For PR libgcj/7482:

* verify.cc (ref_intersection): New class.
	(type_val): Removed unresolved_reference_type,
	uninitialized_unresolved_reference_type.
	(is_assignable_from_slow): Rewrote.
	(type::data): Removed.
	(type::klass): New field.
	(type::type): Added verifier argument.
	(type::resolve): Removed.
	(type::set_uninitialized): Updated for change to type_val.
	(type::set_initialized): Likewise.
	(type::isinitialized): Likewise.
	(type::print): Likewise.
	(construct_primitive_array_type): Likewise.
	(type::compatible): Updated for change to type_val and to use
	ref_intersection.
	(type::isarray): Updated to use ref_intersection.
	(type::isinterface): Likewise.
	(type::element_type): Likewise.
	(type::to_array): Likewise.
	(type::verify_dimensions): Rewrote.
	(type::merge): Likewise.
	(check_class_constant): Updated for type constructor change.
	(check_constant): Likewise.
	(check_field_constant): Likewise.
	(get_one_type): Likewise.
	(initialize_stack): Likewise.
	(verify_instructions_0): Likewise.
	(verify_instructions_0) [op_invokeinterface]: Removed special
	case.
	(isect_list): New field.
	(_Jv_BytecodeVerifier): Initialize it.
	(~_Jv_BytecodeVerifier): Destroy ref_intersection objects.

From-SVN: r69751
This commit is contained in:
Tom Tromey 2003-07-24 17:18:00 +00:00 committed by Tom Tromey
parent 1c41b3d6cf
commit b6d2b0f7f5
2 changed files with 346 additions and 232 deletions

View File

@ -1,3 +1,39 @@
2003-07-24 Tom Tromey <tromey@redhat.com>
For PR libgcj/7482:
* verify.cc (ref_intersection): New class.
(type_val): Removed unresolved_reference_type,
uninitialized_unresolved_reference_type.
(is_assignable_from_slow): Rewrote.
(type::data): Removed.
(type::klass): New field.
(type::type): Added verifier argument.
(type::resolve): Removed.
(type::set_uninitialized): Updated for change to type_val.
(type::set_initialized): Likewise.
(type::isinitialized): Likewise.
(type::print): Likewise.
(construct_primitive_array_type): Likewise.
(type::compatible): Updated for change to type_val and to use
ref_intersection.
(type::isarray): Updated to use ref_intersection.
(type::isinterface): Likewise.
(type::element_type): Likewise.
(type::to_array): Likewise.
(type::verify_dimensions): Rewrote.
(type::merge): Likewise.
(check_class_constant): Updated for type constructor change.
(check_constant): Likewise.
(check_field_constant): Likewise.
(get_one_type): Likewise.
(initialize_stack): Likewise.
(verify_instructions_0): Likewise.
(verify_instructions_0) [op_invokeinterface]: Removed special
case.
(isect_list): New field.
(_Jv_BytecodeVerifier): Initialize it.
(~_Jv_BytecodeVerifier): Destroy ref_intersection objects.
2003-07-24 H. Väisänen <hvaisane@joyx.joensuu.fi>
* java/text/SimpleDateFormat.java (format) [YEAR_FIELD]: Zero pad

View File

@ -1,4 +1,4 @@
// defineclass.cc - defining a class from .class format.
// verify.cc - verify bytecode
/* Copyright (C) 2001, 2002, 2003 Free Software Foundation
@ -58,6 +58,7 @@ private:
struct subr_info;
struct subr_entry_info;
struct linked_utf8;
struct ref_intersection;
// The current PC.
int PC;
@ -104,6 +105,9 @@ private:
// but without this our utf8 objects would be collected.
linked_utf8 *utf8_list;
// A linked list of all ref_intersection objects we allocate.
ref_intersection *isect_list;
struct linked_utf8
{
_Jv_Utf8Const *val;
@ -189,9 +193,219 @@ private:
// Everything after `reference_type' must be a reference type.
reference_type,
null_type,
unresolved_reference_type,
uninitialized_reference_type,
uninitialized_unresolved_reference_type
uninitialized_reference_type
};
// This represents a merged class type. Some verifiers (including
// earlier versions of this one) will compute the intersection of
// two class types when merging states. However, this loses
// critical information about interfaces implemented by the various
// classes. So instead we keep track of all the actual classes that
// have been merged.
struct ref_intersection
{
// Whether or not this type has been resolved.
bool is_resolved;
// Actual type data.
union
{
// For a resolved reference type, this is a pointer to the class.
jclass klass;
// For other reference types, this it the name of the class.
