Merge pull request #863 from larsclausen/export

Add support for package export

PPackage.h

@@ -24,6 +24,7 @@
 # include  "LineInfo.h"
 # include  "StringHeap.h"
 # include  <iostream>
+# include  <vector>
 
 /*
  * SystemVerilog supports class declarations with their own lexical
@@ -42,6 +43,13 @@ class PPackage : public PScopeExtra, public LineInfo {
       bool elaborate(Design*des, NetScope*scope) const;
 
       void pform_dump(std::ostream&out) const;
+
+      struct export_t {
+	    PPackage *pkg;
+	    perm_string name;
+      };
+
+      std::vector<export_t> exports;
 };
 
 #endif /* IVL_PPackage_H */

PScope.h

@@ -25,6 +25,7 @@
 # include  "ivl_target.h"
 # include  <map>
 # include  <set>
+# include  <unordered_set>
 # include  <vector>
 
 class PEvent;
@@ -67,9 +68,14 @@ class LexicalScope {
 	// Symbols that are defined or declared in this scope.
       std::map<perm_string,PNamedItem*>local_symbols;
 
-	// Symbols that are explicitly imported. Bind the imported name
-	// to the package from which the name is imported.
+	// Symbols that are explicitly imported. This contains the package where
+	// the symbol has been decelared. When using exports, this might not be
+	// the same as the package where it has been imported from.
       std::map<perm_string,PPackage*>explicit_imports;
+        // Symbols that are explicitly imported. This contains the set of
+	// packages from which the symbol has been imported. When using exports
+	// the same identifier can be imported via multiple packages.
+      std::map<perm_string,std::unordered_set<PPackage*>> explicit_imports_from;
 
 	// Packages that are wildcard imported. When identifiers from
 	// these packages are referenced, they will be added to the

ivtest/ivltests/sv_export1.v

@@ -0,0 +1,25 @@
+// Check that it is possible to explicitly export an identifier and import it
+// from another scope.
+
+package P1;
+  integer x = 123;
+endpackage
+
+package P2;
+  import P1::x;
+  export P1::x;
+endpackage
+
+module test;
+
+  import P2::x;
+
+  initial begin
+    if (x == 123) begin
+      $display("PASSED");
+    end else begin
+      $display("FAILED");
+    end
+  end
+
+endmodule

ivtest/ivltests/sv_export2.v

@@ -0,0 +1,25 @@
+// Check that it is possible use package wildcard export an identifier and
+// import it from another scope.
+
+package P1;
+  integer x = 123;
+endpackage
+
+package P2;
+  import P1::x;
+  export P1::*;
+endpackage
+
+module test;
+
+  import P2::x;
+
+  initial begin
+    if (x == 123) begin
+      $display("PASSED");
+    end else begin
+      $display("FAILED");
+    end
+  end
+
+endmodule

ivtest/ivltests/sv_export3.v

@@ -0,0 +1,25 @@
+// Check that it is possible use full wildcard export an identifier and import
+// it from another scope.
+
+package P1;
+  integer x = 123;
+endpackage
+
+package P2;
+  import P1::x;
+  export *::*;
+endpackage
+
+module test;
+
+  import P2::x;
+
+  initial begin
+    if (x == 123) begin
+      $display("PASSED");
+    end else begin
+      $display("FAILED");
+    end
+  end
+
+endmodule

ivtest/ivltests/sv_export4.v

@@ -0,0 +1,25 @@
+// Check that it is possible to export an implicitly imported identifier and
+// import it again from another scope.
+
+package P1;
+  integer x = 123;
+endpackage
+
+package P2;
+  import P1::*;
+  export P1::x;
+endpackage
+
+module test;
+
+  import P2::x;
+
+  initial begin
+    if (x == 123) begin
+      $display("PASSED");
+    end else begin
+      $display("FAILED");
+    end
+  end
+
+endmodule

