Merge pull request #824 from larsclausen/class-lifetime

Fix variable initialization in class methods

elab_scope.cc

@@ -517,7 +517,14 @@ static void elaborate_scope_class(Design*des, NetScope*scope, PClass*pclass)
 
 	    hname_t use_name (cur->first);
 	    NetScope*method_scope = new NetScope(class_scope, use_name, NetScope::TASK);
+
 	      // Task methods are always automatic...
+	    if (!cur->second->is_auto()) {
+		  cerr << "error: Lifetime of method `"
+		       << scope_path(method_scope)
+		       << "` must not be static" << endl;
+		  des->errors += 1;
+	    }
 	    method_scope->is_auto(true);
 	    method_scope->set_line(cur->second);
 	    method_scope->add_imports(&cur->second->explicit_imports);
@@ -536,7 +543,14 @@ static void elaborate_scope_class(Design*des, NetScope*scope, PClass*pclass)
 
 	    hname_t use_name (cur->first);
 	    NetScope*method_scope = new NetScope(class_scope, use_name, NetScope::FUNC);
+
 	      // Function methods are always automatic...
+	    if (!cur->second->is_auto()) {
+		  cerr << "error: Lifetime of method `"
+		       << scope_path(method_scope)
+		       << "` must not be static" << endl;
+		  des->errors += 1;
+	    }
 	    method_scope->is_auto(true);
 	    method_scope->set_line(cur->second);
 	    method_scope->add_imports(&cur->second->explicit_imports);

ivtest/ivltests/sv_class_method_lt_static1.v

@@ -0,0 +1,18 @@
+// Check that specifing static lifetime for a class method taks results in an
+// error.
+
+module test;
+
+  class C;
+    // This should fail, all class methods have automatic lifetime
+    task static t(int x);
+      int y;
+      y = 2 * x;
+    endtask
+  endclass
+
+  initial begin
+    $display("FAILED");
+  end
+
+endmodule

ivtest/ivltests/sv_class_method_lt_static2.v

@@ -0,0 +1,19 @@
+// Check that specifing static lifetime for a class method function results in
+// an error.
+
+module test;
+
+  class C;
+    // This should fail, all class methods have automatic lifetime
+    function static int t(int x);
+      int y;
+      y = 2 * x;
+      return y;
+    endfunction
+  endclass
+
+  initial begin
+    $display("FAILED");
+  end
+
+endmodule

ivtest/ivltests/sv_class_method_var_init.v

@@ -0,0 +1,25 @@
+// Check that variable initialization as part of the declaration works as
+// expected in class methods.
+
+module test;
+  class C;
+    task t(bit check);
+      int x = 10; // The initialization should happen on each invocation
+      if (check) begin
+        if (x === 10) begin
+          $display("PASSED");
+        end else begin
+          $display("FAILED");
+        end
+      end
+      x = 20;
+    endtask
+  endclass
+
+  initial begin
+    C c;
+    c = new;
+    c.t(1'b0);
+    c.t(1'b1);
+  end
+endmodule

ivtest/regress-sv.list

@@ -565,8 +565,11 @@ sv_class_in_module_decl	normal,-g2009		ivltests
 sv_class_method_call_void	normal,-g2009	ivltests
 sv_class_method_default1 normal,-g2009		ivltests
 sv_class_method_default2 normal,-g2009		ivltests
+sv_class_method_lt_static1	CE,-g2009	ivltests
+sv_class_method_lt_static2	CE,-g2009	ivltests
 sv_class_method_signed1	normal,-g2009		ivltests
 sv_class_method_signed2	normal,-g2009		ivltests
+sv_class_method_var_init	normal,-g2009	ivltests
 sv_class_property_signed1	normal,-g2009	ivltests
 sv_class_property_signed2	normal,-g2009	ivltests
 sv_class_property_signed3	normal,-g2009	ivltests

