/* * This file is part of libFirm. * Copyright (C) 2012 University of Karlsruhe. */ /** * @file * @brief Memory disambiguator * @author Michael Beck * @date 27.12.2006 */ #include "irmemory_t.h" #include "adt/pmap.h" #include "debug.h" #include "hashptr.h" #include "irflag.h" #include "irflag.h" #include "irgraph_t.h" #include "irgwalk.h" #include "irnode_t.h" #include "irouts_t.h" #include "irprintf.h" #include "irprog_t.h" #include "panic.h" #include "type_t.h" #include "typerep.h" #include "util.h" #include #include /** The debug handle. */ DEBUG_ONLY(static firm_dbg_module_t *dbg = NULL;) DEBUG_ONLY(static firm_dbg_module_t *dbgcall = NULL;) /** The global memory disambiguator options. */ static unsigned global_mem_disamgig_opt = aa_opt_none; const char *get_ir_alias_relation_name(ir_alias_relation rel) { #define X(a) case a: return #a switch (rel) { X(ir_no_alias); X(ir_may_alias); X(ir_sure_alias); } #undef X panic("unknown alias relation"); } ir_disambiguator_options get_irg_memory_disambiguator_options( ir_graph const *const irg) { unsigned opt = irg->mem_disambig_opt; if (opt & aa_opt_inherited) return global_mem_disamgig_opt; return opt; } void set_irg_memory_disambiguator_options(ir_graph *irg, ir_disambiguator_options options) { irg->mem_disambig_opt = options & ~aa_opt_inherited; } void set_irp_memory_disambiguator_options(ir_disambiguator_options options) { global_mem_disamgig_opt = options; } ir_storage_class_class_t get_base_sc(ir_storage_class_class_t x) { return x & ~ir_sc_modifiers; } /** * Find the base address and entity of an Sel/Member node. * * @param node the node * @param pEnt after return points to the base entity. * * @return the base address. */ static const ir_node *find_base_addr(const ir_node *node, ir_entity **pEnt) { const ir_node *member = NULL; for (;;) { if (is_Sel(node)) { node = get_Sel_ptr(node); continue; } else if (is_Member(node)) { ir_node *pred = get_Member_ptr(node); /** local variables are members of the frame type, but all disjunct * so we regard them as base addresses */ if (is_Proj(pred) && pred == get_irg_frame(get_irn_irg(pred))) break; member = node; node = pred; } else { break; } } if (member != NULL) *pEnt = get_Member_entity(member); return node; } /** * Returns true if @c compound is a compound type that contains a * member with type @c member, including recursively, or if @c * compound is an array type with a base type equal to or containing * @c member. * * @param compound The compound type * @param member The member type * * @return true, if @c compound contains @c member */ static bool type_contains(const ir_type *compound, const ir_type *member) { if (is_Array_type(compound)) { ir_type *elem = get_array_element_type(compound); return elem == member || type_contains(elem, member); } else if (is_compound_type(compound)) { size_t n = get_compound_n_members(compound); for (size_t pos = 0; pos < n; pos++) { ir_entity *ent = get_compound_member(compound, pos); ir_type *pos_type = get_entity_type(ent); if (pos_type == member || type_contains(pos_type, member)) { return true; } } return false; } else { return false; } } /** * Determine the alias relation by checking if type1 and type2 are * different types. * * @param addr1 The first type. * @param addr2 The second type. */ static ir_alias_relation different_types(const ir_type *type1, const ir_type *type2) { if (type1 == type2) { return ir_may_alias; } /* do deref until no pointer types are found */ while (is_Pointer_type(type1) && is_Pointer_type(type2)) { type1 = get_pointer_points_to_type(type1); type2 = get_pointer_points_to_type(type2); } if (type_contains(type1, type2) || type_contains(type2, type1)) { return ir_may_alias; } if (is_Class_type(type1) && is_Class_type(type2) && (is_SubClass_of(type1, type2) || is_SubClass_of(type2, type1))) { return ir_may_alias; } return ir_no_alias; } /** * Returns non-zero if a node is a result on a malloc-like