/* A free-list of unused permanent TREE_LIST nodes. */
static GTY((deletable)) tree tree_list_free_list;
+/* The physical memory page size used in this computer. See
+ build_field_ref(). */
+static GTY(()) tree page_size;
+
/* The stack pointer of the Java virtual machine.
This does include the size of the quick_stack. */
constant_value = build_int_cst (NULL_TREE, ival);
res = fold_build2 (PLUS_EXPR, int_type_node, local_var, constant_value);
java_add_stmt (build2 (MODIFY_EXPR, TREE_TYPE (local_var), local_var, res));
- update_aliases (local_var, local_var_index, pc);
}
}
else
{
- int check = (flag_check_references
- && ! (DECL_P (self_value)
- && DECL_NAME (self_value) == this_identifier_node));
-
tree base_type = promote_type (base_class);
+
+ /* CHECK is true if self_value is not the this pointer. */
+ int check = (! (DECL_P (self_value)
+ && DECL_NAME (self_value) == this_identifier_node));
+
+ /* Determine whether a field offset from NULL will lie within
+ Page 0: this is necessary on those GNU/Linux/BSD systems that
+ trap SEGV to generate NullPointerExceptions.
+
+ We assume that Page 0 will be mapped with NOPERM, and that
+ memory may be allocated from any other page, so only field
+ offsets < pagesize are guaranteed to trap. We also assume
+ the smallest page size we'll encounter is 4k bytes. */
+ if (! flag_syntax_only && check && ! flag_check_references
+ && ! flag_indirect_dispatch)
+ {
+ tree field_offset = byte_position (field_decl);
+ if (! page_size)
+ page_size = size_int (4096);
+ check = ! INT_CST_LT_UNSIGNED (field_offset, page_size);
+ }
+
if (base_type != TREE_TYPE (self_value))
self_value = fold_build1 (NOP_EXPR, base_type, self_value);
if (! flag_syntax_only && flag_indirect_dispatch)
{
tree otable_index
= build_int_cst (NULL_TREE, get_symbol_table_index
- (field_decl, &TYPE_OTABLE_METHODS (output_class)));
+ (field_decl, NULL_TREE,
+ &TYPE_OTABLE_METHODS (output_class)));
tree field_offset
= build4 (ARRAY_REF, integer_type_node,
TYPE_OTABLE_DECL (output_class), otable_index,
field_offset);
field_offset = fold (convert (sizetype, field_offset));
+ self_value = java_check_reference (self_value, check);
address
= fold_build2 (PLUS_EXPR,
build_pointer_type (TREE_TYPE (field_decl)),
return init;
}
+\f
+
+/* Rewrite expensive calls that require stack unwinding at runtime to
+ cheaper alternatives. The logic here performs these
+ transformations:
+
+ java.lang.Class.forName("foo") -> java.lang.Class.forName("foo", class$)
+ java.lang.Class.getClassLoader() -> java.lang.Class.getClassLoader(class$)
+
+*/
+
+typedef struct
+{
+ const char *classname;
+ const char *method;
+ const char *signature;
+ const char *new_signature;
+ int flags;
+ tree (*rewrite_arglist) (tree arglist);
+} rewrite_rule;
+
+/* Add this.class to the end of an arglist. */
+
+static tree
+rewrite_arglist_getclass (tree arglist)
+{
+ return chainon (arglist,
+ tree_cons (NULL_TREE, build_class_ref (output_class), NULL_TREE));
+}
+
+static rewrite_rule rules[] =
+ {{"java.lang.Class", "getClassLoader", "()Ljava/lang/ClassLoader;",
+ "(Ljava/lang/Class;)Ljava/lang/ClassLoader;",
+ ACC_FINAL|ACC_PRIVATE, rewrite_arglist_getclass},
+ {"java.lang.Class", "forName", "(Ljava/lang/String;)Ljava/lang/Class;",
+ "(Ljava/lang/String;Ljava/lang/Class;)Ljava/lang/Class;",
+ ACC_FINAL|ACC_PRIVATE|ACC_STATIC, rewrite_arglist_getclass},
+ {NULL, NULL, NULL, NULL, 0, NULL}};
+
+/* Scan the rules list for replacements for *METHOD_P and replace the
+ args accordingly. If the rewrite results in an access to a private
+ method, update SPECIAL.*/
+
+void
+maybe_rewrite_invocation (tree *method_p, tree *arg_list_p,
+ tree *method_signature_p, tree *special)
+{
+ tree context = DECL_NAME (TYPE_NAME (DECL_CONTEXT (*method_p)));
+ rewrite_rule *p;
+ *special = NULL_TREE;
+
+ for (p = rules; p->classname; p++)
+ {
+ if (get_identifier (p->classname) == context)
+ {
+ tree method = DECL_NAME (*method_p);
+ if (get_identifier (p->method) == method
+ && get_identifier (p->signature) == *method_signature_p)
+ {
+ tree maybe_method
+ = lookup_java_method (DECL_CONTEXT (*method_p),
+ method,