ivtest/ivltests/sv_export5.v

@@ -0,0 +1,26 @@
+// Check that implicitly imported identifiers can be exported through a package
+// wildcard export.
+
+package P1;
+  integer x = 123;
+endpackage
+
+package P2;
+  import P1::*;
+  export P1::*;
+  integer y = x; // Creates an import for P1::x
+endpackage
+
+module test;
+
+  import P2::x;
+
+  initial begin
+    if (x == 123) begin
+      $display("PASSED");
+    end else begin
+      $display("FAILED");
+    end
+  end
+
+endmodule

ivtest/ivltests/sv_export6.v

@@ -0,0 +1,28 @@
+// Check that it is possible to implicitly import the same identifier through
+// multiple paths without causing a conflict.
+
+package P1;
+  integer x = 123;
+endpackage
+
+package P2;
+  import P1::x;
+  export P1::x;
+endpackage
+
+module test;
+
+  // P1::x is visible through either of the imports below. This should not
+  // create a conflict since it is the same identifier.
+  import P1::*;
+  import P2::*;
+
+  initial begin
+    if (x == 123) begin
+      $display("PASSED");
+    end else begin
+      $display("FAILED");
+    end
+  end
+
+endmodule

ivtest/ivltests/sv_export_fail1.v

@@ -0,0 +1,22 @@
+// Check that it is an error to export an identifier from a package from which
+// it has not been imported from.
+
+package P1;
+  integer x;
+endpackage
+
+package P2;
+  import P1::x;
+  export P1::x;
+endpackage
+
+package P3;
+  import P1::x;
+  export P2::x; // This should fail, even though P2::x is the same as P1::x
+endpackage
+
+module test;
+  initial begin
+    $display("FAILED");
+  end
+endmodule

ivtest/ivltests/sv_export_fail2.v

@@ -0,0 +1,17 @@
+// Check that it is an error to export an identifier that has not been imported.
+
+package P1;
+  integer x;
+  integer y;
+endpackage
+
+package P2;
+  import P1::x;
+  export P1::y; // Should fail, P1::y has not been imported.
+endpackage
+
+module test;
+  initial begin
+    $display("FAILED");
+  end
+endmodule

ivtest/ivltests/sv_export_fail3.v

@@ -0,0 +1,23 @@
+// Check that an identifier importable through a wildcard import is not exported
+// through a wildcard export if the identifier has not been referenced in
+// package.
+
+package P1;
+  integer x = 123;
+endpackage
+
+package P2;
+  import P1::*;
+  export *::*;
+endpackage
+
+module test;
+
+  import P2::x; // This should fail, P1::x is not referenced in P2 and hence not
+                // exportable through P2
+
+  initial begin
+    $display("FAILED");
+  end
+
+endmodule

ivtest/ivltests/sv_export_fail4.v

@@ -0,0 +1,23 @@
+// Check that it is an error to export an identifier that is importable through
+// a wildcard import if it creates a conflict with a local identifier.
+
+package P1;
+  integer x = 123;
+endpackage
+
+package P2;
+  import P1::*;
+  integer x = 456;
+  export P1::x; // This should fail, P1::x can not be imported into this scope
+                // since the name already exists.
+endpackage
+
+module test;
+
+  import P2::x;
+
+  initial begin
+    $display("FAILED");
+  end
+
+endmodule

ivtest/ivltests/sv_export_fail5.v

@@ -0,0 +1,25 @@
+// Check that it is an error to export an identifier that is importable through
+// a wildcard import if it creates a conflict with a local identifier, even if
+// the local identifier is declared after the export.
+
+package P1;
+  integer x = 123;
+endpackage
+
+package P2;
+  import P1::*;
+  export P1::x; // This should fail, P1::x can not be imported into this scope
+                // since the there is a local symbol with the same name. Even if
+                // it is declared after the export.
+  integer x = 456;
+endpackage
+
+module test;
+
+  import P2::x;
+
+  initial begin
+    $display("FAILED");
+  end
+
+endmodule

ivtest/ivltests/sv_export_fail6.v

@@ -0,0 +1,22 @@
+// Check that an error is reported if trying to export an identifier that is
+// declared outside of a package
+
+integer x = 123;
+
+package P1;
+endpackage
+
+package P2;
+  import P1::*;
+  export P1::x; // This should fail. x is visible in P1, but not declared in P1
+endpackage
+
+module test;
+
+  import P2::x;
+
+  initial begin
+    $display("FAILED");
+  end
+
+endmodule

