| /* Implements exception handling. |
| Copyright (C) 1989-2022 Free Software Foundation, Inc. |
| Contributed by Mike Stump <mrs@cygnus.com>. |
| |
| This file is part of GCC. |
| |
| GCC is free software; you can redistribute it and/or modify it under |
| the terms of the GNU General Public License as published by the Free |
| Software Foundation; either version 3, or (at your option) any later |
| version. |
| |
| GCC is distributed in the hope that it will be useful, but WITHOUT ANY |
| WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| for more details. |
| |
| You should have received a copy of the GNU General Public License |
| along with GCC; see the file COPYING3. If not see |
| <http://www.gnu.org/licenses/>. */ |
| |
| |
| /* An exception is an event that can be "thrown" from within a |
| function. This event can then be "caught" by the callers of |
| the function. |
| |
| The representation of exceptions changes several times during |
| the compilation process: |
| |
| In the beginning, in the front end, we have the GENERIC trees |
| TRY_CATCH_EXPR, TRY_FINALLY_EXPR, EH_ELSE_EXPR, WITH_CLEANUP_EXPR, |
| CLEANUP_POINT_EXPR, CATCH_EXPR, and EH_FILTER_EXPR. |
| |
| During initial gimplification (gimplify.cc) these are lowered to the |
| GIMPLE_TRY, GIMPLE_CATCH, GIMPLE_EH_ELSE, and GIMPLE_EH_FILTER |
| nodes. The WITH_CLEANUP_EXPR and CLEANUP_POINT_EXPR nodes are |
| converted into GIMPLE_TRY_FINALLY nodes; the others are a more |
| direct 1-1 conversion. |
| |
| During pass_lower_eh (tree-eh.cc) we record the nested structure |
| of the TRY nodes in EH_REGION nodes in CFUN->EH->REGION_TREE. |
| We expand the eh_protect_cleanup_actions langhook into MUST_NOT_THROW |
| regions at this time. We can then flatten the statements within |
| the TRY nodes to straight-line code. Statements that had been within |
| TRY nodes that can throw are recorded within CFUN->EH->THROW_STMT_TABLE, |
| so that we may remember what action is supposed to be taken if |
| a given statement does throw. During this lowering process, |
| we create an EH_LANDING_PAD node for each EH_REGION that has |
| some code within the function that needs to be executed if a |
| throw does happen. We also create RESX statements that are |
| used to transfer control from an inner EH_REGION to an outer |
| EH_REGION. We also create EH_DISPATCH statements as placeholders |
| for a runtime type comparison that should be made in order to |
| select the action to perform among different CATCH and EH_FILTER |
| regions. |
| |
| During pass_lower_eh_dispatch (tree-eh.cc), which is run after |
| all inlining is complete, we are able to run assign_filter_values, |
| which allows us to map the set of types manipulated by all of the |
| CATCH and EH_FILTER regions to a set of integers. This set of integers |
| will be how the exception runtime communicates with the code generated |
| within the function. We then expand the GIMPLE_EH_DISPATCH statements |
| to a switch or conditional branches that use the argument provided by |
| the runtime (__builtin_eh_filter) and the set of integers we computed |
| in assign_filter_values. |
| |
| During pass_lower_resx (tree-eh.cc), which is run near the end |
| of optimization, we expand RESX statements. If the eh region |
| that is outer to the RESX statement is a MUST_NOT_THROW, then |
| the RESX expands to some form of abort statement. If the eh |
| region that is outer to the RESX statement is within the current |
| function, then the RESX expands to a bookkeeping call |
| (__builtin_eh_copy_values) and a goto. Otherwise, the next |
| handler for the exception must be within a function somewhere |
| up the call chain, so we call back into the exception runtime |
| (__builtin_unwind_resume). |
| |
| During pass_expand (cfgexpand.cc), we generate REG_EH_REGION notes |
| that create an rtl to eh_region mapping that corresponds to the |
| gimple to eh_region mapping that had been recorded in the |
| THROW_STMT_TABLE. |
| |
| Then, via finish_eh_generation, we generate the real landing pads |
| to which the runtime will actually transfer control. These new |
| landing pads perform whatever bookkeeping is needed by the target |
| backend in order to resume execution within the current function. |
| Each of these new landing pads falls through into the post_landing_pad |
| label which had been used within the CFG up to this point. All |
| exception edges within the CFG are redirected to the new landing pads. |
| If the target uses setjmp to implement exceptions, the various extra |
| calls into the runtime to register and unregister the current stack |
| frame are emitted at this time. |
| |
| During pass_convert_to_eh_region_ranges (except.cc), we transform |
| the REG_EH_REGION notes attached to individual insns into |
| non-overlapping ranges of insns bounded by NOTE_INSN_EH_REGION_BEG |
| and NOTE_INSN_EH_REGION_END. Each insn within such ranges has the |
| same associated action within the exception region tree, meaning |
| that (1) the exception is caught by the same landing pad within the |
| current function, (2) the exception is blocked by the runtime with |
| a MUST_NOT_THROW region, or (3) the exception is not handled at all |
| within the current function. |
| |
| Finally, during assembly generation, we call |
| output_function_exception_table (except.cc) to emit the tables with |
| which the exception runtime can determine if a given stack frame |
| handles a given exception, and if so what filter value to provide |
| to the function when the non-local control transfer is effected. |
| If the target uses dwarf2 unwinding to implement exceptions, then |
| output_call_frame_info (dwarf2out.cc) emits the required unwind data. */ |
| |
| |
| #include "config.h" |
| #include "system.h" |
| #include "coretypes.h" |
| #include "backend.h" |
| #include "target.h" |
| #include "rtl.h" |
| #include "tree.h" |
| #include "cfghooks.h" |
| #include "tree-pass.h" |
| #include "memmodel.h" |
| #include "tm_p.h" |
| #include "stringpool.h" |
| #include "expmed.h" |
| #include "optabs.h" |
| #include "emit-rtl.h" |
| #include "cgraph.h" |
| #include "diagnostic.h" |
| #include "fold-const.h" |
| #include "stor-layout.h" |
| #include "explow.h" |
| #include "stmt.h" |
| #include "expr.h" |
| #include "calls.h" |
| #include "libfuncs.h" |
| #include "except.h" |
| #include "output.h" |
| #include "dwarf2asm.h" |
| #include "dwarf2.h" |
| #include "common/common-target.h" |
| #include "langhooks.h" |
| #include "cfgrtl.h" |
| #include "tree-pretty-print.h" |
| #include "cfgloop.h" |
| #include "builtins.h" |
| #include "tree-hash-traits.h" |
| #include "flags.h" |
| |
| static GTY(()) int call_site_base; |
| |
| static GTY(()) hash_map<tree_hash, tree> *type_to_runtime_map; |
| |
| static GTY(()) tree setjmp_fn; |
| |
| /* Describe the SjLj_Function_Context structure. */ |
| static GTY(()) tree sjlj_fc_type_node; |
| static int sjlj_fc_call_site_ofs; |
| static int sjlj_fc_data_ofs; |
| static int sjlj_fc_personality_ofs; |
| static int sjlj_fc_lsda_ofs; |
| static int sjlj_fc_jbuf_ofs; |
| |
| |
| struct GTY(()) call_site_record_d |
| { |
| rtx landing_pad; |
| int action; |
| }; |
| |
| /* In the following structure and associated functions, |
| we represent entries in the action table as 1-based indices. |
| Special cases are: |
| |
| 0: null action record, non-null landing pad; implies cleanups |
| -1: null action record, null landing pad; implies no action |
| -2: no call-site entry; implies must_not_throw |
| -3: we have yet to process outer regions |
| |
| Further, no special cases apply to the "next" field of the record. |
| For next, 0 means end of list. */ |
| |
| struct action_record |
| { |
| int offset; |
| int filter; |
| int next; |
| }; |
| |
| /* Hashtable helpers. */ |
| |
| struct action_record_hasher : free_ptr_hash <action_record> |
| { |
| static inline hashval_t hash (const action_record *); |
| static inline bool equal (const action_record *, const action_record *); |
| }; |
| |
| inline hashval_t |
| action_record_hasher::hash (const action_record *entry) |
| { |
| return entry->next * 1009 + entry->filter; |
| } |
| |
| inline bool |
| action_record_hasher::equal (const action_record *entry, |
| const action_record *data) |
| { |
| return entry->filter == data->filter && entry->next == data->next; |
| } |
| |
| typedef hash_table<action_record_hasher> action_hash_type; |
| |
| static bool get_eh_region_and_lp_from_rtx (const_rtx, eh_region *, |
| eh_landing_pad *); |
| |
| static void dw2_build_landing_pads (void); |
| |
| static int collect_one_action_chain (action_hash_type *, eh_region); |
| static int add_call_site (rtx, int, int); |
| |
| static void push_uleb128 (vec<uchar, va_gc> **, unsigned int); |
| static void push_sleb128 (vec<uchar, va_gc> **, int); |
| static int dw2_size_of_call_site_table (int); |
| static int sjlj_size_of_call_site_table (void); |
| static void dw2_output_call_site_table (int, int); |
| static void sjlj_output_call_site_table (void); |
| |
| |
| void |
| init_eh (void) |
| { |
| if (! flag_exceptions) |
| return; |
| |
| type_to_runtime_map = hash_map<tree_hash, tree>::create_ggc (31); |
| |
| /* Create the SjLj_Function_Context structure. This should match |
| the definition in unwind-sjlj.c. */ |
| if (targetm_common.except_unwind_info (&global_options) == UI_SJLJ) |
| { |
| tree f_jbuf, f_per, f_lsda, f_prev, f_cs, f_data, tmp; |
| |
| sjlj_fc_type_node = lang_hooks.types.make_type (RECORD_TYPE); |
| |
| f_prev = build_decl (BUILTINS_LOCATION, |
| FIELD_DECL, get_identifier ("__prev"), |
| build_pointer_type (sjlj_fc_type_node)); |
| DECL_FIELD_CONTEXT (f_prev) = sjlj_fc_type_node; |
| |
| f_cs = build_decl (BUILTINS_LOCATION, |
| FIELD_DECL, get_identifier ("__call_site"), |
| integer_type_node); |
| DECL_FIELD_CONTEXT (f_cs) = sjlj_fc_type_node; |
| |
| tmp = build_index_type (size_int (4 - 1)); |
| tmp = build_array_type (lang_hooks.types.type_for_mode |
| (targetm.unwind_word_mode (), 1), |
| tmp); |
| f_data = build_decl (BUILTINS_LOCATION, |
| FIELD_DECL, get_identifier ("__data"), tmp); |
| DECL_FIELD_CONTEXT (f_data) = sjlj_fc_type_node; |
| |
| f_per = build_decl (BUILTINS_LOCATION, |
| FIELD_DECL, get_identifier ("__personality"), |
| ptr_type_node); |
| DECL_FIELD_CONTEXT (f_per) = sjlj_fc_type_node; |
| |
| f_lsda = build_decl (BUILTINS_LOCATION, |
| FIELD_DECL, get_identifier ("__lsda"), |
| ptr_type_node); |
| DECL_FIELD_CONTEXT (f_lsda) = sjlj_fc_type_node; |
| |
| #ifdef DONT_USE_BUILTIN_SETJMP |
| #ifdef JMP_BUF_SIZE |
| tmp = size_int (JMP_BUF_SIZE - 1); |
| #else |
| /* Should be large enough for most systems, if it is not, |
| JMP_BUF_SIZE should be defined with the proper value. It will |
| also tend to be larger than necessary for most systems, a more |
| optimal port will define JMP_BUF_SIZE. */ |
| tmp = size_int (FIRST_PSEUDO_REGISTER + 2 - 1); |
| #endif |
| #else |
| /* Compute a minimally sized jump buffer. We need room to store at |
| least 3 pointers - stack pointer, frame pointer and return address. |
| Plus for some targets we need room for an extra pointer - in the |
| case of MIPS this is the global pointer. This makes a total of four |
| pointers, but to be safe we actually allocate room for 5. |
| |
| If pointers are smaller than words then we allocate enough room for |
| 5 words, just in case the backend needs this much room. For more |
| discussion on this issue see: |
| http://gcc.gnu.org/ml/gcc-patches/2014-05/msg00313.html. */ |
| if (POINTER_SIZE > BITS_PER_WORD) |
| tmp = size_int (5 - 1); |
| else |
| tmp = size_int ((5 * BITS_PER_WORD / POINTER_SIZE) - 1); |
| #endif |
| |
| tmp = build_index_type (tmp); |
| tmp = build_array_type (ptr_type_node, tmp); |
| f_jbuf = build_decl (BUILTINS_LOCATION, |
| FIELD_DECL, get_identifier ("__jbuf"), tmp); |
| #ifdef DONT_USE_BUILTIN_SETJMP |
| /* We don't know what the alignment requirements of the |
| runtime's jmp_buf has. Overestimate. */ |
| SET_DECL_ALIGN (f_jbuf, BIGGEST_ALIGNMENT); |
| DECL_USER_ALIGN (f_jbuf) = 1; |
| #endif |
| DECL_FIELD_CONTEXT (f_jbuf) = sjlj_fc_type_node; |
| |
| TYPE_FIELDS (sjlj_fc_type_node) = f_prev; |
| TREE_CHAIN (f_prev) = f_cs; |
