+++ /dev/null
-// defineclass.cc - defining a class from .class format.
-
-/* Copyright (C) 2001, 2002 Free Software Foundation
-
- This file is part of libgcj.
-
-This software is copyrighted work licensed under the terms of the
-Libgcj License. Please consult the file "LIBGCJ_LICENSE" for
-details. */
-
-// Written by Tom Tromey <tromey@redhat.com>
-
-// Define VERIFY_DEBUG to enable debugging output.
-
-#include <config.h>
-
-#include <jvm.h>
-#include <gcj/cni.h>
-#include <java-insns.h>
-#include <java-interp.h>
-
-#ifdef INTERPRETER
-
-#include <java/lang/Class.h>
-#include <java/lang/VerifyError.h>
-#include <java/lang/Throwable.h>
-#include <java/lang/reflect/Modifier.h>
-#include <java/lang/StringBuffer.h>
-
-#ifdef VERIFY_DEBUG
-#include <stdio.h>
-#endif /* VERIFY_DEBUG */
-
-
-static void debug_print (const char *fmt, ...)
- __attribute__ ((format (printf, 1, 2)));
-
-static inline void
-debug_print (const char *fmt, ...)
-{
-#ifdef VERIFY_DEBUG
- va_list ap;
- va_start (ap, fmt);
- vfprintf (stderr, fmt, ap);
- va_end (ap);
-#endif /* VERIFY_DEBUG */
-}
-
-class _Jv_BytecodeVerifier
-{
-private:
-
- static const int FLAG_INSN_START = 1;
- static const int FLAG_BRANCH_TARGET = 2;
-
- struct state;
- struct type;
- struct subr_info;
- struct subr_entry_info;
- struct linked_utf8;
-
- // The current PC.
- int PC;
- // The PC corresponding to the start of the current instruction.
- int start_PC;
-
- // The current state of the stack, locals, etc.
- state *current_state;
-
- // We store the state at branch targets, for merging. This holds
- // such states.
- state **states;
-
- // We keep a linked list of all the PCs which we must reverify.
- // The link is done using the PC values. This is the head of the
- // list.
- int next_verify_pc;
-
- // We keep some flags for each instruction. The values are the
- // FLAG_* constants defined above.
- char *flags;
-
- // We need to keep track of which instructions can call a given
- // subroutine. FIXME: this is inefficient. We keep a linked list
- // of all calling `jsr's at at each jsr target.
- subr_info **jsr_ptrs;
-
- // We keep a linked list of entries which map each `ret' instruction
- // to its unique subroutine entry point. We expect that there won't
- // be many `ret' instructions, so a linked list is ok.
- subr_entry_info *entry_points;
-
- // The bytecode itself.
- unsigned char *bytecode;
- // The exceptions.
- _Jv_InterpException *exception;
-
- // Defining class.
- jclass current_class;
- // This method.
- _Jv_InterpMethod *current_method;
-
- // A linked list of utf8 objects we allocate. This is really ugly,
- // but without this our utf8 objects would be collected.
- linked_utf8 *utf8_list;
-
- struct linked_utf8
- {
- _Jv_Utf8Const *val;
- linked_utf8 *next;
- };
-
- _Jv_Utf8Const *make_utf8_const (char *s, int len)
- {
- _Jv_Utf8Const *val = _Jv_makeUtf8Const (s, len);
- _Jv_Utf8Const *r = (_Jv_Utf8Const *) _Jv_Malloc (sizeof (_Jv_Utf8Const)
- + val->length
- + 1);
- r->length = val->length;
- r->hash = val->hash;
- memcpy (r->data, val->data, val->length + 1);
-
- linked_utf8 *lu = (linked_utf8 *) _Jv_Malloc (sizeof (linked_utf8));
- lu->val = r;
- lu->next = utf8_list;
- utf8_list = lu;
-
- return r;
- }
-
- // This enum holds a list of tags for all the different types we
- // need to handle. Reference types are treated specially by the
- // type class.
- enum type_val
- {
- void_type,
-
- // The values for primitive types are chosen to correspond to values
- // specified to newarray.
- boolean_type = 4,
- char_type = 5,
- float_type = 6,
- double_type = 7,
- byte_type = 8,
- short_type = 9,
- int_type = 10,
- long_type = 11,
-
- // Used when overwriting second word of a double or long in the
- // local variables. Also used after merging local variable states
- // to indicate an unusable value.
- unsuitable_type,
- return_address_type,
- continuation_type,
-
- // There is an obscure special case which requires us to note when
- // a local variable has not been used by a subroutine. See
- // push_jump_merge for more information.
- unused_by_subroutine_type,
-
- // Everything after `reference_type' must be a reference type.
- reference_type,
- null_type,
- unresolved_reference_type,
- uninitialized_reference_type,
- uninitialized_unresolved_reference_type
- };
-
- // Return the type_val corresponding to a primitive signature
- // character. For instance `I' returns `int.class'.
- type_val get_type_val_for_signature (jchar sig)
- {
- type_val rt;
- switch (sig)
- {
- case 'Z':
- rt = boolean_type;
- break;
- case 'B':
- rt = byte_type;
- break;
- case 'C':
- rt = char_type;
- break;
- case 'S':
- rt = short_type;
- break;
- case 'I':
- rt = int_type;
- break;
- case 'J':
- rt = long_type;
- break;
- case 'F':
- rt = float_type;
- break;
- case 'D':
- rt = double_type;
- break;
- case 'V':
- rt = void_type;
- break;
- default:
- verify_fail ("invalid signature");
- }
- return rt;
- }
-
- // Return the type_val corresponding to a primitive class.
- type_val get_type_val_for_signature (jclass k)
- {
- return get_type_val_for_signature ((jchar) k->method_count);
- }
-
- // This is like _Jv_IsAssignableFrom, but it works even if SOURCE or
- // TARGET haven't been prepared.
- static bool is_assignable_from_slow (jclass target, jclass source)
- {
- // This will terminate when SOURCE==Object.
- while (true)
- {
- if (source == target)
- return true;
-
- 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 ())
- {
- for (int i = 0; i < source->interface_count; ++i)
- {
- // We use a recursive call because we also need to
- // check superinterfaces.
- 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 ();
- }
- }
-
- // This is used to keep track of which `jsr's correspond to a given
- // jsr target.
- struct subr_info
- {
- // PC of the instruction just after the jsr.
- int pc;
- // Link.
- subr_info *next;
- };
-
- // This is used to keep track of which subroutine entry point
- // corresponds to which `ret' instruction.
- struct subr_entry_info
- {
- // PC of the subroutine entry point.
- int pc;
- // PC of the `ret' instruction.
- int ret_pc;
- // Link.
- subr_entry_info *next;
- };
-
- // The `type' class is used to represent a single type in the
- // verifier.
- struct type
- {
- // The type.
- 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;
- // 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
- // value -1 for the case where the current method is itself the
- // <init> method.
- int pc;
-
- static const int UNINIT = -2;
- static const int SELF = -1;
-
- // Basic constructor.
- type ()
- {
- key = unsuitable_type;
- data.klass = NULL;
- pc = UNINIT;
- }
-
- // Make a new instance given the type tag. We assume a generic
- // `reference_type' means Object.
- type (type_val k)
- {
- key = k;
- data.klass = NULL;
- if (key == reference_type)
- data.klass = &java::lang::Object::class$;
- pc = UNINIT;
- }
-
- // Make a new instance given a class.
- type (jclass klass)
- {
- key = reference_type;
- data.klass = klass;
- pc = UNINIT;
- }
-
- // Make a new instance given the name of a class.
- type (_Jv_Utf8Const *n)
- {
- key = unresolved_reference_type;
- data.name = n;
- pc = UNINIT;
- }
-
- // Copy constructor.
- type (const type &t)
- {
- key = t.key;
- data = t.data;
- pc = t.pc;
- }
-
- // These operators are required because libgcj can't link in
- // -lstdc++.
- void *operator new[] (size_t bytes)
- {
- return _Jv_Malloc (bytes);
- }
-
- void operator delete[] (void *mem)
- {
- _Jv_Free (mem);
- }
-
- type& operator= (type_val k)
- {
- key = k;
- data.klass = NULL;
- pc = UNINIT;
- return *this;
- }
-
- type& operator= (const type& t)
- {
- key = t.key;
- data = t.data;
- pc = t.pc;
- return *this;
- }
-
- // Promote a numeric type.
- type &promote ()
- {
- if (key == boolean_type || key == char_type
- || key == byte_type || key == short_type)
- key = int_type;
- 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->getClassLoader();
- // 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;
- }
-
- // 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))
- {
- key = (key == uninitialized_reference_type
- ? reference_type
- : unresolved_reference_type);
- pc = UNINIT;
- }
- }
-
-
- // Return true if an object of type K can be assigned to a variable
- // of type *THIS. Handle various special cases too. Might modify
- // *THIS or K. Note however that this does not perform numeric
- // promotion.
- bool compatible (type &k, _Jv_BytecodeVerifier *verifier)
- {
- // Any type is compatible with the unsuitable type.
- if (key == unsuitable_type)
- return true;
-
- if (key < reference_type || k.key < reference_type)
- return key == k.key;
-
- // The `null' type is convertible to any reference type.
- // FIXME: is this correct for THIS?
- if (key == null_type || k.key == null_type)
- return true;
-
- // 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$)
- return true;
-
- // An initialized type and an uninitialized type are not
- // compatible.
- if (isinitialized () != k.isinitialized ())
- return false;
-
- // Two uninitialized objects are compatible if either:
- // * The PCs are identical, or
- // * One PC is UNINIT.
