Index: src/ControlStruct/ExceptDecl.cc
===================================================================
--- src/ControlStruct/ExceptDecl.cc	(revision 0c730d99f3adb5e9d0dd1dea118413d63b716406)
+++ src/ControlStruct/ExceptDecl.cc	(revision 0c730d99f3adb5e9d0dd1dea118413d63b716406)
@@ -0,0 +1,238 @@
+//
+// Cforall Version 1.0.0 Copyright (C) 2016 University of Waterloo
+//
+// The contents of this file are covered under the licence agreement in the
+// file "LICENCE" distributed with Cforall.
+//
+// ExceptDecl.cc --
+//
+// Author           : Henry Xue
+// Created On       : Tue Jul 20 04:10:50 2021
+// Last Modified By : Henry Xue
+// Last Modified On : Tue Jul 20 04:10:50 2021
+// Update Count     : 1
+//
+
+#include "ExceptDecl.h"
+
+#include "Common/PassVisitor.h"  // for PassVisitor
+#include "SynTree/Mutator.h"     // for mutateAll
+#include "Virtual/Tables.h"      // for helpers
+
+namespace ControlStruct {
+
+StructDecl * ehmTypeIdStruct( const std::string & exceptionName, std::list< TypeDecl *> * parameters ) {
+	StructDecl * structDecl = new StructDecl( Virtual::typeIdType( exceptionName ) );
+	structDecl->members.push_back( new ObjectDecl(
+		"parent",
+		noStorageClasses,
+		LinkageSpec::Cforall,
+		nullptr,
+		new PointerType( noQualifiers,
+			new TypeInstType( Type::Const, "__cfavir_type_info", false ) ),
+		nullptr
+	) );
+	structDecl->set_body( true );
+	if ( parameters ) {
+		structDecl->parameters = *parameters;
+	}
+	return structDecl;
+}
+
+ObjectDecl * ehmTypeIdValue( const std::string & exceptionName, std::list< Expression *> * parameters ) {
+	StructInstType * structInstType = new StructInstType( Type::Const, Virtual::typeIdType( exceptionName ) );
+	if ( parameters ) {
+		structInstType->parameters = *parameters;
+	}
+	return new ObjectDecl(
+		Virtual::typeIdName( exceptionName ),
+		noStorageClasses,
+		LinkageSpec::Cforall,
+		nullptr,
+		structInstType,
+		new ListInit( { new SingleInit(
+			new AddressExpr( new NameExpr( "__cfatid_exception_t" ) )
+			) }, {}, true ),
+		{ new Attribute( "cfa_linkonce" ) }
+	);
+}
+
+StructDecl * ehmExceptionStructDecl( const std::string & exceptionName, std::list< TypeDecl *> * parameters ) {
+	StructDecl * structDecl = new StructDecl( exceptionName );
+	if ( parameters ) {
+		structDecl->parameters = *parameters;
+	}
+	return structDecl;
+}
+
+StructDecl * ehmVirtualTableStruct( const std::string & exceptionName, std::list< TypeDecl *> * parameters ) {
+	// _EHM_TYPE_ID_TYPE(exception_name) parameters const * __cfavir_typeid;
+	ObjectDecl * typeId = new ObjectDecl(
+		"__cfavir_typeid",
+		noStorageClasses,
+		LinkageSpec::Cforall,
+		nullptr,
+		new PointerType( noQualifiers,
+			new StructInstType( Type::Const, Virtual::typeIdType( exceptionName ) ) ),
+		nullptr
+	);
+
+	// size_t size;
+	ObjectDecl * size = new ObjectDecl(
+		"size",
+		noStorageClasses,
+		LinkageSpec::Cforall,
+		nullptr,
+		new TypeInstType( noQualifiers, "size_t", false ),
+		nullptr
+	);
+	
+	// void (*copy)(exception_name parameters * this, exception_name parameters * other);
+	FunctionType * copyFnType = new FunctionType( noQualifiers, false );
+	copyFnType->get_parameters().push_back( new ObjectDecl(
+		"this",
+		noStorageClasses,
+		LinkageSpec::Cforall,
+		nullptr,
+		new PointerType( noQualifiers,
+			new TypeInstType( noQualifiers, exceptionName, false ) ),
+		nullptr
+	) );
+	copyFnType->get_parameters().push_back( new ObjectDecl(
+		"other",
+		noStorageClasses,
+		LinkageSpec::Cforall,
+		nullptr,
+		new PointerType( noQualifiers,
+			new TypeInstType( noQualifiers, exceptionName, false ) ),
+		nullptr
+	) );
+	copyFnType->get_returnVals().push_back( new ObjectDecl(
+		"",
+		noStorageClasses,
+		LinkageSpec::Cforall,
+		nullptr,
+		new VoidType( noQualifiers ),
+		nullptr
+	) );
+	ObjectDecl * copy = new ObjectDecl(
+		"copy",
+		noStorageClasses,
+		LinkageSpec::Cforall,
+		nullptr,
+		new PointerType( noQualifiers, copyFnType ),
+		nullptr
+	);
+
+	// void (*^?{})(exception_name parameters & this);
+	FunctionType * dtorFnType = new FunctionType( noQualifiers, false );
+	dtorFnType->get_parameters().push_back( new ObjectDecl(
+		"this",
+		noStorageClasses,
+		LinkageSpec::Cforall,
+		nullptr,
+		new ReferenceType( noQualifiers,
+			new TypeInstType( noQualifiers, exceptionName, false ) ),
+		nullptr
+	) );
+	dtorFnType->get_returnVals().push_back( new ObjectDecl(
+		"",
+		noStorageClasses,
+		LinkageSpec::Cforall,
+		nullptr,
+		new VoidType( noQualifiers ),
+		nullptr
+	) );
+	ObjectDecl * dtor = new ObjectDecl(