+ get_identifier (p->new_signature));
+ if (! maybe_method && ! flag_verify_invocations)
+ {
+ maybe_method
+ = add_method (DECL_CONTEXT (*method_p), p->flags,
+ method, get_identifier (p->new_signature));
+ DECL_EXTERNAL (maybe_method) = 1;
+ }
+ *method_p = maybe_method;
+ gcc_assert (*method_p);
+ *arg_list_p = p->rewrite_arglist (*arg_list_p);
+ *method_signature_p = get_identifier (p->new_signature);
+ *special = integer_one_node;
+
+ break;
+ }
+ }
+ }
+}
+
+\f
+
tree
build_known_method_ref (tree method, tree method_type ATTRIBUTE_UNUSED,
tree self_type, tree method_signature ATTRIBUTE_UNUSED,
- tree arg_list ATTRIBUTE_UNUSED)
+ tree arg_list ATTRIBUTE_UNUSED, tree special)
{
tree func;
if (is_compiled_class (self_type))
else
{
tree table_index
- = build_int_cst (NULL_TREE, get_symbol_table_index
- (method, &TYPE_ATABLE_METHODS (output_class)));
+ = build_int_cst (NULL_TREE,
+ (get_symbol_table_index
+ (method, special,
+ &TYPE_ATABLE_METHODS (output_class))));
func
= build4 (ARRAY_REF,
TREE_TYPE (TREE_TYPE (TYPE_ATABLE_DECL (output_class))),
reused. */
int
-get_symbol_table_index (tree t, tree *symbol_table)
+get_symbol_table_index (tree t, tree special, tree *symbol_table)
{
int i = 1;
tree method_list;
if (*symbol_table == NULL_TREE)
{
- *symbol_table = build_tree_list (t, t);
+ *symbol_table = build_tree_list (special, t);
return 1;
}
while (1)
{
tree value = TREE_VALUE (method_list);
- if (value == t)
+ tree purpose = TREE_PURPOSE (method_list);
+ if (value == t && purpose == special)
return i;
i++;
if (TREE_CHAIN (method_list) == NULL_TREE)
method_list = TREE_CHAIN (method_list);
}
- TREE_CHAIN (method_list) = build_tree_list (t, t);
+ TREE_CHAIN (method_list) = build_tree_list (special, t);
return i;
}
tree
-build_invokevirtual (tree dtable, tree method)
+build_invokevirtual (tree dtable, tree method, tree special)
{
tree func;
tree nativecode_ptr_ptr_type_node
otable_index
= build_int_cst (NULL_TREE, get_symbol_table_index
- (method, &TYPE_OTABLE_METHODS (output_class)));
+ (method, special,
+ &TYPE_OTABLE_METHODS (output_class)));
method_index = build4 (ARRAY_REF, integer_type_node,
TYPE_OTABLE_DECL (output_class),
otable_index, NULL_TREE, NULL_TREE);
{
int itable_index
= 2 * (get_symbol_table_index
- (method, &TYPE_ITABLE_METHODS (output_class)));
+ (method, NULL_TREE, &TYPE_ITABLE_METHODS (output_class)));
interface
= build4 (ARRAY_REF,
TREE_TYPE (TREE_TYPE (TYPE_ITABLE_DECL (output_class))),
tree call, func, method, arg_list, method_type;
tree check = NULL_TREE;
+ tree special = NULL_TREE;
+
if (! CLASS_LOADED_P (self_type))
{
load_class (self_type, 1);
arg_list = pop_arguments (TYPE_ARG_TYPES (method_type));
flush_quick_stack ();
+ maybe_rewrite_invocation (&method, &arg_list, &method_signature,
+ &special);
+
func = NULL_TREE;
if (opcode == OPCODE_invokestatic)
func = build_known_method_ref (method, method_type, self_type,
- method_signature, arg_list);
+ method_signature, arg_list, special);
else if (opcode == OPCODE_invokespecial
|| (opcode == OPCODE_invokevirtual
&& (METHOD_PRIVATE (method)
TREE_VALUE (arg_list) = save_arg;
check = java_check_reference (save_arg, ! DECL_INIT_P (method));
func = build_known_method_ref (method, method_type, self_type,
- method_signature, arg_list);
+ method_signature, arg_list, special);
}
else
{
tree dtable = invoke_build_dtable (opcode == OPCODE_invokeinterface,
arg_list);
if (opcode == OPCODE_invokevirtual)
- func = build_invokevirtual (dtable, method);
+ func = build_invokevirtual (dtable, method, special);
else
func = build_invokeinterface (dtable, method);
}
return bind;
}
+
+/* Given lvalue EXP, return a volatile expression that references the
+ same object. */
+
+tree
+java_modify_addr_for_volatile (tree exp)
+{
+ tree exp_type = TREE_TYPE (exp);
+ tree v_type
+ = build_qualified_type (exp_type,
+ TYPE_QUALS (exp_type) | TYPE_QUAL_VOLATILE);
+ tree addr = build_fold_addr_expr (exp);
+ v_type = build_pointer_type (v_type);
+ addr = fold_convert (v_type, addr);
+ exp = build_fold_indirect_ref (addr);
+ return exp;
+}
+
+
/* Expand an operation to extract from or store into a field.