- if (! isinitialized ())
- {
- if (pc != k.pc && pc != UNINIT && k.pc != UNINIT)
- 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);
- }
-
- bool isvoid () const
- {
- return key == void_type;
- }
-
- bool iswide () const
- {
- return key == long_type || key == double_type;
- }
-
- // Return number of stack or local variable slots taken by this
- // type.
- int depth () const
- {
- return iswide () ? 2 : 1;
- }
-
- bool isarray () const
- {
- // 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 false;
- }
-
- bool isnull () const
- {
- return key == null_type;
- }
-
- bool isinterface (_Jv_BytecodeVerifier *verifier)
- {
- resolve (verifier);
- if (key != reference_type)
- return false;
- return data.klass->isInterface ();
- }
-
- 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 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 ();
- if (k->isPrimitive ())
- return type (verifier->get_type_val_for_signature (k));
- return type (k);
- }
-
- // Return the array type corresponding to an initialized
- // reference. We could expand this to work for other kinds of
- // 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->getClassLoader ()));
- else
- verifier->verify_fail ("internal error in type::to_array()");
- }
-
- bool isreference () const
- {
- return key >= reference_type;
- }
-
- int get_pc () const
- {
- return pc;
- }
-
- bool isinitialized () const
- {
- return (key == reference_type
- || key == null_type
- || key == unresolved_reference_type);
- }
-
- bool isresolved () const
- {
- return (key == reference_type
- || key == null_type
- || key == uninitialized_reference_type);
- }
-
- 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 (ndims > 0)
- verifier->verify_fail ("array type has fewer dimensions than required");
- }
-
- // Merge OLD_TYPE into this. On error throw exception.
- bool merge (type& old_type, bool local_semantics,
- _Jv_BytecodeVerifier *verifier)
- {
- bool changed = false;
- bool refo = old_type.isreference ();
- bool refn = isreference ();
- if (refo && refn)
- {
- if (old_type.key == null_type)
- ;
- else if (key == null_type)
- {
- *this = old_type;
- changed = true;
- }
- else if (isinitialized () != old_type.isinitialized ())
- verifier->verify_fail ("merging initialized and uninitialized types");
- else
- {
- if (! isinitialized ())
- {
- if (pc == UNINIT)
- pc = old_type.pc;
- else if (old_type.pc == UNINIT)
- ;
- else if (pc != old_type.pc)
- verifier->verify_fail ("merging different uninitialized types");
- }
-
- if (! isresolved ()
- && ! old_type.isresolved ()
- && _Jv_equalUtf8Consts (data.name, old_type.data.name))
- {
- // 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 ();
- 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->getClassLoader();
- k = _Jv_GetArrayClass (k, loader);
- --arraycount;
- }
- data.klass = k;
- }
- }
- }
- }
- else if (refo || refn || key != old_type.key)
- {
- if (local_semantics)
- {
- // If we're merging into an "unused" slot, then we
- // simply accept whatever we're merging from.
- if (key == unused_by_subroutine_type)
- {
- *this = old_type;
- changed = true;
- }
- else if (old_type.key == unused_by_subroutine_type)
- {
- // Do nothing.
- }
- // If we already have an `unsuitable' type, then we
- // don't need to change again.
- else if (key != unsuitable_type)
- {
- key = unsuitable_type;
- changed = true;
- }
- }
- else
- verifier->verify_fail ("unmergeable type");
- }
- return changed;
- }
-
-#ifdef VERIFY_DEBUG
- void print (void) const
- {
- char c = '?';
- switch (key)
- {
- case boolean_type: c = 'Z'; break;
- case byte_type: c = 'B'; break;
- case char_type: c = 'C'; break;
- case short_type: c = 'S'; break;
- case int_type: c = 'I'; break;
- case long_type: c = 'J'; break;
- case float_type: c = 'F'; break;
- case double_type: c = 'D'; break;
- case void_type: c = 'V'; break;
- case unsuitable_type: c = '-'; break;
- case return_address_type: c = 'r'; break;
- case continuation_type: c = '+'; break;
- 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);
- }
-#endif /* VERIFY_DEBUG */
- };
-
- // This class holds all the state information we need for a given
- // location.
- struct state
- {
- // The current top of the stack, in terms of slots.
- int stacktop;
- // The current depth of the stack. This will be larger than
- // STACKTOP when wide types are on the stack.
- int stackdepth;
- // The stack.
- type *stack;
- // The local variables.
- type *locals;
- // This is used in subroutines to keep track of which local
- // variables have been accessed.
- bool *local_changed;
- // If not 0, then we are in a subroutine. The value is the PC of
- // the subroutine's entry point. We can use 0 as an exceptional
- // value because PC=0 can never be a subroutine.
- int subroutine;
- // This is used to keep a linked list of all the states which
- // require re-verification. We use the PC to keep track.
- int next;
- // We keep track of the type of `this' specially. This is used to
- // ensure that an instance initializer invokes another initializer
- // on `this' before returning. We must keep track of this
- // specially because otherwise we might be confused by code which
- // assigns to locals[0] (overwriting `this') and then returns
- // without really initializing.
- type this_type;
-
- // INVALID marks a state which is not on the linked list of states
- // requiring reverification.
- static const int INVALID = -1;
- // NO_NEXT marks the state at the end of the reverification list.
- static const int NO_NEXT = -2;
-
- // This is used to mark the stack depth at the instruction just
- // after a `jsr' when we haven't yet processed the corresponding
- // `ret'. See handle_jsr_insn for more information.
- static const int NO_STACK = -1;
-
- state ()
- : this_type ()
- {
- stack = NULL;
- locals = NULL;
- local_changed = NULL;
- }
-
- state (int max_stack, int max_locals)
- : this_type ()
- {
- stacktop = 0;
- stackdepth = 0;
- stack = new type[max_stack];
- for (int i = 0; i < max_stack; ++i)
- stack[i] = unsuitable_type;
- locals = new type[max_locals];
- local_changed = (bool *) _Jv_Malloc (sizeof (bool) * max_locals);
- for (int i = 0; i < max_locals; ++i)
- {
- locals[i] = unsuitable_type;
- local_changed[i] = false;
- }
- next = INVALID;
- subroutine = 0;
- }
-
- state (const state *orig, int max_stack, int max_locals,
- bool ret_semantics = false)
- {
- stack = new type[max_stack];
- locals = new type[max_locals];
- local_changed = (bool *) _Jv_Malloc (sizeof (bool) * max_locals);
- copy (orig, max_stack, max_locals, ret_semantics);
- next = INVALID;
- }
-
- ~state ()
- {
- if (stack)
- delete[] stack;
- if (locals)
- delete[] locals;
- if (local_changed)
- _Jv_Free (local_changed);
- }
-
- void *operator new[] (size_t bytes)
- {
- return _Jv_Malloc (bytes);
- }
-
- void operator delete[] (void *mem)
- {
- _Jv_Free (mem);
- }
-
- void *operator new (size_t bytes)
- {
- return _Jv_Malloc (bytes);
- }
-
- void operator delete (void *mem)
- {
- _Jv_Free (mem);
- }
-
- void copy (const state *copy, int max_stack, int max_locals,
- bool ret_semantics = false)
- {
- stacktop = copy->stacktop;
- stackdepth = copy->stackdepth;
- subroutine = copy->subroutine;
- for (int i = 0; i < max_stack; ++i)
- stack[i] = copy->stack[i];
- for (int i = 0; i < max_locals; ++i)
- {
- // See push_jump_merge to understand this case.
- if (ret_semantics)
- locals[i] = type (copy->local_changed[i]
- ? unsuitable_type
- : unused_by_subroutine_type);
- else
- locals[i] = copy->locals[i];
- local_changed[i] = copy->local_changed[i];
- }
- this_type = copy->this_type;
- // Don't modify `next'.
- }
-
- // Modify this state to reflect entry to an exception handler.
- void set_exception (type t, int max_stack)
- {
- stackdepth = 1;
- stacktop = 1;
- stack[0] = t;
- for (int i = stacktop; i < max_stack; ++i)
- stack[i] = unsuitable_type;
- }
-
- // Modify this state to reflect entry into a subroutine.
- void enter_subroutine (int npc, int max_locals)
- {
- subroutine = npc;
- // Mark all items as unchanged. Each subroutine needs to keep
- // track of its `changed' state independently. In the case of
- // nested subroutines, this information will be merged back into
- // parent by the `ret'.
- for (int i = 0; i < max_locals; ++i)
- local_changed[i] = false;
- }
-
- // Merge STATE_OLD into this state. Destructively modifies this
- // state. Returns true if the new state was in fact changed.
- // Will throw an exception if the states are not mergeable.
- bool merge (state *state_old, bool ret_semantics,
- int max_locals, _Jv_BytecodeVerifier *verifier)
- {
- bool changed = false;
-
- // Special handling for `this'. If one or the other is
- // uninitialized, then the merge is uninitialized.
- if (this_type.isinitialized ())
- this_type = state_old->this_type;
-
- // Merge subroutine states. Here we just keep track of what
- // subroutine we think we're in. We only check for a merge
- // (which is invalid) when we see a `ret'.
- if (subroutine == state_old->subroutine)
- {
- // Nothing.
- }
- else if (subroutine == 0)
- {
- subroutine = state_old->subroutine;
- changed = true;
- }
- else
- {
- // If the subroutines differ, indicate that the state
- // changed. This is needed to detect when subroutines have
- // merged.