| TREE_CHAIN (f_cs) = f_data; |
| TREE_CHAIN (f_data) = f_per; |
| TREE_CHAIN (f_per) = f_lsda; |
| TREE_CHAIN (f_lsda) = f_jbuf; |
| |
| layout_type (sjlj_fc_type_node); |
| |
| /* Cache the interesting field offsets so that we have |
| easy access from rtl. */ |
| sjlj_fc_call_site_ofs |
| = (tree_to_uhwi (DECL_FIELD_OFFSET (f_cs)) |
| + tree_to_uhwi (DECL_FIELD_BIT_OFFSET (f_cs)) / BITS_PER_UNIT); |
| sjlj_fc_data_ofs |
| = (tree_to_uhwi (DECL_FIELD_OFFSET (f_data)) |
| + tree_to_uhwi (DECL_FIELD_BIT_OFFSET (f_data)) / BITS_PER_UNIT); |
| sjlj_fc_personality_ofs |
| = (tree_to_uhwi (DECL_FIELD_OFFSET (f_per)) |
| + tree_to_uhwi (DECL_FIELD_BIT_OFFSET (f_per)) / BITS_PER_UNIT); |
| sjlj_fc_lsda_ofs |
| = (tree_to_uhwi (DECL_FIELD_OFFSET (f_lsda)) |
| + tree_to_uhwi (DECL_FIELD_BIT_OFFSET (f_lsda)) / BITS_PER_UNIT); |
| sjlj_fc_jbuf_ofs |
| = (tree_to_uhwi (DECL_FIELD_OFFSET (f_jbuf)) |
| + tree_to_uhwi (DECL_FIELD_BIT_OFFSET (f_jbuf)) / BITS_PER_UNIT); |
| |
| #ifdef DONT_USE_BUILTIN_SETJMP |
| tmp = build_function_type_list (integer_type_node, TREE_TYPE (f_jbuf), |
| NULL); |
| setjmp_fn = build_decl (BUILTINS_LOCATION, FUNCTION_DECL, |
| get_identifier ("setjmp"), tmp); |
| TREE_PUBLIC (setjmp_fn) = 1; |
| DECL_EXTERNAL (setjmp_fn) = 1; |
| DECL_ASSEMBLER_NAME (setjmp_fn); |
| #endif |
| } |
| } |
| |
| void |
| init_eh_for_function (void) |
| { |
| cfun->eh = ggc_cleared_alloc<eh_status> (); |
| |
| /* Make sure zero'th entries are used. */ |
| vec_safe_push (cfun->eh->region_array, (eh_region)0); |
| vec_safe_push (cfun->eh->lp_array, (eh_landing_pad)0); |
| } |
| |
| /* Routines to generate the exception tree somewhat directly. |
| These are used from tree-eh.cc when processing exception related |
| nodes during tree optimization. */ |
| |
| static eh_region |
| gen_eh_region (enum eh_region_type type, eh_region outer) |
| { |
| eh_region new_eh; |
| |
| /* Insert a new blank region as a leaf in the tree. */ |
| new_eh = ggc_cleared_alloc<eh_region_d> (); |
| new_eh->type = type; |
| new_eh->outer = outer; |
| if (outer) |
| { |
| new_eh->next_peer = outer->inner; |
| outer->inner = new_eh; |
| } |
| else |
| { |
| new_eh->next_peer = cfun->eh->region_tree; |
| cfun->eh->region_tree = new_eh; |
| } |
| |
| new_eh->index = vec_safe_length (cfun->eh->region_array); |
| vec_safe_push (cfun->eh->region_array, new_eh); |
| |
| /* Copy the language's notion of whether to use __cxa_end_cleanup. */ |
| if (targetm.arm_eabi_unwinder && lang_hooks.eh_use_cxa_end_cleanup) |
| new_eh->use_cxa_end_cleanup = true; |
| |
| return new_eh; |
| } |
| |
| eh_region |
| gen_eh_region_cleanup (eh_region outer) |
| { |
| return gen_eh_region (ERT_CLEANUP, outer); |
| } |
| |
| eh_region |
| gen_eh_region_try (eh_region outer) |
| { |
| return gen_eh_region (ERT_TRY, outer); |
| } |
| |
| eh_catch |
| gen_eh_region_catch (eh_region t, tree type_or_list) |
| { |
| eh_catch c, l; |
| tree type_list, type_node; |
| |
| gcc_assert (t->type == ERT_TRY); |
| |
| /* Ensure to always end up with a type list to normalize further |
| processing, then register each type against the runtime types map. */ |
| type_list = type_or_list; |
| if (type_or_list) |
| { |
| if (TREE_CODE (type_or_list) != TREE_LIST) |
| type_list = tree_cons (NULL_TREE, type_or_list, NULL_TREE); |
| |
| type_node = type_list; |
| for (; type_node; type_node = TREE_CHAIN (type_node)) |
| add_type_for_runtime (TREE_VALUE (type_node)); |
| } |
| |
| c = ggc_cleared_alloc<eh_catch_d> (); |
| c->type_list = type_list; |
| l = t->u.eh_try.last_catch; |
| c->prev_catch = l; |
| if (l) |
| l->next_catch = c; |
| else |
| t->u.eh_try.first_catch = c; |
| t->u.eh_try.last_catch = c; |
| |
| return c; |
| } |
| |
| eh_region |
| gen_eh_region_allowed (eh_region outer, tree allowed) |
| { |
| eh_region region = gen_eh_region (ERT_ALLOWED_EXCEPTIONS, outer); |
| region->u.allowed.type_list = allowed; |
| |
| for (; allowed ; allowed = TREE_CHAIN (allowed)) |
| add_type_for_runtime (TREE_VALUE (allowed)); |
| |
| return region; |
| } |
| |
| eh_region |
| gen_eh_region_must_not_throw (eh_region outer) |
| { |
| return gen_eh_region (ERT_MUST_NOT_THROW, outer); |
| } |
| |
| eh_landing_pad |
| gen_eh_landing_pad (eh_region region) |
| { |
| eh_landing_pad lp = ggc_cleared_alloc<eh_landing_pad_d> (); |
| |
| lp->next_lp = region->landing_pads; |
| lp->region = region; |
| lp->index = vec_safe_length (cfun->eh->lp_array); |
| region->landing_pads = lp; |
| |
| vec_safe_push (cfun->eh->lp_array, lp); |
| |
| return lp; |
| } |
| |
| eh_region |
| get_eh_region_from_number_fn (struct function *ifun, int i) |
| { |
| return (*ifun->eh->region_array)[i]; |
| } |
| |
| eh_region |
| get_eh_region_from_number (int i) |
| { |
| return get_eh_region_from_number_fn (cfun, i); |
| } |
| |
| eh_landing_pad |
| get_eh_landing_pad_from_number_fn (struct function *ifun, int i) |
| { |
| return (*ifun->eh->lp_array)[i]; |
| } |
| |
| eh_landing_pad |
| get_eh_landing_pad_from_number (int i) |
| { |
| return get_eh_landing_pad_from_number_fn (cfun, i); |
| } |
| |
| eh_region |
| get_eh_region_from_lp_number_fn (struct function *ifun, int i) |
| { |
| if (i < 0) |
| return (*ifun->eh->region_array)[-i]; |
| else if (i == 0) |
| return NULL; |
| else |
| { |
| eh_landing_pad lp; |
| lp = (*ifun->eh->lp_array)[i]; |
| return lp->region; |
| } |
| } |
| |
| eh_region |
| get_eh_region_from_lp_number (int i) |
| { |
| return get_eh_region_from_lp_number_fn (cfun, i); |
| } |
| |
| /* Returns true if the current function has exception handling regions. */ |
| |
| bool |
| current_function_has_exception_handlers (void) |
| { |
| return cfun->eh->region_tree != NULL; |
| } |
| |
| /* A subroutine of duplicate_eh_regions. Copy the eh_region tree at OLD. |
| Root it at OUTER, and apply LP_OFFSET to the lp numbers. */ |
| |
| struct duplicate_eh_regions_data |
| { |
| duplicate_eh_regions_map label_map; |
| void *label_map_data; |
| hash_map<void *, void *> *eh_map; |
| }; |
| |
| static void |
| duplicate_eh_regions_1 (struct duplicate_eh_regions_data *data, |
| eh_region old_r, eh_region outer) |
| { |
| eh_landing_pad old_lp, new_lp; |
| eh_region new_r; |
| |
| new_r = gen_eh_region (old_r->type, outer); |
| gcc_assert (!data->eh_map->put (old_r, new_r)); |
| |
| switch (old_r->type) |
| { |
| case ERT_CLEANUP: |
| break; |
| |
| case ERT_TRY: |
| { |
| eh_catch oc, nc; |
| for (oc = old_r->u.eh_try.first_catch; oc ; oc = oc->next_catch) |
| { |
| /* We should be doing all our region duplication before and |
| during inlining, which is before filter lists are created. */ |
| gcc_assert (oc->filter_list == NULL); |
| nc = gen_eh_region_catch (new_r, oc->type_list); |
| nc->label = data->label_map (oc->label, data->label_map_data); |
| } |
| } |
| break; |
| |
| case ERT_ALLOWED_EXCEPTIONS: |
| new_r->u.allowed.type_list = old_r->u.allowed.type_list; |
| if (old_r->u.allowed.label) |
| new_r->u.allowed.label |
| = data->label_map (old_r->u.allowed.label, data->label_map_data); |
| else |
| new_r->u.allowed.label = NULL_TREE; |
| break; |
| |
| case ERT_MUST_NOT_THROW: |
| new_r->u.must_not_throw.failure_loc = |
| LOCATION_LOCUS (old_r->u.must_not_throw.failure_loc); |
| new_r->u.must_not_throw.failure_decl = |
| old_r->u.must_not_throw.failure_decl; |
| break; |
| } |
| |
| for (old_lp = old_r->landing_pads; old_lp ; old_lp = old_lp->next_lp) |
| { |
| /* Don't bother copying unused landing pads. */ |
| if (old_lp->post_landing_pad == NULL) |
| continue; |
| |
| new_lp = gen_eh_landing_pad (new_r); |
| gcc_assert (!data->eh_map->put (old_lp, new_lp)); |
| |
| new_lp->post_landing_pad |
| = data->label_map (old_lp->post_landing_pad, data->label_map_data); |
| EH_LANDING_PAD_NR (new_lp->post_landing_pad) = new_lp->index; |
| } |
| |
| /* Make sure to preserve the original use of __cxa_end_cleanup. */ |
| new_r->use_cxa_end_cleanup = old_r->use_cxa_end_cleanup; |
| |
| for (old_r = old_r->inner; old_r ; old_r = old_r->next_peer) |
| duplicate_eh_regions_1 (data, old_r, new_r); |
| } |
| |
| /* Duplicate the EH regions from IFUN rooted at COPY_REGION into |
| the current function and root the tree below OUTER_REGION. |
| The special case of COPY_REGION of NULL means all regions. |
| Remap labels using MAP/MAP_DATA callback. Return a pointer map |
| that allows the caller to remap uses of both EH regions and |
| EH landing pads. */ |
| |
| hash_map<void *, void *> * |
| duplicate_eh_regions (struct function *ifun, |
| eh_region copy_region, int outer_lp, |
| duplicate_eh_regions_map map, void *map_data) |
| { |
| struct duplicate_eh_regions_data data; |
| eh_region outer_region; |
| |
| if (flag_checking) |
| verify_eh_tree (ifun); |
| |
| data.label_map = map; |
| data.label_map_data = map_data; |
| data.eh_map = new hash_map<void *, void *>; |
| |
| outer_region = get_eh_region_from_lp_number_fn (cfun, outer_lp); |
| |
| /* Copy all the regions in the subtree. */ |
| if (copy_region) |
| duplicate_eh_regions_1 (&data, copy_region, outer_region); |
| else |
| { |
| eh_region r; |
| for (r = ifun->eh->region_tree; r ; r = r->next_peer) |
| duplicate_eh_regions_1 (&data, r, outer_region); |
| } |
| |
| if (flag_checking) |
| verify_eh_tree (cfun); |
| |
| return data.eh_map; |
| } |
| |
| /* Return the region that is outer to both REGION_A and REGION_B in IFUN. */ |
| |
| eh_region |
| eh_region_outermost (struct function *ifun, eh_region region_a, |
| eh_region region_b) |
| { |
| gcc_assert (ifun->eh->region_array); |
| gcc_assert (ifun->eh->region_tree); |
| |
| auto_sbitmap b_outer (ifun->eh->region_array->length ()); |
| bitmap_clear (b_outer); |
| |
| do |
| { |
| bitmap_set_bit (b_outer, region_b->index); |
| region_b = region_b->outer; |
| } |
| while (region_b); |
| |
| do |
| { |
| if (bitmap_bit_p (b_outer, region_a->index)) |
| break; |
| region_a = region_a->outer; |
| } |
| while (region_a); |
| |
| return region_a; |
| } |
| |
| void |
| add_type_for_runtime (tree type) |
| { |
| /* If TYPE is NOP_EXPR, it means that it already is a runtime type. */ |
| if (TREE_CODE (type) == NOP_EXPR) |
| return; |
| |
| bool existed = false; |
| tree *slot = &type_to_runtime_map->get_or_insert (type, &existed); |
| if (!existed) |
| *slot = lang_hooks.eh_runtime_type (type); |
| } |
| |
| tree |
| lookup_type_for_runtime (tree type) |
| { |
| /* If TYPE is NOP_EXPR, it means that it already is a runtime type. */ |
| if (TREE_CODE (type) == NOP_EXPR) |
| return type; |
| |
| /* We should have always inserted the data earlier. */ |
| return *type_to_runtime_map->get (type); |
| } |
| |
| |
| /* Represent an entry in @TTypes for either catch actions |
| or exception filter actions. */ |
| struct ttypes_filter { |
| tree t; |
| int filter; |
| }; |
| |
| /* Helper for ttypes_filter hashing. */ |
| |
| struct ttypes_filter_hasher : free_ptr_hash <ttypes_filter> |
| { |
| typedef tree_node *compare_type; |
| static inline hashval_t hash (const ttypes_filter *); |
| static inline bool equal (const ttypes_filter *, const tree_node *); |
| }; |
| |
| /* Compare ENTRY (a ttypes_filter entry in the hash table) with DATA |
| (a tree) for a @TTypes type node we are thinking about adding. */ |
| |
| inline bool |
| ttypes_filter_hasher::equal (const ttypes_filter *entry, const tree_node *data) |
| { |
| return entry->t == data; |
| } |
| |
| inline hashval_t |
| ttypes_filter_hasher::hash (const ttypes_filter *entry) |
| { |
| return TREE_HASH (entry->t); |
| } |
| |
| typedef hash_table<ttypes_filter_hasher> ttypes_hash_type; |
| |
| |
| /* Helper for ehspec hashing. */ |
| |
| struct ehspec_hasher : free_ptr_hash <ttypes_filter> |
| { |
| static inline hashval_t hash (const ttypes_filter *); |
| static inline bool equal (const ttypes_filter *, const ttypes_filter *); |
| }; |
| |
| /* Compare ENTRY with DATA (both struct ttypes_filter) for a @TTypes |
| exception specification list we are thinking about adding. */ |
| /* ??? Currently we use the type lists in the order given. Someone |
| should put these in some canonical order. */ |
| |
| inline bool |
| ehspec_hasher::equal (const ttypes_filter *entry, const ttypes_filter *data) |
| { |
| return type_list_equal (entry->t, data->t); |