IS_STATIC is 1 iff the field is static.
IS_PUTTING is 1 for putting into a field; 0 for getting from the field.
int is_error = 0;
tree original_self_type = self_type;
tree field_decl;
+ tree modify_expr;
if (! CLASS_LOADED_P (self_type))
load_class (self_type, 1);
field_type, flags);
DECL_ARTIFICIAL (field_decl) = 1;
DECL_IGNORED_P (field_decl) = 1;
+#if 0
+ /* FIXME: We should be pessimistic about volatility. We
+ don't know one way or another, but this is safe.
+ However, doing this has bad effects on code quality. We
+ need to look at better ways to do this. */
+ TREE_THIS_VOLATILE (field_decl) = 1;
+#endif
}
else
{
if (DECL_CONTEXT (field_decl) != current_class)
error ("assignment to final field %q+D not in field's class",
field_decl);
- else if (FIELD_STATIC (field_decl))
- {
- if (!DECL_CLINIT_P (current_function_decl))
- warning (0, "assignment to final static field %q+D not in "
- "class initializer",
- field_decl);
- }
- else
- {
- tree cfndecl_name = DECL_NAME (current_function_decl);
- if (! DECL_CONSTRUCTOR_P (current_function_decl)
- && !ID_FINIT_P (cfndecl_name))
- warning (0, "assignment to final field %q+D not in constructor",
- field_decl);
- }
- }
- java_add_stmt (build2 (MODIFY_EXPR, TREE_TYPE (field_ref),
- field_ref, new_value));
+ /* We used to check for assignments to final fields not
+ occurring in the class initializer or in a constructor
+ here. However, this constraint doesn't seem to be
+ enforced by the JVM. */
+ }
+
+ if (TREE_THIS_VOLATILE (field_decl))
+ field_ref = java_modify_addr_for_volatile (field_ref);
+
+ modify_expr = build2 (MODIFY_EXPR, TREE_TYPE (field_ref),
+ field_ref, new_value);
+
+ if (TREE_THIS_VOLATILE (field_decl))
+ java_add_stmt
+ (build3
+ (CALL_EXPR, void_type_node,
+ build_address_of (built_in_decls[BUILT_IN_SYNCHRONIZE]),
+ NULL_TREE, NULL_TREE));
+
+ java_add_stmt (modify_expr);
}
else
- push_value (field_ref);
+ {
+ tree temp = build_decl (VAR_DECL, NULL_TREE, TREE_TYPE (field_ref));
+ java_add_local_var (temp);
+
+ if (TREE_THIS_VOLATILE (field_decl))
+ field_ref = java_modify_addr_for_volatile (field_ref);
+
+ modify_expr
+ = build2 (MODIFY_EXPR, TREE_TYPE (field_ref), temp, field_ref);
+ java_add_stmt (modify_expr);
+
+ if (TREE_THIS_VOLATILE (field_decl))
+ java_add_stmt
+ (build3
+ (CALL_EXPR, void_type_node,
+ build_address_of (built_in_decls[BUILT_IN_SYNCHRONIZE]),
+ NULL_TREE, NULL_TREE));
+
+ push_value (temp);
+ }
+ TREE_THIS_VOLATILE (field_ref) = TREE_THIS_VOLATILE (field_decl);
}
void
c = build_ref_from_constant_pool (index);
c = convert (promote_type (string_type_node), c);
}
+ else if (JPOOL_TAG (jcf, index) == CONSTANT_Class
+ || JPOOL_TAG (jcf, index) == CONSTANT_ResolvedClass)
+ {
+ tree record = get_class_constant (jcf, index);
+ c = build_class_ref (record);
+ }
else
c = get_constant (jcf, index);
push_value (c);
decl = find_local_variable (index, type, oldpc); \
set_local_type (index, type); \
java_add_stmt (build2 (MODIFY_EXPR, type, decl, value)); \
- update_aliases (decl, index, PC); \
}
#define STORE(OPERAND_TYPE, OPERAND_VALUE) \
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