- changed = true;
- }
-
- // Merge stacks. Special handling for NO_STACK case.
- if (state_old->stacktop == NO_STACK)
- {
- // Nothing to do in this case; we don't care about modifying
- // the old state.
- }
- else if (stacktop == NO_STACK)
- {
- stacktop = state_old->stacktop;
- stackdepth = state_old->stackdepth;
- for (int i = 0; i < stacktop; ++i)
- stack[i] = state_old->stack[i];
- changed = true;
- }
- else if (state_old->stacktop != stacktop)
- verifier->verify_fail ("stack sizes differ");
- else
- {
- for (int i = 0; i < state_old->stacktop; ++i)
- {
- if (stack[i].merge (state_old->stack[i], false, verifier))
- changed = true;
- }
- }
-
- // Merge local variables.
- for (int i = 0; i < max_locals; ++i)
- {
- // If we're not processing a `ret', then we merge every
- // local variable. If we are processing a `ret', then we
- // only merge locals which changed in the subroutine. When
- // processing a `ret', STATE_OLD is the state at the point
- // of the `ret', and THIS is the state just after the `jsr'.
- if (! ret_semantics || state_old->local_changed[i])
- {
- if (locals[i].merge (state_old->locals[i], true, verifier))
- {
- // Note that we don't call `note_variable' here.
- // This change doesn't represent a real change to a
- // local, but rather a merge artifact. If we're in
- // a subroutine which is called with two
- // incompatible types in a slot that is unused by
- // the subroutine, then we don't want to mark that
- // variable as having been modified.
- changed = true;
- }
- }
-
- // If we're in a subroutine, we must compute the union of
- // all the changed local variables.
- if (state_old->local_changed[i])
- note_variable (i);
- }
-
- return changed;
- }
-
- // Throw an exception if there is an uninitialized object on the
- // stack or in a local variable. EXCEPTION_SEMANTICS controls
- // whether we're using backwards-branch or exception-handing
- // semantics.
- void check_no_uninitialized_objects (int max_locals,
- _Jv_BytecodeVerifier *verifier,
- bool exception_semantics = false)
- {
- if (! exception_semantics)
- {
- for (int i = 0; i < stacktop; ++i)
- if (stack[i].isreference () && ! stack[i].isinitialized ())
- verifier->verify_fail ("uninitialized object on stack");
- }
-
- for (int i = 0; i < max_locals; ++i)
- if (locals[i].isreference () && ! locals[i].isinitialized ())
- verifier->verify_fail ("uninitialized object in local variable");
-
- check_this_initialized (verifier);
- }
-
- // Ensure that `this' has been initialized.
- void check_this_initialized (_Jv_BytecodeVerifier *verifier)
- {
- if (this_type.isreference () && ! this_type.isinitialized ())
- verifier->verify_fail ("`this' is uninitialized");
- }
-
- // Set type of `this'.
- void set_this_type (const type &k)
- {
- this_type = k;
- }
-
- // Note that a local variable was modified.
- void note_variable (int index)
- {
- if (subroutine > 0)
- local_changed[index] = true;
- }
-
- // Mark each `new'd object we know of that was allocated at PC as
- // initialized.
- void set_initialized (int pc, int max_locals)
- {
- for (int i = 0; i < stacktop; ++i)
- stack[i].set_initialized (pc);
- for (int i = 0; i < max_locals; ++i)
- locals[i].set_initialized (pc);
- this_type.set_initialized (pc);
- }
-
- // Return true if this state is the unmerged result of a `ret'.
- bool is_unmerged_ret_state (int max_locals) const
- {
- if (stacktop == NO_STACK)
- return true;
- for (int i = 0; i < max_locals; ++i)
- {
- if (locals[i].key == unused_by_subroutine_type)
- return true;
- }
- return false;
- }
-
-#ifdef VERIFY_DEBUG
- void print (const char *leader, int pc,
- int max_stack, int max_locals) const
- {
- debug_print ("%s [%4d]: [stack] ", leader, pc);
- int i;
- for (i = 0; i < stacktop; ++i)
- stack[i].print ();
- for (; i < max_stack; ++i)
- debug_print (".");
- debug_print (" [local] ");
- for (i = 0; i < max_locals; ++i)
- {
- locals[i].print ();
- debug_print (local_changed[i] ? "+" : " ");
- }
- if (subroutine == 0)
- debug_print (" | None");
- else
- debug_print (" | %4d", subroutine);
- debug_print (" | %p\n", this);
- }
-#else
- inline void print (const char *, int, int, int) const
- {
- }
-#endif /* VERIFY_DEBUG */
- };
-
- type pop_raw ()
- {
- if (current_state->stacktop <= 0)
- verify_fail ("stack empty");
- type r = current_state->stack[--current_state->stacktop];
- current_state->stackdepth -= r.depth ();
- if (current_state->stackdepth < 0)
- verify_fail ("stack empty", start_PC);
- return r;
- }
-
- type pop32 ()
- {
- type r = pop_raw ();
- if (r.iswide ())
- verify_fail ("narrow pop of wide type");
- return r;
- }
-
- type pop64 ()
- {
- type r = pop_raw ();
- if (! r.iswide ())
- verify_fail ("wide pop of narrow type");
- return r;
- }
-
- type pop_type (type match)
- {
- match.promote ();
- type t = pop_raw ();
- if (! match.compatible (t, this))
- verify_fail ("incompatible type on stack");
- return t;
- }
-
- // Pop a reference type or a return address.
- type pop_ref_or_return ()
- {
- type t = pop_raw ();
- if (! t.isreference () && t.key != return_address_type)
- verify_fail ("expected reference or return address on stack");
- return t;
- }
-
- void push_type (type t)
- {
- // If T is a numeric type like short, promote it to int.
- t.promote ();
-
- int depth = t.depth ();
- if (current_state->stackdepth + depth > current_method->max_stack)
- verify_fail ("stack overflow");
- current_state->stack[current_state->stacktop++] = t;
- current_state->stackdepth += depth;
- }
-
- void set_variable (int index, type t)
- {
- // If T is a numeric type like short, promote it to int.
- t.promote ();
-
- int depth = t.depth ();
- if (index > current_method->max_locals - depth)
- verify_fail ("invalid local variable");
- current_state->locals[index] = t;
- current_state->note_variable (index);
-
- if (depth == 2)
- {
- current_state->locals[index + 1] = continuation_type;
- current_state->note_variable (index + 1);
- }
- if (index > 0 && current_state->locals[index - 1].iswide ())
- {
- current_state->locals[index - 1] = unsuitable_type;
- // There's no need to call note_variable here.
- }
- }
-
- type get_variable (int index, type t)
- {
- int depth = t.depth ();
- if (index > current_method->max_locals - depth)
- verify_fail ("invalid local variable");
- if (! t.compatible (current_state->locals[index], this))
- verify_fail ("incompatible type in local variable");
- if (depth == 2)
- {
- type t (continuation_type);
- if (! current_state->locals[index + 1].compatible (t, this))
- verify_fail ("invalid local variable");
- }
- return current_state->locals[index];
- }
-
- // Make sure ARRAY is an array type and that its elements are
- // compatible with type ELEMENT. Returns the actual element type.
- type require_array_type (type array, type element)
- {
- // An odd case. Here we just pretend that everything went ok. If
- // the requested element type is some kind of reference, return
- // the null type instead.
- if (array.isnull ())
- return element.isreference () ? type (null_type) : element;
-
- if (! array.isarray ())
- verify_fail ("array required");
-
- type t = array.element_type (this);
- if (! element.compatible (t, this))
- {
- // Special case for byte arrays, which must also be boolean
- // arrays.
- bool ok = true;
- if (element.key == byte_type)
- {
- type e2 (boolean_type);
- ok = e2.compatible (t, this);
- }
- if (! ok)
- verify_fail ("incompatible array element type");
- }
-
- // Return T and not ELEMENT, because T might be specialized.
- return t;
- }
-
- jint get_byte ()
- {
- if (PC >= current_method->code_length)
- verify_fail ("premature end of bytecode");
- return (jint) bytecode[PC++] & 0xff;
- }
-
- jint get_ushort ()
- {
- jint b1 = get_byte ();
- jint b2 = get_byte ();
- return (jint) ((b1 << 8) | b2) & 0xffff;
- }
-
- jint get_short ()
- {
- jint b1 = get_byte ();
- jint b2 = get_byte ();
- jshort s = (b1 << 8) | b2;
- return (jint) s;
- }
-
- jint get_int ()
- {
- jint b1 = get_byte ();
- jint b2 = get_byte ();
- jint b3 = get_byte ();
- jint b4 = get_byte ();
- return (b1 << 24) | (b2 << 16) | (b3 << 8) | b4;
- }
-
- int compute_jump (int offset)
- {
- int npc = start_PC + offset;
- if (npc < 0 || npc >= current_method->code_length)
- verify_fail ("branch out of range", start_PC);
- return npc;
- }
-
- // Merge the indicated state into the state at the branch target and
- // schedule a new PC if there is a change. If RET_SEMANTICS is
- // true, then we are merging from a `ret' instruction into the
- // instruction after a `jsr'. This is a special case with its own
- // modified semantics.
- void push_jump_merge (int npc, state *nstate, bool ret_semantics = false)
- {
- bool changed = true;
- if (states[npc] == NULL)
- {
- // There's a weird situation here. If are examining the
- // branch that results from a `ret', and there is not yet a
- // state available at the branch target (the instruction just
- // after the `jsr'), then we have to construct a special kind
- // of state at that point for future merging. This special
- // state has the type `unused_by_subroutine_type' in each slot
- // which was not modified by the subroutine.