_Jv_Utf8Const *name;
} data;
// Link to the next reference in the intersection.
ref_intersection *ref_next;
// This is used to keep track of all the allocated
// ref_intersection objects, so we can free them.
// FIXME: we should allocate these in chunks.
ref_intersection *alloc_next;
ref_intersection (jclass klass, _Jv_BytecodeVerifier *verifier)
: ref_next (NULL)
{
is_resolved = true;
data.klass = klass;
alloc_next = verifier->isect_list;
verifier->isect_list = this;
}
ref_intersection (_Jv_Utf8Const *name, _Jv_BytecodeVerifier *verifier)
: ref_next (NULL)
{
is_resolved = false;
data.name = name;
alloc_next = verifier->isect_list;
verifier->isect_list = this;
}
ref_intersection (ref_intersection *dup, ref_intersection *tail,
_Jv_BytecodeVerifier *verifier)
: ref_next (tail)
{
is_resolved = dup->is_resolved;
data = dup->data;
alloc_next = verifier->isect_list;
verifier->isect_list = this;
}
bool equals (ref_intersection *other, _Jv_BytecodeVerifier *verifier)
{
if (! is_resolved && ! other->is_resolved
&& _Jv_equalUtf8Consts (data.name, other->data.name))
return true;
if (! is_resolved)
resolve (verifier);
if (! other->is_resolved)
other->resolve (verifier);
return data.klass == other->data.klass;
}
// Merge THIS type into OTHER, returning the result. This will
// return OTHER if all the classes in THIS already appear in
// OTHER.
ref_intersection *merge (ref_intersection *other,
_Jv_BytecodeVerifier *verifier)
{
ref_intersection *tail = other;
for (ref_intersection *self = this; self != NULL; self = self->ref_next)
{
bool add = true;
for (ref_intersection *iter = other; iter != NULL;
iter = iter->ref_next)
{
if (iter->equals (self, verifier))
{
add = false;
break;
}
}
if (add)
tail = new ref_intersection (self, tail, verifier);
}
return tail;
}
void resolve (_Jv_BytecodeVerifier *verifier)
{
if (is_resolved)
return;
using namespace java::lang;
java::lang::ClassLoader *loader
= verifier->current_class->getClassLoaderInternal();
// We might see either kind of name. Sigh.
if (data.name->data[0] == 'L'
&& data.name->data[data.name->length - 1] == ';')
data.klass = _Jv_FindClassFromSignature (data.name->data, loader);
else
data.klass = Class::forName (_Jv_NewStringUtf8Const (data.name),
false, loader);
is_resolved = true;
}
// See if an object of type OTHER can be assigned to an object of
// type *THIS. This might resolve classes in one chain or the
// other.
bool compatible (ref_intersection *other,
_Jv_BytecodeVerifier *verifier)
{
ref_intersection *self = this;
for (; self != NULL; self = self->ref_next)
{
ref_intersection *other_iter = other;
for (; other_iter != NULL; other_iter = other_iter->ref_next)
{
// Avoid resolving if possible.