| } |
| |
| /* Hash function for exception specification lists. */ |
| |
| inline hashval_t |
| ehspec_hasher::hash (const ttypes_filter *entry) |
| { |
| hashval_t h = 0; |
| tree list; |
| |
| for (list = entry->t; list ; list = TREE_CHAIN (list)) |
| h = (h << 5) + (h >> 27) + TREE_HASH (TREE_VALUE (list)); |
| return h; |
| } |
| |
| typedef hash_table<ehspec_hasher> ehspec_hash_type; |
| |
| |
| /* Add TYPE (which may be NULL) to cfun->eh->ttype_data, using TYPES_HASH |
| to speed up the search. Return the filter value to be used. */ |
| |
| static int |
| add_ttypes_entry (ttypes_hash_type *ttypes_hash, tree type) |
| { |
| struct ttypes_filter **slot, *n; |
| |
| slot = ttypes_hash->find_slot_with_hash (type, (hashval_t) TREE_HASH (type), |
| INSERT); |
| |
| if ((n = *slot) == NULL) |
| { |
| /* Filter value is a 1 based table index. */ |
| |
| n = XNEW (struct ttypes_filter); |
| n->t = type; |
| n->filter = vec_safe_length (cfun->eh->ttype_data) + 1; |
| *slot = n; |
| |
| vec_safe_push (cfun->eh->ttype_data, type); |
| } |
| |
| return n->filter; |
| } |
| |
| /* Add LIST to cfun->eh->ehspec_data, using EHSPEC_HASH and TYPES_HASH |
| to speed up the search. Return the filter value to be used. */ |
| |
| static int |
| add_ehspec_entry (ehspec_hash_type *ehspec_hash, ttypes_hash_type *ttypes_hash, |
| tree list) |
| { |
| struct ttypes_filter **slot, *n; |
| struct ttypes_filter dummy; |
| |
| dummy.t = list; |
| slot = ehspec_hash->find_slot (&dummy, INSERT); |
| |
| if ((n = *slot) == NULL) |
| { |
| int len; |
| |
| if (targetm.arm_eabi_unwinder) |
| len = vec_safe_length (cfun->eh->ehspec_data.arm_eabi); |
| else |
| len = vec_safe_length (cfun->eh->ehspec_data.other); |
| |
| /* Filter value is a -1 based byte index into a uleb128 buffer. */ |
| |
| n = XNEW (struct ttypes_filter); |
| n->t = list; |
| n->filter = -(len + 1); |
| *slot = n; |
| |
| /* Generate a 0 terminated list of filter values. */ |
| for (; list ; list = TREE_CHAIN (list)) |
| { |
| if (targetm.arm_eabi_unwinder) |
| vec_safe_push (cfun->eh->ehspec_data.arm_eabi, TREE_VALUE (list)); |
| else |
| { |
| /* Look up each type in the list and encode its filter |
| value as a uleb128. */ |
| push_uleb128 (&cfun->eh->ehspec_data.other, |
| add_ttypes_entry (ttypes_hash, TREE_VALUE (list))); |
| } |
| } |
| if (targetm.arm_eabi_unwinder) |
| vec_safe_push (cfun->eh->ehspec_data.arm_eabi, NULL_TREE); |
| else |
| vec_safe_push (cfun->eh->ehspec_data.other, (uchar)0); |
| } |
| |
| return n->filter; |
| } |
| |
| /* Generate the action filter values to be used for CATCH and |
| ALLOWED_EXCEPTIONS regions. When using dwarf2 exception regions, |
| we use lots of landing pads, and so every type or list can share |
| the same filter value, which saves table space. */ |
| |
| void |
| assign_filter_values (void) |
| { |
| int i; |
| eh_region r; |
| eh_catch c; |
| |
| vec_alloc (cfun->eh->ttype_data, 16); |
| if (targetm.arm_eabi_unwinder) |
| vec_alloc (cfun->eh->ehspec_data.arm_eabi, 64); |
| else |
| vec_alloc (cfun->eh->ehspec_data.other, 64); |
| |
| ehspec_hash_type ehspec (31); |
| ttypes_hash_type ttypes (31); |
| |
| for (i = 1; vec_safe_iterate (cfun->eh->region_array, i, &r); ++i) |
| { |
| if (r == NULL) |
| continue; |
| |
| switch (r->type) |
| { |
| case ERT_TRY: |
| for (c = r->u.eh_try.first_catch; c ; c = c->next_catch) |
| { |
| /* Whatever type_list is (NULL or true list), we build a list |
| of filters for the region. */ |
| c->filter_list = NULL_TREE; |
| |
| if (c->type_list != NULL) |
| { |
| /* Get a filter value for each of the types caught and store |
| them in the region's dedicated list. */ |
| tree tp_node = c->type_list; |
| |
| for ( ; tp_node; tp_node = TREE_CHAIN (tp_node)) |
| { |
| int flt |
| = add_ttypes_entry (&ttypes, TREE_VALUE (tp_node)); |
| tree flt_node = build_int_cst (integer_type_node, flt); |
| |
| c->filter_list |
| = tree_cons (NULL_TREE, flt_node, c->filter_list); |
| } |
| } |
| else |
| { |
| /* Get a filter value for the NULL list also since it |
| will need an action record anyway. */ |
| int flt = add_ttypes_entry (&ttypes, NULL); |
| tree flt_node = build_int_cst (integer_type_node, flt); |
| |
| c->filter_list |
| = tree_cons (NULL_TREE, flt_node, NULL); |
| } |
| } |
| break; |
| |
| case ERT_ALLOWED_EXCEPTIONS: |
| r->u.allowed.filter |
| = add_ehspec_entry (&ehspec, &ttypes, r->u.allowed.type_list); |
| break; |
| |
| default: |
| break; |
| } |
| } |
| } |
| |
| /* Emit SEQ into basic block just before INSN (that is assumed to be |
| first instruction of some existing BB and return the newly |
| produced block. */ |
| static basic_block |
| emit_to_new_bb_before (rtx_insn *seq, rtx_insn *insn) |
| { |
| rtx_insn *next, *last; |
| basic_block bb; |
| edge e; |
| edge_iterator ei; |
| |
| /* If there happens to be a fallthru edge (possibly created by cleanup_cfg |
| call), we don't want it to go into newly created landing pad or other EH |
| construct. */ |
| for (ei = ei_start (BLOCK_FOR_INSN (insn)->preds); (e = ei_safe_edge (ei)); ) |
| if (e->flags & EDGE_FALLTHRU) |
| force_nonfallthru (e); |
| else |
| ei_next (&ei); |
| |
| /* Make sure to put the location of INSN or a subsequent instruction on SEQ |
| to avoid inheriting the location of the previous instruction. */ |
| next = insn; |
| while (next && !NONDEBUG_INSN_P (next)) |
| next = NEXT_INSN (next); |
| if (next) |
| last = emit_insn_before_setloc (seq, insn, INSN_LOCATION (next)); |
| else |
| last = emit_insn_before (seq, insn); |
| if (BARRIER_P (last)) |
| last = PREV_INSN (last); |
| bb = create_basic_block (seq, last, BLOCK_FOR_INSN (insn)->prev_bb); |
| update_bb_for_insn (bb); |
| bb->flags |= BB_SUPERBLOCK; |
| return bb; |
| } |
| |
| /* A subroutine of dw2_build_landing_pads, also used for edge splitting |
| at the rtl level. Emit the code required by the target at a landing |
| pad for the given region. */ |
| |
| static void |
| expand_dw2_landing_pad_for_region (eh_region region) |
| { |
| if (targetm.have_exception_receiver ()) |
| emit_insn (targetm.gen_exception_receiver ()); |
| else if (targetm.have_nonlocal_goto_receiver ()) |
| emit_insn (targetm.gen_nonlocal_goto_receiver ()); |
| else |
| { /* Nothing */ } |
| |
| if (region->exc_ptr_reg) |
| emit_move_insn (region->exc_ptr_reg, |
| gen_rtx_REG (ptr_mode, EH_RETURN_DATA_REGNO (0))); |
| if (region->filter_reg) |
| emit_move_insn (region->filter_reg, |
| gen_rtx_REG (targetm.eh_return_filter_mode (), |
| EH_RETURN_DATA_REGNO (1))); |
| } |
| |
| /* Expand the extra code needed at landing pads for dwarf2 unwinding. */ |
| |
| static void |
| dw2_build_landing_pads (void) |
| { |
| int i; |
| eh_landing_pad lp; |
| int e_flags = EDGE_FALLTHRU; |
| |
| /* If we're going to partition blocks, we need to be able to add |
| new landing pads later, which means that we need to hold on to |
| the post-landing-pad block. Prevent it from being merged away. |
| We'll remove this bit after partitioning. */ |
| if (flag_reorder_blocks_and_partition) |
| e_flags |= EDGE_PRESERVE; |
| |
| for (i = 1; vec_safe_iterate (cfun->eh->lp_array, i, &lp); ++i) |
| { |
| basic_block bb; |
| rtx_insn *seq; |
| |
| if (lp == NULL || lp->post_landing_pad == NULL) |
| continue; |
| |
| start_sequence (); |
| |
| lp->landing_pad = gen_label_rtx (); |
| emit_label (lp->landing_pad); |
| LABEL_PRESERVE_P (lp->landing_pad) = 1; |
| |
| expand_dw2_landing_pad_for_region (lp->region); |
| |
| seq = get_insns (); |
| end_sequence (); |
| |
| bb = emit_to_new_bb_before (seq, label_rtx (lp->post_landing_pad)); |
| bb->count = bb->next_bb->count; |
| make_single_succ_edge (bb, bb->next_bb, e_flags); |
| if (current_loops) |
| { |
| class loop *loop = bb->next_bb->loop_father; |
| /* If we created a pre-header block, add the new block to the |
| outer loop, otherwise to the loop itself. */ |
| if (bb->next_bb == loop->header) |
| add_bb_to_loop (bb, loop_outer (loop)); |
| else |
| add_bb_to_loop (bb, loop); |
| } |
| } |
| } |
| |
| |
| static vec<int> sjlj_lp_call_site_index; |
| |
| /* Process all active landing pads. Assign each one a compact dispatch |
| index, and a call-site index. */ |
| |
| static int |
| sjlj_assign_call_site_values (void) |
| { |
| action_hash_type ar_hash (31); |
| int i, disp_index; |
| eh_landing_pad lp; |
| |
| vec_alloc (crtl->eh.action_record_data, 64); |
| |
| disp_index = 0; |
| call_site_base = 1; |
| for (i = 1; vec_safe_iterate (cfun->eh->lp_array, i, &lp); ++i) |
| if (lp && lp->post_landing_pad) |
| { |
| int action, call_site; |
| |
| /* First: build the action table. */ |
| action = collect_one_action_chain (&ar_hash, lp->region); |
| |
| /* Next: assign call-site values. If dwarf2 terms, this would be |
| the region number assigned by convert_to_eh_region_ranges, but |
| handles no-action and must-not-throw differently. */ |
| /* Map must-not-throw to otherwise unused call-site index 0. */ |
| if (action == -2) |
| call_site = 0; |
| /* Map no-action to otherwise unused call-site index -1. */ |
| else if (action == -1) |
| call_site = -1; |
| /* Otherwise, look it up in the table. */ |
| else |
| call_site = add_call_site (GEN_INT (disp_index), action, 0); |
| sjlj_lp_call_site_index[i] = call_site; |
| |
| disp_index++; |
| } |
| |
| return disp_index; |
| } |
| |
| /* Emit code to record the current call-site index before every |
| insn that can throw. */ |
| |
| static void |
| sjlj_mark_call_sites (void) |
| { |
| int last_call_site = -2; |
| rtx_insn *insn; |
| rtx mem; |
| |
| for (insn = get_insns (); insn ; insn = NEXT_INSN (insn)) |
| { |
| eh_landing_pad lp; |
| eh_region r; |
| bool nothrow; |
| int this_call_site; |
| rtx_insn *before, *p; |
| |
| /* Reset value tracking at extended basic block boundaries. */ |
| if (LABEL_P (insn)) |
| last_call_site = -2; |
| |
| /* If the function allocates dynamic stack space, the context must |
| be updated after every allocation/deallocation accordingly. */ |
| if (NOTE_P (insn) && NOTE_KIND (insn) == NOTE_INSN_UPDATE_SJLJ_CONTEXT) |
| { |
| rtx buf_addr; |
| |
| start_sequence (); |
| buf_addr = plus_constant (Pmode, XEXP (crtl->eh.sjlj_fc, 0), |
| sjlj_fc_jbuf_ofs); |
| expand_builtin_update_setjmp_buf (buf_addr); |
| p = get_insns (); |
| end_sequence (); |
| emit_insn_before (p, insn); |
| } |
| |
| if (! INSN_P (insn)) |
| continue; |
| |
| nothrow = get_eh_region_and_lp_from_rtx (insn, &r, &lp); |
| if (nothrow) |
| continue; |
| if (lp) |
| this_call_site = sjlj_lp_call_site_index[lp->index]; |
| else if (r == NULL) |
| { |
| /* Calls (and trapping insns) without notes are outside any |
| exception handling region in this function. Mark them as |
| no action. */ |
| this_call_site = -1; |
| } |
| else |
| { |
| gcc_assert (r->type == ERT_MUST_NOT_THROW); |
| this_call_site = 0; |
| } |
| |
| if (this_call_site != -1) |
| crtl->uses_eh_lsda = 1; |
| |
| if (this_call_site == last_call_site) |
| continue; |
| |
| /* Don't separate a call from it's argument loads. */ |
| before = insn; |
| if (CALL_P (insn)) |
| before = find_first_parameter_load (insn, NULL); |
| |
| start_sequence (); |
| mem = adjust_address (crtl->eh.sjlj_fc, TYPE_MODE (integer_type_node), |
| sjlj_fc_call_site_ofs); |
| emit_move_insn (mem, gen_int_mode (this_call_site, GET_MODE (mem))); |
| p = get_insns (); |
| end_sequence (); |
| |
| emit_insn_before (p, before); |
| last_call_site = this_call_site; |
| } |
| } |
| |
| /* Construct the SjLj_Function_Context. */ |
| |
| static void |
| sjlj_emit_function_enter (rtx_code_label *dispatch_label) |
| { |
| rtx_insn *fn_begin, *seq; |
| rtx fc, mem; |
| bool fn_begin_outside_block; |
| rtx personality = get_personality_function (current_function_decl); |
| |
| fc = crtl->eh.sjlj_fc; |
| |
| start_sequence (); |
| |
| /* We're storing this libcall's address into memory instead of |
| calling it directly. Thus, we must call assemble_external_libcall |
| here, as we cannot depend on emit_library_call to do it for us. */ |
| assemble_external_libcall (personality); |
| mem = adjust_address (fc, Pmode, sjlj_fc_personality_ofs); |
| emit_move_insn (mem, personality); |
| |
| mem = adjust_address (fc, Pmode, sjlj_fc_lsda_ofs); |
| if (crtl->uses_eh_lsda) |
