } else if (strcmp("gl_ClipDistance", name) == 0
+              && size > state->Const.MaxClipPlanes) {
+      /* From section 7.1 (Vertex Shader Special Variables) of the
+       * GLSL 1.30 spec:
+       *
+       *   "The gl_ClipDistance array is predeclared as unsized and
+       *   must be sized by the shader either redeclaring it with a
+       *   size or indexing it only with integral constant
+       *   expressions. ... The size can be at most
+       *   gl_MaxClipDistances."
+       */
+      _mesa_glsl_error(&loc, state, "`gl_ClipDistance' array size cannot "
+                       "be larger than gl_MaxClipDistances (%u)\n",
+                       state->Const.MaxClipPlanes);
+      return true;
+   }
+   return false;
+}
+
+/**
+ * Create the constant 1, of a which is appropriate for incrementing and
+ * decrementing values of the given GLSL type.  For example, if type is vec4,
+ * this creates a constant value of 1.0 having type float.
+ *
+ * If the given type is invalid for increment and decrement operators, return
+ * a floating point 1--the error will be detected later.
+ */
+static ir_rvalue *
+constant_one_for_inc_dec(void *ctx, const glsl_type *type)
+{
+   switch (type->base_type) {
+   case GLSL_TYPE_UINT:
+      return new(ctx) ir_constant((unsigned) 1);
+   case GLSL_TYPE_INT:
+      return new(ctx) ir_constant(1);
+   default:
+   case GLSL_TYPE_FLOAT:
+      return new(ctx) ir_constant(1.0f);
+   }
+}
+
 ir_rvalue *
 ast_expression::hir(exec_list *instructions,
                    struct _mesa_glsl_parse_state *state)
@@ -951,7 +1031,9 @@ ast_expression::hir(exec_list *instructions,
       op[0] = this->subexpressions[0]->hir(instructions, state);
       op[1] = this->subexpressions[1]->hir(instructions, state);
 
-      result = do_assignment(instructions, state, op[0], op[1], false,
+      result = do_assignment(instructions, state,
+                            this->subexpressions[0]->non_lvalue_description,
+                            op[0], op[1], false,
                             this->subexpressions[0]->get_location());
       error_emitted = result->type->is_error();
       break;
@@ -1105,7 +1187,7 @@ ast_expression::hir(exec_list *instructions,
         error_emitted = true;
       }
 
-      type = op[0]->type;
+      type = error_emitted ? glsl_type::error_type : op[0]->type;
       result = new(ctx) ir_expression(ir_unop_bit_not, type, op[0], NULL);
       break;
 
@@ -1231,6 +1313,7 @@ ast_expression::hir(exec_list *instructions,
                                                   op[0], op[1]);
 
       result = do_assignment(instructions, state,
+                            this->subexpressions[0]->non_lvalue_description,
                             op[0]->clone(ctx, NULL), temp_rhs, false,
                             this->subexpressions[0]->get_location());
       error_emitted = (op[0]->type->is_error());
@@ -1256,6 +1339,7 @@ ast_expression::hir(exec_list *instructions,
                                        op[0], op[1]);
 
       result = do_assignment(instructions, state,
+                            this->subexpressions[0]->non_lvalue_description,
                             op[0]->clone(ctx, NULL), temp_rhs, false,
                             this->subexpressions[0]->get_location());
       error_emitted = type->is_error();
@@ -1270,8 +1354,9 @@ ast_expression::hir(exec_list *instructions,
                                &loc);
       ir_rvalue *temp_rhs = new(ctx) ir_expression(operations[this->oper],
                                                    type, op[0], op[1]);
-      result = do_assignment(instructions, state, op[0]->clone(ctx, NULL),
-                             temp_rhs, false,
+      result = do_assignment(instructions, state,
+                            this->subexpressions[0]->non_lvalue_description,
+                            op[0]->clone(ctx, NULL), temp_rhs, false,
                              this->subexpressions[0]->get_location());
       error_emitted = op[0]->type->is_error() || op[1]->type->is_error();
       break;
@@ -1286,8 +1371,9 @@ ast_expression::hir(exec_list *instructions,
                                    state, &loc);
       ir_rvalue *temp_rhs = new(ctx) ir_expression(operations[this->oper],
                                                    type, op[0], op[1]);
-      result = do_assignment(instructions, state, op[0]->clone(ctx, NULL),
-                             temp_rhs, false,
+      result = do_assignment(instructions, state,
+                            this->subexpressions[0]->non_lvalue_description,
+                            op[0]->clone(ctx, NULL), temp_rhs, false,
                              this->subexpressions[0]->get_location());
       error_emitted = op[0]->type->is_error() || op[1]->type->is_error();
       break;
@@ -1384,11 +1470,11 @@ ast_expression::hir(exec_list *instructions,
 