- states[npc] = new state (nstate, current_method->max_stack,
- current_method->max_locals, ret_semantics);
- debug_print ("== New state in push_jump_merge\n");
- states[npc]->print ("New", npc, current_method->max_stack,
- current_method->max_locals);
- }
- else
- {
- debug_print ("== Merge states in push_jump_merge\n");
- nstate->print ("Frm", start_PC, current_method->max_stack,
- current_method->max_locals);
- states[npc]->print (" To", npc, current_method->max_stack,
- current_method->max_locals);
- changed = states[npc]->merge (nstate, ret_semantics,
- current_method->max_locals, this);
- states[npc]->print ("New", npc, current_method->max_stack,
- current_method->max_locals);
- }
-
- if (changed && states[npc]->next == state::INVALID)
- {
- // The merge changed the state, and the new PC isn't yet on our
- // list of PCs to re-verify.
- states[npc]->next = next_verify_pc;
- next_verify_pc = npc;
- }
- }
-
- void push_jump (int offset)
- {
- int npc = compute_jump (offset);
- if (npc < PC)
- current_state->check_no_uninitialized_objects (current_method->max_locals, this);
- push_jump_merge (npc, current_state);
- }
-
- void push_exception_jump (type t, int pc)
- {
- current_state->check_no_uninitialized_objects (current_method->max_locals,
- this, true);
- state s (current_state, current_method->max_stack,
- current_method->max_locals);
- if (current_method->max_stack < 1)
- verify_fail ("stack overflow at exception handler");
- s.set_exception (t, current_method->max_stack);
- push_jump_merge (pc, &s);
- }
-
- int pop_jump ()
- {
- int *prev_loc = &next_verify_pc;
- int npc = next_verify_pc;
- bool skipped = false;
-
- while (npc != state::NO_NEXT)
- {
- // If the next available PC is an unmerged `ret' state, then
- // we aren't yet ready to handle it. That's because we would
- // need all kind of special cases to do so. So instead we
- // defer this jump until after we've processed it via a
- // fall-through. This has to happen because the instruction
- // before this one must be a `jsr'.
- if (! states[npc]->is_unmerged_ret_state (current_method->max_locals))
- {
- *prev_loc = states[npc]->next;
- states[npc]->next = state::INVALID;
- return npc;
- }
-
- skipped = true;
- prev_loc = &states[npc]->next;
- npc = states[npc]->next;
- }
-
- // Note that we might have gotten here even when there are
- // remaining states to process. That can happen if we find a
- // `jsr' without a `ret'.
- return state::NO_NEXT;
- }
-
- void invalidate_pc ()
- {
- PC = state::NO_NEXT;
- }
-
- void note_branch_target (int pc, bool is_jsr_target = false)
- {
- // Don't check `pc <= PC', because we've advanced PC after
- // fetching the target and we haven't yet checked the next
- // instruction.
- if (pc < PC && ! (flags[pc] & FLAG_INSN_START))
- verify_fail ("branch not to instruction start", start_PC);
- flags[pc] |= FLAG_BRANCH_TARGET;
- if (is_jsr_target)
- {
- // Record the jsr which called this instruction.
- subr_info *info = (subr_info *) _Jv_Malloc (sizeof (subr_info));
- info->pc = PC;
- info->next = jsr_ptrs[pc];
- jsr_ptrs[pc] = info;
- }
- }
-
- void skip_padding ()
- {
- while ((PC % 4) > 0)
- if (get_byte () != 0)
- verify_fail ("found nonzero padding byte");
- }
-
- // Return the subroutine to which the instruction at PC belongs.
- int get_subroutine (int pc)
- {
- if (states[pc] == NULL)
- return 0;
- return states[pc]->subroutine;
- }
-
- // Do the work for a `ret' instruction. INDEX is the index into the
- // local variables.
- void handle_ret_insn (int index)
- {
- get_variable (index, return_address_type);
-
- int csub = current_state->subroutine;
- if (csub == 0)
- verify_fail ("no subroutine");
-
- // Check to see if we've merged subroutines.
- subr_entry_info *entry;
- for (entry = entry_points; entry != NULL; entry = entry->next)
- {
- if (entry->ret_pc == start_PC)
- break;
- }
- if (entry == NULL)
- {
- entry = (subr_entry_info *) _Jv_Malloc (sizeof (subr_entry_info));
- entry->pc = csub;
- entry->ret_pc = start_PC;
- entry->next = entry_points;
- entry_points = entry;
- }
- else if (entry->pc != csub)
- verify_fail ("subroutines merged");
-
- for (subr_info *subr = jsr_ptrs[csub]; subr != NULL; subr = subr->next)
- {
- // Temporarily modify the current state so it looks like we're
- // in the enclosing context.
- current_state->subroutine = get_subroutine (subr->pc);
- if (subr->pc < PC)
- current_state->check_no_uninitialized_objects (current_method->max_locals, this);
- push_jump_merge (subr->pc, current_state, true);
- }
-
- current_state->subroutine = csub;
- invalidate_pc ();
- }
-
- // We're in the subroutine SUB, calling a subroutine at DEST. Make
- // sure this subroutine isn't already on the stack.
- void check_nonrecursive_call (int sub, int dest)
- {
- if (sub == 0)
- return;
- if (sub == dest)
- verify_fail ("recursive subroutine call");
- for (subr_info *info = jsr_ptrs[sub]; info != NULL; info = info->next)
- check_nonrecursive_call (get_subroutine (info->pc), dest);
- }
-
- void handle_jsr_insn (int offset)
- {
- int npc = compute_jump (offset);
-
- if (npc < PC)
- current_state->check_no_uninitialized_objects (current_method->max_locals, this);
- check_nonrecursive_call (current_state->subroutine, npc);
-
- // Modify our state as appropriate for entry into a subroutine.
- push_type (return_address_type);
- push_jump_merge (npc, current_state);
- // Clean up.
- pop_type (return_address_type);
-
- // On entry to the subroutine, the subroutine number must be set
- // and the locals must be marked as cleared. We do this after
- // merging state so that we don't erroneously "notice" a variable
- // change merely on entry.
- states[npc]->enter_subroutine (npc, current_method->max_locals);
-
- // Indicate that we don't know the stack depth of the instruction
- // following the `jsr'. The idea here is that we need to merge
- // the local variable state across the jsr, but the subroutine
- // might change the stack depth, so we can't make any assumptions
- // about it. So we have yet another special case. We know that
- // at this point PC points to the instruction after the jsr.
-
- // FIXME: what if we have a jsr at the end of the code, but that
- // jsr has no corresponding ret? Is this verifiable, or is it
- // not? If it is then we need a special case here.
- if (PC >= current_method->code_length)
- verify_fail ("fell off end");
-
- current_state->stacktop = state::NO_STACK;
- push_jump_merge (PC, current_state);
- invalidate_pc ();
- }
-
- jclass construct_primitive_array_type (type_val prim)
- {
- jclass k = NULL;
- switch (prim)
- {
- case boolean_type:
- k = JvPrimClass (boolean);
- break;
- case char_type:
- k = JvPrimClass (char);
- break;
- case float_type:
- k = JvPrimClass (float);
- break;
- case double_type:
- k = JvPrimClass (double);
- break;
- case byte_type:
- k = JvPrimClass (byte);
- break;
- case short_type:
- k = JvPrimClass (short);
- break;
- case int_type:
- k = JvPrimClass (int);
- break;
- case long_type:
- k = JvPrimClass (long);
- break;
- default:
- verify_fail ("unknown type in construct_primitive_array_type");
- }
- k = _Jv_GetArrayClass (k, NULL);
- return k;
- }
-
- // This pass computes the location of branch targets and also
- // instruction starts.
- void branch_prepass ()
- {
- flags = (char *) _Jv_Malloc (current_method->code_length);
- jsr_ptrs = (subr_info **) _Jv_Malloc (sizeof (subr_info *)
- * current_method->code_length);
-
- for (int i = 0; i < current_method->code_length; ++i)
- {
- flags[i] = 0;
- jsr_ptrs[i] = NULL;
- }
-
- bool last_was_jsr = false;
-
- PC = 0;
- while (PC < current_method->code_length)
- {
- // Set `start_PC' early so that error checking can have the
- // correct value.
- start_PC = PC;
- flags[PC] |= FLAG_INSN_START;
-
- // If the previous instruction was a jsr, then the next
- // instruction is a branch target -- the branch being the
- // corresponding `ret'.