| { |
| char buf[20]; |
| rtx sym; |
| |
| ASM_GENERATE_INTERNAL_LABEL (buf, "LLSDA", current_function_funcdef_no); |
| sym = gen_rtx_SYMBOL_REF (Pmode, ggc_strdup (buf)); |
| SYMBOL_REF_FLAGS (sym) = SYMBOL_FLAG_LOCAL; |
| emit_move_insn (mem, sym); |
| } |
| else |
| emit_move_insn (mem, const0_rtx); |
| |
| if (dispatch_label) |
| { |
| rtx addr = plus_constant (Pmode, XEXP (fc, 0), sjlj_fc_jbuf_ofs); |
| |
| #ifdef DONT_USE_BUILTIN_SETJMP |
| addr = copy_addr_to_reg (addr); |
| addr = convert_memory_address (ptr_mode, addr); |
| tree addr_tree = make_tree (ptr_type_node, addr); |
| |
| tree call_expr = build_call_expr (setjmp_fn, 1, addr_tree); |
| rtx x = expand_call (call_expr, NULL_RTX, false); |
| |
| emit_cmp_and_jump_insns (x, const0_rtx, NE, 0, |
| TYPE_MODE (integer_type_node), 0, |
| dispatch_label, |
| profile_probability::unlikely ()); |
| #else |
| expand_builtin_setjmp_setup (addr, dispatch_label); |
| #endif |
| } |
| |
| emit_library_call (unwind_sjlj_register_libfunc, LCT_NORMAL, VOIDmode, |
| XEXP (fc, 0), Pmode); |
| |
| seq = get_insns (); |
| end_sequence (); |
| |
| /* ??? Instead of doing this at the beginning of the function, |
| do this in a block that is at loop level 0 and dominates all |
| can_throw_internal instructions. */ |
| |
| fn_begin_outside_block = true; |
| for (fn_begin = get_insns (); ; fn_begin = NEXT_INSN (fn_begin)) |
| if (NOTE_P (fn_begin)) |
| { |
| if (NOTE_KIND (fn_begin) == NOTE_INSN_FUNCTION_BEG) |
| break; |
| else if (NOTE_INSN_BASIC_BLOCK_P (fn_begin)) |
| fn_begin_outside_block = false; |
| } |
| |
| #ifdef DONT_USE_BUILTIN_SETJMP |
| if (dispatch_label) |
| { |
| /* The sequence contains a branch in the middle so we need to force |
| the creation of a new basic block by means of BB_SUPERBLOCK. */ |
| if (fn_begin_outside_block) |
| { |
| basic_block bb |
| = split_edge (single_succ_edge (ENTRY_BLOCK_PTR_FOR_FN (cfun))); |
| if (JUMP_P (BB_END (bb))) |
| emit_insn_before (seq, BB_END (bb)); |
| else |
| emit_insn_after (seq, BB_END (bb)); |
| } |
| else |
| emit_insn_after (seq, fn_begin); |
| |
| single_succ (ENTRY_BLOCK_PTR_FOR_FN (cfun))->flags |= BB_SUPERBLOCK; |
| return; |
| } |
| #endif |
| |
| if (fn_begin_outside_block) |
| insert_insn_on_edge (seq, single_succ_edge (ENTRY_BLOCK_PTR_FOR_FN (cfun))); |
| else |
| emit_insn_after (seq, fn_begin); |
| } |
| |
| /* Call back from expand_function_end to know where we should put |
| the call to unwind_sjlj_unregister_libfunc if needed. */ |
| |
| void |
| sjlj_emit_function_exit_after (rtx_insn *after) |
| { |
| crtl->eh.sjlj_exit_after = after; |
| } |
| |
| static void |
| sjlj_emit_function_exit (void) |
| { |
| rtx_insn *seq, *insn; |
| |
| start_sequence (); |
| |
| emit_library_call (unwind_sjlj_unregister_libfunc, LCT_NORMAL, VOIDmode, |
| XEXP (crtl->eh.sjlj_fc, 0), Pmode); |
| |
| seq = get_insns (); |
| end_sequence (); |
| |
| /* ??? Really this can be done in any block at loop level 0 that |
| post-dominates all can_throw_internal instructions. This is |
| the last possible moment. */ |
| |
| insn = crtl->eh.sjlj_exit_after; |
| if (LABEL_P (insn)) |
| insn = NEXT_INSN (insn); |
| |
| emit_insn_after (seq, insn); |
| } |
| |
| static void |
| sjlj_emit_dispatch_table (rtx_code_label *dispatch_label, int num_dispatch) |
| { |
| scalar_int_mode unwind_word_mode = targetm.unwind_word_mode (); |
| scalar_int_mode filter_mode = targetm.eh_return_filter_mode (); |
| eh_landing_pad lp; |
| rtx mem, fc, exc_ptr_reg, filter_reg; |
| rtx_insn *seq; |
| basic_block bb; |
| eh_region r; |
| int i, disp_index; |
| vec<tree> dispatch_labels = vNULL; |
| |
| fc = crtl->eh.sjlj_fc; |
| |
| start_sequence (); |
| |
| emit_label (dispatch_label); |
| |
| #ifndef DONT_USE_BUILTIN_SETJMP |
| expand_builtin_setjmp_receiver (dispatch_label); |
| |
| /* The caller of expand_builtin_setjmp_receiver is responsible for |
| making sure that the label doesn't vanish. The only other caller |
| is the expander for __builtin_setjmp_receiver, which places this |
| label on the nonlocal_goto_label list. Since we're modeling these |
| CFG edges more exactly, we can use the forced_labels list instead. */ |
| LABEL_PRESERVE_P (dispatch_label) = 1; |
| vec_safe_push<rtx_insn *> (forced_labels, dispatch_label); |
| #endif |
| |
| /* Load up exc_ptr and filter values from the function context. */ |
| mem = adjust_address (fc, unwind_word_mode, sjlj_fc_data_ofs); |
| if (unwind_word_mode != ptr_mode) |
| { |
| #ifdef POINTERS_EXTEND_UNSIGNED |
| mem = convert_memory_address (ptr_mode, mem); |
| #else |
| mem = convert_to_mode (ptr_mode, mem, 0); |
| #endif |
| } |
| exc_ptr_reg = force_reg (ptr_mode, mem); |
| |
| mem = adjust_address (fc, unwind_word_mode, |
| sjlj_fc_data_ofs + GET_MODE_SIZE (unwind_word_mode)); |
| if (unwind_word_mode != filter_mode) |
| mem = convert_to_mode (filter_mode, mem, 0); |
| filter_reg = force_reg (filter_mode, mem); |
| |
| /* Jump to one of the directly reachable regions. */ |
| |
| disp_index = 0; |
| rtx_code_label *first_reachable_label = NULL; |
| |
| /* If there's exactly one call site in the function, don't bother |
| generating a switch statement. */ |
| if (num_dispatch > 1) |
| dispatch_labels.create (num_dispatch); |
| |
| for (i = 1; vec_safe_iterate (cfun->eh->lp_array, i, &lp); ++i) |
| if (lp && lp->post_landing_pad) |
| { |
| rtx_insn *seq2; |
| rtx_code_label *label; |
| |
| start_sequence (); |
| |
| lp->landing_pad = dispatch_label; |
| |
| if (num_dispatch > 1) |
| { |
| tree t_label, case_elt, t; |
| |
| t_label = create_artificial_label (UNKNOWN_LOCATION); |
| t = build_int_cst (integer_type_node, disp_index); |
| case_elt = build_case_label (t, NULL, t_label); |
| dispatch_labels.quick_push (case_elt); |
| label = jump_target_rtx (t_label); |
| } |
| else |
| label = gen_label_rtx (); |
| |
| if (disp_index == 0) |
| first_reachable_label = label; |
| emit_label (label); |
| |
| r = lp->region; |
| if (r->exc_ptr_reg) |
| emit_move_insn (r->exc_ptr_reg, exc_ptr_reg); |
| if (r->filter_reg) |
| emit_move_insn (r->filter_reg, filter_reg); |
| |
| seq2 = get_insns (); |
| end_sequence (); |
| |
| rtx_insn *before = label_rtx (lp->post_landing_pad); |
| bb = emit_to_new_bb_before (seq2, before); |
| make_single_succ_edge (bb, bb->next_bb, EDGE_FALLTHRU); |
| if (current_loops) |
| { |
| class loop *loop = bb->next_bb->loop_father; |
| /* If we created a pre-header block, add the new block to the |
| outer loop, otherwise to the loop itself. */ |
| if (bb->next_bb == loop->header) |
| add_bb_to_loop (bb, loop_outer (loop)); |
| else |
| add_bb_to_loop (bb, loop); |
| /* ??? For multiple dispatches we will end up with edges |
| from the loop tree root into this loop, making it a |
| multiple-entry loop. Discard all affected loops. */ |
| if (num_dispatch > 1) |
| { |
| for (loop = bb->loop_father; |
| loop_outer (loop); loop = loop_outer (loop)) |
| mark_loop_for_removal (loop); |
| } |
| } |
| |
| disp_index++; |
| } |
| gcc_assert (disp_index == num_dispatch); |
| |
| if (num_dispatch > 1) |
| { |
| rtx disp = adjust_address (fc, TYPE_MODE (integer_type_node), |
| sjlj_fc_call_site_ofs); |
| expand_sjlj_dispatch_table (disp, dispatch_labels); |
| } |
| |
| seq = get_insns (); |
| end_sequence (); |
| |
| bb = emit_to_new_bb_before (seq, first_reachable_label); |
| if (num_dispatch == 1) |
| { |
| make_single_succ_edge (bb, bb->next_bb, EDGE_FALLTHRU); |
| if (current_loops) |
| { |
| class loop *loop = bb->next_bb->loop_father; |
| /* If we created a pre-header block, add the new block to the |
| outer loop, otherwise to the loop itself. */ |
| if (bb->next_bb == loop->header) |
| add_bb_to_loop (bb, loop_outer (loop)); |
| else |
| add_bb_to_loop (bb, loop); |
| } |
| } |
| else |
| { |
| /* We are not wiring up edges here, but as the dispatcher call |
| is at function begin simply associate the block with the |
| outermost (non-)loop. */ |
| if (current_loops) |
| add_bb_to_loop (bb, current_loops->tree_root); |
| } |
| } |
| |
| static void |
| sjlj_build_landing_pads (void) |
| { |
| int num_dispatch; |
| |
| num_dispatch = vec_safe_length (cfun->eh->lp_array); |
| if (num_dispatch == 0) |
| return; |
| sjlj_lp_call_site_index.safe_grow_cleared (num_dispatch, true); |
| |
| num_dispatch = sjlj_assign_call_site_values (); |
| if (num_dispatch > 0) |
| { |
| rtx_code_label *dispatch_label = gen_label_rtx (); |
| int align = STACK_SLOT_ALIGNMENT (sjlj_fc_type_node, |
| TYPE_MODE (sjlj_fc_type_node), |
| TYPE_ALIGN (sjlj_fc_type_node)); |
| crtl->eh.sjlj_fc |
| = assign_stack_local (TYPE_MODE (sjlj_fc_type_node), |
| int_size_in_bytes (sjlj_fc_type_node), |
| align); |
| |
| sjlj_mark_call_sites (); |
| sjlj_emit_function_enter (dispatch_label); |
| sjlj_emit_dispatch_table (dispatch_label, num_dispatch); |
| sjlj_emit_function_exit (); |
| } |
| |
| /* If we do not have any landing pads, we may still need to register a |
| personality routine and (empty) LSDA to handle must-not-throw regions. */ |
| else if (function_needs_eh_personality (cfun) != eh_personality_none) |
| { |
| int align = STACK_SLOT_ALIGNMENT (sjlj_fc_type_node, |
| TYPE_MODE (sjlj_fc_type_node), |
| TYPE_ALIGN (sjlj_fc_type_node)); |
| crtl->eh.sjlj_fc |
| = assign_stack_local (TYPE_MODE (sjlj_fc_type_node), |
| int_size_in_bytes (sjlj_fc_type_node), |
| align); |
| |
| sjlj_mark_call_sites (); |
| sjlj_emit_function_enter (NULL); |
| sjlj_emit_function_exit (); |
| } |
| |
| sjlj_lp_call_site_index.release (); |
| } |
| |
| /* Update the sjlj function context. This function should be called |
| whenever we allocate or deallocate dynamic stack space. */ |
| |
| void |
| update_sjlj_context (void) |
| { |
| if (!flag_exceptions) |
| return; |
| |
| emit_note (NOTE_INSN_UPDATE_SJLJ_CONTEXT); |
| } |
| |
| /* After initial rtl generation, call back to finish generating |
| exception support code. */ |
| |
| void |
| finish_eh_generation (void) |
| { |
| basic_block bb; |
| |
| /* Construct the landing pads. */ |
| if (targetm_common.except_unwind_info (&global_options) == UI_SJLJ) |
| sjlj_build_landing_pads (); |
| else |
| dw2_build_landing_pads (); |
| |
| break_superblocks (); |
| |
| /* Redirect all EH edges from the post_landing_pad to the landing pad. */ |
| FOR_EACH_BB_FN (bb, cfun) |
| { |
| eh_landing_pad lp; |
| edge_iterator ei; |
| edge e; |
| |
| lp = get_eh_landing_pad_from_rtx (BB_END (bb)); |
| |
| FOR_EACH_EDGE (e, ei, bb->succs) |
| if (e->flags & EDGE_EH) |
| break; |
| |
| /* We should not have generated any new throwing insns during this |
| pass, and we should not have lost any EH edges, so we only need |
| to handle two cases here: |
| (1) reachable handler and an existing edge to post-landing-pad, |
| (2) no reachable handler and no edge. */ |
| gcc_assert ((lp != NULL) == (e != NULL)); |
| if (lp != NULL) |
| { |
| gcc_assert (BB_HEAD (e->dest) == label_rtx (lp->post_landing_pad)); |
| |
| redirect_edge_succ (e, BLOCK_FOR_INSN (lp->landing_pad)); |
| e->flags |= (CALL_P (BB_END (bb)) |
| ? EDGE_ABNORMAL | EDGE_ABNORMAL_CALL |
| : EDGE_ABNORMAL); |
| } |
| } |
| |
| if (targetm_common.except_unwind_info (&global_options) == UI_SJLJ |
| /* Kludge for Alpha (see alpha_gp_save_rtx). */ |
| || single_succ_edge (ENTRY_BLOCK_PTR_FOR_FN (cfun))->insns.r) |
| commit_edge_insertions (); |
| } |
| |
| /* This section handles removing dead code for flow. */ |
| |
| void |
| remove_eh_landing_pad (eh_landing_pad lp) |
| { |
| eh_landing_pad *pp; |
| |
| for (pp = &lp->region->landing_pads; *pp != lp; pp = &(*pp)->next_lp) |
| continue; |
| *pp = lp->next_lp; |
| |
| if (lp->post_landing_pad) |
| EH_LANDING_PAD_NR (lp->post_landing_pad) = 0; |
| (*cfun->eh->lp_array)[lp->index] = NULL; |
| } |
| |
| /* Splice the EH region at PP from the region tree. */ |
| |
| static void |
| remove_eh_handler_splicer (eh_region *pp) |
| { |
| eh_region region = *pp; |
| eh_landing_pad lp; |
| |
| for (lp = region->landing_pads; lp ; lp = lp->next_lp) |
| { |
| if (lp->post_landing_pad) |
| EH_LANDING_PAD_NR (lp->post_landing_pad) = 0; |
| (*cfun->eh->lp_array)[lp->index] = NULL; |
| } |
| |
| if (region->inner) |
| { |
| eh_region p, outer; |
| outer = region->outer; |
| |
| *pp = p = region->inner; |