+		"^?{}",
+		noStorageClasses,
+		LinkageSpec::Cforall,
+		nullptr,
+		new PointerType( noQualifiers, dtorFnType ),
+		nullptr
+	);
+
+	// const char * (*msg)(exception_name parameters * this);
+	FunctionType * msgFnType = new FunctionType( noQualifiers, false );
+	msgFnType->get_parameters().push_back( new ObjectDecl(
+		"this",
+		noStorageClasses,
+		LinkageSpec::Cforall,
+		nullptr,
+		new PointerType( noQualifiers,
+			new TypeInstType( noQualifiers, exceptionName, false ) ),
+		nullptr
+	) );
+	msgFnType->get_returnVals().push_back( new ObjectDecl(
+		"",
+		noStorageClasses,
+		LinkageSpec::Cforall,
+		nullptr,
+		new PointerType( noQualifiers, new BasicType( Type::Const, BasicType::Char ) ),
+		nullptr
+	) );
+	ObjectDecl * msg = new ObjectDecl(
+		"msg",
+		noStorageClasses,
+		LinkageSpec::Cforall,
+		nullptr,
+		new PointerType( noQualifiers, msgFnType ),
+		nullptr
+	);
+
+	StructDecl * structDecl = new StructDecl( Virtual::vtableTypeName( exceptionName ) );
+	structDecl->members.push_back( typeId );
+	structDecl->members.push_back( size );
+	structDecl->members.push_back( copy );
+	structDecl->members.push_back( dtor );
+	structDecl->members.push_back( msg );
+	structDecl->set_body( true );
+	if ( parameters ) {
+		structDecl->parameters = *parameters;
+	}
+	return structDecl;
+}
+
+StructDecl * ehmExceptionStruct( const std::string & exceptionName, const std::list<Declaration*> & members,
+								 std::list<TypeDecl *> * parameters ) {
+	StructDecl * structDecl = new StructDecl( exceptionName );
+	structDecl->members = members;
+	structDecl->members.push_front( new ObjectDecl(
+		"virtual_table",
+		noStorageClasses,
+		LinkageSpec::Cforall,
+		nullptr,
+		new PointerType( noQualifiers,
+			new StructInstType( Type::Const, Virtual::vtableTypeName( exceptionName ) ) ),
+		nullptr
+	) );
+	structDecl->set_body( true );
+	if ( parameters ) {
+		structDecl->parameters = *parameters;
+	}
+	return structDecl;
+}
+
+class ExceptDeclCore : public WithDeclsToAdd {
+public:
+	Declaration * postmutate( StructDecl * structDecl );
+};
+
+Declaration * ExceptDeclCore::postmutate( StructDecl * structDecl ) {
+	if ( structDecl->is_exception() ) {
+		const std::string & exceptionName = structDecl->name;
+		declsToAddBefore.push_back( ehmTypeIdStruct( exceptionName, nullptr ) );
+		declsToAddBefore.push_back( ehmTypeIdValue( exceptionName, nullptr ) );
+		declsToAddBefore.push_back( ehmExceptionStructDecl( exceptionName, nullptr ) );
+		declsToAddBefore.push_back( ehmVirtualTableStruct( exceptionName, nullptr ) );
+		return ehmExceptionStruct( exceptionName, structDecl->get_members(), nullptr );
+	}
+	return structDecl;
+}
+
+void translateExcept( std::list< Declaration *> & translationUnit ) {
+	PassVisitor<ExceptDeclCore> translator;
+	mutateAll( translationUnit, translator );
+}
+
+}
Index: src/ControlStruct/ExceptDecl.h
===================================================================
--- src/ControlStruct/ExceptDecl.h	(revision 0c730d99f3adb5e9d0dd1dea118413d63b716406)
+++ src/ControlStruct/ExceptDecl.h	(revision 0c730d99f3adb5e9d0dd1dea118413d63b716406)
@@ -0,0 +1,24 @@
+//
+// Cforall Version 1.0.0 Copyright (C) 2016 University of Waterloo
+//
+// The contents of this file are covered under the licence agreement in the
+// file "LICENCE" distributed with Cforall.
+//
+// ExceptDecl.h --
+//
+// Author           : Henry Xue
+// Created On       : Tue Jul 20 04:10:50 2021
+// Last Modified By : Henry Xue
+// Last Modified On : Tue Jul 20 04:10:50 2021
+// Update Count     : 1
+//
+
+#pragma once
+
+#include <list>  // for list
+
+class Declaration;
+
+namespace ControlStruct {
+	void translateExcept( std::list< Declaration *> & translationUnit );
+}
Index: src/ControlStruct/module.mk
===================================================================
--- src/ControlStruct/module.mk	(revision 5339a87ca7689b734a2eb1d355830ea9713784a1)
+++ src/ControlStruct/module.mk	(revision 0c730d99f3adb5e9d0dd1dea118413d63b716406)
@@ -10,10 +10,12 @@
 ## Author           : Richard C. Bilson
 ## Created On       : Mon Jun  1 17:49:17 2015
-## Last Modified By : Andrew Beach
-## Last Modified On : Wed Jun 28 16:15:00 2017
-## Update Count     : 4
+## Last Modified By : Henry Xue
+## Last Modified On : Tue Jul 20 04:10:50 2021
+## Update Count     : 5
 ###############################################################################
 
 SRC_CONTROLSTRUCT = \
+	ControlStruct/ExceptDecl.cc \
+	ControlStruct/ExceptDecl.h \
 	ControlStruct/ForExprMutator.cc \
 	ControlStruct/ForExprMutator.h \