- if (last_was_jsr)
- note_branch_target (PC);
- last_was_jsr = false;
-
- java_opcode opcode = (java_opcode) bytecode[PC++];
- switch (opcode)
- {
- case op_nop:
- case op_aconst_null:
- case op_iconst_m1:
- case op_iconst_0:
- case op_iconst_1:
- case op_iconst_2:
- case op_iconst_3:
- case op_iconst_4:
- case op_iconst_5:
- case op_lconst_0:
- case op_lconst_1:
- case op_fconst_0:
- case op_fconst_1:
- case op_fconst_2:
- case op_dconst_0:
- case op_dconst_1:
- case op_iload_0:
- case op_iload_1:
- case op_iload_2:
- case op_iload_3:
- case op_lload_0:
- case op_lload_1:
- case op_lload_2:
- case op_lload_3:
- case op_fload_0:
- case op_fload_1:
- case op_fload_2:
- case op_fload_3:
- case op_dload_0:
- case op_dload_1:
- case op_dload_2:
- case op_dload_3:
- case op_aload_0:
- case op_aload_1:
- case op_aload_2:
- case op_aload_3:
- case op_iaload:
- case op_laload:
- case op_faload:
- case op_daload:
- case op_aaload:
- case op_baload:
- case op_caload:
- case op_saload:
- case op_istore_0:
- case op_istore_1:
- case op_istore_2:
- case op_istore_3:
- case op_lstore_0:
- case op_lstore_1:
- case op_lstore_2:
- case op_lstore_3:
- case op_fstore_0:
- case op_fstore_1:
- case op_fstore_2:
- case op_fstore_3:
- case op_dstore_0:
- case op_dstore_1:
- case op_dstore_2:
- case op_dstore_3:
- case op_astore_0:
- case op_astore_1:
- case op_astore_2:
- case op_astore_3:
- case op_iastore:
- case op_lastore:
- case op_fastore:
- case op_dastore:
- case op_aastore:
- case op_bastore:
- case op_castore:
- case op_sastore:
- case op_pop:
- case op_pop2:
- case op_dup:
- case op_dup_x1:
- case op_dup_x2:
- case op_dup2:
- case op_dup2_x1:
- case op_dup2_x2:
- case op_swap:
- case op_iadd:
- case op_isub:
- case op_imul:
- case op_idiv:
- case op_irem:
- case op_ishl:
- case op_ishr:
- case op_iushr:
- case op_iand:
- case op_ior:
- case op_ixor:
- case op_ladd:
- case op_lsub:
- case op_lmul:
- case op_ldiv:
- case op_lrem:
- case op_lshl:
- case op_lshr:
- case op_lushr:
- case op_land:
- case op_lor:
- case op_lxor:
- case op_fadd:
- case op_fsub:
- case op_fmul:
- case op_fdiv:
- case op_frem:
- case op_dadd:
- case op_dsub:
- case op_dmul:
- case op_ddiv:
- case op_drem:
- case op_ineg:
- case op_i2b:
- case op_i2c:
- case op_i2s:
- case op_lneg:
- case op_fneg:
- case op_dneg:
- case op_i2l:
- case op_i2f:
- case op_i2d:
- case op_l2i:
- case op_l2f:
- case op_l2d:
- case op_f2i:
- case op_f2l:
- case op_f2d:
- case op_d2i:
- case op_d2l:
- case op_d2f:
- case op_lcmp:
- case op_fcmpl:
- case op_fcmpg:
- case op_dcmpl:
- case op_dcmpg:
- case op_monitorenter:
- case op_monitorexit:
- case op_ireturn:
- case op_lreturn:
- case op_freturn:
- case op_dreturn:
- case op_areturn:
- case op_return:
- case op_athrow:
- case op_arraylength:
- break;
-
- case op_bipush:
- case op_ldc:
- case op_iload:
- case op_lload:
- case op_fload:
- case op_dload:
- case op_aload:
- case op_istore:
- case op_lstore:
- case op_fstore:
- case op_dstore:
- case op_astore:
- case op_ret:
- case op_newarray:
- get_byte ();
- break;
-
- case op_iinc:
- case op_sipush:
- case op_ldc_w:
- case op_ldc2_w:
- case op_getstatic:
- case op_getfield:
- case op_putfield:
- case op_putstatic:
- case op_new:
- case op_anewarray:
- case op_instanceof:
- case op_checkcast:
- case op_invokespecial:
- case op_invokestatic:
- case op_invokevirtual:
- get_short ();
- break;
-
- case op_multianewarray:
- get_short ();
- get_byte ();
- break;
-
- case op_jsr:
- last_was_jsr = true;
- // Fall through.
- case op_ifeq:
- case op_ifne:
- case op_iflt:
- case op_ifge:
- case op_ifgt:
- case op_ifle:
- case op_if_icmpeq:
- case op_if_icmpne:
- case op_if_icmplt:
- case op_if_icmpge:
- case op_if_icmpgt:
- case op_if_icmple:
- case op_if_acmpeq:
- case op_if_acmpne:
- case op_ifnull:
- case op_ifnonnull:
- case op_goto:
- note_branch_target (compute_jump (get_short ()), last_was_jsr);
- break;
-
- case op_tableswitch:
- {
- skip_padding ();
- note_branch_target (compute_jump (get_int ()));
- jint low = get_int ();
- jint hi = get_int ();
- if (low > hi)
- verify_fail ("invalid tableswitch", start_PC);
- for (int i = low; i <= hi; ++i)
- note_branch_target (compute_jump (get_int ()));
- }
- break;
-
- case op_lookupswitch:
- {
- skip_padding ();
- note_branch_target (compute_jump (get_int ()));
- int npairs = get_int ();
- if (npairs < 0)
- verify_fail ("too few pairs in lookupswitch", start_PC);
- while (npairs-- > 0)
- {
- get_int ();
- note_branch_target (compute_jump (get_int ()));
- }
- }
- break;
-
- case op_invokeinterface:
- get_short ();
- get_byte ();
- get_byte ();
- break;
-
- case op_wide:
- {
- opcode = (java_opcode) get_byte ();
- get_short ();
- if (opcode == op_iinc)
- get_short ();
- }
- break;
-
- case op_jsr_w:
- last_was_jsr = true;
- // Fall through.
- case op_goto_w:
- note_branch_target (compute_jump (get_int ()), last_was_jsr);
- break;
-
- default:
- verify_fail ("unrecognized instruction in branch_prepass",
- start_PC);
- }
-
- // See if any previous branch tried to branch to the middle of
- // this instruction.
- for (int pc = start_PC + 1; pc < PC; ++pc)
- {
- if ((flags[pc] & FLAG_BRANCH_TARGET))
- verify_fail ("branch to middle of instruction", pc);
- }
- }
-
- // Verify exception handlers.
- for (int i = 0; i < current_method->exc_count; ++i)
- {
- if (! (flags[exception[i].handler_pc] & FLAG_INSN_START))
- verify_fail ("exception handler not at instruction start",
- exception[i].handler_pc);
- if (! (flags[exception[i].start_pc] & FLAG_INSN_START))
- verify_fail ("exception start not at instruction start",
- exception[i].start_pc);
- if (exception[i].end_pc != current_method->code_length
- && ! (flags[exception[i].end_pc] & FLAG_INSN_START))
- verify_fail ("exception end not at instruction start",
- exception[i].end_pc);
-
- flags[exception[i].handler_pc] |= FLAG_BRANCH_TARGET;
- }
- }
-
- void check_pool_index (int index)
- {
- if (index < 0 || index >= current_class->constants.size)
- verify_fail ("constant pool index out of range", start_PC);
- }
-
- type check_class_constant (int index)
- {
- check_pool_index (index);
- _Jv_Constants *pool = ¤t_class->constants;
- if (pool->tags[index] == JV_CONSTANT_ResolvedClass)
- return type (pool->data[index].clazz);
- else if (pool->tags[index] == JV_CONSTANT_Class)
- return type (pool->data[index].utf8);
- verify_fail ("expected class constant", start_PC);
- }
-
- type check_constant (int index)
- {
- check_pool_index (index);
- _Jv_Constants *pool = ¤t_class->constants;
- if (pool->tags[index] == JV_CONSTANT_ResolvedString
- || pool->tags[index] == JV_CONSTANT_String)
- return type (&java::lang::String::class$);
- else if (pool->tags[index] == JV_CONSTANT_Integer)
- return type (int_type);
- else if (pool->tags[index] == JV_CONSTANT_Float)
- return type (float_type);
- verify_fail ("String, int, or float constant expected", start_PC);
- }
-
- type check_wide_constant (int index)
- {
- check_pool_index (index);
- _Jv_Constants *pool = ¤t_class->constants;
- if (pool->tags[index] == JV_CONSTANT_Long)
- return type (long_type);
- else if (pool->tags[index] == JV_CONSTANT_Double)
- return type (double_type);
- verify_fail ("long or double constant expected", start_PC);
- }
-
- // Helper for both field and method. These are laid out the same in
- // the constant pool.
- type handle_field_or_method (int index, int expected,
- _Jv_Utf8Const **name,
- _Jv_Utf8Const **fmtype)
- {
- check_pool_index (index);
- _Jv_Constants *pool = ¤t_class->constants;
- if (pool->tags[index] != expected)
- verify_fail ("didn't see expected constant", start_PC);
- // Once we know we have a Fieldref or Methodref we assume that it
- // is correctly laid out in the constant pool. I think the code
- // in defineclass.cc guarantees this.
- _Jv_ushort class_index, name_and_type_index;
- _Jv_loadIndexes (&pool->data[index],
- class_index,
- name_and_type_index);
- _Jv_ushort name_index, desc_index;
- _Jv_loadIndexes (&pool->data[name_and_type_index],
- name_index, desc_index);
-
- *name = pool->data[name_index].utf8;
- *fmtype = pool->data[desc_index].utf8;
-
- return check_class_constant (class_index);
- }
-
- // Return field's type, compute class' type if requested.