routine. * * @param node the Proj node to test */ static bool is_malloc_Result(const ir_node *node) { node = get_Proj_pred(node); if (!is_Proj(node)) return false; node = get_Proj_pred(node); if (!is_Call(node)) return false; ir_entity *callee = get_Call_callee(node); return callee != NULL && (get_entity_additional_properties(callee) & mtp_property_malloc); } ir_storage_class_class_t classify_pointer(const ir_node *const addr, const ir_node *const base) { /* part1: determine class */ ir_storage_class_class_t res; ir_entity *entity; if (is_Address(base)) { entity = get_Address_entity(base); ir_type *owner = get_entity_owner(entity); res = owner == get_tls_type() ? ir_sc_tls : ir_sc_globalvar; goto analyze_entity; } else if (is_Member(base)) { /* should only happen for local vars */ assert(get_Member_ptr(base) == get_irg_frame(get_irn_irg(base))); entity = get_Member_entity(base); res = is_parameter_entity(entity) ? ir_sc_argument : ir_sc_localvar; goto analyze_entity; } else if (is_Proj(base)) { if (is_malloc_Result(base)) res = ir_sc_malloced; else res = ir_sc_pointer; } else if (is_Const(base)) { ir_tarval *tv = get_Const_tarval(base); if (tarval_is_null(tv)) res = ir_sc_null; else res = ir_sc_globaladdr; } else { /* we always should have Member(irg_frame) as base address */ assert(base != get_irg_frame(get_irn_irg(base))); res = ir_sc_pointer; } /* part2: modifiers */ /* if we select a member/array elem from addr, then it must have been * a compound type */ if (is_Sel(addr) || is_Member(addr)) res |= ir_sc_modifier_obj_comp; return res; analyze_entity: if (!(get_entity_usage(entity) & ir_usage_address_taken)) res |= ir_sc_modifier_nottaken; const ir_type *type = get_entity_type(entity); res |= is_compound_type(type) ? ir_sc_modifier_obj_comp : ir_sc_modifier_obj_prim; return res; } typedef struct address_info { ir_node const *base; ir_node const *sym_offset; long offset; bool has_const_offset; } address_info; static address_info get_address_info(ir_node const *addr) { ir_node *sym_offset = NULL; long offset = 0; bool has_const_offset = true; for (;;) { switch (get_irn_opcode(addr)) { case iro_Add: { ir_node *ptr_node; ir_node *int_node; ir_mode *const mode_left = get_irn_mode(get_Add_left(addr)); if (mode_is_reference(mode_left)) { ptr_node = get_Add_left(addr); int_node = get_Add_right(addr); } else { ptr_node = get_Add_right(addr); int_node = get_Add_left(addr); } if (is_Const(int_node)) { ir_tarval *tv = get_Const_tarval(int_node); if (tarval_is_long(tv)) { /* TODO: check for overflow */ offset += get_tarval_long(tv); goto follow_ptr; } } if (!sym_offset) { sym_offset = int_node; } else { // addr has more than one symbolic offset, give up. has_const_offset = false; } follow_ptr: addr = ptr_node; break; } case iro_Sub: has_const_offset = false; addr = get_Sub_left(addr); break; default: return (address_info){ addr, sym_offset, offset, has_const_offset }; } } } static ir_alias_relation _get_alias_relation(const ir_node *addr1, const ir_type *const objt1, unsigned size1, const ir_node *addr2, const ir_type *const objt2, unsigned size2) { if (addr1 == addr2) return ir_sure_alias; ir_graph *const irg = get_irn_irg(addr1); unsigned const options = get_irg_memory_disambiguator_options(irg); if (options & aa_opt_always_alias) return ir_may_alias; /* The Armageddon switch */ if (options & aa_opt_no_alias) return ir_no_alias; /* do the addresses have constants offsets from the same base? * Note: sub X, C is normalized to add X, -C */ /* * Currently, only expressions with at most one symbolic * offset can be handled. To extend this, change * sym_offset to be a set, and compare the sets. */ address_info const info1 = get_address_info(addr1); address_info const info2 = get_address_info(addr2); long offset1 = info1.offset; long offset2 = info2.offset; addr1 = info1.base; addr2 = info2.base; /* same base address -> compare offsets if possible. * FIXME: type long is not sufficient