    case ast_pre_inc:
    case ast_pre_dec: {
+      this->non_lvalue_description = (this->oper == ast_pre_inc)
+        ? "pre-increment operation" : "pre-decrement operation";
+
       op[0] = this->subexpressions[0]->hir(instructions, state);
-      if (op[0]->type->base_type == GLSL_TYPE_FLOAT)
-        op[1] = new(ctx) ir_constant(1.0f);
-      else
-        op[1] = new(ctx) ir_constant(1);
+      op[1] = constant_one_for_inc_dec(ctx, op[0]->type);
 
       type = arithmetic_result_type(op[0], op[1], false, state, & loc);
 
@@ -1397,6 +1483,7 @@ ast_expression::hir(exec_list *instructions,
                                        op[0], op[1]);
 
       result = do_assignment(instructions, state,
+                            this->subexpressions[0]->non_lvalue_description,
                             op[0]->clone(ctx, NULL), temp_rhs, false,
                             this->subexpressions[0]->get_location());
       error_emitted = op[0]->type->is_error();
@@ -1405,11 +1492,10 @@ ast_expression::hir(exec_list *instructions,
 
    case ast_post_inc:
    case ast_post_dec: {
+      this->non_lvalue_description = (this->oper == ast_post_inc)
+        ? "post-increment operation" : "post-decrement operation";
       op[0] = this->subexpressions[0]->hir(instructions, state);
-      if (op[0]->type->base_type == GLSL_TYPE_FLOAT)
-        op[1] = new(ctx) ir_constant(1.0f);
-      else
-        op[1] = new(ctx) ir_constant(1);
+      op[1] = constant_one_for_inc_dec(ctx, op[0]->type);
 
       error_emitted = op[0]->type->is_error() || op[1]->type->is_error();
 
@@ -1425,6 +1511,7 @@ ast_expression::hir(exec_list *instructions,
       result = get_lvalue_copy(instructions, op[0]->clone(ctx, NULL));
 
       (void)do_assignment(instructions, state,
+                         this->subexpressions[0]->non_lvalue_description,
                          op[0]->clone(ctx, NULL), temp_rhs, false,
                          this->subexpressions[0]->get_location());
 
@@ -1535,8 +1622,15 @@ ast_expression::hir(exec_list *instructions,
             * FINISHME: array access limits be added to ir_dereference?
             */
            ir_variable *const v = array->whole_variable_referenced();
-           if ((v != NULL) && (unsigned(idx) > v->max_array_access))
+           if ((v != NULL) && (unsigned(idx) > v->max_array_access)) {
               v->max_array_access = idx;
+
+               /* Check whether this access will, as a side effect, implicitly
+                * cause the size of a built-in array to be too large.
+                */
+               if (check_builtin_array_max_size(v->name, idx+1, loc, state))
+                  error_emitted = true;
+            }
         }
       } else if (array->type->array_size() == 0) {
         _mesa_glsl_error(&loc, state, "unsized array index must be constant");
@@ -1748,18 +1842,23 @@ process_array_type(YYLTYPE *loc, const glsl_type *base, ast_node *array_size,
 {
    unsigned length = 0;
 
-   /* FINISHME: Reject delcarations of multidimensional arrays. */
+   /* From page 19 (page 25) of the GLSL 1.20 spec:
+    *
+    *     "Only one-dimensional arrays may be declared."
+    */
+   if (base->is_array()) {
+      _mesa_glsl_error(loc, state,
+                      "invalid array of `%s' (only one-dimensional arrays "
+                      "may be declared)",
+                      base->name);
+      return glsl_type::error_type;
+   }
 
    if (array_size != NULL) {
       exec_list dummy_instructions;
       ir_rvalue *const ir = array_size->hir(& dummy_instructions, state);
       YYLTYPE loc = array_size->get_location();
 