| do |
| { |
| p->outer = outer; |
| pp = &p->next_peer; |
| p = *pp; |
| } |
| while (p); |
| } |
| *pp = region->next_peer; |
| |
| (*cfun->eh->region_array)[region->index] = NULL; |
| } |
| |
| /* Splice a single EH region REGION from the region tree. |
| |
| To unlink REGION, we need to find the pointer to it with a relatively |
| expensive search in REGION's outer region. If you are going to |
| remove a number of handlers, using remove_unreachable_eh_regions may |
| be a better option. */ |
| |
| void |
| remove_eh_handler (eh_region region) |
| { |
| eh_region *pp, *pp_start, p, outer; |
| |
| outer = region->outer; |
| if (outer) |
| pp_start = &outer->inner; |
| else |
| pp_start = &cfun->eh->region_tree; |
| for (pp = pp_start, p = *pp; p != region; pp = &p->next_peer, p = *pp) |
| continue; |
| |
| remove_eh_handler_splicer (pp); |
| } |
| |
| /* Worker for remove_unreachable_eh_regions. |
| PP is a pointer to the region to start a region tree depth-first |
| search from. R_REACHABLE is the set of regions that have to be |
| preserved. */ |
| |
| static void |
| remove_unreachable_eh_regions_worker (eh_region *pp, sbitmap r_reachable) |
| { |
| while (*pp) |
| { |
| eh_region region = *pp; |
| remove_unreachable_eh_regions_worker (®ion->inner, r_reachable); |
| if (!bitmap_bit_p (r_reachable, region->index)) |
| remove_eh_handler_splicer (pp); |
| else |
| pp = ®ion->next_peer; |
| } |
| } |
| |
| /* Splice all EH regions *not* marked in R_REACHABLE from the region tree. |
| Do this by traversing the EH tree top-down and splice out regions that |
| are not marked. By removing regions from the leaves, we avoid costly |
| searches in the region tree. */ |
| |
| void |
| remove_unreachable_eh_regions (sbitmap r_reachable) |
| { |
| remove_unreachable_eh_regions_worker (&cfun->eh->region_tree, r_reachable); |
| } |
| |
| /* Invokes CALLBACK for every exception handler landing pad label. |
| Only used by reload hackery; should not be used by new code. */ |
| |
| void |
| for_each_eh_label (void (*callback) (rtx)) |
| { |
| eh_landing_pad lp; |
| int i; |
| |
| for (i = 1; vec_safe_iterate (cfun->eh->lp_array, i, &lp); ++i) |
| { |
| if (lp) |
| { |
| rtx_code_label *lab = lp->landing_pad; |
| if (lab && LABEL_P (lab)) |
| (*callback) (lab); |
| } |
| } |
| } |
| |
| /* Create the REG_EH_REGION note for INSN, given its ECF_FLAGS for a |
| call insn. |
| |
| At the gimple level, we use LP_NR |
| > 0 : The statement transfers to landing pad LP_NR |
| = 0 : The statement is outside any EH region |
| < 0 : The statement is within MUST_NOT_THROW region -LP_NR. |
| |
| At the rtl level, we use LP_NR |
| > 0 : The insn transfers to landing pad LP_NR |
| = 0 : The insn cannot throw |
| < 0 : The insn is within MUST_NOT_THROW region -LP_NR |
| = INT_MIN : The insn cannot throw or execute a nonlocal-goto. |
| missing note: The insn is outside any EH region. |
| |
| ??? This difference probably ought to be avoided. We could stand |
| to record nothrow for arbitrary gimple statements, and so avoid |
| some moderately complex lookups in stmt_could_throw_p. Perhaps |
| NOTHROW should be mapped on both sides to INT_MIN. Perhaps the |
| no-nonlocal-goto property should be recorded elsewhere as a bit |
| on the call_insn directly. Perhaps we should make more use of |
| attaching the trees to call_insns (reachable via symbol_ref in |
| direct call cases) and just pull the data out of the trees. */ |
| |
| void |
| make_reg_eh_region_note (rtx_insn *insn, int ecf_flags, int lp_nr) |
| { |
| rtx value; |
| if (ecf_flags & ECF_NOTHROW) |
| value = const0_rtx; |
| else if (lp_nr != 0) |
| value = GEN_INT (lp_nr); |
| else |
| return; |
| add_reg_note (insn, REG_EH_REGION, value); |
| } |
| |
| /* Create a REG_EH_REGION note for a CALL_INSN that cannot throw |
| nor perform a non-local goto. Replace the region note if it |
| already exists. */ |
| |
| void |
| make_reg_eh_region_note_nothrow_nononlocal (rtx_insn *insn) |
| { |
| rtx note = find_reg_note (insn, REG_EH_REGION, NULL_RTX); |
| rtx intmin = GEN_INT (INT_MIN); |
| |
| if (note != 0) |
| XEXP (note, 0) = intmin; |
| else |
| add_reg_note (insn, REG_EH_REGION, intmin); |
| } |
| |
| /* Return true if INSN could throw, assuming no REG_EH_REGION note |
| to the contrary. */ |
| |
| bool |
| insn_could_throw_p (const_rtx insn) |
| { |
| if (!flag_exceptions) |
| return false; |
| if (CALL_P (insn)) |
| return true; |
| if (INSN_P (insn) && cfun->can_throw_non_call_exceptions) |
| return may_trap_p (PATTERN (insn)); |
| return false; |
| } |
| |
| /* Copy an REG_EH_REGION note to each insn that might throw beginning |
| at FIRST and ending at LAST. NOTE_OR_INSN is either the source insn |
| to look for a note, or the note itself. */ |
| |
| void |
| copy_reg_eh_region_note_forward (rtx note_or_insn, rtx_insn *first, rtx last) |
| { |
| rtx_insn *insn; |
| rtx note = note_or_insn; |
| |
| if (INSN_P (note_or_insn)) |
| { |
| note = find_reg_note (note_or_insn, REG_EH_REGION, NULL_RTX); |
| if (note == NULL) |
| return; |
| } |
| else if (is_a <rtx_insn *> (note_or_insn)) |
| return; |
| note = XEXP (note, 0); |
| |
| for (insn = first; insn != last ; insn = NEXT_INSN (insn)) |
| if (!find_reg_note (insn, REG_EH_REGION, NULL_RTX) |
| && insn_could_throw_p (insn)) |
| add_reg_note (insn, REG_EH_REGION, note); |
| } |
| |
| /* Likewise, but iterate backward. */ |
| |
| void |
| copy_reg_eh_region_note_backward (rtx note_or_insn, rtx_insn *last, rtx first) |
| { |
| rtx_insn *insn; |
| rtx note = note_or_insn; |
| |
| if (INSN_P (note_or_insn)) |
| { |
| note = find_reg_note (note_or_insn, REG_EH_REGION, NULL_RTX); |
| if (note == NULL) |
| return; |
| } |
| else if (is_a <rtx_insn *> (note_or_insn)) |
| return; |
| note = XEXP (note, 0); |
| |
| for (insn = last; insn != first; insn = PREV_INSN (insn)) |
| if (insn_could_throw_p (insn)) |
| add_reg_note (insn, REG_EH_REGION, note); |
| } |
| |
| |
| /* Extract all EH information from INSN. Return true if the insn |
| was marked NOTHROW. */ |
| |
| static bool |
| get_eh_region_and_lp_from_rtx (const_rtx insn, eh_region *pr, |
| eh_landing_pad *plp) |
| { |
| eh_landing_pad lp = NULL; |
| eh_region r = NULL; |
| bool ret = false; |
| rtx note; |
| int lp_nr; |
| |
| if (! INSN_P (insn)) |
| goto egress; |
| |
| if (NONJUMP_INSN_P (insn) |
| && GET_CODE (PATTERN (insn)) == SEQUENCE) |
| insn = XVECEXP (PATTERN (insn), 0, 0); |
| |
| note = find_reg_note (insn, REG_EH_REGION, NULL_RTX); |
| if (!note) |
| { |
| ret = !insn_could_throw_p (insn); |
| goto egress; |
| } |
| |
| lp_nr = INTVAL (XEXP (note, 0)); |
| if (lp_nr == 0 || lp_nr == INT_MIN) |
| { |
| ret = true; |
| goto egress; |
| } |
| |
| if (lp_nr < 0) |
| r = (*cfun->eh->region_array)[-lp_nr]; |
| else |
| { |
| lp = (*cfun->eh->lp_array)[lp_nr]; |
| r = lp->region; |
| } |
| |
| egress: |
| *plp = lp; |
| *pr = r; |
| return ret; |
| } |
| |
| /* Return the landing pad to which INSN may go, or NULL if it does not |
| have a reachable landing pad within this function. */ |
| |
| eh_landing_pad |
| get_eh_landing_pad_from_rtx (const_rtx insn) |
| { |
| eh_landing_pad lp; |
| eh_region r; |
| |
| get_eh_region_and_lp_from_rtx (insn, &r, &lp); |
| return lp; |
| } |
| |
| /* Return the region to which INSN may go, or NULL if it does not |
| have a reachable region within this function. */ |
| |
| eh_region |
| get_eh_region_from_rtx (const_rtx insn) |
| { |
| eh_landing_pad lp; |
| eh_region r; |
| |
| get_eh_region_and_lp_from_rtx (insn, &r, &lp); |
| return r; |
| } |
| |
| /* Return true if INSN throws and is caught by something in this function. */ |
| |
| bool |
| can_throw_internal (const_rtx insn) |
| { |
| return get_eh_landing_pad_from_rtx (insn) != NULL; |
| } |
| |
| /* Return true if INSN throws and escapes from the current function. */ |
| |
| bool |
| can_throw_external (const_rtx insn) |
| { |
| eh_landing_pad lp; |
| eh_region r; |
| bool nothrow; |
| |
| if (! INSN_P (insn)) |
| return false; |
| |
| if (NONJUMP_INSN_P (insn) |
| && GET_CODE (PATTERN (insn)) == SEQUENCE) |
| { |
| rtx_sequence *seq = as_a <rtx_sequence *> (PATTERN (insn)); |
| int i, n = seq->len (); |
| |
| for (i = 0; i < n; i++) |
| if (can_throw_external (seq->element (i))) |
| return true; |
| |
| return false; |
| } |
| |
| nothrow = get_eh_region_and_lp_from_rtx (insn, &r, &lp); |
| |
| /* If we can't throw, we obviously can't throw external. */ |
| if (nothrow) |
| return false; |
| |
| /* If we have an internal landing pad, then we're not external. */ |
| if (lp != NULL) |
| return false; |
| |
| /* If we're not within an EH region, then we are external. */ |
| if (r == NULL) |
| return true; |
| |
| /* The only thing that ought to be left is MUST_NOT_THROW regions, |
| which don't always have landing pads. */ |
| gcc_assert (r->type == ERT_MUST_NOT_THROW); |
| return false; |
| } |
| |
| /* Return true if INSN cannot throw at all. */ |
| |
| bool |
| insn_nothrow_p (const_rtx insn) |
| { |
| eh_landing_pad lp; |
| eh_region r; |
| |
| if (! INSN_P (insn)) |
| return true; |
| |
| if (NONJUMP_INSN_P (insn) |
| && GET_CODE (PATTERN (insn)) == SEQUENCE) |
| { |
| rtx_sequence *seq = as_a <rtx_sequence *> (PATTERN (insn)); |
| int i, n = seq->len (); |
| |
| for (i = 0; i < n; i++) |
| if (!insn_nothrow_p (seq->element (i))) |
| return false; |
| |
| return true; |
| } |
| |
| return get_eh_region_and_lp_from_rtx (insn, &r, &lp); |
| } |
| |
| /* Return true if INSN can perform a non-local goto. */ |
| /* ??? This test is here in this file because it (ab)uses REG_EH_REGION. */ |
| |
| bool |
| can_nonlocal_goto (const rtx_insn *insn) |
| { |
| if (nonlocal_goto_handler_labels && CALL_P (insn)) |
| { |
| rtx note = find_reg_note (insn, REG_EH_REGION, NULL_RTX); |
| if (!note || INTVAL (XEXP (note, 0)) != INT_MIN) |
| return true; |
| } |
| return false; |
| } |
| |
| /* Set TREE_NOTHROW and crtl->all_throwers_are_sibcalls. */ |
| |
| static unsigned int |
| set_nothrow_function_flags (void) |
| { |
| rtx_insn *insn; |
| |
| crtl->nothrow = 1; |
| |
| /* Assume crtl->all_throwers_are_sibcalls until we encounter |
| something that can throw an exception. We specifically exempt |
| CALL_INSNs that are SIBLING_CALL_P, as these are really jumps, |
| and can't throw. Most CALL_INSNs are not SIBLING_CALL_P, so this |
| is optimistic. */ |
| |
| crtl->all_throwers_are_sibcalls = 1; |
| |
| /* If we don't know that this implementation of the function will |
| actually be used, then we must not set TREE_NOTHROW, since |
| callers must not assume that this function does not throw. */ |
| if (TREE_NOTHROW (current_function_decl)) |
| return 0; |
| |
| if (! flag_exceptions) |
| return 0; |
| |
| for (insn = get_insns (); insn; insn = NEXT_INSN (insn)) |
| if (can_throw_external (insn)) |
| { |
| crtl->nothrow = 0; |
| |
| if (!CALL_P (insn) || !SIBLING_CALL_P (insn)) |
| { |
| crtl->all_throwers_are_sibcalls = 0; |
| return 0; |
| } |
| } |
| |
| if (crtl->nothrow |
| && (cgraph_node::get (current_function_decl)->get_availability () |
| >= AVAIL_AVAILABLE)) |
| { |
| struct cgraph_node *node = cgraph_node::get (current_function_decl); |
| struct cgraph_edge *e; |
| for (e = node->callers; e; e = e->next_caller) |
| e->can_throw_external = false; |
| node->set_nothrow_flag (true); |
| |
| if (dump_file) |
| fprintf (dump_file, "Marking function nothrow: %s\n\n", |
| current_function_name ()); |
| } |
| return 0; |
| } |
| |
| namespace { |
| |
| const pass_data pass_data_set_nothrow_function_flags = |
| { |
| RTL_PASS, /* type */ |
| "nothrow", /* name */ |
| OPTGROUP_NONE, /* optinfo_flags */ |
| TV_NONE, /* tv_id */ |
| 0, /* properties_required */ |
| 0, /* properties_provided */ |
| 0, /* properties_destroyed */ |
| 0, /* todo_flags_start */ |
| 0, /* todo_flags_finish */ |
| }; |
| |
| class pass_set_nothrow_function_flags : public rtl_opt_pass |
| { |
| public: |
| pass_set_nothrow_function_flags (gcc::context *ctxt) |
| : rtl_opt_pass (pass_data_set_nothrow_function_flags, ctxt) |
| {} |
| |
| /* opt_pass methods: */ |
| virtual unsigned int execute (function *) |
| { |
| return set_nothrow_function_flags (); |
| } |
| |
| }; // class pass_set_nothrow_function_flags |