ivtest/regress-sv.list

@@ -668,6 +668,18 @@ sv_end_labels		normal,-g2009		ivltests
 sv_end_labels_bad	CE,-g2009		ivltests gold=sv_end_labels_bad.gold
 sv_end_labels_unnamed	CE,-g2009		ivltests gold=sv_end_labels_unnamed.gold
 sv_enum1		normal,-g2009		ivltests
+sv_export1		normal,-g2009		ivltests
+sv_export2		normal,-g2009		ivltests
+sv_export3		normal,-g2009		ivltests
+sv_export4		normal,-g2009		ivltests
+sv_export5		normal,-g2009		ivltests
+sv_export6		normal,-g2009		ivltests
+sv_export_fail1		CE,-g2009		ivltests
+sv_export_fail2		CE,-g2009		ivltests
+sv_export_fail3		CE,-g2009		ivltests
+sv_export_fail4		CE,-g2009		ivltests
+sv_export_fail5		CE,-g2009		ivltests
+sv_export_fail6		CE,-g2009		ivltests
 sv_for_variable		normal,-g2009		ivltests
 sv_foreach1		normal,-g2009		ivltests
 sv_foreach2		normal,-g2009		ivltests

parse.y

@@ -2053,6 +2053,30 @@ package_import_item_list
   | package_import_item
   ;
 
+package_export_declaration /* IEEE1800-2017 A.2.1.3 */
+  : K_export package_export_item_list ';'
+  | K_export '*' K_SCOPE_RES '*' ';' { pform_package_export(@$, nullptr, nullptr); }
+  ;
+
+package_export_item
+  : PACKAGE_IDENTIFIER K_SCOPE_RES IDENTIFIER
+      { pform_package_export(@2, $1, $3);
+	delete[] $3;
+      }
+  | PACKAGE_IDENTIFIER K_SCOPE_RES TYPE_IDENTIFIER
+      { pform_package_export(@2, $1, $3.text);
+	delete[] $3.text;
+      }
+  | PACKAGE_IDENTIFIER K_SCOPE_RES '*'
+      { pform_package_export(@2, $1, nullptr);
+      }
+  ;
+
+package_export_item_list
+  : package_export_item_list ',' package_export_item
+  | package_export_item
+  ;
+
 package_item /* IEEE1800-2005 A.1.10 */
   : timeunits_declaration
   | parameter_declaration
@@ -2061,6 +2085,7 @@ package_item /* IEEE1800-2005 A.1.10 */
   | task_declaration
   | data_declaration
   | class_declaration
+  | package_export_declaration
   ;
 
 package_item_list

pform.cc

@@ -472,41 +472,6 @@ static void add_local_symbol(LexicalScope*scope, perm_string name, PNamedItem*it
       scope->local_symbols[name] = item;
 }
 
-static PPackage*find_potential_import(const struct vlltype&loc, LexicalScope*scope,
-				      perm_string name, bool tf_call, bool make_explicit)
-{
-      assert(scope);
-
-      PPackage*found_pkg = 0;
-      for (list<PPackage*>::const_iterator cur_pkg = scope->potential_imports.begin();
-	      cur_pkg != scope->potential_imports.end(); ++cur_pkg) {
-	    PPackage*search_pkg = *cur_pkg;
-	    map<perm_string,PNamedItem*>::const_iterator cur_sym
-		= search_pkg->local_symbols.find(name);
-	    if (cur_sym != search_pkg->local_symbols.end()) {
-		  if (found_pkg && make_explicit) {
-			cerr << loc.get_fileline() << ": error: "
-				"Ambiguous use of '" << name << "'. "
-				"It is exported by both '"
-			      << found_pkg->pscope_name()
-			      << "' and by '"
-			      << search_pkg->pscope_name()
-			      << "'." << endl;
-			error_count += 1;
-		  } else {
-			found_pkg = search_pkg;
-			if (make_explicit) {
-                              if (tf_call)
-			            scope->possible_imports[name] = found_pkg;
-                              else
-			            scope->explicit_imports[name] = found_pkg;
-                        }
-		  }
-	    }
-      }
-      return found_pkg;
-}
-
 static void check_potential_imports(const struct vlltype&loc, perm_string name, bool tf_call)
 {
       LexicalScope*scope = lexical_scope;
@@ -515,7 +480,7 @@ static void check_potential_imports(const struct vlltype&loc, perm_string name,
 		  return;
 	    if (scope->explicit_imports.find(name) != scope->explicit_imports.end())
 		  return;
-	    if (find_potential_import(loc, scope, name, tf_call, true))
+	    if (pform_find_potential_import(loc, scope, name, tf_call, true))
 		  return;
 