-      /* FINISHME: Verify that the grammar forbids side-effects in array
-       * FINISHME: sizes.   i.e., 'vec4 [x = 12] data'
-       */
-      assert(dummy_instructions.is_empty());
-
       if (ir != NULL) {
         if (!ir->type->is_integer()) {
            _mesa_glsl_error(& loc, state, "array size must be integer type");
@@ -1776,6 +1875,14 @@ process_array_type(YYLTYPE *loc, const glsl_type *base, ast_node *array_size,
            } else {
               assert(size->type == ir->type);
               length = size->value.u[0];
+
+               /* If the array size is const (and we've verified that
+                * it is) then no instructions should have been emitted
+                * when we converted it to HIR.  If they were emitted,
+                * then either the array size isn't const after all, or
+                * we are emitting unnecessary instructions.
+                */
+               assert(dummy_instructions.is_empty());
            }
         }
       }
@@ -1895,11 +2002,13 @@ apply_type_qualifier_to_variable(const struct ast_type_qualifier *qual,
    }
 
    if (qual->flags.q.flat)
-      var->interpolation = ir_var_flat;
+      var->interpolation = INTERP_QUALIFIER_FLAT;
    else if (qual->flags.q.noperspective)
-      var->interpolation = ir_var_noperspective;
+      var->interpolation = INTERP_QUALIFIER_NOPERSPECTIVE;
+   else if (qual->flags.q.smooth)
+      var->interpolation = INTERP_QUALIFIER_SMOOTH;
    else
-      var->interpolation = ir_var_smooth;
+      var->interpolation = INTERP_QUALIFIER_NONE;
 
    var->pixel_center_integer = qual->flags.q.pixel_center_integer;
    var->origin_upper_left = qual->flags.q.origin_upper_left;
@@ -1940,7 +2049,7 @@ apply_type_qualifier_to_variable(const struct ast_type_qualifier *qual,
         break;
 
       case fragment_shader:
-        if (!global_scope || (var->mode != ir_var_in)) {
+        if (!global_scope || (var->mode != ir_var_out)) {
            fail = true;
            string = "output";
         }
@@ -1995,6 +2104,7 @@ apply_type_qualifier_to_variable(const struct ast_type_qualifier *qual,
     * The following extension do not allow the deprecated keywords:
     *
     *    GL_AMD_conservative_depth
+    *    GL_ARB_conservative_depth
     *    GL_ARB_gpu_shader5
     *    GL_ARB_separate_shader_objects
     *    GL_ARB_tesselation_shader
@@ -2027,9 +2137,11 @@ apply_type_qualifier_to_variable(const struct ast_type_qualifier *qual,
       + qual->flags.q.depth_less
       + qual->flags.q.depth_unchanged;
    if (depth_layout_count > 0
-       && !state->AMD_conservative_depth_enable) {
+       && !state->AMD_conservative_depth_enable
+       && !state->ARB_conservative_depth_enable) {
        _mesa_glsl_error(loc, state,
-                        "extension GL_AMD_conservative_depth must be enabled "
+                        "extension GL_AMD_conservative_depth or "
+                        "GL_ARB_conservative_depth must be enabled "
                        "to use depth layout qualifiers");
    } else if (depth_layout_count > 0
               && strcmp(var->name, "gl_FragDepth") != 0) {
@@ -2052,10 +2164,6 @@ apply_type_qualifier_to_variable(const struct ast_type_qualifier *qual,
        var->depth_layout = ir_depth_layout_unchanged;
    else
        var->depth_layout = ir_depth_layout_none;
-
-   if (var->type->is_array() && state->language_version != 110) {
-      var->array_lvalue = true;
-   }
 }
 
 /**
@@ -2103,18 +2211,9 @@ get_variable_being_redeclared(ir_variable *var, ast_declaration *decl,
        * FINISHME: required or not.
        */
 
-      /* From page 54 (page 60 of the PDF) of the GLSL 1.20 spec:
-       *
-       *     "The size [of gl_TexCoord] can be at most
-       *     gl_MaxTextureCoords."
-       */
       const unsigned size = unsigned(var->type->array_size());
-      if ((strcmp("gl_TexCoord", var->name) == 0)
-         && (size > state->Const.MaxTextureCoords)) {
-        _mesa_glsl_error(& loc, state, "`gl_TexCoord' array size cannot "
-                         "be larger than gl_MaxTextureCoords (%u)\n",
-                         state->Const.MaxTextureCoords);
-      } else if ((size > 0) && (size <= earlier->max_array_access)) {
+      check_builtin_array_max_size(var->name, size, loc, state);
+      if ((size > 0) && (size <= earlier->max_array_access)) {
         _mesa_glsl_error(& loc, state, "array size must be > %u due to "
                          "previous access",
                          earlier->max_array_access);
@@ -2155,7 +2254,8 @@ get_variable_being_redeclared(ir_variable *var, ast_declaration *decl,
       earlier->interpolation = var->interpolation;
 
