Changeset 69c5c00

Timestamp:

Oct 7, 2020, 6:08:35 PM (4 years ago)

Author:

Andrew Beach <ajbeach@…>

Branches:

ADT, arm-eh, ast-experimental, enum, forall-pointer-decay, jacob/cs343-translation, master, new-ast-unique-expr, pthread-emulation, qualifiedEnum

Children:

6fbe9a5

Parents:

41b8ea4

Message:

Rework exceptions mark_exception -> get_exception_vtable and the needed follow up.

Files:

• libcfa/src/concurrency/coroutine.cfa (modified) (3 diffs)
• libcfa/src/concurrency/coroutine.hfa (modified) (3 diffs)
• libcfa/src/exception.h (modified) (3 diffs)
• libcfa/src/exception.hfa (modified) (5 diffs)
• src/Concurrency/Keywords.cc (modified) (6 diffs)
• src/SynTree/AggregateDecl.cc (modified) (2 diffs)
• src/SynTree/Declaration.h (modified) (1 diff)
• src/Virtual/Tables.cc (modified) (5 diffs)
• src/Virtual/Tables.h (modified) (1 diff)
• tests/exceptions/defaults.cfa (modified) (1 diff)

libcfa/src/concurrency/coroutine.cfa

@@ -47 +47 @@
 
 //-----------------------------------------------------------------------------
-FORALL_DATA_INSTANCE(CoroutineCancelled,
-                (dtype coroutine_t | sized(coroutine_t)), (coroutine_t))
+FORALL_DATA_INSTANCE(CoroutineCancelled, (dtype coroutine_t), (coroutine_t))
 
 struct __cfaehm_node {
@@ -59 +58 @@
 void mark_exception(CoroutineCancelled(T) *) {}
 
-forall(dtype T | sized(T))
+forall(dtype T)
 void copy(CoroutineCancelled(T) * dst, CoroutineCancelled(T) * src) {
         dst->the_coroutine = src->the_coroutine;
@@ -77 +76 @@
         exception_t * except = (exception_t *)(1 + (__cfaehm_node *)desc->cancellation);
 
+        // TODO: Remove explitate vtable set once trac#186 is fixed.
         CoroutineCancelled(T) except;
+        except.virtual_table = &get_exception_vtable(&except);
         except.the_coroutine = &cor;
         except.the_exception = except;

libcfa/src/concurrency/coroutine.hfa

@@ -22 +22 @@
 //-----------------------------------------------------------------------------
 // Exception thrown from resume when a coroutine stack is cancelled.
-// Should not have to be be sized (see trac #196).
-FORALL_DATA_EXCEPTION(CoroutineCancelled,
-                (dtype coroutine_t | sized(coroutine_t)), (coroutine_t)) (
+FORALL_DATA_EXCEPTION(CoroutineCancelled, (dtype coroutine_t), (coroutine_t)) (
         coroutine_t * the_coroutine;
         exception_t * the_exception;
@@ -30 +28 @@
 
 forall(dtype T)
-void mark_exception(CoroutineCancelled(T) *);
-
-forall(dtype T | sized(T))
 void copy(CoroutineCancelled(T) * dst, CoroutineCancelled(T) * src);
 
@@ -42 +37 @@
 // Anything that implements this trait can be resumed.
 // Anything that is resumed is a coroutine.
-trait is_coroutine(dtype T | sized(T)
-                | is_resumption_exception(CoroutineCancelled(T))
-                | VTABLE_ASSERTION(CoroutineCancelled, (T))) {
+trait is_coroutine(dtype T
+                | is_resumption_exception(CoroutineCancelled(T),
+                        CoroutineCancelled_vtable(T))) {
         void main(T & this);
         $coroutine * get_coroutine(T & this);

libcfa/src/exception.h

@@ -76 +76 @@
 // implemented in the .c file either so they all have to be inline.
 
