/* Exception Handling interface routines.
- Copyright (C) 1996, 1997 Free Software Foundation, Inc.
+ Copyright (C) 1996, 1997, 1998, 1999, 2000 Free Software Foundation, Inc.
Contributed by Mike Stump <mrs@cygnus.com>.
This file is part of GNU CC.
the Free Software Foundation, 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA. */
-
-#ifndef GET_CODE
-#define rtx int *
+#if !defined(NULL_RTX) && !defined(rtx)
+typedef struct rtx_def *_except_rtx;
+#define rtx _except_rtx
#endif
#ifdef TREE_CODE
EXCEPTION_HANDLER_LABEL is the label corresponding to the handler
for this region.
+ LABEL_USED indicates whether a CATCH block has already used this
+ label or not. New ones are needed for additional catch blocks if
+ it has.
+
+ FALSE_LABEL is used when either setjmp/longjmp exceptions are in
+ use, or old style table exceptions. It contains the label for
+ branching to the next runtime type check as handlers are processed.
+
FINALIZATION is the tree codes for the handler, or is NULL_TREE if
one hasn't been generated yet, or is integer_zero_node to mark the
end of a group of try blocks. */
struct eh_entry {
rtx outer_context;
rtx exception_handler_label;
-
tree finalization;
+ int label_used;
+ rtx false_label;
+ rtx rethrow_label;
+ /* If non-zero, this entry is for a handler created when we left an
+ exception-region via goto. */
+ unsigned goto_entry_p : 1;
};
+#else
+struct label_node;
+struct eh_entry;
+#endif
/* A list of EH_ENTRYs. ENTRY is the entry; CHAIN points to the next
entry in the list, or is NULL if this is the last entry. */
struct eh_queue {
struct eh_node *head;
struct eh_node *tail;
+ struct eh_queue *next;
};
+/* Used to save exception handling status for each function. */
+struct eh_status
+{
+ /* A stack used for keeping track of the currently active exception
+ handling region. As each exception region is started, an entry
+ describing the region is pushed onto this stack. The current
+ region can be found by looking at the top of the stack, and as we
+ exit regions, the corresponding entries are popped.
+
+ Entries cannot overlap; they can be nested. So there is only one
+ entry at most that corresponds to the current instruction, and that
+ is the entry on the top of the stack. */
+ struct eh_stack x_ehstack;
+ /* This stack is used to represent what the current eh region is
+ for the catch blocks beings processed */
+ struct eh_stack x_catchstack;
+ /* A queue used for tracking which exception regions have closed.
+ As we exit a region, we enqueue a new entry. The entries are then
+ dequeued during expand_leftover_cleanups and
+ expand_start_all_catch. */
+ struct eh_queue *x_ehqueue;
+ /* Insns for all of the exception handlers for the current function.
+ They are currently emitted by the frontend code. */
+ rtx x_catch_clauses;
+ /* End of exception handler insn sequence. */
+ rtx x_catch_clauses_last;
+ /* A random data area for the front end's own use. */
+ struct label_node *x_false_label_stack;
+ /* Keeps track of the label to resume to should one want to resume
+ normal control flow out of a handler (instead of, say, returning to
+ the caller of the current function or exiting the program). */
+ struct label_node *x_caught_return_label_stack;
+ /* A stack (TREE_LIST) of lists of handlers. The TREE_VALUE of each
+ node is itself a TREE_CHAINed list of handlers for regions that
+ are not yet closed. The TREE_VALUE of each entry contains the
+ handler for the corresponding entry on the ehstack. */
+ union tree_node *x_protect_list;
+ /* The EH context. Nonzero if the function has already
+ fetched a pointer to the EH context for exception handling. */
+ rtx ehc;
+ /* The label generated by expand_builtin_eh_return. */
+ rtx x_eh_return_stub_label;
+};
+
+#define ehstack (cfun->eh->x_ehstack)
+#define catchstack (cfun->eh->x_catchstack)
+#define ehqueue (cfun->eh->x_ehqueue)
+#define catch_clauses (cfun->eh->x_catch_clauses)
+#define catch_clauses_last (cfun->eh->x_catch_clauses_last)
+#define false_label_stack (cfun->eh->x_false_label_stack)
+#define caught_return_label_stack (cfun->eh->x_caught_return_label_stack)
+#define protect_list (cfun->eh->x_protect_list)
+#define current_function_ehc (cfun->eh->ehc)
+#define eh_return_stub_label (cfun->eh->x_eh_return_stub_label)
+#ifdef TREE_CODE
/* Start an exception handling region. All instructions emitted after
this point are considered to be part of the region until
expand_eh_region_end () is invoked. */
-extern void expand_eh_region_start PROTO((void));
+extern void expand_eh_region_start PARAMS ((void));
/* Just like expand_eh_region_start, except if a cleanup action is
entered on the cleanup chain, the TREE_PURPOSE of the element put
on the chain is DECL. DECL should be the associated VAR_DECL, if
any, otherwise it should be NULL_TREE. */
-extern void expand_eh_region_start_for_decl PROTO((tree));
+extern void expand_eh_region_start_for_decl PARAMS ((tree));
/* Start an exception handling region for the given cleanup action.
