Changeset 0a6d2045 for src/ControlStruct/ExceptTranslate.cpp

Timestamp:

Dec 20, 2023, 12:04:33 PM (10 months ago)

Author:

Andrew Beach <ajbeach@…>

Branches:

master

Children:

523e300

Parents:

9fba8e6

Message:

You can how use local control flow out of 'catch' clauses. Added a test to show that it works.

File:

• src/ControlStruct/ExceptTranslate.cpp (modified) (8 diffs)

src/ControlStruct/ExceptTranslate.cpp

@@ -151 +151 @@
                 const ast::DeclWithType * except_obj, ast::CatchClause * modded_handler );
         ast::FunctionDecl * create_terminate_match( CatchList &handlers );
-        ast::CompoundStmt * create_terminate_caller( CodeLocation loc, ast::FunctionDecl * try_wrapper,
-                ast::FunctionDecl * terminate_catch, ast::FunctionDecl * terminate_match );
+        ast::CompoundStmt * create_terminate_caller( const CodeLocation & location,
+                ast::FunctionDecl * try_wrapper, ast::FunctionDecl * terminate_match,
+                CatchList & terminate_handlers );
         ast::FunctionDecl * create_resume_handler( CatchList &handlers );
         ast::CompoundStmt * create_resume_wrapper(
@@ -264 +265 @@
         //     `handler.body`;
         // }
-        // return;
+        // break;
         const CodeLocation & location = clause->location;
 
@@ -295 +296 @@
                                 body,
                         } ),
-                        new ast::ReturnStmt( location, nullptr ),
+                        new ast::BranchStmt( location, ast::BranchStmt::Break,
+                                ast::Label( location ) ),
                 }
         );
@@ -391 +393 @@
         // Index 1..{number of handlers}
         int index = 0;
-        CatchList::iterator it;
-        for ( it = handlers.begin() ; it != handlers.end() ; ++it ) {
+        for ( ast::CatchClause * handler : handlers ) {
                 ++index;
-                ast::CatchClause * handler = *it;
-
-                // Body should have been taken by create_terminate_catch.
-                // xxx - just ignore it?
-                // assert( nullptr == handler->get_body() );
-
-                // Create new body.
-                handler->body = new ast::ReturnStmt( handler->location,
+
+                ast::ptr<ast::Stmt> other_body = new ast::ReturnStmt( handler->location,
                         ast::ConstantExpr::from_int( handler->location, index ) );
-
-                // Create the handler.
+                handler->body.swap( other_body );
+
                 body->push_back( create_single_matcher( except_obj, handler ) );
-                *it = nullptr;
+
+                handler->body.swap( other_body );
         }
 
@@ -425 +421 @@
 
 ast::CompoundStmt * TryMutatorCore::create_terminate_caller(
-                CodeLocation loc,
+                const CodeLocation & loc,
                 ast::FunctionDecl * try_wrapper,
-                ast::FunctionDecl * terminate_catch,
-                ast::FunctionDecl * terminate_match ) {
+                ast::FunctionDecl * terminate_match,
+                CatchList & terminate_handlers ) {
         // {
         //     int __handler_index = __cfaehm_try_terminate(`try`, `match`);
@@ -447 +443 @@
         );
 
+        ast::ObjectDecl * except = make_exception_object( loc );
+        except->init = new ast::SingleInit( loc,
+                new ast::UntypedExpr( loc,
+                        new ast::NameExpr( loc, "__cfaehm_get_current_termination" )
+                )
+        );
+
+        std::vector<ast::ptr<ast::CaseClause>> cases;
+        for ( auto const & [index, handler] : enumerate( terminate_handlers ) ) {
+                cases.emplace_back(
+                        create_terminate_catch_case( except, index + 1, handler ) );
+        }
+        auto switch_stmt = new ast::SwitchStmt( loc,
+                new ast::VariableExpr( loc, index ), std::move( cases ) );
+
         return new ast::CompoundStmt( loc, {
                 new ast::DeclStmt( loc, index ),
                 new ast::IfStmt( loc,
                         new ast::VariableExpr( loc, index ),
-                        new ast::ExprStmt( loc,
-                                new ast::UntypedExpr( loc,
-                                        new ast::VariableExpr( loc, terminate_catch ),
-                                        {
-                                                new ast::VariableExpr( loc, index ),
-                                                new ast::UntypedExpr( loc,
-                                                        new ast::NameExpr( loc, "__cfaehm_get_current_termination" )
-                                                ),
-                                        }
-                                )
-                        )
+                        new ast::CompoundStmt( loc, {
+                                new ast::DeclStmt( loc, except ),
+                                switch_stmt,
+                        } )
                 ),
         } );
@@ -663 +667 @@
 
         if ( termination_handlers.size() ) {
-                // Define the three helper functions.
+                // Define the two helper functions.
                 ast::FunctionDecl * try_wrapper = create_try_wrapper( inner );
                 appendDeclStmt( block, try_wrapper );
-                ast::FunctionDecl * terminate_catch =
-                        create_terminate_catch( termination_handlers );
-                appendDeclStmt( block, terminate_catch );
                 ast::FunctionDecl * terminate_match =
                         create_terminate_match( termination_handlers );
@@ -674 +675 @@
                 // Build the call to the try wrapper.
                 inner = create_terminate_caller(inner->location,
-                        try_wrapper, terminate_catch, terminate_match );
+                        try_wrapper, terminate_match, termination_handlers );
         }