-trait is_exception(dtype exceptT) {
+trait is_exception(dtype exceptT, dtype virtualT) {
         /* The first field must be a pointer to a virtual table.
-         * That virtual table must be a decendent of the base exception virtual tab$
+         * That virtual table must be a decendent of the base exception virtual table.
          */
-        void mark_exception(exceptT *);
-        // This is never used and should be a no-op.
+        virtualT const & get_exception_vtable(exceptT *);
+        // Always returns the virtual table for this type (associated types hack).
 };
 
-trait is_termination_exception(dtype exceptT | is_exception(exceptT)) {
+trait is_termination_exception(dtype exceptT, dtype virtualT | is_exception(exceptT, virtualT)) {
         void defaultTerminationHandler(exceptT &);
 };
 
-trait is_resumption_exception(dtype exceptT | is_exception(exceptT)) {
+trait is_resumption_exception(dtype exceptT, dtype virtualT | is_exception(exceptT, virtualT)) {
         void defaultResumptionHandler(exceptT &);
 };
 
-forall(dtype exceptT | is_termination_exception(exceptT))
+forall(dtype exceptT, dtype virtualT | is_termination_exception(exceptT, virtualT))
 static inline void $throw(exceptT & except) {
         __cfaehm_throw_terminate(
@@ -100 +100 @@
 }
 
-forall(dtype exceptT | is_resumption_exception(exceptT))
+forall(dtype exceptT, dtype virtualT | is_resumption_exception(exceptT, virtualT))
 static inline void $throwResume(exceptT & except) {
         __cfaehm_throw_resume(
@@ -108 +108 @@
 }
 
-forall(dtype exceptT | is_exception(exceptT))
+forall(dtype exceptT, dtype virtualT | is_exception(exceptT, virtualT))
 static inline void cancel_stack(exceptT & except) __attribute__((noreturn)) {
         __cfaehm_cancel_stack( (exception_t *)&except );
 }
 
-forall(dtype exceptT | is_exception(exceptT))
+forall(dtype exceptT, dtype virtualT | is_exception(exceptT, virtualT))
 static inline void defaultTerminationHandler(exceptT & except) {
         return cancel_stack( except );
 }
 
-forall(dtype exceptT | is_exception(exceptT))
+forall(dtype exceptT, dtype virtualT | is_exception(exceptT, virtualT))
 static inline void defaultResumptionHandler(exceptT & except) {
         throw except;

libcfa/src/exception.hfa

@@ -95 +95 @@
 // visible anywhere you use the instantiation of the exception is used.
 #define POLY_VTABLE_DECLARATION(exception_name, ...) \
-        void mark_exception(exception_name(__VA_ARGS__) *); \
+        VTABLE_TYPE(exception_name)(__VA_ARGS__) const & get_exception_vtable(exception_name(__VA_ARGS__) *); \
         extern VTABLE_TYPE(exception_name)(__VA_ARGS__) VTABLE_NAME(exception_name)
 
@@ -160 +160 @@
 
 #define _FORALL_CTOR0_DECLARATION(exception_name, assertions, parameters) \
-        forall(_UNPACK assertions | VTABLE_ASSERTION(exception_name, parameters) ) \
+        forall(_UNPACK assertions | \
+                is_exception(exception_name parameters, VTABLE_TYPE(exception_name) parameters)) \
         void ?{}(exception_name parameters & this)
 
 #define _FORALL_CTOR0_INSTANCE(exception_name, assertions, parameters) \
         _FORALL_CTOR0_DECLARATION(exception_name, assertions, parameters) { \
-                VTABLE_INIT(this, exception_name); \
+                (this).virtual_table = &get_exception_vtable(&this); \
         }
 
@@ -185 +186 @@
 #define _VTABLE_DECLARATION(exception_name, parent_name, ...) \
         struct exception_name; \
-        void mark_exception(exception_name *); \
         VTABLE_TYPE(exception_name); \
+        VTABLE_TYPE(exception_name) const & get_exception_vtable(exception_name *); \
         extern VTABLE_TYPE(exception_name) VTABLE_NAME(exception_name); \
         VTABLE_TYPE(exception_name) { \
@@ -197 +198 @@
 