All instructions emitted after this point are considered to be part
generation, and optimizes it so as to not need the exception
region. */
-extern int expand_eh_region_start_tree PROTO((tree, tree));
+extern int expand_eh_region_start_tree PARAMS ((tree, tree));
/* End an exception handling region. The information about the region
is found on the top of ehstack.
HANDLER will be transformed to rtl when expand_leftover_cleanups ()
is invoked. */
-extern void expand_eh_region_end PROTO((tree));
+extern void expand_eh_region_end PARAMS ((tree));
/* Push RLABEL or TLABEL onto LABELSTACK. Only one of RLABEL or TLABEL
should be set; the other must be NULL. */
-extern void push_label_entry PROTO((struct label_node **labelstack, rtx rlabel, tree tlabel));
+extern void push_label_entry PARAMS ((struct label_node **labelstack,
+ rtx rlabel, tree tlabel));
/* Pop the topmost entry from LABELSTACK and return its value as an
rtx node. If LABELSTACK is empty, return NULL. */
-extern rtx pop_label_entry PROTO((struct label_node **labelstack));
+extern rtx pop_label_entry PARAMS ((struct label_node **labelstack));
/* Return the topmost entry of LABELSTACK as a tree node, or return
NULL_TREE if LABELSTACK is empty. */
-extern tree top_label_entry PROTO((struct label_node **labelstack));
+extern tree top_label_entry PARAMS ((struct label_node **labelstack));
-/* A set of insns for the catch clauses in the current function. They
- will be emitted at the end of the current function. */
+#endif
-extern rtx catch_clauses;
+/* Test: is exception handling turned on? */
-#endif
+extern int doing_eh PARAMS ((int));
/* Toplevel initialization for EH. */
-extern void init_eh PROTO((void));
+void set_exception_lang_code PARAMS ((int));
+void set_exception_version_code PARAMS ((int));
+
+/* A list of handlers asocciated with an exception region. HANDLER_LABEL
+ is the the label that control should be transfered to if the data
+ in TYPE_INFO matches an exception. a value of NULL_TREE for TYPE_INFO
+ means This is a cleanup, and must always be called. A value of
+ CATCH_ALL_TYPE works like a cleanup, but a call to the runtime matcher
+ is still performed to avoid being caught by a different language
+ exception. NEXT is a pointer to the next handler for this region.
+ NULL means there are no more. */
+
+typedef struct handler_info
+{
+ rtx handler_label;
+ int handler_number;
+ void *type_info;
+ struct handler_info *next;
+} handler_info;
+
+
+/* Add new handler information to an exception range. The first parameter
+ specifies the range number (returned from new_eh_entry()). The second
+ parameter specifies the handler. By default the handler is inserted at
+ the end of the list. A handler list may contain only ONE NULL_TREE
+ typeinfo entry. Regardless where it is positioned, a NULL_TREE entry
+ is always output as the LAST handler in the exception table for a region. */
+
+void add_new_handler PARAMS ((int, struct handler_info *));
+
+/* Remove a handler label. The handler label is being deleted, so all
+ regions which reference this handler should have it removed from their
+ list of possible handlers. Any region which has the final handler
+ removed can be deleted. */
+
+void remove_handler PARAMS ((rtx));
+
+/* Create a new handler structure initialized with the handler label and
+ typeinfo fields passed in. */
+
+struct handler_info *get_new_handler PARAMS ((rtx, void *));
+
+/* Make a duplicate of an exception region by copying all the handlers
+ for an exception region. Return the new handler index. */
+
+int duplicate_eh_handlers PARAMS ((int, int, rtx (*)(rtx)));
+
+/* map symbol refs for rethrow */
+
+rtx rethrow_symbol_map PARAMS ((rtx, rtx (*)(rtx)));
+
+/* Is the rethrow label for a region used? */
+
+int rethrow_used PARAMS ((int));
+
+/* Update the rethrow references to reflect rethrows which have been
+ optimized away. */
+
+void update_rethrow_references PARAMS ((void));
+
+/* Get a pointer to the first handler in an exception region's list. */
+
+struct handler_info *get_first_handler PARAMS ((int));
+
+/* Find all the runtime handlers type matches currently referenced */
+
+int find_all_handler_type_matches PARAMS ((void ***));
+
+/* The eh_nesting_info structure is used to find a list of valid handlers
+ for any arbitrary exception region. When init_eh_nesting_info is called,
+ the information is all pre-calculated and entered in this structure.
