+struct eh_region_d;
+struct pointer_map_t;
+
+/* The type of an exception region. */
+enum eh_region_type
+{
+ /* CLEANUP regions implement e.g. destructors run when exiting a block.
+ They can be generated from both GIMPLE_TRY_FINALLY and GIMPLE_TRY_CATCH
+ nodes. It is expected by the runtime that cleanup regions will *not*
+ resume normal program flow, but will continue propagation of the
+ exception. */
+ ERT_CLEANUP,
+
+ /* TRY regions implement catching an exception. The list of types associated
+ with the attached catch handlers is examined in order by the runtime and
+ control is transfered to the appropriate handler. Note that a NULL type
+ list is a catch-all handler, and that it will catch *all* exceptions
+ including those originating from a different language. */
+ ERT_TRY,
+
+ /* ALLOWED_EXCEPTIONS regions implement exception filtering, e.g. the
+ throw(type-list) specification that can be added to C++ functions.
+ The runtime examines the thrown exception vs the type list, and if
+ the exception does not match, transfers control to the handler. The
+ normal handler for C++ calls __cxa_call_unexpected. */
+ ERT_ALLOWED_EXCEPTIONS,
+
+ /* MUST_NOT_THROW regions prevent all exceptions from propagating. This
+ region type is used in C++ to surround destructors being run inside a
+ CLEANUP region. This differs from an ALLOWED_EXCEPTIONS region with
+ an empty type list in that the runtime is prepared to terminate the
+ program directly. We only generate code for MUST_NOT_THROW regions
+ along control paths that are already handling an exception within the
+ current function. */
+ ERT_MUST_NOT_THROW
+};
+
+
+/* A landing pad for a given exception region. Any transfer of control
+ from the EH runtime to the function happens at a landing pad. */
+
+struct GTY(()) eh_landing_pad_d
+{
+ /* The linked list of all landing pads associated with the region. */
+ struct eh_landing_pad_d *next_lp;
+
+ /* The region with which this landing pad is associated. */
+ struct eh_region_d *region;
+
+ /* At the gimple level, the location to which control will be transfered
+ for this landing pad. There can be both EH and normal edges into the
+ block containing the post-landing-pad label. */
+ tree post_landing_pad;
+
+ /* At the rtl level, the location to which the runtime will transfer
+ control. This differs from the post-landing-pad in that the target's
+ EXCEPTION_RECEIVER pattern will be expanded here, as well as other
+ bookkeeping specific to exceptions. There must not be normal edges
+ into the block containing the landing-pad label. */
+ rtx landing_pad;
+
+ /* The index of this landing pad within fun->eh->lp_array. */
+ int index;
+};
+
+/* A catch handler associated with an ERT_TRY region. */
+
+struct GTY(()) eh_catch_d
+{
+ /* The double-linked list of all catch handlers for the region. */
+ struct eh_catch_d *next_catch;
+ struct eh_catch_d *prev_catch;
+
+ /* A TREE_LIST of runtime type objects that this catch handler
+ will catch, or NULL if all exceptions are caught. */
+ tree type_list;
+
+ /* A TREE_LIST of INTEGER_CSTs that correspond to the type_list entries,
+ having been mapped by assign_filter_values. These integers are to be
+ compared against the __builtin_eh_filter value. */
+ tree filter_list;
+
+ /* The code that should be executed if this catch handler matches the
+ thrown exception. This label is only maintained until
+ pass_lower_eh_dispatch, at which point it is cleared. */
+ tree label;
+};
+
+/* Describes one exception region. */
+
+struct GTY(()) eh_region_d
+{
+ /* The immediately surrounding region. */
+ struct eh_region_d *outer;
+
+ /* The list of immediately contained regions. */
+ struct eh_region_d *inner;
+ struct eh_region_d *next_peer;
+
+ /* The index of this region within fun->eh->region_array. */
+ int index;
+
+ /* Each region does exactly one thing. */
+ enum eh_region_type type;
+
+ /* Holds the action to perform based on the preceding type. */
+ union eh_region_u {
+ struct eh_region_u_try {
+ /* The double-linked list of all catch handlers for this region. */
+ struct eh_catch_d *first_catch;
+ struct eh_catch_d *last_catch;
+ } GTY ((tag ("ERT_TRY"))) eh_try;
+
+ struct eh_region_u_allowed {
+ /* A TREE_LIST of runtime type objects allowed to pass. */
+ tree type_list;
+ /* The code that should be executed if the thrown exception does
+ not match the type list. This label is only maintained until
+ pass_lower_eh_dispatch, at which point it is cleared. */
+ tree label;
+ /* The integer that will be passed by the runtime to signal that
+ we should execute the code at LABEL. This integer is assigned
+ by assign_filter_values and is to be compared against the
+ __builtin_eh_filter value. */
+ int filter;
+ } GTY ((tag ("ERT_ALLOWED_EXCEPTIONS"))) allowed;
+
+ struct eh_region_u_must_not_throw {
+ /* A function decl to be invoked if this region is actually reachable
+ from within the function, rather than implementable from the runtime.