       /* Layout qualifiers for gl_FragDepth. */
-   } else if (state->AMD_conservative_depth_enable
+   } else if ((state->AMD_conservative_depth_enable ||
+               state->ARB_conservative_depth_enable)
              && strcmp(var->name, "gl_FragDepth") == 0
              && earlier->type == var->type
              && earlier->mode == var->mode) {
@@ -2279,12 +2379,16 @@ process_initializer(ir_variable *var, ast_declaration *decl,
       const glsl_type *initializer_type;
       if (!type->qualifier.flags.q.uniform) {
         result = do_assignment(initializer_instructions, state,
+                               NULL,
                                lhs, rhs, true,
                                type->get_location());
         initializer_type = result->type;
       } else
         initializer_type = rhs->type;
 
+      var->constant_initializer = rhs->constant_expression_value();
+      var->has_initializer = true;
+
       /* If the declared variable is an unsized array, it must inherrit
        * its full type from the initializer.  A declaration such as
        *
@@ -2389,14 +2493,32 @@ ast_declarator_list::hir(exec_list *instructions,
 
    decl_type = this->type->specifier->glsl_type(& type_name, state);
    if (this->declarations.is_empty()) {
-      /* The only valid case where the declaration list can be empty is when
-       * the declaration is setting the default precision of a built-in type
-       * (e.g., 'precision highp vec4;').
+      /* If there is no structure involved in the program text, there are two
+       * possible scenarios:
+       *
+       * - The program text contained something like 'vec4;'.  This is an
+       *   empty declaration.  It is valid but weird.  Emit a warning.
+       *
+       * - The program text contained something like 'S;' and 'S' is not the
+       *   name of a known structure type.  This is both invalid and weird.
+       *   Emit an error.
+       *
+       * Note that if decl_type is NULL and there is a structure involved,
+       * there must have been some sort of error with the structure.  In this
+       * case we assume that an error was already generated on this line of
+       * code for the structure.  There is no need to generate an additional,
+       * confusing error.
        */
-
-      if (decl_type != NULL) {
-      } else {
-           _mesa_glsl_error(& loc, state, "incomplete declaration");
+      assert(this->type->specifier->structure == NULL || decl_type != NULL
+            || state->error);
+      if (this->type->specifier->structure == NULL) {
+        if (decl_type != NULL) {
+           _mesa_glsl_warning(&loc, state, "empty declaration");
+        } else {
+           _mesa_glsl_error(&loc, state,
+                            "invalid type `%s' in empty declaration",
+                            type_name);
+        }
       }
    }
 
@@ -2424,6 +2546,8 @@ ast_declarator_list::hir(exec_list *instructions,
       if (decl->is_array) {
         var_type = process_array_type(&loc, decl_type, decl->array_size,
                                       state);
+        if (var_type->is_error())
+           continue;
       } else {
         var_type = decl_type;
       }
@@ -2576,7 +2700,7 @@ ast_declarator_list::hir(exec_list *instructions,
           && state->current_function == NULL
           && var->type->is_integer()
           && var->mode == ir_var_out
-          && var->interpolation != ir_var_flat) {
+          && var->interpolation != INTERP_QUALIFIER_FLAT) {
 
          _mesa_glsl_error(&loc, state, "If a vertex output is an integer, "
                           "then it must be qualified with 'flat'");
@@ -2696,6 +2820,17 @@ ast_declarator_list::hir(exec_list *instructions,
                                                       : "and integer");
       }
 
+      /* From page 17 (page 23 of the PDF) of the GLSL 1.20 spec:
+       *
+       *    "[Sampler types] can only be declared as function
+       *    parameters or uniform variables (see Section 4.3.5
+       *    "Uniform")".
+       */
+      if (var_type->contains_sampler() &&
+          !this->type->qualifier.flags.q.uniform) {
+         _mesa_glsl_error(&loc, state, "samplers must be declared uniform");
+      }
+
       /* Process the initializer and add its instructions to a temporary
        * list.  This list will be added to the instruction stream (below) after
        * the declaration is added.  This is done because in some cases (such as
@@ -2738,6 +2873,18 @@ ast_declarator_list::hir(exec_list *instructions,
            _mesa_glsl_error(& loc, state,
                             "identifier `%s' uses reserved `gl_' prefix",
                             decl->identifier);
+        else if (strstr(decl->identifier, "__")) {
+           /* From page 14 (page 20 of the PDF) of the GLSL 1.10
+            * spec:
+            *
+            *     "In addition, all identifiers containing two
+            *      consecutive underscores (__) are reserved as
+            *      possible future keywords."
+            */
+           _mesa_glsl_error(& loc, state,
+                            "identifier `%s' uses reserved `__' string",
+                            decl->identifier);
+        }
 