- type check_field_constant (int index, type *class_type = NULL)
- {
- _Jv_Utf8Const *name, *field_type;
- type ct = handle_field_or_method (index,
- JV_CONSTANT_Fieldref,
- &name, &field_type);
- if (class_type)
- *class_type = ct;
- if (field_type->data[0] == '[' || field_type->data[0] == 'L')
- return type (field_type);
- return get_type_val_for_signature (field_type->data[0]);
- }
-
- type check_method_constant (int index, bool is_interface,
- _Jv_Utf8Const **method_name,
- _Jv_Utf8Const **method_signature)
- {
- return handle_field_or_method (index,
- (is_interface
- ? JV_CONSTANT_InterfaceMethodref
- : JV_CONSTANT_Methodref),
- method_name, method_signature);
- }
-
- type get_one_type (char *&p)
- {
- char *start = p;
-
- int arraycount = 0;
- while (*p == '[')
- {
- ++arraycount;
- ++p;
- }
-
- char v = *p++;
-
- if (v == 'L')
- {
- while (*p != ';')
- ++p;
- ++p;
- _Jv_Utf8Const *name = make_utf8_const (start, p - start);
- return type (name);
- }
-
- // Casting to jchar here is ok since we are looking at an ASCII
- // character.
- type_val rt = get_type_val_for_signature (jchar (v));
-
- if (arraycount == 0)
- {
- // Callers of this function eventually push their arguments on
- // the stack. So, promote them here.
- return type (rt).promote ();
- }
-
- jclass k = construct_primitive_array_type (rt);
- while (--arraycount > 0)
- k = _Jv_GetArrayClass (k, NULL);
- return type (k);
- }
-
- void compute_argument_types (_Jv_Utf8Const *signature,
- type *types)
- {
- char *p = signature->data;
- // Skip `('.
- ++p;
-
- int i = 0;
- while (*p != ')')
- types[i++] = get_one_type (p);
- }
-
- type compute_return_type (_Jv_Utf8Const *signature)
- {
- char *p = signature->data;
- while (*p != ')')
- ++p;
- ++p;
- return get_one_type (p);
- }
-
- void check_return_type (type onstack)
- {
- type rt = compute_return_type (current_method->self->signature);
- if (! rt.compatible (onstack, this))
- verify_fail ("incompatible return type");
- }
-
- // Initialize the stack for the new method. Returns true if this
- // method is an instance initializer.
- bool initialize_stack ()
- {
- int var = 0;
- bool is_init = false;
-
- using namespace java::lang::reflect;
- if (! Modifier::isStatic (current_method->self->accflags))
- {
- type kurr (current_class);
- if (_Jv_equalUtf8Consts (current_method->self->name, gcj::init_name))
- {
- kurr.set_uninitialized (type::SELF, this);
- is_init = true;
- }
- set_variable (0, kurr);
- current_state->set_this_type (kurr);
- ++var;
- }
-
- // We have to handle wide arguments specially here.
- int arg_count = _Jv_count_arguments (current_method->self->signature);
- type arg_types[arg_count];
- compute_argument_types (current_method->self->signature, arg_types);
- for (int i = 0; i < arg_count; ++i)
- {
- set_variable (var, arg_types[i]);
- ++var;
- if (arg_types[i].iswide ())
- ++var;
- }
-
- return is_init;
- }
-
- void verify_instructions_0 ()
- {
- current_state = new state (current_method->max_stack,
- current_method->max_locals);
-
- PC = 0;
- start_PC = 0;
-
- // True if we are verifying an instance initializer.
- bool this_is_init = initialize_stack ();
-
- states = (state **) _Jv_Malloc (sizeof (state *)
- * current_method->code_length);
- for (int i = 0; i < current_method->code_length; ++i)
- states[i] = NULL;
-
- next_verify_pc = state::NO_NEXT;
-
- while (true)
- {
- // If the PC was invalidated, get a new one from the work list.
- if (PC == state::NO_NEXT)
- {
- PC = pop_jump ();
- if (PC == state::INVALID)
- verify_fail ("can't happen: saw state::INVALID");
- if (PC == state::NO_NEXT)
- break;
- debug_print ("== State pop from pending list\n");
- // Set up the current state.
- current_state->copy (states[PC], current_method->max_stack,
- current_method->max_locals);
- }
- else
- {
- // Control can't fall off the end of the bytecode. We
- // only need to check this in the fall-through case,
- // because branch bounds are checked when they are
- // pushed.
- if (PC >= current_method->code_length)
- verify_fail ("fell off end");
-
- // We only have to do this checking in the situation where
- // control flow falls through from the previous
- // instruction. Otherwise merging is done at the time we
- // push the branch.
- if (states[PC] != NULL)
- {
- // We've already visited this instruction. So merge
- // the states together. If this yields no change then
- // we don't have to re-verify. However, if the new
- // state is an the result of an unmerged `ret', we
- // must continue through it.
- debug_print ("== Fall through merge\n");
- states[PC]->print ("Old", PC, current_method->max_stack,
- current_method->max_locals);
- current_state->print ("Cur", PC, current_method->max_stack,
- current_method->max_locals);
- if (! current_state->merge (states[PC], false,
- current_method->max_locals, this)
- && ! states[PC]->is_unmerged_ret_state (current_method->max_locals))
- {
- debug_print ("== Fall through optimization\n");
- invalidate_pc ();
- continue;
- }
- // Save a copy of it for later.
- states[PC]->copy (current_state, current_method->max_stack,
- current_method->max_locals);
- current_state->print ("New", PC, current_method->max_stack,
- current_method->max_locals);
- }
- }
-
- // We only have to keep saved state at branch targets. If
- // we're at a branch target and the state here hasn't been set
- // yet, we set it now.
- if (states[PC] == NULL && (flags[PC] & FLAG_BRANCH_TARGET))
- {
- states[PC] = new state (current_state, current_method->max_stack,
- current_method->max_locals);
- }
-
- // Set this before handling exceptions so that debug output is
- // sane.
- start_PC = PC;
-
- // Update states for all active exception handlers. Ordinarily
- // there are not many exception handlers. So we simply run
- // through them all.
- for (int i = 0; i < current_method->exc_count; ++i)
- {
- if (PC >= exception[i].start_pc && PC < exception[i].end_pc)
- {
- type handler (&java::lang::Throwable::class$);
- if (exception[i].handler_type != 0)
- handler = check_class_constant (exception[i].handler_type);
- push_exception_jump (handler, exception[i].handler_pc);
- }
- }
-
- current_state->print (" ", PC, current_method->max_stack,
- current_method->max_locals);
- java_opcode opcode = (java_opcode) bytecode[PC++];
- switch (opcode)
- {
- case op_nop:
- break;
-
- case op_aconst_null:
- push_type (null_type);
- break;
-
- case op_iconst_m1:
- case op_iconst_0:
- case op_iconst_1:
- case op_iconst_2:
- case op_iconst_3:
- case op_iconst_4:
- case op_iconst_5:
- push_type (int_type);
- break;
-
- case op_lconst_0:
- case op_lconst_1:
- push_type (long_type);
- break;
-
- case op_fconst_0:
- case op_fconst_1:
- case op_fconst_2:
- push_type (float_type);
- break;
-
- case op_dconst_0:
- case op_dconst_1:
- push_type (double_type);
- break;
-
- case op_bipush:
- get_byte ();
- push_type (int_type);
- break;
-
- case op_sipush:
- get_short ();
- push_type (int_type);
- break;
-
- case op_ldc:
- push_type (check_constant (get_byte ()));
- break;
- case op_ldc_w:
- push_type (check_constant (get_ushort ()));
- break;
- case op_ldc2_w:
- push_type (check_wide_constant (get_ushort ()));
- break;
-
- case op_iload:
- push_type (get_variable (get_byte (), int_type));
- break;
- case op_lload:
- push_type (get_variable (get_byte (), long_type));
- break;
- case op_fload:
- push_type (get_variable (get_byte (), float_type));
- break;
- case op_dload:
- push_type (get_variable (get_byte (), double_type));
- break;
- case op_aload:
- push_type (get_variable (get_byte (), reference_type));
- break;
-
- case op_iload_0:
- case op_iload_1:
- case op_iload_2:
- case op_iload_3:
- push_type (get_variable (opcode - op_iload_0, int_type));
- break;
- case op_lload_0:
- case op_lload_1:
- case op_lload_2:
- case op_lload_3:
- push_type (get_variable (opcode - op_lload_0, long_type));
- break;
- case op_fload_0:
- case op_fload_1:
- case op_fload_2:
- case op_fload_3:
- push_type (get_variable (opcode - op_fload_0, float_type));
- break;
- case op_dload_0:
- case op_dload_1:
- case op_dload_2:
- case op_dload_3:
- push_type (get_variable (opcode - op_dload_0, double_type));
- break;
- case op_aload_0:
- case op_aload_1:
- case op_aload_2:
- case op_aload_3:
- push_type (get_variable (opcode - op_aload_0, reference_type));
- break;
- case op_iaload:
- pop_type (int_type);
- push_type (require_array_type (pop_type (reference_type),
- int_type));
- break;
- case op_laload:
- pop_type (int_type);
- push_type (require_array_type (pop_type (reference_type),
- long_type));
- break;
- case op_faload:
- pop_type (int_type);
- push_type (require_array_type (pop_type (reference_type),
- float_type));
- break;
- case op_daload:
- pop_type (int_type);
- push_type (require_array_type (pop_type (reference_type),
- double_type));
- break;
- case op_aaload:
- pop_type (int_type);