 #define _VTABLE_INSTANCE(exception_name, parent_name, ...) \
-        void mark_exception(exception_name *) {} \
+        VTABLE_TYPE(exception_name) const & get_exception_vtable(exception_name *) { \
+                return VTABLE_NAME(exception_name); \
+        } \
         void _GLUE2(exception_name,_copy)(exception_name * this, exception_name * other) { \
                 *this = *other; \
@@ -218 +221 @@
 
 #define _POLY_VTABLE_INSTANCE(exception_name, parent_name, ...) \
-        void mark_exception(exception_name(__VA_ARGS__) *) {} \
+        extern VTABLE_TYPE(exception_name)(__VA_ARGS__) VTABLE_NAME(exception_name); \
+        VTABLE_TYPE(exception_name)(__VA_ARGS__) const & get_exception_vtable( \
+                        exception_name(__VA_ARGS__) *) { \
+                return VTABLE_NAME(exception_name); \
+        } \
         void _GLUE2(exception_name,_copy)( \
                         exception_name(__VA_ARGS__) * this, exception_name(__VA_ARGS__) * other) { \

src/Concurrency/Keywords.cc

@@ -66 +66 @@
                         bool needs_main, AggregateDecl::Aggregate cast_target ) :
                   type_name( type_name ), field_name( field_name ), getter_name( getter_name ),
-                  context_error( context_error ), vtable_name( getVTableName( exception_name ) ),
+                  context_error( context_error ), exception_name( exception_name ),
+                  vtable_name( getVTableName( exception_name ) ),
                   needs_main( needs_main ), cast_target( cast_target ) {}
 
@@ -89 +90 @@
                 const std::string getter_name;
                 const std::string context_error;
+                const std::string exception_name;
                 const std::string vtable_name;
                 bool needs_main;
@@ -95 +97 @@
                 StructDecl   * type_decl = nullptr;
                 FunctionDecl * dtor_decl = nullptr;
+                StructDecl * except_decl = nullptr;
                 StructDecl * vtable_decl = nullptr;
         };
@@ -376 +379 @@
                 else if ( is_target(decl) ) {
                         handle( decl );
+                }
+                else if ( !except_decl && exception_name == decl->name && decl->body ) {
+                        except_decl = decl;
                 }
                 else if ( !vtable_decl && vtable_name == decl->name && decl->body ) {
@@ -398 +404 @@
                         assert( struct_type );
 
-                        declsToAddAfter.push_back( Virtual::makeVtableInstance( vtable_decl, {
-                                new TypeExpr( struct_type->clone() ),
-                        }, struct_type, nullptr ) );
+                        std::list< Expression * > poly_args = { new TypeExpr( struct_type->clone() ) };
+                        ObjectDecl * vtable_object = Virtual::makeVtableInstance(
+                                vtable_decl->makeInst( poly_args ), struct_type, nullptr );
+                        declsToAddAfter.push_back( vtable_object );
+                        declsToAddAfter.push_back( Virtual::makeGetExceptionFunction(
+                                vtable_object, except_decl->makeInst( std::move( poly_args ) )
+                        ) );
                 }
 
@@ -434 +444 @@
         void ConcurrentSueKeyword::addVtableForward( StructDecl * decl ) {
                 if ( vtable_decl ) {
-                        declsToAddBefore.push_back( Virtual::makeVtableForward( vtable_decl, {
+                        std::list< Expression * > poly_args = {
                                 new TypeExpr( new StructInstType( noQualifiers, decl ) ),
-                        } ) );
+                        };
+                        declsToAddBefore.push_back( Virtual::makeGetExceptionForward(
+                                vtable_decl->makeInst( poly_args ),
+                                except_decl->makeInst( poly_args )
+                        ) );
+                        declsToAddBefore.push_back( Virtual::makeVtableForward(
+                                vtable_decl->makeInst( move( poly_args ) ) ) );
                 // Its only an error if we want a vtable and don't have one.
                 } else if ( ! vtable_name.empty() ) {

src/SynTree/AggregateDecl.cc

@@ -21 +21 @@
 #include "Common/utility.h"      // for printAll, cloneAll, deleteAll
 #include "Declaration.h"         // for AggregateDecl, TypeDecl, Declaration
+#include "Expression.h"
 #include "Initializer.h"
 #include "LinkageSpec.h"         // for Spec, linkageName, Cforall
@@ -88 +89 @@
 const char * StructDecl::typeString() const { return aggrString( kind ); }
 
