From 1ef1bf063b0a944563d37d7d079d9f860d149c0b Mon Sep 17 00:00:00 2001 From: Andrew MacLeod Date: Tue, 10 Aug 1999 16:19:16 +0000 Subject: except.h (eh_nesting_info): Add new structure defintion. Tue Aug 10 10:47:42 EDT 1999 Andrew MacLeod * except.h (eh_nesting_info): Add new structure defintion. (init_eh_nesting_info, free_eh_nesting_info): Add function prototypes. (reachable_handlers, update_rethrow_references): Add function prototypes. * rtl.h (struct rtvec_def): Update comments. REG_EH_RETHROW takes a rethrow symbol instead of an integer exception region number. * flow.c (Make_edges): Use new exception nesting routines to determine which handlers are reachable from a CALL or asynchronous insn. Dont add an edge for calls with a REG_EH_REGION of -1 to non-local goto receivers. (delete_eh_regions): Update rethrow labels, and don't delete regions which are the target of a rethrow. * except.c (struct func_eh_entry): Add rethrow_ref field, now we can avoid overloading the SYMBOL_REF_USED flag. (rethrow_symbol_map): Use new rethrow_ref field. (rethrow_used): Use new rethrow_ref field. (expand_rethrow): REG_EH_RETHROW now has a SYMBOL_REF instead of an integer. Fix formatting. (output_exception_table_entry): Use new rethrow_ref field. (can_throw): Check for EH_REGION_NOTE before deciding whether a CALL can throw or not. (scan_region): Call rethrow_used() instead of accessing data structure. (update_rethrow_references): New function to make sure only regions which are still targets of a rethrow are flagged as such. (process_nestinfo): New static function to initialize a handler list for a specific region. (init_eh_nesting_info): New function to allocate and initialize the list of all EH handlers reachable from all regions. (reachable_handlers): New function to retrieve the list of handlers reachable from a specific region and insn. (free_eh_nesting_info): New function to dispose of a list of reachable handlers. From-SVN: r28647 --- gcc/except.h | 45 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 45 insertions(+) (limited to 'gcc/except.h') diff --git a/gcc/except.h b/gcc/except.h index 2e3e794..73bbe4d 100644 --- a/gcc/except.h +++ b/gcc/except.h @@ -266,6 +266,11 @@ rtx rethrow_symbol_map PROTO((rtx, rtx (*)(rtx))); int rethrow_used PROTO((int)); +/* Update the rethrow references to reflect rethrows which have been + optimized away. */ + +void update_rethrow_references PROTO((void)); + /* Return the region number a this is the rethrow label for. */ int eh_region_from_symbol PROTO((rtx)); @@ -278,6 +283,46 @@ struct handler_info *get_first_handler PROTO((int)); int find_all_handler_type_matches PROTO((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 PROTO((void)); + +/* Get a list of handlers reachable from a an exception region/insn. */ + +int reachable_handlers PROTO((int, eh_nesting_info *, rtx, + handler_info ***handlers)); + +/* Free the eh_nesting_info structure. */ + +void free_eh_nesting_info PROTO((eh_nesting_info *)); + extern void init_eh PROTO((void)); /* Initialization for the per-function EH data. */ -- cgit v1.1