- push_type (require_array_type (pop_type (reference_type),
- reference_type));
- break;
- case op_baload:
- pop_type (int_type);
- require_array_type (pop_type (reference_type), byte_type);
- push_type (int_type);
- break;
- case op_caload:
- pop_type (int_type);
- require_array_type (pop_type (reference_type), char_type);
- push_type (int_type);
- break;
- case op_saload:
- pop_type (int_type);
- require_array_type (pop_type (reference_type), short_type);
- push_type (int_type);
- break;
- case op_istore:
- set_variable (get_byte (), pop_type (int_type));
- break;
- case op_lstore:
- set_variable (get_byte (), pop_type (long_type));
- break;
- case op_fstore:
- set_variable (get_byte (), pop_type (float_type));
- break;
- case op_dstore:
- set_variable (get_byte (), pop_type (double_type));
- break;
- case op_astore:
- set_variable (get_byte (), pop_ref_or_return ());
- break;
- case op_istore_0:
- case op_istore_1:
- case op_istore_2:
- case op_istore_3:
- set_variable (opcode - op_istore_0, pop_type (int_type));
- break;
- case op_lstore_0:
- case op_lstore_1:
- case op_lstore_2:
- case op_lstore_3:
- set_variable (opcode - op_lstore_0, pop_type (long_type));
- break;
- case op_fstore_0:
- case op_fstore_1:
- case op_fstore_2:
- case op_fstore_3:
- set_variable (opcode - op_fstore_0, pop_type (float_type));
- break;
- case op_dstore_0:
- case op_dstore_1:
- case op_dstore_2:
- case op_dstore_3:
- set_variable (opcode - op_dstore_0, pop_type (double_type));
- break;
- case op_astore_0:
- case op_astore_1:
- case op_astore_2:
- case op_astore_3:
- set_variable (opcode - op_astore_0, pop_ref_or_return ());
- break;
- case op_iastore:
- pop_type (int_type);
- pop_type (int_type);
- require_array_type (pop_type (reference_type), int_type);
- break;
- case op_lastore:
- pop_type (long_type);
- pop_type (int_type);
- require_array_type (pop_type (reference_type), long_type);
- break;
- case op_fastore:
- pop_type (float_type);
- pop_type (int_type);
- require_array_type (pop_type (reference_type), float_type);
- break;
- case op_dastore:
- pop_type (double_type);
- pop_type (int_type);
- require_array_type (pop_type (reference_type), double_type);
- break;
- case op_aastore:
- pop_type (reference_type);
- pop_type (int_type);
- require_array_type (pop_type (reference_type), reference_type);
- break;
- case op_bastore:
- pop_type (int_type);
- pop_type (int_type);
- require_array_type (pop_type (reference_type), byte_type);
- break;
- case op_castore:
- pop_type (int_type);
- pop_type (int_type);
- require_array_type (pop_type (reference_type), char_type);
- break;
- case op_sastore:
- pop_type (int_type);
- pop_type (int_type);
- require_array_type (pop_type (reference_type), short_type);
- break;
- case op_pop:
- pop32 ();
- break;
- case op_pop2:
- pop64 ();
- break;
- case op_dup:
- {
- type t = pop32 ();
- push_type (t);
- push_type (t);
- }
- break;
- case op_dup_x1:
- {
- type t1 = pop32 ();
- type t2 = pop32 ();
- push_type (t1);
- push_type (t2);
- push_type (t1);
- }
- break;
- case op_dup_x2:
- {
- type t1 = pop32 ();
- type t2 = pop_raw ();
- if (! t2.iswide ())
- {
- type t3 = pop32 ();
- push_type (t1);
- push_type (t3);
- }
- else
- push_type (t1);
- push_type (t2);
- push_type (t1);
- }
- break;
- case op_dup2:
- {
- type t = pop_raw ();
- if (! t.iswide ())
- {
- type t2 = pop32 ();
- push_type (t2);
- push_type (t);
- push_type (t2);
- }
- else
- push_type (t);
- push_type (t);
- }
- break;
- case op_dup2_x1:
- {
- type t1 = pop_raw ();
- type t2 = pop32 ();
- if (! t1.iswide ())
- {
- type t3 = pop32 ();
- push_type (t2);
- push_type (t1);
- push_type (t3);
- }
- else
- push_type (t1);
- push_type (t2);
- push_type (t1);
- }
- break;
- case op_dup2_x2:
- {
- type t1 = pop_raw ();
- if (t1.iswide ())
- {
- type t2 = pop_raw ();
- if (t2.iswide ())
- {
- push_type (t1);
- push_type (t2);
- }
- else
- {
- type t3 = pop32 ();
- push_type (t1);
- push_type (t3);
- push_type (t2);
- }
- push_type (t1);
- }
- else
- {
- type t2 = pop32 ();
- type t3 = pop_raw ();
- if (t3.iswide ())
- {
- push_type (t2);
- push_type (t1);
- }
- else
- {
- type t4 = pop32 ();
- push_type (t2);
- push_type (t1);
- push_type (t4);
- }
- push_type (t3);
- push_type (t2);
- push_type (t1);
- }
- }
- break;
- case op_swap:
- {
- type t1 = pop32 ();
- type t2 = pop32 ();
- push_type (t1);
- push_type (t2);
- }
- break;
- case op_iadd:
- case op_isub:
- case op_imul:
- case op_idiv:
- case op_irem:
- case op_ishl:
- case op_ishr:
- case op_iushr:
- case op_iand:
- case op_ior:
- case op_ixor:
- pop_type (int_type);
- push_type (pop_type (int_type));
- break;
- case op_ladd:
- case op_lsub:
- case op_lmul:
- case op_ldiv:
- case op_lrem:
- case op_land:
- case op_lor:
- case op_lxor:
- pop_type (long_type);
- push_type (pop_type (long_type));
- break;
- case op_lshl:
- case op_lshr:
- case op_lushr:
- pop_type (int_type);
- push_type (pop_type (long_type));
- break;
- case op_fadd:
- case op_fsub:
- case op_fmul:
- case op_fdiv:
- case op_frem:
- pop_type (float_type);
- push_type (pop_type (float_type));
- break;
- case op_dadd:
- case op_dsub:
- case op_dmul:
- case op_ddiv:
- case op_drem:
- pop_type (double_type);
- push_type (pop_type (double_type));
- break;
- case op_ineg:
- case op_i2b:
- case op_i2c:
- case op_i2s:
- push_type (pop_type (int_type));
- break;
- case op_lneg:
- push_type (pop_type (long_type));
- break;
- case op_fneg:
- push_type (pop_type (float_type));
- break;
- case op_dneg:
- push_type (pop_type (double_type));
- break;
- case op_iinc:
- get_variable (get_byte (), int_type);
- get_byte ();
- break;
- case op_i2l:
- pop_type (int_type);
- push_type (long_type);
- break;
- case op_i2f:
- pop_type (int_type);
- push_type (float_type);
- break;
- case op_i2d:
- pop_type (int_type);
- push_type (double_type);
- break;
- case op_l2i:
- pop_type (long_type);
- push_type (int_type);
- break;
- case op_l2f:
- pop_type (long_type);
- push_type (float_type);
- break;
- case op_l2d:
- pop_type (long_type);
- push_type (double_type);
- break;
- case op_f2i:
- pop_type (float_type);
- push_type (int_type);
- break;
- case op_f2l:
- pop_type (float_type);
- push_type (long_type);
- break;
- case op_f2d:
- pop_type (float_type);
- push_type (double_type);
- break;
- case op_d2i:
- pop_type (double_type);
- push_type (int_type);
- break;
- case op_d2l:
- pop_type (double_type);
- push_type (long_type);
- break;
- case op_d2f:
- pop_type (double_type);
- push_type (float_type);
- break;
- case op_lcmp:
- pop_type (long_type);
- pop_type (long_type);
- push_type (int_type);
- break;
- case op_fcmpl:
- case op_fcmpg:
- pop_type (float_type);
- pop_type (float_type);
- push_type (int_type);
- break;
- case op_dcmpl:
- case op_dcmpg:
- pop_type (double_type);
- pop_type (double_type);
- push_type (int_type);
- break;
- case op_ifeq:
- case op_ifne:
- case op_iflt:
- case op_ifge:
- case op_ifgt:
- case op_ifle:
- pop_type (int_type);
- push_jump (get_short ());
- break;
- case op_if_icmpeq:
- case op_if_icmpne:
- case op_if_icmplt:
- case op_if_icmpge:
- case op_if_icmpgt:
- case op_if_icmple:
- pop_type (int_type);
- pop_type (int_type);
- push_jump (get_short ());
- break;
- case op_if_acmpeq:
- case op_if_acmpne:
- pop_type (reference_type);
- pop_type (reference_type);
- push_jump (get_short ());
- break;
- case op_goto:
- push_jump (get_short ());
- invalidate_pc ();
- break;
- case op_jsr:
- handle_jsr_insn (get_short ());
- break;
- case op_ret:
- handle_ret_insn (get_byte ());
- break;
- case op_tableswitch:
- {
- pop_type (int_type);
- skip_padding ();
- push_jump (get_int ());
- jint low = get_int ();
- jint high = get_int ();
- // Already checked LOW -vs- HIGH.
- for (int i = low; i <= high; ++i)
- push_jump (get_int ());
- invalidate_pc ();
- }
- break;
-
- case op_lookupswitch:
- {
- pop_type (int_type);
- skip_padding ();
- push_jump (get_int ());
- jint npairs = get_int ();
- // Already checked NPAIRS >= 0.
- jint lastkey = 0;
- for (int i = 0; i < npairs; ++i)
- {
- jint key = get_int ();
- if (i > 0 && key <= lastkey)
- verify_fail ("lookupswitch pairs unsorted", start_PC);
- lastkey = key;
- push_jump (get_int ());
- }
- invalidate_pc ();
- }
- break;
- case op_ireturn:
- check_return_type (pop_type (int_type));
- invalidate_pc ();
- break;
- case op_lreturn:
- check_return_type (pop_type (long_type));
- invalidate_pc ();
- break;
- case op_freturn:
- check_return_type (pop_type (float_type));
- invalidate_pc ();
- break;
- case op_dreturn:
- check_return_type (pop_type (double_type));
- invalidate_pc ();
- break;
- case op_areturn:
- check_return_type (pop_type (reference_type));
- invalidate_pc ();
- break;
- case op_return:
- // We only need to check this when the return type is
- // void, because all instance initializers return void.