if (! self->is_resolved
&& ! other_iter->is_resolved
&& _Jv_equalUtf8Consts (self->data.name,
other_iter->data.name))
continue;
if (! self->is_resolved)
self->resolve(verifier);
if (! other_iter->is_resolved)
other_iter->resolve(verifier);
if (! is_assignable_from_slow (self->data.klass,
other_iter->data.klass))
return false;
}
}
return true;
}
bool isarray ()
{
// assert (ref_next == NULL);
if (is_resolved)
return data.klass->isArray ();
else
return data.name->data[0] == '[';
}
bool isinterface (_Jv_BytecodeVerifier *verifier)
{
// assert (ref_next == NULL);
if (! is_resolved)
resolve (verifier);
return data.klass->isInterface ();
}
bool isabstract (_Jv_BytecodeVerifier *verifier)
{
// assert (ref_next == NULL);
if (! is_resolved)
resolve (verifier);
using namespace java::lang::reflect;
return Modifier::isAbstract (data.klass->getModifiers ());
}
jclass getclass (_Jv_BytecodeVerifier *verifier)
{
if (! is_resolved)
resolve (verifier);
return data.klass;
}
int count_dimensions ()
{
int ndims = 0;
if (is_resolved)
{
jclass k = data.klass;
while (k->isArray ())
{
k = k->getComponentType ();
++ndims;
}
}
else
{
char *p = data.name->data;
while (*p++ == '[')
++ndims;
}
return ndims;
}
void *operator new (size_t bytes)
{
return _Jv_Malloc (bytes);
}
void operator delete (void *mem)
{
_Jv_Free (mem);
}
};
// Return the type_val corresponding to a primitive signature
@ -244,8 +458,21 @@ private:
// TARGET haven't been prepared.
static bool is_assignable_from_slow (jclass target, jclass source)
{
// This will terminate when SOURCE==Object.
while (true)
// First, strip arrays.
while (target->isArray ())
{
// If target is array, source must be as well.
if (! source->isArray ())
return false;
target = target->getComponentType ();
source = source->getComponentType ();
}
// Quick success.
if (target == &java::lang::Object::class$)
return true;
do
{
if (source == target)
return true;
@ -253,14 +480,7 @@ private:
if (target->isPrimitive () || source->isPrimitive ())
return false;
if (target->isArray ())
{
if (! source->isArray ())
return false;
target = target->getComponentType ();
source = source->getComponentType ();
}
else if (target->isInterface ())
if (target->isInterface ())
{
for (int i = 0; i < source->interface_count; ++i)
{
@ -269,33 +489,12 @@ private:
if (is_assignable_from_slow (target, source->interfaces[i]))
return true;
}
source = source->getSuperclass ();
if (source == NULL)
return false;
}
// We must do this check before we check to see if SOURCE is
// an interface. This way we know that any interface is
// assignable to an Object.
else if (target == &java::lang::Object::class$)
return true;
else if (source->isInterface ())
{
for (int i = 0; i < target->interface_count; ++i)
{
// We use a recursive call because we also need to
// check superinterfaces.
if (is_assignable_from_slow (target->interfaces[i], source))
return true;
}
target = target->getSuperclass ();
if (target == NULL)
return false;
}
else if (source == &java::lang::Object::class$)
return false;
else
source = source->getSuperclass ();
}
while (source != NULL);
return false;
}
// This is used to keep track of which `jsr's correspond to a given
@ -324,16 +523,12 @@ private:
// verifier.
struct type
{
// The type.
// The type key.
type_val key;
// Some associated data.
union
{
// For a resolved reference type, this is a pointer to the class.
jclass klass;
// For other reference types, this it the name of the class.
_Jv_Utf8Const *name;
} data;
// For reference types, the representation of the type.
ref_intersection *klass;
// This is used when constructing a new object. It is the PC of the
// `new' instruction which created the object. We use the special
// value -2 to mean that this is uninitialized, and the special
@ -348,7 +543,7 @@ private:
type ()
{
key = unsuitable_type;
data.klass = NULL;
klass = NULL;
pc = UNINIT;
}
@ -357,25 +552,26 @@ private:
type (type_val k)
{
key = k;
data.klass = NULL;
if (key == reference_type)
data.klass = &java::lang::Object::class$;
// For reference_type, if KLASS==NULL then that means we are
// looking for a generic object of any kind, including an
// uninitialized reference.
klass = NULL;
pc = UNINIT;
}
// Make a new instance given a class.
type (jclass klass)
type (jclass k, _Jv_BytecodeVerifier *verifier)
{
key = reference_type;
data.klass = klass;
klass = new ref_intersection (k, verifier);
pc = UNINIT;
}
// Make a new instance given the name of a class.