+ REGION_INDEX is a vector over all possible region numbers. Since the
+ number of regions is typically much smaller than the range of block
+ numbers, this is a sparse vector and the other data structures are
+ represented as dense vectors. Indexed with an exception region number, this
+ returns the index to use in the other data structures to retreive the
+ correct information.
+ HANDLERS is an array of vectors which point to handler_info structures.
+ when indexed, it gives the list of all possible handlers which can
+ be reached by a throw from this exception region.
+ NUM_HANDLERS is the equivilent array indicating how many handler
+ pointers there are in the HANDLERS vector.
+ OUTER_INDEX indicates which index represents the information for the
+ outer block. 0 indicates there is no outer context.
+ REGION_COUNT is the number of regions. */
+
+typedef struct eh_nesting
+{
+ int *region_index;
+ handler_info ***handlers;
+ int *num_handlers;
+ int *outer_index;
+ int region_count;
+} eh_nesting_info;
+
+/* Initialize the eh_nesting_info structure. */
+
+eh_nesting_info *init_eh_nesting_info PARAMS ((void));
+
+/* Get a list of handlers reachable from a an exception region/insn. */
+
+int reachable_handlers PARAMS ((int, eh_nesting_info *, rtx,
+ handler_info ***handlers));
+
+/* Free the eh_nesting_info structure. */
+
+void free_eh_nesting_info PARAMS ((eh_nesting_info *));
+
+extern void init_eh PARAMS ((void));
/* Initialization for the per-function EH data. */
-extern void init_eh_for_function PROTO((void));
+extern void init_eh_for_function PARAMS ((void));
+
+/* Generate an exception label. Use instead of gen_label_rtx */
+
+extern rtx gen_exception_label PARAMS ((void));
/* Adds an EH table entry for EH entry number N. Called from
final_scan_insn for NOTE_INSN_EH_REGION_BEG. */
-extern void add_eh_table_entry PROTO((int n));
+extern void add_eh_table_entry PARAMS ((int n));
+
+/* Start a catch clause, triggered by runtime value paramter. */
+
+#ifdef TREE_CODE
+extern void start_catch_handler PARAMS ((tree));
+#endif
+
+/* End an individual catch clause. */
+
+extern void end_catch_handler PARAMS ((void));
/* Returns a non-zero value if we need to output an exception table. */
-extern int exception_table_p PROTO((void));
+extern int exception_table_p PARAMS ((void));
/* Outputs the exception table if we have one. */
-extern void output_exception_table PROTO((void));
+extern void output_exception_table PARAMS ((void));
+extern void output_exception_table_data PARAMS ((void));
+
+/* Free the exception table. */
+
+extern void free_exception_table PARAMS((void));
+
+/* Used by the ia64 unwind format to output data for an individual
+ function. */
+
+extern void output_function_exception_table PARAMS((void));
/* Given a return address in ADDR, determine the address we should use
to find the corresponding EH region. */
-extern rtx eh_outer_context PROTO((rtx addr));
+extern rtx eh_outer_context PARAMS ((rtx addr));
/* Called at the start of a block of try statements for which there is
a supplied catch handler. */
-extern void expand_start_try_stmts PROTO((void));
+extern void expand_start_try_stmts PARAMS ((void));
/* Called at the start of a block of catch statements. It terminates the
previous set of try statements. */
-extern void expand_start_all_catch PROTO((void));
+extern void expand_start_all_catch PARAMS ((void));
/* Called at the end of a block of catch statements. */
-extern void expand_end_all_catch PROTO((void));
+extern void expand_end_all_catch PARAMS ((void));
+
+/* Begin a region that will contain entries created with
+ add_partial_entry. */
+
+extern void begin_protect_partials PARAMS ((void));
#ifdef TREE_CODE
/* Create a new exception region and add the handler for the region
onto a list. These regions will be ended (and their handlers
emitted) when end_protect_partials is invoked. */
-extern void add_partial_entry PROTO((tree handler));
+extern void add_partial_entry PARAMS ((tree handler));
#endif
/* End all of the pending exception regions that have handlers added with
push_protect_entry (). */
-extern void end_protect_partials PROTO((void));
+extern void end_protect_partials PARAMS ((void));
-/* An internal throw with a direct CONTEXT we want to throw
- from. CONTEXT must be a label. */
+/* An internal throw. */
-extern void expand_internal_throw PROTO((rtx context));
+extern void expand_internal_throw PARAMS ((void));
/* Called from expand_exception_blocks and expand_end_catch_block to