         /* Add the variable to the symbol table.  Note that the initializer's
          * IR was already processed earlier (though it hasn't been emitted
@@ -2842,7 +2989,7 @@ ast_parameter_declarator::hir(exec_list *instructions,
       type = process_array_type(&loc, type, this->array_size, state);
    }
 
-   if (type->array_size() == 0) {
+   if (!type->is_error() && type->array_size() == 0) {
       _mesa_glsl_error(&loc, state, "arrays passed as parameters must have "
                       "a declared size.");
       type = glsl_type::error_type;
@@ -2856,6 +3003,38 @@ ast_parameter_declarator::hir(exec_list *instructions,
     */
    apply_type_qualifier_to_variable(& this->type->qualifier, var, state, & loc);
 
+   /* From page 17 (page 23 of the PDF) of the GLSL 1.20 spec:
+    *
+    *    "Samplers cannot be treated as l-values; hence cannot be used
+    *    as out or inout function parameters, nor can they be assigned
+    *    into."
+    */
+   if ((var->mode == ir_var_inout || var->mode == ir_var_out)
+       && type->contains_sampler()) {
+      _mesa_glsl_error(&loc, state, "out and inout parameters cannot contain samplers");
+      type = glsl_type::error_type;
+   }
+
+   /* From page 39 (page 45 of the PDF) of the GLSL 1.10 spec:
+    *
+    *    "When calling a function, expressions that do not evaluate to
+    *     l-values cannot be passed to parameters declared as out or inout."
+    *
+    * From page 32 (page 38 of the PDF) of the GLSL 1.10 spec:
+    *
+    *    "Other binary or unary expressions, non-dereferenced arrays,
+    *     function names, swizzles with repeated fields, and constants
+    *     cannot be l-values."
+    *
+    * So for GLSL 1.10, passing an array as an out or inout parameter is not
+    * allowed.  This restriction is removed in GLSL 1.20, and in GLSL ES.
+    */
+   if ((var->mode == ir_var_inout || var->mode == ir_var_out)
+       && type->is_array() && state->language_version == 110) {
+      _mesa_glsl_error(&loc, state, "Arrays cannot be out or inout parameters in GLSL 1.10");
+      type = glsl_type::error_type;
+   }
+
    instructions->push_tail(var);
 
    /* Parameter declarations do not have r-values.
@@ -2893,23 +3072,16 @@ ast_parameter_declarator::parameters_to_hir(exec_list *ast_parameters,
 
 
 void
-emit_function(_mesa_glsl_parse_state *state, exec_list *instructions,
-             ir_function *f)
+emit_function(_mesa_glsl_parse_state *state, ir_function *f)
 {
-   /* Emit the new function header */
-   if (state->current_function == NULL) {
-      instructions->push_tail(f);
-   } else {
-      /* IR invariants disallow function declarations or definitions nested
-       * within other function definitions.  Insert the new ir_function
-       * block in the instruction sequence before the ir_function block
-       * containing the current ir_function_signature.
-       */
-      ir_function *const curr =
-        const_cast<ir_function *>(state->current_function->function());
-
-      curr->insert_before(f);
-   }
+   /* IR invariants disallow function declarations or definitions
+    * nested within other function definitions.  But there is no
+    * requirement about the relative order of function declarations
+    * and definitions with respect to one another.  So simply insert
+    * the new ir_function block at the end of the toplevel instruction
+    * list.
+    */
+   state->toplevel_ir->push_tail(f);
 }
 
 
@@ -2924,6 +3096,12 @@ ast_function::hir(exec_list *instructions,
 
    const char *const name = identifier;
 
+   /* New functions are always added to the top-level IR instruction stream,
+    * so this instruction list pointer is ignored.  See also emit_function
+    * (called below).
+    */
+   (void) instructions;
+
    /* From page 21 (page 27 of the PDF) of the GLSL 1.20 spec,
     *
     *   "Function declarations (prototypes) cannot occur inside of functions;
@@ -2984,6 +3162,18 @@ ast_function::hir(exec_list *instructions,
                       "function `%s' return type has qualifiers", name);
    }
 