- if (this_is_init)
- current_state->check_this_initialized (this);
- check_return_type (void_type);
- invalidate_pc ();
- break;
- case op_getstatic:
- push_type (check_field_constant (get_ushort ()));
- break;
- case op_putstatic:
- pop_type (check_field_constant (get_ushort ()));
- break;
- case op_getfield:
- {
- type klass;
- type field = check_field_constant (get_ushort (), &klass);
- pop_type (klass);
- push_type (field);
- }
- break;
- case op_putfield:
- {
- type klass;
- type field = check_field_constant (get_ushort (), &klass);
- pop_type (field);
-
- // We have an obscure special case here: we can use
- // `putfield' on a field declared in this class, even if
- // `this' has not yet been initialized.
- if (! current_state->this_type.isinitialized ()
- && current_state->this_type.pc == type::SELF)
- klass.set_uninitialized (type::SELF, this);
- pop_type (klass);
- }
- break;
-
- case op_invokevirtual:
- case op_invokespecial:
- case op_invokestatic:
- case op_invokeinterface:
- {
- _Jv_Utf8Const *method_name, *method_signature;
- type class_type
- = check_method_constant (get_ushort (),
- opcode == op_invokeinterface,
- &method_name,
- &method_signature);
- // NARGS is only used when we're processing
- // invokeinterface. It is simplest for us to compute it
- // here and then verify it later.
- int nargs = 0;
- if (opcode == op_invokeinterface)
- {
- nargs = get_byte ();
- if (get_byte () != 0)
- verify_fail ("invokeinterface dummy byte is wrong");
- }
-
- bool is_init = false;
- if (_Jv_equalUtf8Consts (method_name, gcj::init_name))
- {
- is_init = true;
- if (opcode != op_invokespecial)
- verify_fail ("can't invoke <init>");
- }
- else if (method_name->data[0] == '<')
- verify_fail ("can't invoke method starting with `<'");
-
- // Pop arguments and check types.
- int arg_count = _Jv_count_arguments (method_signature);
- type arg_types[arg_count];
- compute_argument_types (method_signature, arg_types);
- for (int i = arg_count - 1; i >= 0; --i)
- {
- // This is only used for verifying the byte for
- // invokeinterface.
- nargs -= arg_types[i].depth ();
- pop_type (arg_types[i]);
- }
-
- if (opcode == op_invokeinterface
- && nargs != 1)
- verify_fail ("wrong argument count for invokeinterface");
-
- if (opcode != op_invokestatic)
- {
- type t = class_type;
- if (is_init)
- {
- // In this case the PC doesn't matter.
- t.set_uninitialized (type::UNINIT, this);
- }
- type raw = pop_raw ();
- bool ok = false;
- 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)
- verify_fail ("incompatible type on stack");
-
- if (is_init)
- current_state->set_initialized (raw.get_pc (),
- current_method->max_locals);
- }
-
- type rt = compute_return_type (method_signature);
- if (! rt.isvoid ())
- push_type (rt);
- }
- break;
-
- case op_new:
- {
- type t = check_class_constant (get_ushort ());
- if (t.isarray () || t.isinterface (this) || t.isabstract (this))
- verify_fail ("type is array, interface, or abstract");
- t.set_uninitialized (start_PC, this);
- push_type (t);
- }
- break;
-
- case op_newarray:
- {
- int atype = get_byte ();
- // We intentionally have chosen constants to make this
- // valid.
- 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)));
- }
- break;
- case op_anewarray:
- pop_type (int_type);
- push_type (check_class_constant (get_ushort ()).to_array (this));
- break;
- case op_arraylength:
- {
- type t = pop_type (reference_type);
- if (! t.isarray () && ! t.isnull ())
- verify_fail ("array type expected");
- push_type (int_type);
- }
- break;
- case op_athrow:
- pop_type (type (&java::lang::Throwable::class$));
- invalidate_pc ();
- break;
- case op_checkcast:
- pop_type (reference_type);
- push_type (check_class_constant (get_ushort ()));
- break;
- case op_instanceof:
- pop_type (reference_type);
- check_class_constant (get_ushort ());
- push_type (int_type);
- break;
- case op_monitorenter:
- pop_type (reference_type);
- break;
- case op_monitorexit:
- pop_type (reference_type);
- break;
- case op_wide:
- {
- switch (get_byte ())
- {
- case op_iload:
- push_type (get_variable (get_ushort (), int_type));
- break;
- case op_lload:
- push_type (get_variable (get_ushort (), long_type));
- break;
- case op_fload:
- push_type (get_variable (get_ushort (), float_type));
- break;
- case op_dload:
- push_type (get_variable (get_ushort (), double_type));
- break;
- case op_aload:
- push_type (get_variable (get_ushort (), reference_type));
- break;
- case op_istore:
- set_variable (get_ushort (), pop_type (int_type));
- break;
- case op_lstore:
- set_variable (get_ushort (), pop_type (long_type));
- break;
- case op_fstore:
- set_variable (get_ushort (), pop_type (float_type));
- break;
- case op_dstore:
- set_variable (get_ushort (), pop_type (double_type));
- break;
- case op_astore:
- set_variable (get_ushort (), pop_type (reference_type));
- break;
- case op_ret:
- handle_ret_insn (get_short ());
- break;
- case op_iinc:
- get_variable (get_ushort (), int_type);
- get_short ();
- break;
- default:
- verify_fail ("unrecognized wide instruction", start_PC);
- }
- }
- break;
- case op_multianewarray:
- {
- type atype = check_class_constant (get_ushort ());
- int dim = get_byte ();
- if (dim < 1)
- verify_fail ("too few dimensions to multianewarray", start_PC);
- atype.verify_dimensions (dim, this);
- for (int i = 0; i < dim; ++i)
- pop_type (int_type);
- push_type (atype);
- }
- break;
- case op_ifnull:
- case op_ifnonnull:
- pop_type (reference_type);
- push_jump (get_short ());
- break;
- case op_goto_w:
- push_jump (get_int ());
- invalidate_pc ();
- break;
- case op_jsr_w:
- handle_jsr_insn (get_int ());
- break;
-
- default:
- // Unrecognized opcode.
- verify_fail ("unrecognized instruction in verify_instructions_0",
- start_PC);
- }
- }
- }
-
- __attribute__ ((__noreturn__)) void verify_fail (char *s, jint pc = -1)
- {
- using namespace java::lang;
- StringBuffer *buf = new StringBuffer ();
-
- buf->append (JvNewStringLatin1 ("verification failed"));
- if (pc == -1)
- pc = start_PC;
- if (pc != -1)
- {
- buf->append (JvNewStringLatin1 (" at PC "));
- buf->append (pc);
- }
-
- _Jv_InterpMethod *method = current_method;
- buf->append (JvNewStringLatin1 (" in "));
- buf->append (current_class->getName());
- buf->append ((jchar) ':');
- buf->append (JvNewStringUTF (method->get_method()->name->data));
- buf->append ((jchar) '(');
- buf->append (JvNewStringUTF (method->get_method()->signature->data));
- buf->append ((jchar) ')');
-
- buf->append (JvNewStringLatin1 (": "));
- buf->append (JvNewStringLatin1 (s));
- throw new java::lang::VerifyError (buf->toString ());
- }
-
-public:
-
- void verify_instructions ()
- {
- branch_prepass ();
- verify_instructions_0 ();
- }
-
- _Jv_BytecodeVerifier (_Jv_InterpMethod *m)
- {
- // We just print the text as utf-8. This is just for debugging
- // anyway.
- debug_print ("--------------------------------\n");
- debug_print ("-- Verifying method `%s'\n", m->self->name->data);
-
- current_method = m;
- bytecode = m->bytecode ();
- exception = m->exceptions ();
- current_class = m->defining_class;
-
- states = NULL;
- flags = NULL;
- jsr_ptrs = NULL;
- utf8_list = NULL;
- entry_points = NULL;
- }
-
- ~_Jv_BytecodeVerifier ()
- {
- if (states)
- _Jv_Free (states);
- if (flags)
- _Jv_Free (flags);
-
- if (jsr_ptrs)
- {
- for (int i = 0; i < current_method->code_length; ++i)
- {
- if (jsr_ptrs[i] != NULL)
- {
- subr_info *info = jsr_ptrs[i];
- while (info != NULL)
- {
- subr_info *next = info->next;
- _Jv_Free (info);
- info = next;
- }
- }
- }
- _Jv_Free (jsr_ptrs);
- }
-
- while (utf8_list != NULL)
- {
- linked_utf8 *n = utf8_list->next;
- _Jv_Free (utf8_list->val);
- _Jv_Free (utf8_list);
- utf8_list = n;
- }
-
- while (entry_points != NULL)
- {
- subr_entry_info *next = entry_points->next;
- _Jv_Free (entry_points);
- entry_points = next;
- }
- }
-};
-
-void
-_Jv_VerifyMethod (_Jv_InterpMethod *meth)
-{
- _Jv_BytecodeVerifier v (meth);
- v.verify_instructions ();
-}
-#endif /* INTERPRETER */
projects / msp430-gcc.git / blobdiff