ivtest/regress-vlog95.list

@@ -422,6 +422,7 @@ sv_class_method_default1 CE,-g2009		ivltests
 sv_class_method_default2 CE,-g2009		ivltests
 sv_class_method_signed1	CE,-g2009,-pallowsigned=1	ivltests
 sv_class_method_signed2	CE,-g2009,-pallowsigned=1	ivltests
+sv_class_method_var_init	CE,-g2009,-pallowsigned=1	ivltests
 sv_class_property_signed1	CE,-g2009,-pallowsigned=1	ivltests
 sv_class_property_signed2	CE,-g2009,-pallowsigned=1	ivltests
 sv_class_property_signed3	CE,-g2009,-pallowsigned=1	ivltests

parse.y

@@ -796,12 +796,22 @@ block_identifier_opt /* */
 
 class_declaration /* IEEE1800-2005: A.1.2 */
   : K_virtual_opt K_class lifetime_opt identifier_name class_declaration_extends_opt ';'
-      {
+      { /* Up to 1800-2017 the grammar in the LRM allowed an optional lifetime
+	 * qualifier for class declarations. But the LRM never specified what
+	 * this qualifier should do. Starting with 1800-2023 the qualifier has
+	 * been removed from the grammar. Allow it for backwards compatibility,
+	 * but print a warning.
+	 */
+	if ($3 != LexicalScope::INHERITED) {
+	      cerr << @1 << ": warning: Class lifetime qualifier is deprecated "
+			    "and has no effect." << endl;
+	      warn_count += 1;
+	}
 	perm_string name = lex_strings.make($4);
 	class_type_t *class_type= new class_type_t(name);
 	FILE_NAME(class_type, @4);
 	pform_set_typedef(@4, name, class_type, nullptr);
-	pform_start_class_declaration(@2, class_type, $5.type, $5.exprs, $3, $1);
+	pform_start_class_declaration(@2, class_type, $5.type, $5.exprs, $1);
       }
     class_items_opt K_endclass
       { // Process a class.

pform.cc

@@ -602,11 +602,10 @@ static void pform_set_scope_timescale(PScope*scope, const PScope*parent)
       scope->time_prec_is_default = parent->time_prec_is_default;
 }
 
-PClass* pform_push_class_scope(const struct vlltype&loc, perm_string name,
-			       LexicalScope::lifetime_t lifetime)
+PClass* pform_push_class_scope(const struct vlltype&loc, perm_string name)
 {
       PClass*class_scope = new PClass(name, lexical_scope);
-      class_scope->default_lifetime = find_lifetime(lifetime);
+      class_scope->default_lifetime = LexicalScope::AUTOMATIC;
       FILE_NAME(class_scope, loc);
 
       PScopeExtra*scopex = find_nearest_scopex(lexical_scope);

pform.h

@@ -173,7 +173,6 @@ extern void pform_start_class_declaration(const struct vlltype&loc,
 					  class_type_t*type,
 					  data_type_t*base_type,
 					  std::list<PExpr*>*base_exprs,
-					  LexicalScope::lifetime_t lifetime,
 					  bool virtual_class);
 extern void pform_class_property(const struct vlltype&loc,
 				 property_qualifier_t pq,
@@ -241,8 +240,7 @@ extern void pform_pop_scope();
  */
 extern LexicalScope* pform_peek_scope();
 
-extern PClass* pform_push_class_scope(const struct vlltype&loc, perm_string name,
-				      LexicalScope::lifetime_t lifetime);
+extern PClass* pform_push_class_scope(const struct vlltype&loc, perm_string name);
 
 extern PFunction*pform_push_constructor_scope(const struct vlltype&loc);
 

pform_pclass.cc

@@ -43,10 +43,9 @@ void pform_start_class_declaration(const struct vlltype&loc,
 				   class_type_t*type,
 				   data_type_t*base_type,
 				   list<PExpr*>*base_exprs,
-				   LexicalScope::lifetime_t lifetime,
 				   bool virtual_class)
 {
-      PClass*class_scope = pform_push_class_scope(loc, type->name, lifetime);
+      PClass*class_scope = pform_push_class_scope(loc, type->name);
       class_scope->type = type;
       assert(pform_cur_class == 0);
       pform_cur_class = class_scope;