type (_Jv_Utf8Const *n)
type (_Jv_Utf8Const *n, _Jv_BytecodeVerifier *verifier)
{
key = unresolved_reference_type;
data.name = n;
key = reference_type;
klass = new ref_intersection (n, verifier);
pc = UNINIT;
}
@ -383,7 +579,7 @@ private:
type (const type &t)
{
key = t.key;
data = t.data;
klass = t.klass;
pc = t.pc;
}
@ -402,7 +598,7 @@ private:
type& operator= (type_val k)
{
key = k;
data.klass = NULL;
klass = NULL;
pc = UNINIT;
return *this;
}
@ -410,7 +606,7 @@ private:
type& operator= (const type& t)
{
key = t.key;
data = t.data;
klass = t.klass;
pc = t.pc;
return *this;
}
@ -424,35 +620,11 @@ private:
return *this;
}
// If *THIS is an unresolved reference type, resolve it.
void resolve (_Jv_BytecodeVerifier *verifier)
{
if (key != unresolved_reference_type
&& key != uninitialized_unresolved_reference_type)
return;
using namespace java::lang;
java::lang::ClassLoader *loader
= verifier->current_class->getClassLoaderInternal();
// We might see either kind of name. Sigh.
if (data.name->data[0] == 'L'
&& data.name->data[data.name->length - 1] == ';')
data.klass = _Jv_FindClassFromSignature (data.name->data, loader);
else
data.klass = Class::forName (_Jv_NewStringUtf8Const (data.name),
false, loader);
key = (key == unresolved_reference_type
? reference_type
: uninitialized_reference_type);
}
// Mark this type as the uninitialized result of `new'.
void set_uninitialized (int npc, _Jv_BytecodeVerifier *verifier)
{
if (key == reference_type)
key = uninitialized_reference_type;
else if (key == unresolved_reference_type)
key = uninitialized_unresolved_reference_type;
else
verifier->verify_fail ("internal error in type::uninitialized");
pc = npc;
@ -461,13 +633,9 @@ private:
// Mark this type as now initialized.
void set_initialized (int npc)
{
if (npc != UNINIT && pc == npc
&& (key == uninitialized_reference_type
|| key == uninitialized_unresolved_reference_type))
if (npc != UNINIT && pc == npc && key == uninitialized_reference_type)
{
key = (key == uninitialized_reference_type
? reference_type
: unresolved_reference_type);
key = reference_type;
pc = UNINIT;
}
}
@ -488,14 +656,16 @@ private:
// The `null' type is convertible to any initialized reference
// type.
if (key == null_type || k.key == null_type)
return true;
if (key == null_type)
return k.key != uninitialized_reference_type;
if (k.key == null_type)
return key != uninitialized_reference_type;
// Any reference type is convertible to Object. This is a special
// case so we don't need to unnecessarily resolve a class.
if (key == reference_type
&& data.klass == &java::lang::Object::class$)
// A special case for a generic reference.
if (klass == NULL)
return true;
if (k.klass == NULL)
verifier->verify_fail ("programmer error in type::compatible");
// An initialized type and an uninitialized type are not
// compatible.
@ -511,16 +681,7 @@ private:
return false;
}
// Two unresolved types are equal if their names are the same.
if (! isresolved ()
&& ! k.isresolved ()
&& _Jv_equalUtf8Consts (data.name, k.data.name))
return true;
// We must resolve both types and check assignability.
resolve (verifier);
k.resolve (verifier);
return is_assignable_from_slow (data.klass, k.data.klass);
return klass->compatible(k.klass, verifier);
}
bool isvoid () const
@ -545,9 +706,7 @@ private:
// We treat null_type as not an array. This is ok based on the
// current uses of this method.
if (key == reference_type)
return data.klass->isArray ();
else if (key == unresolved_reference_type)
return data.name->data[0] == '[';
return klass->isarray ();
return false;
}
@ -558,33 +717,28 @@ private:
bool isinterface (_Jv_BytecodeVerifier *verifier)
{
resolve (verifier);
if (key != reference_type)
return false;
return data.klass->isInterface ();
return klass->isinterface (verifier);
}
bool isabstract (_Jv_BytecodeVerifier *verifier)
{
resolve (verifier);
if (key != reference_type)
return false;
using namespace java::lang::reflect;
return Modifier::isAbstract (data.klass->getModifiers ());
return klass->isabstract (verifier);
}
// Return the element type of an array.
type element_type (_Jv_BytecodeVerifier *verifier)
{
// FIXME: maybe should do string manipulation here.