expand and pending handlers. */
-extern void expand_leftover_cleanups PROTO((void));
-
-/* If necessary, emit insns for the start of per-function unwinder for
- the current function. */
+extern void expand_leftover_cleanups PARAMS ((void));
-extern void emit_unwinder PROTO((void));
+/* If necessary, emit insns to get EH context for the current
+ function. */
-/* If necessary, emit insns for the end of the per-function unwinder
- for the current function. */
-
-extern void end_eh_unwinder PROTO((void));
+extern void emit_eh_context PARAMS ((void));
/* Builds a list of handler labels and puts them in the global
variable exception_handler_labels. */
-extern void find_exception_handler_labels PROTO((void));
+extern void find_exception_handler_labels PARAMS ((void));
-/* Performs sanity checking on the check_exception_handler_labels
- list. */
+/* Determine if an arbitrary label is an exception label */
-extern void check_exception_handler_labels PROTO((void));
+extern int is_exception_handler_label PARAMS ((int));
-/* A stack used to keep track of the label used to resume normal program
- flow out of the current exception handler region. */
+/* Performs sanity checking on the check_exception_handler_labels
+ list. */
-extern struct label_node *caught_return_label_stack;
+extern void check_exception_handler_labels PARAMS ((void));
/* Keeps track of the label used as the context of a throw to rethrow an
exception to the outer exception region. */
extern struct label_node *outer_context_label_stack;
-/* A random area used for purposes elsewhere. */
-
-extern struct label_node *false_label_stack;
-
/* A list of labels used for exception handlers. It is created by
find_exception_handler_labels for the optimization passes. */
extern rtx exception_handler_labels;
-/* The rtx for the saved PC value. */
+/* Determine if the given INSN can throw an exception. */
-extern rtx eh_saved_pc_rtx;
+extern int can_throw PARAMS ((rtx));
+
+/* Return nonzero if nothing in this function can throw. */
+
+extern int nothrow_function_p PARAMS ((void));
/* Performs optimizations for exception handling, such as removing
unnecessary exception regions. Invoked from jump_optimize (). */
-extern void exception_optimize PROTO((void));
+extern void exception_optimize PARAMS ((void));
+
+/* Return EH context (and set it up once per fn). */
+extern rtx get_eh_context PARAMS ((void));
/* Get the dynamic handler chain. */
-extern rtx get_dynamic_handler_chain PROTO((void));
+extern rtx get_dynamic_handler_chain PARAMS ((void));
/* Get the dynamic cleanup chain. */
-extern rtx get_dynamic_cleanup_chain PROTO((void));
+extern rtx get_dynamic_cleanup_chain PARAMS ((void));
/* Throw an exception. */
-extern void emit_throw PROTO((void));
+extern void emit_throw PARAMS ((void));
+
+/* Save away the current ehqueue. */
+extern void push_ehqueue PARAMS ((void));
+
+/* Restore a previously pushed ehqueue. */
+extern void pop_ehqueue PARAMS ((void));
/* One to use setjmp/longjmp method of generating code. */
extern int protect_cleanup_actions_with_terminate;
#ifdef TREE_CODE
-extern tree protect_with_terminate PROTO((tree));
+extern tree protect_with_terminate PARAMS ((tree));
+#endif
+
+extern void expand_fixup_region_start PARAMS ((void));
+#ifdef TREE_CODE
+extern void expand_fixup_region_end PARAMS ((tree));
#endif
/* Various hooks for the DWARF 2 __throw routine. */
-void expand_builtin_unwind_init PROTO((void));
-rtx expand_builtin_dwarf_fp_regnum PROTO((void));
-rtx expand_builtin_eh_stub PROTO((void));
+void expand_builtin_unwind_init PARAMS ((void));
+rtx expand_builtin_dwarf_fp_regnum PARAMS ((void));
#ifdef TREE_CODE
-rtx expand_builtin_frob_return_addr PROTO((tree));
-rtx expand_builtin_extract_return_addr PROTO((tree));
-void expand_builtin_set_return_addr_reg PROTO((tree));
-void expand_builtin_set_eh_regs PROTO((tree, tree));
-rtx expand_builtin_dwarf_reg_size PROTO((tree, rtx));
+rtx expand_builtin_frob_return_addr PARAMS ((tree));
+rtx expand_builtin_extract_return_addr PARAMS ((tree));
+void expand_builtin_init_dwarf_reg_sizes PARAMS ((tree));
+void expand_builtin_eh_return PARAMS ((tree, tree, tree));
+#endif
+void expand_eh_return PARAMS ((void));
+
+
+/* Checking whether 2 instructions are within the same exception region. */
+
+int in_same_eh_region PARAMS ((rtx, rtx));
+void free_insn_eh_region PARAMS ((void));
+void init_insn_eh_region PARAMS ((rtx, int));
+
+#ifdef rtx
+#undef rtx
#endif