+   /* From page 17 (page 23 of the PDF) of the GLSL 1.20 spec:
+    *
+    *    "[Sampler types] can only be declared as function parameters
+    *    or uniform variables (see Section 4.3.5 "Uniform")".
+    */
+   if (return_type->contains_sampler()) {
+      YYLTYPE loc = this->get_location();
+      _mesa_glsl_error(&loc, state,
+                       "function `%s' return type can't contain a sampler",
+                       name);
+   }
+
    /* Verify that this function's signature either doesn't match a previously
     * seen signature for a function with the same name, or, if a match is found,
     * that the previously seen signature does not have an associated definition.
@@ -3024,7 +3214,7 @@ ast_function::hir(exec_list *instructions,
         return NULL;
       }
 
-      emit_function(state, instructions, f);
+      emit_function(state, f);
    }
 
    /* Verify the return type of main() */
@@ -3184,34 +3374,49 @@ ast_jump_statement::hir(exec_list *instructions,
 
    case ast_break:
    case ast_continue:
-      /* FINISHME: Handle switch-statements.  They cannot contain 'continue',
-       * FINISHME: and they use a different IR instruction for 'break'.
-       */
-      /* FINISHME: Correctly handle the nesting.  If a switch-statement is
-       * FINISHME: inside a loop, a 'continue' is valid and will bind to the
-       * FINISHME: loop.
-       */
-      if (state->loop_or_switch_nesting == NULL) {
+      if (mode == ast_continue &&
+         state->loop_nesting_ast == NULL) {
         YYLTYPE loc = this->get_location();
 
         _mesa_glsl_error(& loc, state,
-                         "`%s' may only appear in a loop",
-                         (mode == ast_break) ? "break" : "continue");
-      } else {
-        ir_loop *const loop = state->loop_or_switch_nesting->as_loop();
+                         "continue may only appear in a loop");
+      } else if (mode == ast_break &&
+                state->loop_nesting_ast == NULL &&
+                state->switch_nesting_ast == NULL) {
+        YYLTYPE loc = this->get_location();
 
-        /* Inline the for loop expression again, since we don't know
-         * where near the end of the loop body the normal copy of it
+        _mesa_glsl_error(& loc, state,
+                         "break may only appear in a loop or a switch");
+      } else {
+        /* For a loop, inline the for loop expression again,
+         * since we don't know where near the end of
+         * the loop body the normal copy of it
          * is going to be placed.
          */
-        if (mode == ast_continue &&
-            state->loop_or_switch_nesting_ast->rest_expression) {
-           state->loop_or_switch_nesting_ast->rest_expression->hir(instructions,
-                                                                   state);
+        if (state->loop_nesting_ast != NULL &&
+            mode == ast_continue &&
+            state->loop_nesting_ast->rest_expression) {
+           state->loop_nesting_ast->rest_expression->hir(instructions,
+                                                         state);
         }
 
-        if (loop != NULL) {
-           ir_loop_jump *const jump =
+        if (state->is_switch_innermost &&
+            mode == ast_break) {
+           /* Force break out of switch by setting is_break switch state.
+            */
+           ir_variable *const is_break_var = state->is_break_var;
+           ir_dereference_variable *const deref_is_break_var =
+              new(ctx) ir_dereference_variable(is_break_var);
+           ir_constant *const true_val = new(ctx) ir_constant(true);
+           ir_assignment *const set_break_var =
+              new(ctx) ir_assignment(deref_is_break_var,
+                                     true_val,
+                                     NULL);
+           
+           instructions->push_tail(set_break_var);
+        }
+        else {
+           ir_loop_jump *const jump = 
               new(ctx) ir_loop_jump((mode == ast_break)
                                     ? ir_loop_jump::jump_break
                                     : ir_loop_jump::jump_continue);
@@ -3274,6 +3479,243 @@ ast_selection_statement::hir(exec_list *instructions,
 }
 