+StructInstType * StructDecl::makeInst( std::list< Expression * > const & new_parameters ) {
+        std::list< Expression * > copy_parameters;
+        cloneAll( new_parameters, copy_parameters );
+        return makeInst( move( copy( copy_parameters ) ) );
+}
+
+StructInstType * StructDecl::makeInst( std::list< Expression * > && new_parameters ) {
+        assert( parameters.size() == new_parameters.size() );
+        StructInstType * type = new StructInstType( noQualifiers, this );
+        type->parameters = std::move( new_parameters );
+        return type;
+}
+
 const char * UnionDecl::typeString() const { return aggrString( Union ); }
 

src/SynTree/Declaration.h

@@ -306 +306 @@
         bool is_thread   () { return kind == Thread   ; }
 
+        // Make a type instance of this declaration.
+        StructInstType * makeInst( std::list< Expression * > const & parameters );
+        StructInstType * makeInst( std::list< Expression * > && parameters );
+
         virtual StructDecl * clone() const override { return new StructDecl( *this ); }
         virtual void accept( Visitor & v ) override { v.visit( this ); }

src/Virtual/Tables.cc

@@ -14 +14 @@
 //
 
+#include <SynTree/Attribute.h>
 #include <SynTree/Declaration.h>
 #include <SynTree/Expression.h>
+#include <SynTree/Statement.h>
 #include <SynTree/Type.h>
 
@@ -38 +40 @@
 }
 
-// Fuse base polymorphic declaration and forall arguments into a new type.
-static StructInstType * vtableInstType(
-                StructDecl * polyDecl, std::list< Expression * > && parameters ) {
-        assert( parameters.size() == polyDecl->parameters.size() );
-        StructInstType * type = new StructInstType(
-                        Type::Qualifiers( /* Type::Const */ ), polyDecl );
-        type->parameters = std::move( parameters );
-        return type;
-}
-
 static ObjectDecl * makeVtableDeclaration(
                 StructInstType * type, Initializer * init ) {
@@ -66 +58 @@
 
 ObjectDecl * makeVtableForward( StructInstType * type ) {
+        assert( type );
         return makeVtableDeclaration( type, nullptr );
 }
 
-ObjectDecl * makeVtableForward(
-                StructDecl * polyDecl, std::list< Expression * > && parameters ) {
-        return makeVtableForward( vtableInstType( polyDecl, std::move( parameters ) ) );
-}
-
 ObjectDecl * makeVtableInstance(
-                StructInstType * vtableType, Type * vobject_type, Initializer * init ) {
+                StructInstType * vtableType, Type * objectType, Initializer * init ) {
+        assert( vtableType );
+        assert( objectType );
         StructDecl * vtableStruct = vtableType->baseStruct;
         // Build the initialization
@@ -92 +82 @@
                                                 new SingleInit( new AddressExpr( new NameExpr( parentInstance ) ) ) );
                         } else if ( std::string( "size" ) == field->name ) {
-                                inits.push_back( new SingleInit( new SizeofExpr( vobject_type->clone() ) ) );
+                                inits.push_back( new SingleInit( new SizeofExpr( objectType->clone() ) ) );
                         } else if ( std::string( "align" ) == field->name ) {
-                                inits.push_back( new SingleInit( new AlignofExpr( vobject_type->clone() ) ) );
+                                inits.push_back( new SingleInit( new AlignofExpr( objectType->clone() ) ) );
                         } else {
                                 inits.push_back( new SingleInit( new NameExpr( field->name ) ) );
@@ -108 +98 @@
 }
 