 	    scope = scope->parent_scope();
@@ -938,7 +903,7 @@ typedef_t* pform_test_type_identifier(const struct vlltype&loc, const char*txt)
 	    if (cur != cur_scope->typedefs.end())
 		  return cur->second;
 
-            PPackage*pkg = find_potential_import(loc, cur_scope, name, false, false);
+            PPackage*pkg = pform_find_potential_import(loc, cur_scope, name, false, false);
             if (pkg) {
 	          cur = pkg->typedefs.find(name);
 	          if (cur != pkg->typedefs.end())

pform.h

@@ -203,6 +203,12 @@ extern void pform_start_package_declaration(const struct vlltype&loc,
 extern void pform_end_package_declaration(const struct vlltype&loc);
 extern void pform_package_import(const struct vlltype&loc,
 				 PPackage*pkg, const char*ident);
+extern void pform_package_export(const struct vlltype &loc, PPackage *pkg,
+			         const char *ident);
+PPackage *pform_package_importable(PPackage *pkg, perm_string name);
+PPackage *pform_find_potential_import(const struct vlltype&loc, LexicalScope*scope,
+				      perm_string name, bool tf_call, bool make_explicit);
+
 
 extern PExpr* pform_package_ident(const struct vlltype&loc,
 				  PPackage*pkg, pform_name_t*ident);

pform_package.cc

@@ -72,6 +72,64 @@ void pform_end_package_declaration(const struct vlltype&loc)
       pform_pop_scope();
 }
 
+PPackage *pform_find_potential_import(const struct vlltype&loc, LexicalScope*scope,
+				      perm_string name, bool tf_call, bool make_explicit)
+{
+      assert(scope);
+
+      PPackage *found_pkg = nullptr;
+      for (auto search_pkg : scope->potential_imports) {
+	    PPackage *decl_pkg = pform_package_importable(search_pkg, name);
+	    if (!decl_pkg)
+		  continue;
+
+	    if (found_pkg && found_pkg != decl_pkg && make_explicit) {
+		  cerr << loc.get_fileline() << ": error: "
+			  "Ambiguous use of '" << name << "'. "
+			  "It is exported by both '"
+			<< found_pkg->pscope_name()
+			<< "' and by '"
+			<< search_pkg->pscope_name()
+			<< "'." << endl;
+		  error_count++;
+		  continue;
+	    }
+
+	    found_pkg = decl_pkg;
+	    if (make_explicit) {
+		  if (tf_call)
+			scope->possible_imports[name] = found_pkg;
+		  else {
+			scope->explicit_imports[name] = found_pkg;
+			scope->explicit_imports_from[name].insert(search_pkg);
+		  }
+	    }
+      }
+
+      return found_pkg;
+}
+
+PPackage *pform_package_importable(PPackage *pkg, perm_string name)
+{
+	if (pkg->local_symbols.find(name) != pkg->local_symbols.end())
+		  return pkg;
+
+	auto import_pkg = pkg->explicit_imports.find(name);
+	if (import_pkg == pkg->explicit_imports.end())
+		return nullptr;
+
+	for (auto &exp : pkg->exports) {
+		  // *::* will match all imports, P::* will match all imports
+		  // from a package and P::ID will match a specific identifier
+		  // from a package.
+		if ((!exp.pkg || exp.pkg == import_pkg->second) &&
+		    (exp.name.nil() || exp.name == name))
+			return import_pkg->second;
+	}
+
+	return nullptr;
+}
+
 /*
  * Do the import early, during processing. This requires that the
  * package is declared in pform ahead of time (it is) and that we can
@@ -85,9 +143,8 @@ void pform_package_import(const struct vlltype&loc, PPackage*pkg, const char*ide
 	    perm_string use_ident = lex_strings.make(ident);
 