| |
| } // anon namespace |
| |
| rtl_opt_pass * |
| make_pass_set_nothrow_function_flags (gcc::context *ctxt) |
| { |
| return new pass_set_nothrow_function_flags (ctxt); |
| } |
| |
| |
| /* Various hooks for unwind library. */ |
| |
| /* Expand the EH support builtin functions: |
| __builtin_eh_pointer and __builtin_eh_filter. */ |
| |
| static eh_region |
| expand_builtin_eh_common (tree region_nr_t) |
| { |
| HOST_WIDE_INT region_nr; |
| eh_region region; |
| |
| gcc_assert (tree_fits_shwi_p (region_nr_t)); |
| region_nr = tree_to_shwi (region_nr_t); |
| |
| region = (*cfun->eh->region_array)[region_nr]; |
| |
| /* ??? We shouldn't have been able to delete a eh region without |
| deleting all the code that depended on it. */ |
| gcc_assert (region != NULL); |
| |
| return region; |
| } |
| |
| /* Expand to the exc_ptr value from the given eh region. */ |
| |
| rtx |
| expand_builtin_eh_pointer (tree exp) |
| { |
| eh_region region |
| = expand_builtin_eh_common (CALL_EXPR_ARG (exp, 0)); |
| if (region->exc_ptr_reg == NULL) |
| region->exc_ptr_reg = gen_reg_rtx (ptr_mode); |
| return region->exc_ptr_reg; |
| } |
| |
| /* Expand to the filter value from the given eh region. */ |
| |
| rtx |
| expand_builtin_eh_filter (tree exp) |
| { |
| eh_region region |
| = expand_builtin_eh_common (CALL_EXPR_ARG (exp, 0)); |
| if (region->filter_reg == NULL) |
| region->filter_reg = gen_reg_rtx (targetm.eh_return_filter_mode ()); |
| return region->filter_reg; |
| } |
| |
| /* Copy the exc_ptr and filter values from one landing pad's registers |
| to another. This is used to inline the resx statement. */ |
| |
| rtx |
| expand_builtin_eh_copy_values (tree exp) |
| { |
| eh_region dst |
| = expand_builtin_eh_common (CALL_EXPR_ARG (exp, 0)); |
| eh_region src |
| = expand_builtin_eh_common (CALL_EXPR_ARG (exp, 1)); |
| scalar_int_mode fmode = targetm.eh_return_filter_mode (); |
| |
| if (dst->exc_ptr_reg == NULL) |
| dst->exc_ptr_reg = gen_reg_rtx (ptr_mode); |
| if (src->exc_ptr_reg == NULL) |
| src->exc_ptr_reg = gen_reg_rtx (ptr_mode); |
| |
| if (dst->filter_reg == NULL) |
| dst->filter_reg = gen_reg_rtx (fmode); |
| if (src->filter_reg == NULL) |
| src->filter_reg = gen_reg_rtx (fmode); |
| |
| emit_move_insn (dst->exc_ptr_reg, src->exc_ptr_reg); |
| emit_move_insn (dst->filter_reg, src->filter_reg); |
| |
| return const0_rtx; |
| } |
| |
| /* Do any necessary initialization to access arbitrary stack frames. |
| On the SPARC, this means flushing the register windows. */ |
| |
| void |
| expand_builtin_unwind_init (void) |
| { |
| /* Set this so all the registers get saved in our frame; we need to be |
| able to copy the saved values for any registers from frames we unwind. */ |
| crtl->saves_all_registers = 1; |
| |
| SETUP_FRAME_ADDRESSES (); |
| } |
| |
| /* Map a non-negative number to an eh return data register number; expands |
| to -1 if no return data register is associated with the input number. |
| At least the inputs 0 and 1 must be mapped; the target may provide more. */ |
| |
| rtx |
| expand_builtin_eh_return_data_regno (tree exp) |
| { |
| tree which = CALL_EXPR_ARG (exp, 0); |
| unsigned HOST_WIDE_INT iwhich; |
| |
| if (TREE_CODE (which) != INTEGER_CST) |
| { |
| error ("argument of %<__builtin_eh_return_regno%> must be constant"); |
| return constm1_rtx; |
| } |
| |
| iwhich = tree_to_uhwi (which); |
| iwhich = EH_RETURN_DATA_REGNO (iwhich); |
| if (iwhich == INVALID_REGNUM) |
| return constm1_rtx; |
| |
| #ifdef DWARF_FRAME_REGNUM |
| iwhich = DWARF_FRAME_REGNUM (iwhich); |
| #else |
| iwhich = DBX_REGISTER_NUMBER (iwhich); |
| #endif |
| |
| return GEN_INT (iwhich); |
| } |
| |
| /* Given a value extracted from the return address register or stack slot, |
| return the actual address encoded in that value. */ |
| |
| rtx |
| expand_builtin_extract_return_addr (tree addr_tree) |
| { |
| rtx addr = expand_expr (addr_tree, NULL_RTX, Pmode, EXPAND_NORMAL); |
| |
| if (GET_MODE (addr) != Pmode |
| && GET_MODE (addr) != VOIDmode) |
| { |
| #ifdef POINTERS_EXTEND_UNSIGNED |
| addr = convert_memory_address (Pmode, addr); |
| #else |
| addr = convert_to_mode (Pmode, addr, 0); |
| #endif |
| } |
| |
| /* First mask out any unwanted bits. */ |
| rtx mask = MASK_RETURN_ADDR; |
| if (mask) |
| expand_and (Pmode, addr, mask, addr); |
| |
| /* Then adjust to find the real return address. */ |
| if (RETURN_ADDR_OFFSET) |
| addr = plus_constant (Pmode, addr, RETURN_ADDR_OFFSET); |
| |
| return addr; |
| } |
| |
| /* Given an actual address in addr_tree, do any necessary encoding |
| and return the value to be stored in the return address register or |
| stack slot so the epilogue will return to that address. */ |
| |
| rtx |
| expand_builtin_frob_return_addr (tree addr_tree) |
| { |
| rtx addr = expand_expr (addr_tree, NULL_RTX, ptr_mode, EXPAND_NORMAL); |
| |
| addr = convert_memory_address (Pmode, addr); |
| |
| if (RETURN_ADDR_OFFSET) |
| { |
| addr = force_reg (Pmode, addr); |
| addr = plus_constant (Pmode, addr, -RETURN_ADDR_OFFSET); |
| } |
| |
| return addr; |
| } |
| |
| /* Set up the epilogue with the magic bits we'll need to return to the |
| exception handler. */ |
| |
| void |
| expand_builtin_eh_return (tree stackadj_tree ATTRIBUTE_UNUSED, |
| tree handler_tree) |
| { |
| rtx tmp; |
| |
| #ifdef EH_RETURN_STACKADJ_RTX |
| tmp = expand_expr (stackadj_tree, crtl->eh.ehr_stackadj, |
| VOIDmode, EXPAND_NORMAL); |
| tmp = convert_memory_address (Pmode, tmp); |
| if (!crtl->eh.ehr_stackadj) |
| crtl->eh.ehr_stackadj = copy_addr_to_reg (tmp); |
| else if (tmp != crtl->eh.ehr_stackadj) |
| emit_move_insn (crtl->eh.ehr_stackadj, tmp); |
| #endif |
| |
| tmp = expand_expr (handler_tree, crtl->eh.ehr_handler, |
| VOIDmode, EXPAND_NORMAL); |
| tmp = convert_memory_address (Pmode, tmp); |
| if (!crtl->eh.ehr_handler) |
| crtl->eh.ehr_handler = copy_addr_to_reg (tmp); |
| else if (tmp != crtl->eh.ehr_handler) |
| emit_move_insn (crtl->eh.ehr_handler, tmp); |
| |
| if (!crtl->eh.ehr_label) |
| crtl->eh.ehr_label = gen_label_rtx (); |
| emit_jump (crtl->eh.ehr_label); |
| } |
| |
| /* Expand __builtin_eh_return. This exit path from the function loads up |
| the eh return data registers, adjusts the stack, and branches to a |
| given PC other than the normal return address. */ |
| |
| void |
| expand_eh_return (void) |
| { |
| rtx_code_label *around_label; |
| |
| if (! crtl->eh.ehr_label) |
| return; |
| |
| crtl->calls_eh_return = 1; |
| |
| #ifdef EH_RETURN_STACKADJ_RTX |
| emit_move_insn (EH_RETURN_STACKADJ_RTX, const0_rtx); |
| #endif |
| |
| around_label = gen_label_rtx (); |
| emit_jump (around_label); |
| |
| emit_label (crtl->eh.ehr_label); |
| clobber_return_register (); |
| |
| #ifdef EH_RETURN_STACKADJ_RTX |
| emit_move_insn (EH_RETURN_STACKADJ_RTX, crtl->eh.ehr_stackadj); |
| #endif |
| |
| if (targetm.have_eh_return ()) |
| emit_insn (targetm.gen_eh_return (crtl->eh.ehr_handler)); |
| else |
| { |
| if (rtx handler = EH_RETURN_HANDLER_RTX) |
| emit_move_insn (handler, crtl->eh.ehr_handler); |
| else |
| error ("%<__builtin_eh_return%> not supported on this target"); |
| } |
| |
| emit_label (around_label); |
| } |
| |
| /* Convert a ptr_mode address ADDR_TREE to a Pmode address controlled by |
| POINTERS_EXTEND_UNSIGNED and return it. */ |
| |
| rtx |
| expand_builtin_extend_pointer (tree addr_tree) |
| { |
| rtx addr = expand_expr (addr_tree, NULL_RTX, ptr_mode, EXPAND_NORMAL); |
| int extend; |
| |
| #ifdef POINTERS_EXTEND_UNSIGNED |
| extend = POINTERS_EXTEND_UNSIGNED; |
| #else |
| /* The previous EH code did an unsigned extend by default, so we do this also |
| for consistency. */ |
| extend = 1; |
| #endif |
| |
| return convert_modes (targetm.unwind_word_mode (), ptr_mode, addr, extend); |
| } |
| |
| static int |
| add_action_record (action_hash_type *ar_hash, int filter, int next) |
| { |
| struct action_record **slot, *new_ar, tmp; |
| |
| tmp.filter = filter; |
| tmp.next = next; |
| slot = ar_hash->find_slot (&tmp, INSERT); |
| |
| if ((new_ar = *slot) == NULL) |
| { |
| new_ar = XNEW (struct action_record); |
| new_ar->offset = crtl->eh.action_record_data->length () + 1; |
| new_ar->filter = filter; |
| new_ar->next = next; |
| *slot = new_ar; |
| |
| /* The filter value goes in untouched. The link to the next |
| record is a "self-relative" byte offset, or zero to indicate |
| that there is no next record. So convert the absolute 1 based |
| indices we've been carrying around into a displacement. */ |
| |
| push_sleb128 (&crtl->eh.action_record_data, filter); |
| if (next) |
| next -= crtl->eh.action_record_data->length () + 1; |
| push_sleb128 (&crtl->eh.action_record_data, next); |
| } |
| |
| return new_ar->offset; |
| } |
| |
| static int |
| collect_one_action_chain (action_hash_type *ar_hash, eh_region region) |
| { |
| int next; |
| |
| /* If we've reached the top of the region chain, then we have |
| no actions, and require no landing pad. */ |
| if (region == NULL) |
| return -1; |
| |
| switch (region->type) |
| { |
| case ERT_CLEANUP: |
| { |
| eh_region r; |
| /* A cleanup adds a zero filter to the beginning of the chain, but |
| there are special cases to look out for. If there are *only* |
| cleanups along a path, then it compresses to a zero action. |
| Further, if there are multiple cleanups along a path, we only |
| need to represent one of them, as that is enough to trigger |
| entry to the landing pad at runtime. */ |
| next = collect_one_action_chain (ar_hash, region->outer); |
| if (next <= 0) |
| return 0; |
| for (r = region->outer; r ; r = r->outer) |
| if (r->type == ERT_CLEANUP) |
| return next; |
| return add_action_record (ar_hash, 0, next); |
| } |
| |
| case ERT_TRY: |
| { |
| eh_catch c; |
| |
| /* Process the associated catch regions in reverse order. |
| If there's a catch-all handler, then we don't need to |
| search outer regions. Use a magic -3 value to record |
| that we haven't done the outer search. */ |
| next = -3; |
| for (c = region->u.eh_try.last_catch; c ; c = c->prev_catch) |
| { |
| if (c->type_list == NULL) |
| { |
| /* Retrieve the filter from the head of the filter list |
| where we have stored it (see assign_filter_values). */ |
| int filter = TREE_INT_CST_LOW (TREE_VALUE (c->filter_list)); |
| next = add_action_record (ar_hash, filter, 0); |
| } |
| else |
| { |
| /* Once the outer search is done, trigger an action record for |
| each filter we have. */ |
| tree flt_node; |
| |
| if (next == -3) |
| { |
| next = collect_one_action_chain (ar_hash, region->outer); |
| |
| /* If there is no next action, terminate the chain. */ |
| if (next == -1) |
| next = 0; |
| /* If all outer actions are cleanups or must_not_throw, |
| we'll have no action record for it, since we had wanted |
| to encode these states in the call-site record directly. |
| Add a cleanup action to the chain to catch these. */ |
| else if (next <= 0) |
| next = add_action_record (ar_hash, 0, 0); |
| } |
| |
| flt_node = c->filter_list; |
| for (; flt_node; flt_node = TREE_CHAIN (flt_node)) |
| { |
| int filter = TREE_INT_CST_LOW (TREE_VALUE (flt_node)); |
| next = add_action_record (ar_hash, filter, next); |
| } |
| } |
| } |
| return next; |
| } |
| |
| case ERT_ALLOWED_EXCEPTIONS: |
| /* An exception specification adds its filter to the |
| beginning of the chain. */ |
| next = collect_one_action_chain (ar_hash, region->outer); |
| |
| /* If there is no next action, terminate the chain. */ |
| if (next == -1) |
| next = 0; |
| /* If all outer actions are cleanups or must_not_throw, |
| we'll have no action record for it, since we had wanted |
| to encode these states in the call-site record directly. |
| Add a cleanup action to the chain to catch these. */ |
| else if (next <= 0) |
| next = add_action_record (ar_hash, 0, 0); |
| |
| return add_action_record (ar_hash, region->u.allowed.filter, next); |
| |
| case ERT_MUST_NOT_THROW: |
| /* A must-not-throw region with no inner handlers or cleanups |
| requires no call-site entry. Note that this differs from |
| the no handler or cleanup case in that we do require an lsda |
| to be generated. Return a magic -2 value to record this. */ |
| return -2; |
| } |
| |
| gcc_unreachable (); |
| } |