 
+ir_rvalue *
+ast_switch_statement::hir(exec_list *instructions,
+                         struct _mesa_glsl_parse_state *state)
+{
+   void *ctx = state;
+
+   ir_rvalue *const test_expression =
+      this->test_expression->hir(instructions, state);
+
+   /* From page 66 (page 55 of the PDF) of the GLSL 1.50 spec:
+    *
+    *    "The type of init-expression in a switch statement must be a 
+    *     scalar integer." 
+    *
+    * The checks are separated so that higher quality diagnostics can be
+    * generated for cases where the rule is violated.
+    */
+   if (!test_expression->type->is_integer()) {
+      YYLTYPE loc = this->test_expression->get_location();
+
+      _mesa_glsl_error(& loc,
+                      state,
+                      "switch-statement expression must be scalar "
+                      "integer");
+   }
+
+   /* Track the switch-statement nesting in a stack-like manner.
+    */
+   ir_variable *saved_test_var = state->test_var;
+   ir_variable *saved_is_fallthru_var = state->is_fallthru_var;
+   
+   bool save_is_switch_innermost = state->is_switch_innermost;
+   ast_switch_statement *saved_nesting_ast = state->switch_nesting_ast;
+
+   state->is_switch_innermost = true;
+   state->switch_nesting_ast = this;
+
+   /* Initalize is_fallthru state to false.
+    */
+   ir_rvalue *const is_fallthru_val = new (ctx) ir_constant(false);
+   state->is_fallthru_var = new(ctx) ir_variable(glsl_type::bool_type,
+                                               "switch_is_fallthru_tmp",
+                                               ir_var_temporary);
+   instructions->push_tail(state->is_fallthru_var);
+
+   ir_dereference_variable *deref_is_fallthru_var =
+      new(ctx) ir_dereference_variable(state->is_fallthru_var);
+   instructions->push_tail(new(ctx) ir_assignment(deref_is_fallthru_var,
+                                                 is_fallthru_val,
+                                                 NULL));
+
+   /* Initalize is_break state to false.
+    */
+   ir_rvalue *const is_break_val = new (ctx) ir_constant(false);
+   state->is_break_var = new(ctx) ir_variable(glsl_type::bool_type,
+                                             "switch_is_break_tmp",
+                                             ir_var_temporary);
+   instructions->push_tail(state->is_break_var);
+
+   ir_dereference_variable *deref_is_break_var =
+      new(ctx) ir_dereference_variable(state->is_break_var);
+   instructions->push_tail(new(ctx) ir_assignment(deref_is_break_var,
+                                                 is_break_val,
+                                                 NULL));
+
+   /* Cache test expression.
+    */
+   test_to_hir(instructions, state);
+   
+   /* Emit code for body of switch stmt.
+    */
+   body->hir(instructions, state);
+
+   /* Restore previous nesting before returning.
+    */
+   state->switch_nesting_ast = saved_nesting_ast;
+   state->is_switch_innermost = save_is_switch_innermost;
+
+   state->test_var = saved_test_var;
+   state->is_fallthru_var = saved_is_fallthru_var;
+
+   /* Switch statements do not have r-values.
+    */
+   return NULL;
+}
+
+
+void
+ast_switch_statement::test_to_hir(exec_list *instructions,
+                                 struct _mesa_glsl_parse_state *state)
+{
+   void *ctx = state;
+
+   /* Cache value of test expression.
+    */
+   ir_rvalue *const test_val =
+      test_expression->hir(instructions,
+                          state);
+
+   state->test_var = new(ctx) ir_variable(glsl_type::int_type,
+                                         "switch_test_tmp",
+                                         ir_var_temporary);
+   ir_dereference_variable *deref_test_var =
+      new(ctx) ir_dereference_variable(state->test_var);
+
+   instructions->push_tail(state->test_var);
+   instructions->push_tail(new(ctx) ir_assignment(deref_test_var,
+                                                 test_val,
+                                                 NULL));
+}
+
+
+ir_rvalue *
+ast_switch_body::hir(exec_list *instructions,
+                    struct _mesa_glsl_parse_state *state)
+{
+   if (stmts != NULL)
+      stmts->hir(instructions, state);
+      
+   /* Switch bodies do not have r-values.
+    */
+   return NULL;
+}
+
+
+ir_rvalue *
+ast_case_statement_list::hir(exec_list *instructions,
+                            struct _mesa_glsl_parse_state *state)
+{
+   foreach_list_typed (ast_case_statement, case_stmt, link, & this->cases)
+      case_stmt->hir(instructions, state);
+         
+   /* Case statements do not have r-values.
+    */
+   return NULL;
+}
+
+
+ir_rvalue *
+ast_case_statement::hir(exec_list *instructions,