resolve (verifier);
if (key != reference_type)
verifier->verify_fail ("programmer error in type::element_type()", -1);
jclass k = data.klass->getComponentType ();
jclass k = klass->getclass (verifier)->getComponentType ();
if (k->isPrimitive ())
return type (verifier->get_type_val_for_signature (k));
return type (k);
return type (k, verifier);
}
// Return the array type corresponding to an initialized
@ -592,16 +746,12 @@ private:
// types, but currently we don't need to.
type to_array (_Jv_BytecodeVerifier *verifier)
{
// Resolving isn't ideal, because it might force us to load
// another class, but it's easy. FIXME?
if (key == unresolved_reference_type)
resolve (verifier);
if (key == reference_type)
return type (_Jv_GetArrayClass (data.klass,
data.klass->getClassLoaderInternal()));
else
if (key != reference_type)
verifier->verify_fail ("internal error in type::to_array()");
jclass k = klass->getclass (verifier);
return type (_Jv_GetArrayClass (k, k->getClassLoaderInternal()),
verifier);
}
bool isreference () const
@ -616,9 +766,7 @@ private:
bool isinitialized () const
{
return (key == reference_type
|| key == null_type
|| key == unresolved_reference_type);
return key == reference_type || key == null_type;
}
bool isresolved () const
@ -631,24 +779,10 @@ private:
void verify_dimensions (int ndims, _Jv_BytecodeVerifier *verifier)
{
// The way this is written, we don't need to check isarray().
if (key == reference_type)
{
jclass k = data.klass;
while (k->isArray () && ndims > 0)
{
k = k->getComponentType ();
--ndims;
}
}
else
{
// We know KEY == unresolved_reference_type.
char *p = data.name->data;
while (*p++ == '[' && ndims-- > 0)
;
}
if (key != reference_type)
verifier->verify_fail ("internal error in verify_dimensions: not a reference type");
if (ndims > 0)
if (klass->count_dimensions () < ndims)
verifier->verify_fail ("array type has fewer dimensions than required");
}
@ -682,54 +816,13 @@ private:
verifier->verify_fail ("merging different uninitialized types");
}
if (! isresolved ()
&& ! old_type.isresolved ()
&& _Jv_equalUtf8Consts (data.name, old_type.data.name))
ref_intersection *merged = old_type.klass->merge (klass,
verifier);
if (merged != klass)
{
// Types are identical.
}
else
{
resolve (verifier);
old_type.resolve (verifier);
jclass k = data.klass;
jclass oldk = old_type.data.klass;
int arraycount = 0;
while (k->isArray () && oldk->isArray ())
{
++arraycount;
k = k->getComponentType ();
oldk = oldk->getComponentType ();
}
// Ordinarily this terminates when we hit Object...
while (k != NULL)
{
if (is_assignable_from_slow (k, oldk))
break;
k = k->getSuperclass ();
klass = merged;
changed = true;
}
// ... but K could have been an interface, in which
// case we'll end up here. We just convert this
// into Object.
if (k == NULL)
k = &java::lang::Object::class$;
if (changed)
{
while (arraycount > 0)
{
java::lang::ClassLoader *loader
= verifier->current_class->getClassLoaderInternal();
k = _Jv_GetArrayClass (k, loader);
--arraycount;
}
data.klass = k;
}
}
}
}
else if (refo || refn || key != old_type.key)
@ -782,9 +875,7 @@ private:
case unused_by_subroutine_type: c = '_'; break;
case reference_type: c = 'L'; break;
case null_type: c = '@'; break;
case unresolved_reference_type: c = 'l'; break;
case uninitialized_reference_type: c = 'U'; break;
case uninitialized_unresolved_reference_type: c = 'u'; break;
}
debug_print ("%c", c);
}
@ -1624,9 +1715,7 @@ private:
case unused_by_subroutine_type:
case reference_type:
case null_type:
case unresolved_reference_type:
case uninitialized_reference_type:
case uninitialized_unresolved_reference_type:
default:
verify_fail ("unknown type in construct_primitive_array_type");
}
@ -1997,9 +2086,9 @@ private:
check_pool_index (index);
_Jv_Constants *pool = &current_class->constants;