 	      // Check that the requested symbol is available.
-	    map<perm_string,PNamedItem*>::const_iterator cur_sym
-		  = pkg->local_symbols.find(use_ident);
-	    if (cur_sym == pkg->local_symbols.end()) {
+	    PPackage *pkg_decl = pform_package_importable(pkg, use_ident);
+	    if (!pkg_decl) {
 		  cerr << loc.get_fileline() << ": error: "
 			  "'" << use_ident << "' is not exported by '"
 		       << pkg->pscope_name() << "'." << endl;
@@ -96,7 +153,7 @@ void pform_package_import(const struct vlltype&loc, PPackage*pkg, const char*ide
 	    }
 
 	      // Check for conflict with local symbol.
-	    cur_sym = scope->local_symbols.find(use_ident);
+	    auto cur_sym = scope->local_symbols.find(use_ident);
 	    if (cur_sym != scope->local_symbols.end()) {
 		  cerr << loc.get_fileline() << ": error: "
 			  "'" << use_ident << "' has already been declared "
@@ -112,17 +169,17 @@ void pform_package_import(const struct vlltype&loc, PPackage*pkg, const char*ide
 	    map<perm_string,PPackage*>::const_iterator cur_pkg
 		  = scope->explicit_imports.find(use_ident);
 	    if (cur_pkg != scope->explicit_imports.end()) {
-		  if (cur_pkg->second != pkg) {
+		  if (cur_pkg->second != pkg_decl) {
 			cerr << loc.get_fileline() << ": error: "
 				"'" << use_ident << "' has already been "
 				"imported into this scope from package '"
 			     << cur_pkg->second->pscope_name() << "'." << endl;
 			error_count += 1;
 		  }
-		  return;
 	    }
 
-	    scope->explicit_imports[use_ident] = pkg;
+	    scope->explicit_imports[use_ident] = pkg_decl;
+	    scope->explicit_imports_from[use_ident].insert(pkg);
 
       } else {
 	    list<PPackage*>::const_iterator cur_pkg
@@ -134,6 +191,43 @@ void pform_package_import(const struct vlltype&loc, PPackage*pkg, const char*ide
       }
 }
 
+static bool pform_package_exportable(const struct vlltype &loc, PPackage *pkg,
+				     const perm_string &ident)
+{
+      auto import_pkg = pform_cur_package->explicit_imports_from.find(ident);
+      if (import_pkg != pform_cur_package->explicit_imports_from.end()) {
+	    auto &pkg_list = import_pkg->second;
+	    if (pkg_list.find(pkg) != pkg_list.end())
+		  return true;
+      }
+
+      if (pform_cur_package->local_symbols.find(ident) == pform_cur_package->local_symbols.end()) {
+	    if (pform_find_potential_import(loc, pform_cur_package,
+					    ident, false, true))
+		  return true;
+      }
+
+      cerr << loc.get_fileline() << ": error: "
+	      "`" << ident << "` has not been imported from "
+	   << pkg->pscope_name() << "." << endl;
+      error_count++;
+
+      return false;
+}
+
+void pform_package_export(const struct vlltype &loc, PPackage *pkg, const char *ident)
+{
+      assert(pform_cur_package);
+
+      perm_string use_ident;
+      if (ident) {
+	    use_ident = lex_strings.make(ident);
+	    if (!pform_package_exportable(loc, pkg, use_ident))
+		  return;
+      }
+      pform_cur_package->exports.push_back(PPackage::export_t{pkg, use_ident});
+}
+
 PExpr* pform_package_ident(const struct vlltype&loc,
 			   PPackage*pkg, pform_name_t*ident_name)
 {