| |
| static int |
| add_call_site (rtx landing_pad, int action, int section) |
| { |
| call_site_record record; |
| |
| record = ggc_alloc<call_site_record_d> (); |
| record->landing_pad = landing_pad; |
| record->action = action; |
| |
| vec_safe_push (crtl->eh.call_site_record_v[section], record); |
| |
| return call_site_base + crtl->eh.call_site_record_v[section]->length () - 1; |
| } |
| |
| static rtx_note * |
| emit_note_eh_region_end (rtx_insn *insn) |
| { |
| return emit_note_after (NOTE_INSN_EH_REGION_END, insn); |
| } |
| |
| /* Add NOP after NOTE_INSN_SWITCH_TEXT_SECTIONS when the cold section starts |
| with landing pad. |
| With landing pad being at offset 0 from the start label of the section |
| we would miss EH delivery because 0 is special and means no landing pad. */ |
| |
| static bool |
| maybe_add_nop_after_section_switch (void) |
| { |
| if (!crtl->uses_eh_lsda |
| || !crtl->eh.call_site_record_v[1]) |
| return false; |
| int n = vec_safe_length (crtl->eh.call_site_record_v[1]); |
| hash_set<rtx_insn *> visited; |
| |
| for (int i = 0; i < n; ++i) |
| { |
| struct call_site_record_d *cs |
| = (*crtl->eh.call_site_record_v[1])[i]; |
| if (cs->landing_pad) |
| { |
| rtx_insn *insn = as_a <rtx_insn *> (cs->landing_pad); |
| while (true) |
| { |
| /* Landing pads have LABEL_PRESERVE_P flag set. This check make |
| sure that we do not walk past landing pad visited earlier |
| which would result in possible quadratic behaviour. */ |
| if (LABEL_P (insn) && LABEL_PRESERVE_P (insn) |
| && visited.add (insn)) |
| break; |
| |
| /* Conservatively assume that ASM insn may be empty. We have |
| now way to tell what they contain. */ |
| if (active_insn_p (insn) |
| && GET_CODE (PATTERN (insn)) != ASM_INPUT |
| && GET_CODE (PATTERN (insn)) != ASM_OPERANDS) |
| break; |
| |
| /* If we reached the start of hot section, then NOP will be |
| needed. */ |
| if (GET_CODE (insn) == NOTE |
| && NOTE_KIND (insn) == NOTE_INSN_SWITCH_TEXT_SECTIONS) |
| { |
| emit_insn_after (gen_nop (), insn); |
| break; |
| } |
| |
| /* We visit only labels from cold section. We should never hit |
| begining of the insn stream here. */ |
| insn = PREV_INSN (insn); |
| } |
| } |
| } |
| return false; |
| } |
| |
| /* Turn REG_EH_REGION notes back into NOTE_INSN_EH_REGION notes. |
| The new note numbers will not refer to region numbers, but |
| instead to call site entries. */ |
| |
| static unsigned int |
| convert_to_eh_region_ranges (void) |
| { |
| rtx insn; |
| rtx_insn *iter; |
| rtx_note *note; |
| action_hash_type ar_hash (31); |
| int last_action = -3; |
| rtx_insn *last_action_insn = NULL; |
| rtx last_landing_pad = NULL_RTX; |
| rtx_insn *first_no_action_insn = NULL; |
| int call_site = 0; |
| int cur_sec = 0; |
| rtx_insn *section_switch_note = NULL; |
| rtx_insn *first_no_action_insn_before_switch = NULL; |
| rtx_insn *last_no_action_insn_before_switch = NULL; |
| int saved_call_site_base = call_site_base; |
| |
| vec_alloc (crtl->eh.action_record_data, 64); |
| |
| for (iter = get_insns (); iter ; iter = NEXT_INSN (iter)) |
| if (INSN_P (iter)) |
| { |
| eh_landing_pad lp; |
| eh_region region; |
| bool nothrow; |
| int this_action; |
| rtx_code_label *this_landing_pad; |
| |
| insn = iter; |
| if (NONJUMP_INSN_P (insn) |
| && GET_CODE (PATTERN (insn)) == SEQUENCE) |
| insn = XVECEXP (PATTERN (insn), 0, 0); |
| |
| nothrow = get_eh_region_and_lp_from_rtx (insn, ®ion, &lp); |
| if (nothrow) |
| continue; |
| if (region) |
| this_action = collect_one_action_chain (&ar_hash, region); |
| else |
| this_action = -1; |
| |
| /* Existence of catch handlers, or must-not-throw regions |
| implies that an lsda is needed (even if empty). */ |
| if (this_action != -1) |
| crtl->uses_eh_lsda = 1; |
| |
| /* Delay creation of region notes for no-action regions |
| until we're sure that an lsda will be required. */ |
| else if (last_action == -3) |
| { |
| first_no_action_insn = iter; |
| last_action = -1; |
| } |
| |
| if (this_action >= 0) |
| this_landing_pad = lp->landing_pad; |
| else |
| this_landing_pad = NULL; |
| |
| /* Differing actions or landing pads implies a change in call-site |
| info, which implies some EH_REGION note should be emitted. */ |
| if (last_action != this_action |
| || last_landing_pad != this_landing_pad) |
| { |
| /* If there is a queued no-action region in the other section |
| with hot/cold partitioning, emit it now. */ |
| if (first_no_action_insn_before_switch) |
| { |
| gcc_assert (this_action != -1 |
| && last_action == (first_no_action_insn |
| ? -1 : -3)); |
| call_site = add_call_site (NULL_RTX, 0, 0); |
| note = emit_note_before (NOTE_INSN_EH_REGION_BEG, |
| first_no_action_insn_before_switch); |
| NOTE_EH_HANDLER (note) = call_site; |
| note |
| = emit_note_eh_region_end (last_no_action_insn_before_switch); |
| NOTE_EH_HANDLER (note) = call_site; |
| gcc_assert (last_action != -3 |
| || (last_action_insn |
| == last_no_action_insn_before_switch)); |
| first_no_action_insn_before_switch = NULL; |
| last_no_action_insn_before_switch = NULL; |
| call_site_base++; |
| } |
| /* If we'd not seen a previous action (-3) or the previous |
| action was must-not-throw (-2), then we do not need an |
| end note. */ |
| if (last_action >= -1) |
| { |
| /* If we delayed the creation of the begin, do it now. */ |
| if (first_no_action_insn) |
| { |
| call_site = add_call_site (NULL_RTX, 0, cur_sec); |
| note = emit_note_before (NOTE_INSN_EH_REGION_BEG, |
| first_no_action_insn); |
| NOTE_EH_HANDLER (note) = call_site; |
| first_no_action_insn = NULL; |
| } |
| |
| note = emit_note_eh_region_end (last_action_insn); |
| NOTE_EH_HANDLER (note) = call_site; |
| } |
| |
| /* If the new action is must-not-throw, then no region notes |
| are created. */ |
| if (this_action >= -1) |
| { |
| call_site = add_call_site (this_landing_pad, |
| this_action < 0 ? 0 : this_action, |
| cur_sec); |
| note = emit_note_before (NOTE_INSN_EH_REGION_BEG, iter); |
| NOTE_EH_HANDLER (note) = call_site; |
| } |
| |
| last_action = this_action; |
| last_landing_pad = this_landing_pad; |
| } |
| last_action_insn = iter; |
| } |
| else if (NOTE_P (iter) |
| && NOTE_KIND (iter) == NOTE_INSN_SWITCH_TEXT_SECTIONS) |
| { |
| gcc_assert (section_switch_note == NULL_RTX); |
| gcc_assert (flag_reorder_blocks_and_partition); |
| section_switch_note = iter; |
| if (first_no_action_insn) |
| { |
| first_no_action_insn_before_switch = first_no_action_insn; |
| last_no_action_insn_before_switch = last_action_insn; |
| first_no_action_insn = NULL; |
| gcc_assert (last_action == -1); |
| last_action = -3; |
| } |
| /* Force closing of current EH region before section switch and |
| opening a new one afterwards. */ |
| else if (last_action != -3) |
| last_landing_pad = pc_rtx; |
| if (crtl->eh.call_site_record_v[cur_sec]) |
| call_site_base += crtl->eh.call_site_record_v[cur_sec]->length (); |
| cur_sec++; |
| gcc_assert (crtl->eh.call_site_record_v[cur_sec] == NULL); |
| vec_alloc (crtl->eh.call_site_record_v[cur_sec], 10); |
| } |
| |
| if (last_action >= -1 && ! first_no_action_insn) |
| { |
| note = emit_note_eh_region_end (last_action_insn); |
| NOTE_EH_HANDLER (note) = call_site; |
| } |
| |
| call_site_base = saved_call_site_base; |
| |
| return 0; |
| } |
| |
| namespace { |
| |
| const pass_data pass_data_convert_to_eh_region_ranges = |
| { |
| RTL_PASS, /* type */ |
| "eh_ranges", /* name */ |
| OPTGROUP_NONE, /* optinfo_flags */ |
| TV_NONE, /* tv_id */ |
| 0, /* properties_required */ |
| 0, /* properties_provided */ |
| 0, /* properties_destroyed */ |
| 0, /* todo_flags_start */ |
| 0, /* todo_flags_finish */ |
| }; |
| |
| class pass_convert_to_eh_region_ranges : public rtl_opt_pass |
| { |
| public: |
| pass_convert_to_eh_region_ranges (gcc::context *ctxt) |
| : rtl_opt_pass (pass_data_convert_to_eh_region_ranges, ctxt) |
| {} |
| |
| /* opt_pass methods: */ |
| virtual bool gate (function *); |
| virtual unsigned int execute (function *) |
| { |
| int ret = convert_to_eh_region_ranges (); |
| maybe_add_nop_after_section_switch (); |
| return ret; |
| } |
| |
| }; // class pass_convert_to_eh_region_ranges |
| |
| bool |
| pass_convert_to_eh_region_ranges::gate (function *) |
| { |
| /* Nothing to do for SJLJ exceptions or if no regions created. */ |
| if (cfun->eh->region_tree == NULL) |
| return false; |
| if (targetm_common.except_unwind_info (&global_options) == UI_SJLJ) |
| return false; |
| return true; |
| } |
| |
| } // anon namespace |
| |
| rtl_opt_pass * |
| make_pass_convert_to_eh_region_ranges (gcc::context *ctxt) |
| { |
| return new pass_convert_to_eh_region_ranges (ctxt); |
| } |
| |
| static void |
| push_uleb128 (vec<uchar, va_gc> **data_area, unsigned int value) |
| { |
| do |
| { |
| unsigned char byte = value & 0x7f; |
| value >>= 7; |
| if (value) |
| byte |= 0x80; |
| vec_safe_push (*data_area, byte); |
| } |
| while (value); |
| } |
| |
| static void |
| push_sleb128 (vec<uchar, va_gc> **data_area, int value) |
| { |
| unsigned char byte; |
| int more; |
| |
| do |
| { |
| byte = value & 0x7f; |
| value >>= 7; |
| more = ! ((value == 0 && (byte & 0x40) == 0) |
| || (value == -1 && (byte & 0x40) != 0)); |
| if (more) |
| byte |= 0x80; |
| vec_safe_push (*data_area, byte); |
| } |
| while (more); |
| } |
| |
| |
| static int |
| dw2_size_of_call_site_table (int section) |
| { |
| int n = vec_safe_length (crtl->eh.call_site_record_v[section]); |
| int size = n * (4 + 4 + 4); |
| int i; |
| |
| for (i = 0; i < n; ++i) |
| { |
| struct call_site_record_d *cs = |
| (*crtl->eh.call_site_record_v[section])[i]; |
| size += size_of_uleb128 (cs->action); |
| } |
| |
| return size; |
| } |
| |
| static int |
| sjlj_size_of_call_site_table (void) |
| { |
| int n = vec_safe_length (crtl->eh.call_site_record_v[0]); |
| int size = 0; |
| int i; |
| |
| for (i = 0; i < n; ++i) |
| { |
| struct call_site_record_d *cs = |
| (*crtl->eh.call_site_record_v[0])[i]; |
| size += size_of_uleb128 (INTVAL (cs->landing_pad)); |
| size += size_of_uleb128 (cs->action); |
| } |
| |
| return size; |
| } |
| |
| static void |
| dw2_output_call_site_table (int cs_format, int section) |
| { |
| int n = vec_safe_length (crtl->eh.call_site_record_v[section]); |
| int i; |
| const char *begin; |
| |
| if (section == 0) |
| begin = current_function_func_begin_label; |
| else if (first_function_block_is_cold) |
| begin = crtl->subsections.hot_section_label; |
| else |
| begin = crtl->subsections.cold_section_label; |
| |
| for (i = 0; i < n; ++i) |
| { |
| struct call_site_record_d *cs = (*crtl->eh.call_site_record_v[section])[i]; |
| char reg_start_lab[32]; |
| char reg_end_lab[32]; |
| char landing_pad_lab[32]; |
| |
| ASM_GENERATE_INTERNAL_LABEL (reg_start_lab, "LEHB", call_site_base + i); |
| ASM_GENERATE_INTERNAL_LABEL (reg_end_lab, "LEHE", call_site_base + i); |
| |
| if (cs->landing_pad) |
| ASM_GENERATE_INTERNAL_LABEL (landing_pad_lab, "L", |
| CODE_LABEL_NUMBER (cs->landing_pad)); |
| |
| /* ??? Perhaps use insn length scaling if the assembler supports |
| generic arithmetic. */ |
| /* ??? Perhaps use attr_length to choose data1 or data2 instead of |
| data4 if the function is small enough. */ |
| if (cs_format == DW_EH_PE_uleb128) |
| { |
| dw2_asm_output_delta_uleb128 (reg_start_lab, begin, |
| "region %d start", i); |
| dw2_asm_output_delta_uleb128 (reg_end_lab, reg_start_lab, |
| "length"); |
| if (cs->landing_pad) |
| dw2_asm_output_delta_uleb128 (landing_pad_lab, begin, |
| "landing pad"); |
| else |
| dw2_asm_output_data_uleb128 (0, "landing pad"); |
| } |
| else |
| { |
| dw2_asm_output_delta (4, reg_start_lab, begin, |
| "region %d start", i); |
| dw2_asm_output_delta (4, reg_end_lab, reg_start_lab, "length"); |
| if (cs->landing_pad) |
| dw2_asm_output_delta (4, landing_pad_lab, begin, |
| "landing pad"); |
| else |
| dw2_asm_output_data (4, 0, "landing pad"); |
| } |
| dw2_asm_output_data_uleb128 (cs->action, "action"); |
| } |
| |
| call_site_base += n; |
| } |
| |
| static void |
| sjlj_output_call_site_table (void) |
| { |
| int n = vec_safe_length (crtl->eh.call_site_record_v[0]); |
| int i; |
| |
| for (i = 0; i < n; ++i) |
| { |
| struct call_site_record_d *cs = (*crtl->eh.call_site_record_v[0])[i]; |