-ObjectDecl * makeVtableInstance(
-                StructDecl * polyDecl, std::list< Expression * > && parameters,
-                Type * vobject, Initializer * init ) {
-        return makeVtableInstance(
-                vtableInstType( polyDecl, std::move( parameters ) ), vobject, init );
+namespace {
+        std::string const functionName = "get_exception_vtable";
+}
+
+FunctionDecl * makeGetExceptionForward(
+                Type * vtableType, Type * exceptType ) {
+        assert( vtableType );
+        assert( exceptType );
+        FunctionType * type = new FunctionType( noQualifiers, false );
+        vtableType->tq.is_const = true;
+        type->returnVals.push_back( new ObjectDecl(
+                "_retvalue",
+                noStorageClasses,
+                LinkageSpec::Cforall,
+                nullptr,
+                new ReferenceType( noQualifiers, vtableType ),
+                nullptr,
+        { new Attribute("unused") }
+        ) );
+        type->parameters.push_back( new ObjectDecl(
+                "__unused",
+                noStorageClasses,
+                LinkageSpec::Cforall,
+                nullptr,
+                new PointerType( noQualifiers, exceptType ),
+                nullptr,
+                { new Attribute("unused") }
+        ) );
+        return new FunctionDecl(
+                functionName,
+                noStorageClasses,
+                LinkageSpec::Cforall,
+                type,
+                nullptr
+        );
+}
+
+FunctionDecl * makeGetExceptionFunction(
+                ObjectDecl * vtableInstance, Type * exceptType ) {
+        assert( vtableInstance );
+        assert( exceptType );
+        FunctionDecl * func = makeGetExceptionForward(
+                vtableInstance->type->clone(), exceptType );
+        func->statements = new CompoundStmt( {
+                new ReturnStmt( new VariableExpr( vtableInstance ) ),
+        } );
+        return func;
 }
 

src/Virtual/Tables.h

@@ -27 +27 @@
 bool isVTableInstanceName( std::string const & name );
 
-/// Converts exceptions into regular structures.
-//void ( std::list< Declaration * > & translationUnit );
-
-ObjectDecl * makeVtableForward( StructInstType * );
-ObjectDecl * makeVtableForward( StructDecl *, std::list< Expression * > && );
-/* Create a forward definition of a vtable of the given type.
- *
- * Instead of the virtual table type you may provide the declaration and all
- * the forall parameters.
+ObjectDecl * makeVtableForward( StructInstType * vtableType );
+/* Create a forward declaration of a vtable of the given type.
+ * vtableType node is consumed.
  */
 
-ObjectDecl * makeVtableInstance( StructInstType *, Type *, Initializer * );
-ObjectDecl * makeVtableInstance(
-        StructDecl *, std::list< Expression * > &&, Type *, Initializer * );
+ObjectDecl * makeVtableInstance( StructInstType * vtableType, Type * objectType,
+        Initializer * init = nullptr );
 /* Create an initialized definition of a vtable.
- *
- * The parameters are the virtual table type (or the base declaration and the
- * forall parameters), the object type and optionally an initializer.
- *
- * Instead of the virtual table type you may provide the declaration and all
- * the forall parameters.
+ * vtableType and init (if provided) nodes are consumed.
+ */
+
+// Some special code for how exceptions interact with virtual tables.
+FunctionDecl * makeGetExceptionForward( Type * vtableType, Type * exceptType );
+/* Create a forward declaration of the exception virtual function
+ * linking the vtableType to the exceptType. Both nodes are consumed.
+ */
+
+FunctionDecl * makeGetExceptionFunction(
+        ObjectDecl * vtableInstance, Type * exceptType );
+/* Create the definition of the exception virtual function.
+ * exceptType node is consumed.
  */
 

tests/exceptions/defaults.cfa

@@ -55 +55 @@
 
 void unhandled_test(void) {
-        forall(dtype T | is_exception(T))
+        forall(dtype T, dtype V | is_exception(T, V))
         void defaultTerminationHandler(T &) {
                 throw (unhandled_exception){};