+                       struct _mesa_glsl_parse_state *state)
+{
+   labels->hir(instructions, state);
+   
+   /* Conditionally set fallthru state based on break state.
+    */
+   ir_constant *const false_val = new(state) ir_constant(false);
+   ir_dereference_variable *const deref_is_fallthru_var =
+      new(state) ir_dereference_variable(state->is_fallthru_var);
+   ir_dereference_variable *const deref_is_break_var =
+      new(state) ir_dereference_variable(state->is_break_var);
+   ir_assignment *const reset_fallthru_on_break =
+      new(state) ir_assignment(deref_is_fallthru_var,
+                              false_val,
+                              deref_is_break_var);
+   instructions->push_tail(reset_fallthru_on_break);
+
+   /* Guard case statements depending on fallthru state.
+    */
+   ir_dereference_variable *const deref_fallthru_guard =
+      new(state) ir_dereference_variable(state->is_fallthru_var);
+   ir_if *const test_fallthru = new(state) ir_if(deref_fallthru_guard);
+   
+   foreach_list_typed (ast_node, stmt, link, & this->stmts)
+      stmt->hir(& test_fallthru->then_instructions, state);
+
+   instructions->push_tail(test_fallthru);
+         
+   /* Case statements do not have r-values.
+    */
+   return NULL;
+}
+
+
+ir_rvalue *
+ast_case_label_list::hir(exec_list *instructions,
+                        struct _mesa_glsl_parse_state *state)
+{
+   foreach_list_typed (ast_case_label, label, link, & this->labels)
+      label->hir(instructions, state);
+         
+   /* Case labels do not have r-values.
+    */
+   return NULL;
+}
+
+
+ir_rvalue *
+ast_case_label::hir(exec_list *instructions,
+                   struct _mesa_glsl_parse_state *state)
+{
+   void *ctx = state;
+
+   ir_dereference_variable *deref_fallthru_var =
+      new(ctx) ir_dereference_variable(state->is_fallthru_var);
+   
+   ir_rvalue *const true_val = new(ctx) ir_constant(true);
+
+   /* If not default case, ...
+    */
+   if (this->test_value != NULL) {
+      /* Conditionally set fallthru state based on
+       * comparison of cached test expression value to case label.
+       */
+      ir_rvalue *const test_val = this->test_value->hir(instructions, state);
+
+      ir_dereference_variable *deref_test_var =
+        new(ctx) ir_dereference_variable(state->test_var);
+
+      ir_rvalue *const test_cond = new(ctx) ir_expression(ir_binop_all_equal,
+                                                         glsl_type::bool_type,
+                                                         test_val,
+                                                         deref_test_var);
+
+      ir_assignment *set_fallthru_on_test =
+        new(ctx) ir_assignment(deref_fallthru_var,
+                               true_val,
+                               test_cond);
+   
+      instructions->push_tail(set_fallthru_on_test);
+   } else { /* default case */
+      /* Set falltrhu state.
+       */
+      ir_assignment *set_fallthru =
+        new(ctx) ir_assignment(deref_fallthru_var,
+                               true_val,
+                               NULL);
+   
+      instructions->push_tail(set_fallthru);
+   }
+   
+   /* Case statements do not have r-values.
+    */
+   return NULL;
+}
+
+
 void
 ast_iteration_statement::condition_to_hir(ir_loop *stmt,
                                          struct _mesa_glsl_parse_state *state)
@@ -3327,13 +3769,17 @@ ast_iteration_statement::hir(exec_list *instructions,
    ir_loop *const stmt = new(ctx) ir_loop();
    instructions->push_tail(stmt);
 
-   /* Track the current loop and / or switch-statement nesting.
+   /* Track the current loop nesting.
     */
-   ir_instruction *const nesting = state->loop_or_switch_nesting;
-   ast_iteration_statement *nesting_ast = state->loop_or_switch_nesting_ast;
+   ast_iteration_statement *nesting_ast = state->loop_nesting_ast;
+
+   state->loop_nesting_ast = this;
 
-   state->loop_or_switch_nesting = stmt;
-   state->loop_or_switch_nesting_ast = this;
+   /* Likewise, indicate that following code is closest to a loop,
+    * NOT closest to a switch.
+    */
+   bool saved_is_switch_innermost = state->is_switch_innermost;
+   state->is_switch_innermost = false;
 
    if (mode != ast_do_while)
       condition_to_hir(stmt, state);
@@ -3352,8 +3798,8 @@ ast_iteration_statement::hir(exec_list *instructions,
 
    /* Restore previous nesting before returning.
     */
-   state->loop_or_switch_nesting = nesting;
-   state->loop_or_switch_nesting_ast = nesting_ast;
+   state->loop_nesting_ast = nesting_ast;
+   state->is_switch_innermost = saved_is_switch_innermost;
 
    /* Loops do not have r-values.
     */