| |
| dw2_asm_output_data_uleb128 (INTVAL (cs->landing_pad), |
| "region %d landing pad", i); |
| dw2_asm_output_data_uleb128 (cs->action, "action"); |
| } |
| |
| call_site_base += n; |
| } |
| |
| /* Switch to the section that should be used for exception tables. */ |
| |
| static void |
| switch_to_exception_section (const char * ARG_UNUSED (fnname)) |
| { |
| section *s; |
| |
| if (exception_section) |
| s = exception_section; |
| else |
| { |
| int flags; |
| |
| if (EH_TABLES_CAN_BE_READ_ONLY) |
| { |
| int tt_format = |
| ASM_PREFERRED_EH_DATA_FORMAT (/*code=*/0, /*global=*/1); |
| flags = ((! flag_pic |
| || ((tt_format & 0x70) != DW_EH_PE_absptr |
| && (tt_format & 0x70) != DW_EH_PE_aligned)) |
| ? 0 : SECTION_WRITE); |
| } |
| else |
| flags = SECTION_WRITE; |
| |
| /* Compute the section and cache it into exception_section, |
| unless it depends on the function name. */ |
| if (targetm_common.have_named_sections) |
| { |
| #ifdef HAVE_LD_EH_GC_SECTIONS |
| if (flag_function_sections |
| || (DECL_COMDAT_GROUP (current_function_decl) && HAVE_COMDAT_GROUP)) |
| { |
| char *section_name = XNEWVEC (char, strlen (fnname) + 32); |
| /* The EH table must match the code section, so only mark |
| it linkonce if we have COMDAT groups to tie them together. */ |
| if (DECL_COMDAT_GROUP (current_function_decl) && HAVE_COMDAT_GROUP) |
| flags |= SECTION_LINKONCE; |
| sprintf (section_name, ".gcc_except_table.%s", fnname); |
| s = get_section (section_name, flags, current_function_decl); |
| free (section_name); |
| } |
| else |
| #endif |
| exception_section |
| = s = get_section (".gcc_except_table", flags, NULL); |
| } |
| else |
| exception_section |
| = s = flags == SECTION_WRITE ? data_section : readonly_data_section; |
| } |
| |
| switch_to_section (s); |
| } |
| |
| /* Output a reference from an exception table to the type_info object TYPE. |
| TT_FORMAT and TT_FORMAT_SIZE describe the DWARF encoding method used for |
| the value. */ |
| |
| static void |
| output_ttype (tree type, int tt_format, int tt_format_size) |
| { |
| rtx value; |
| bool is_public = true; |
| |
| if (type == NULL_TREE) |
| value = const0_rtx; |
| else |
| { |
| /* FIXME lto. pass_ipa_free_lang_data changes all types to |
| runtime types so TYPE should already be a runtime type |
| reference. When pass_ipa_free_lang data is made a default |
| pass, we can then remove the call to lookup_type_for_runtime |
| below. */ |
| if (TYPE_P (type)) |
| type = lookup_type_for_runtime (type); |
| |
| value = expand_expr (type, NULL_RTX, VOIDmode, EXPAND_INITIALIZER); |
| |
| /* Let cgraph know that the rtti decl is used. Not all of the |
| paths below go through assemble_integer, which would take |
| care of this for us. */ |
| STRIP_NOPS (type); |
| if (TREE_CODE (type) == ADDR_EXPR) |
| { |
| type = TREE_OPERAND (type, 0); |
| if (VAR_P (type)) |
| is_public = TREE_PUBLIC (type); |
| } |
| else |
| gcc_assert (TREE_CODE (type) == INTEGER_CST); |
| } |
| |
| /* Allow the target to override the type table entry format. */ |
| if (targetm.asm_out.ttype (value)) |
| return; |
| |
| if (tt_format == DW_EH_PE_absptr || tt_format == DW_EH_PE_aligned) |
| assemble_integer (value, tt_format_size, |
| tt_format_size * BITS_PER_UNIT, 1); |
| else |
| dw2_asm_output_encoded_addr_rtx (tt_format, value, is_public, NULL); |
| } |
| |
| /* Output an exception table for the current function according to SECTION. |
| |
| If the function has been partitioned into hot and cold parts, value 0 for |
| SECTION refers to the table associated with the hot part while value 1 |
| refers to the table associated with the cold part. If the function has |
| not been partitioned, value 0 refers to the single exception table. */ |
| |
| static void |
| output_one_function_exception_table (int section) |
| { |
| int tt_format, cs_format, lp_format, i; |
| char ttype_label[32]; |
| char cs_after_size_label[32]; |
| char cs_end_label[32]; |
| int call_site_len; |
| int have_tt_data; |
| int tt_format_size = 0; |
| |
| have_tt_data = (vec_safe_length (cfun->eh->ttype_data) |
| || (targetm.arm_eabi_unwinder |
| ? vec_safe_length (cfun->eh->ehspec_data.arm_eabi) |
| : vec_safe_length (cfun->eh->ehspec_data.other))); |
| |
| /* Indicate the format of the @TType entries. */ |
| if (! have_tt_data) |
| tt_format = DW_EH_PE_omit; |
| else |
| { |
| tt_format = ASM_PREFERRED_EH_DATA_FORMAT (/*code=*/0, /*global=*/1); |
| if (HAVE_AS_LEB128) |
| ASM_GENERATE_INTERNAL_LABEL (ttype_label, |
| section ? "LLSDATTC" : "LLSDATT", |
| current_function_funcdef_no); |
| |
| tt_format_size = size_of_encoded_value (tt_format); |
| |
| assemble_align (tt_format_size * BITS_PER_UNIT); |
| } |
| |
| targetm.asm_out.internal_label (asm_out_file, section ? "LLSDAC" : "LLSDA", |
| current_function_funcdef_no); |
| |
| /* The LSDA header. */ |
| |
| /* Indicate the format of the landing pad start pointer. An omitted |
| field implies @LPStart == @Start. */ |
| /* Currently we always put @LPStart == @Start. This field would |
| be most useful in moving the landing pads completely out of |
| line to another section, but it could also be used to minimize |
| the size of uleb128 landing pad offsets. */ |
| lp_format = DW_EH_PE_omit; |
| dw2_asm_output_data (1, lp_format, "@LPStart format (%s)", |
| eh_data_format_name (lp_format)); |
| |
| /* @LPStart pointer would go here. */ |
| |
| dw2_asm_output_data (1, tt_format, "@TType format (%s)", |
| eh_data_format_name (tt_format)); |
| |
| if (!HAVE_AS_LEB128) |
| { |
| if (targetm_common.except_unwind_info (&global_options) == UI_SJLJ) |
| call_site_len = sjlj_size_of_call_site_table (); |
| else |
| call_site_len = dw2_size_of_call_site_table (section); |
| } |
| |
| /* A pc-relative 4-byte displacement to the @TType data. */ |
| if (have_tt_data) |
| { |
| if (HAVE_AS_LEB128) |
| { |
| char ttype_after_disp_label[32]; |
| ASM_GENERATE_INTERNAL_LABEL (ttype_after_disp_label, |
| section ? "LLSDATTDC" : "LLSDATTD", |
| current_function_funcdef_no); |
| dw2_asm_output_delta_uleb128 (ttype_label, ttype_after_disp_label, |
| "@TType base offset"); |
| ASM_OUTPUT_LABEL (asm_out_file, ttype_after_disp_label); |
| } |
| else |
| { |
| /* Ug. Alignment queers things. */ |
| unsigned int before_disp, after_disp, last_disp, disp; |
| |
| before_disp = 1 + 1; |
| after_disp = (1 + size_of_uleb128 (call_site_len) |
| + call_site_len |
| + vec_safe_length (crtl->eh.action_record_data) |
| + (vec_safe_length (cfun->eh->ttype_data) |
| * tt_format_size)); |
| |
| disp = after_disp; |
| do |
| { |
| unsigned int disp_size, pad; |
| |
| last_disp = disp; |
| disp_size = size_of_uleb128 (disp); |
| pad = before_disp + disp_size + after_disp; |
| if (pad % tt_format_size) |
| pad = tt_format_size - (pad % tt_format_size); |
| else |
| pad = 0; |
| disp = after_disp + pad; |
| } |
| while (disp != last_disp); |
| |
| dw2_asm_output_data_uleb128 (disp, "@TType base offset"); |
| } |
| } |
| |
| /* Indicate the format of the call-site offsets. */ |
| if (HAVE_AS_LEB128) |
| cs_format = DW_EH_PE_uleb128; |
| else |
| cs_format = DW_EH_PE_udata4; |
| |
| dw2_asm_output_data (1, cs_format, "call-site format (%s)", |
| eh_data_format_name (cs_format)); |
| |
| if (HAVE_AS_LEB128) |
| { |
| ASM_GENERATE_INTERNAL_LABEL (cs_after_size_label, |
| section ? "LLSDACSBC" : "LLSDACSB", |
| current_function_funcdef_no); |
| ASM_GENERATE_INTERNAL_LABEL (cs_end_label, |
| section ? "LLSDACSEC" : "LLSDACSE", |
| current_function_funcdef_no); |
| dw2_asm_output_delta_uleb128 (cs_end_label, cs_after_size_label, |
| "Call-site table length"); |
| ASM_OUTPUT_LABEL (asm_out_file, cs_after_size_label); |
| if (targetm_common.except_unwind_info (&global_options) == UI_SJLJ) |
| sjlj_output_call_site_table (); |
| else |
| dw2_output_call_site_table (cs_format, section); |
| ASM_OUTPUT_LABEL (asm_out_file, cs_end_label); |
| } |
| else |
| { |
| dw2_asm_output_data_uleb128 (call_site_len, "Call-site table length"); |
| if (targetm_common.except_unwind_info (&global_options) == UI_SJLJ) |
| sjlj_output_call_site_table (); |
| else |
| dw2_output_call_site_table (cs_format, section); |
| } |
| |
| /* ??? Decode and interpret the data for flag_debug_asm. */ |
| { |
| uchar uc; |
| FOR_EACH_VEC_ELT (*crtl->eh.action_record_data, i, uc) |
| dw2_asm_output_data (1, uc, i ? NULL : "Action record table"); |
| } |
| |
| if (have_tt_data) |
| assemble_align (tt_format_size * BITS_PER_UNIT); |
| |
| i = vec_safe_length (cfun->eh->ttype_data); |
| while (i-- > 0) |
| { |
| tree type = (*cfun->eh->ttype_data)[i]; |
| output_ttype (type, tt_format, tt_format_size); |
| } |
| |
| if (HAVE_AS_LEB128 && have_tt_data) |
| ASM_OUTPUT_LABEL (asm_out_file, ttype_label); |
| |
| /* ??? Decode and interpret the data for flag_debug_asm. */ |
| if (targetm.arm_eabi_unwinder) |
| { |
| tree type; |
| for (i = 0; |
| vec_safe_iterate (cfun->eh->ehspec_data.arm_eabi, i, &type); ++i) |
| output_ttype (type, tt_format, tt_format_size); |
| } |
| else |
| { |
| uchar uc; |
| for (i = 0; |
| vec_safe_iterate (cfun->eh->ehspec_data.other, i, &uc); ++i) |
| dw2_asm_output_data (1, uc, |
| i ? NULL : "Exception specification table"); |
| } |
| } |
| |
| /* Output an exception table for the current function according to SECTION, |
| switching back and forth from the function section appropriately. |
| |
| If the function has been partitioned into hot and cold parts, value 0 for |
| SECTION refers to the table associated with the hot part while value 1 |
| refers to the table associated with the cold part. If the function has |
| not been partitioned, value 0 refers to the single exception table. */ |
| |
| void |
| output_function_exception_table (int section) |
| { |
| const char *fnname = get_fnname_from_decl (current_function_decl); |
| rtx personality = get_personality_function (current_function_decl); |
| |
| /* Not all functions need anything. */ |
| if (!crtl->uses_eh_lsda |
| || targetm_common.except_unwind_info (&global_options) == UI_NONE) |
| return; |
| |
| /* No need to emit any boilerplate stuff for the cold part. */ |
| if (section == 1 && !crtl->eh.call_site_record_v[1]) |
| return; |
| |
| if (personality) |
| { |
| assemble_external_libcall (personality); |
| |
| if (targetm.asm_out.emit_except_personality) |
| targetm.asm_out.emit_except_personality (personality); |
| } |
| |
| switch_to_exception_section (fnname); |
| |
| /* If the target wants a label to begin the table, emit it here. */ |
| targetm.asm_out.emit_except_table_label (asm_out_file); |
| |
| /* Do the real work. */ |
| output_one_function_exception_table (section); |
| |
| switch_to_section (current_function_section ()); |
| } |
| |
| void |
| set_eh_throw_stmt_table (function *fun, hash_map<gimple *, int> *table) |
| { |
| fun->eh->throw_stmt_table = table; |
| } |
| |
| hash_map<gimple *, int> * |
| get_eh_throw_stmt_table (struct function *fun) |
| { |
| return fun->eh->throw_stmt_table; |
| } |
| |
| /* Determine if the function needs an EH personality function. */ |
| |
| enum eh_personality_kind |
| function_needs_eh_personality (struct function *fn) |
| { |
| enum eh_personality_kind kind = eh_personality_none; |
| eh_region i; |
| |
| FOR_ALL_EH_REGION_FN (i, fn) |
| { |
| switch (i->type) |
| { |
| case ERT_CLEANUP: |
| /* Can do with any personality including the generic C one. */ |
| kind = eh_personality_any; |
| break; |
| |
| case ERT_TRY: |
| case ERT_ALLOWED_EXCEPTIONS: |
| /* Always needs a EH personality function. The generic C |
| personality doesn't handle these even for empty type lists. */ |
| return eh_personality_lang; |
| |
| case ERT_MUST_NOT_THROW: |
| /* Always needs a EH personality function. The language may specify |
| what abort routine that must be used, e.g. std::terminate. */ |
| return eh_personality_lang; |
| } |
| } |
| |
| return kind; |
| } |
| |
| /* Dump EH information to OUT. */ |
| |
| void |
| dump_eh_tree (FILE * out, struct function *fun) |
| { |
| eh_region i; |
| int depth = 0; |
| static const char *const type_name[] = { |
| "cleanup", "try", "allowed_exceptions", "must_not_throw" |
| }; |
| |
| i = fun->eh->region_tree; |
| if (!i) |
| return; |
| |
| fprintf (out, "Eh tree:\n"); |
| |