+ The normal way for this to happen is for there to be a CLEANUP region
+ contained within this MUST_NOT_THROW region. Note that if the
+ runtime handles the MUST_NOT_THROW region, we have no control over
+ what termination function is called; it will be decided by the
+ personality function in effect for this CIE. */
+ tree failure_decl;
+ /* The location assigned to the call of FAILURE_DECL, if expanded. */
+ location_t failure_loc;
+ } GTY ((tag ("ERT_MUST_NOT_THROW"))) must_not_throw;
+ } GTY ((desc ("%0.type"))) u;
+
+ /* The list of landing pads associated with this region. */
+ struct eh_landing_pad_d *landing_pads;
+
+ /* EXC_PTR and FILTER values copied from the runtime for this region.
+ Each region gets its own psuedos so that if there are nested exceptions
+ we do not overwrite the values of the first exception. */
+ rtx exc_ptr_reg, filter_reg;
+
+ /* True if this region should use __cxa_end_cleanup instead
+ of _Unwind_Resume. */
+ bool use_cxa_end_cleanup;
+};
+
+typedef struct eh_landing_pad_d *eh_landing_pad;
+typedef struct eh_catch_d *eh_catch;
+typedef struct eh_region_d *eh_region;
+
+DEF_VEC_P(eh_region);
+DEF_VEC_ALLOC_P(eh_region, gc);
+DEF_VEC_ALLOC_P(eh_region, heap);
+
+DEF_VEC_P(eh_landing_pad);
+DEF_VEC_ALLOC_P(eh_landing_pad, gc);
+
+
+/* The exception status for each function. */
+
+struct GTY(()) eh_status
+{
+ /* The tree of all regions for this function. */
+ eh_region region_tree;
+
+ /* The same information as an indexable array. */
+ VEC(eh_region,gc) *region_array;
+
+ /* The landing pads as an indexable array. */
+ VEC(eh_landing_pad,gc) *lp_array;
+
+ /* At the gimple level, a mapping from gimple statement to landing pad
+ or must-not-throw region. See record_stmt_eh_region. */
+ htab_t GTY((param_is (struct throw_stmt_node))) throw_stmt_table;
+
+ /* All of the runtime type data used by the function. These objects
+ are emitted to the lang-specific-data-area for the function. */
+ VEC(tree,gc) *ttype_data;
+
+ /* The table of all action chains. These encode the eh_region tree in
+ a compact form for use by the runtime, and is also emitted to the
+ lang-specific-data-area. Note that the ARM EABI uses a different
+ format for the encoding than all other ports. */
+ union eh_status_u {
+ VEC(tree,gc) * GTY((tag ("1"))) arm_eabi;
+ VEC(uchar,gc) * GTY((tag ("0"))) other;
+ } GTY ((desc ("targetm.arm_eabi_unwinder"))) ehspec_data;
+};
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