if (pool->tags[index] == JV_CONSTANT_ResolvedClass)
return type (pool->data[index].clazz);
return type (pool->data[index].clazz, this);
else if (pool->tags[index] == JV_CONSTANT_Class)
return type (pool->data[index].utf8);
return type (pool->data[index].utf8, this);
verify_fail ("expected class constant", start_PC);
}
@ -2009,7 +2098,7 @@ private:
_Jv_Constants *pool = &current_class->constants;
if (pool->tags[index] == JV_CONSTANT_ResolvedString
|| pool->tags[index] == JV_CONSTANT_String)
return type (&java::lang::String::class$);
return type (&java::lang::String::class$, this);
else if (pool->tags[index] == JV_CONSTANT_Integer)
return type (int_type);
else if (pool->tags[index] == JV_CONSTANT_Float)
@ -2065,7 +2154,7 @@ private:
if (class_type)
*class_type = ct;
if (field_type->data[0] == '[' || field_type->data[0] == 'L')
return type (field_type);
return type (field_type, this);
return get_type_val_for_signature (field_type->data[0]);
}
@ -2099,7 +2188,7 @@ private:
++p;
++p;
_Jv_Utf8Const *name = make_utf8_const (start, p - start);
return type (name);
return type (name, this);
}
// Casting to jchar here is ok since we are looking at an ASCII
@ -2116,7 +2205,7 @@ private:
jclass k = construct_primitive_array_type (rt);
while (--arraycount > 0)
k = _Jv_GetArrayClass (k, NULL);
return type (k);
return type (k, this);
}
void compute_argument_types (_Jv_Utf8Const *signature,
@ -2160,7 +2249,7 @@ private:
using namespace java::lang::reflect;
if (! Modifier::isStatic (current_method->self->accflags))
{
type kurr (current_class);
type kurr (current_class, this);
if (is_init)
{
kurr.set_uninitialized (type::SELF, this);
@ -2287,7 +2376,7 @@ private:
{
if (PC >= exception[i].start_pc.i && PC < exception[i].end_pc.i)
{
type handler (&java::lang::Throwable::class$);
type handler (&java::lang::Throwable::class$, this);
if (exception[i].handler_type.i != 0)
handler = check_class_constant (exception[i].handler_type.i);
push_exception_jump (handler, exception[i].handler_pc.i);
@ -2959,33 +3048,13 @@ private:
{
// In this case the PC doesn't matter.
t.set_uninitialized (type::UNINIT, this);
// FIXME: check to make sure that the <init>
// call is to the right class.
// It must either be super or an exact class
// match.
}
type raw = pop_raw ();
bool ok = false;
if (! is_init && ! raw.isinitialized ())
{
// This is a failure.
}
else if (is_init && raw.isnull ())
{
// Another failure.
}
else if (t.compatible (raw, this))
{
ok = true;
}
else if (opcode == op_invokeinterface)
{
// This is a hack. We might have merged two
// items and gotten `Object'. This can happen
// because we don't keep track of where merges
// come from. This is safe as long as the
// interpreter checks interfaces at runtime.
type obj (&java::lang::Object::class$);
ok = raw.compatible (obj, this);
}
if (! ok)
if (! t.compatible (raw, this))
verify_fail ("incompatible type on stack");
if (is_init)
@ -3017,7 +3086,8 @@ private:
if (atype < boolean_type || atype > long_type)
verify_fail ("type not primitive", start_PC);
pop_type (int_type);
push_type (construct_primitive_array_type (type_val (atype)));
type t (construct_primitive_array_type (type_val (atype)), this);
push_type (t);
}
break;
case op_anewarray:
@ -3033,7 +3103,7 @@ private:
}
break;
case op_athrow:
pop_type (type (&java::lang::Throwable::class$));
pop_type (type (&java::lang::Throwable::class$, this));
invalidate_pc ();
break;
case op_checkcast:
@ -3178,6 +3248,7 @@ public:
flags = NULL;
jsr_ptrs = NULL;
utf8_list = NULL;
isect_list = NULL;
entry_points = NULL;
}
@ -3220,6 +3291,13 @@ public:
_Jv_Free (entry_points);
entry_points = next;
}
while (isect_list != NULL)
{
ref_intersection *next = isect_list->alloc_next;
delete isect_list;
isect_list = next;
}
}
};