for this task ... */ if (addr1 == addr2 && info1.sym_offset == info2.sym_offset && info1.has_const_offset && info2.has_const_offset) { unsigned long first_offset; unsigned long last_offset; unsigned first_size; if (offset1 <= offset2) { first_offset = offset1; last_offset = offset2; first_size = size1; } else { first_offset = offset2; last_offset = offset1; first_size = size2; } return first_offset + first_size <= last_offset ? ir_no_alias : ir_sure_alias; } /* skip Sels/Members */ ir_entity *ent1 = NULL; ir_entity *ent2 = NULL; const ir_node *base1 = find_base_addr(addr1, &ent1); const ir_node *base2 = find_base_addr(addr2, &ent2); /* two struct accesses -> compare entities */ if (ent1 != NULL && ent2 != NULL) { if (ent1 == ent2) { if (base1 == base2) return ir_sure_alias; goto check_classes; } ir_type *owner1 = get_entity_owner(ent1); ir_type *owner2 = get_entity_owner(ent2); if (owner1 != owner2) { /* TODO: We have to differentiate 3 cases: * - owner1 or owner2 is a type used in a subtree of the other. * - If there exists a union type where the first elements towards * owner1+owner2 and the fields inside owner1+owner2 are * compatible, then they may alias. * - All other cases cannot alias. * => for now we assume may alias */ goto check_classes; } /* same owner, different entities? They may only alias if we have a * union or if one of them is a bitfield members. */ /* TODO: can we test if the base units actually overlap in the bitfield * case? */ if (!is_Union_type(owner1) && get_entity_bitfield_size(ent1) == 0 && get_entity_bitfield_size(ent2) == 0) return ir_no_alias; } check_classes:; /* no alias if 1 is a primitive object and the other a compound object */ const ir_storage_class_class_t mod1 = classify_pointer(addr1, base1); const ir_storage_class_class_t mod2 = classify_pointer(addr2, base2); if (((mod1 | mod2) & (ir_sc_modifier_obj_comp | ir_sc_modifier_obj_prim)) == (ir_sc_modifier_obj_comp | ir_sc_modifier_obj_prim)) return ir_no_alias; const ir_storage_class_class_t class1 = mod1 & ~ir_sc_modifiers; const ir_storage_class_class_t class2 = mod2 & ~ir_sc_modifiers; ir_storage_class_class_t other_class; ir_storage_class_class_t other_mod; if (class1 == ir_sc_pointer) { other_class = class2; other_mod = mod2; goto pointer; } else if (class2 == ir_sc_pointer) { other_class = class1; other_mod = mod1; pointer: /* a pointer and an object whose address was never taken */ if (other_mod & ir_sc_modifier_nottaken) return ir_no_alias; /* the null pointer aliases nothing */ if (other_class == ir_sc_null) return ir_no_alias; } else if (class1 != class2) { /* objects from different memory spaces cannot alias */ return ir_no_alias; } else { /* both classes are equal */ if (class1 == ir_sc_globalvar) { ir_entity *entity1 = get_Address_entity(base1); ir_entity *entity2 = get_Address_entity(base2); return entity1 != entity2 ? ir_no_alias : ir_may_alias; } else if (class1 == ir_sc_localvar) { ir_entity *entity1 = get_Member_entity(base1); ir_entity *entity2 = get_Member_entity(base2); return entity1 != entity2 ? ir_no_alias : ir_may_alias; } else if (class1 == ir_sc_globaladdr) { offset1 += get_Const_long(base1); offset2 += get_Const_long(base2); unsigned type_size = MAX(size1, size2); if ((unsigned long)labs(offset2 - offset1) >= type_size) return ir_no_alias; else return ir_sure_alias; } else if (class1 == ir_sc_malloced) { return base1 == base2 ? ir_sure_alias : ir_no_alias; } } /* Type based alias analysis */ if (options & aa_opt_type_based) { ir_alias_relation rel; if (options & aa_opt_byte_type_may_alias) { if (get_type_size(objt1) == 1 || get_type_size(objt2) == 1) { /* One of the types address a byte. Assume a ir_may_alias and leave the type based check. */ goto leave_type_based_alias; } } /* cheap check: If the type sizes did not match, the types MUST be different */ /* No, one might be part of the other. */ /* if (get_type_size(objt1) != get_type_size(objt2)) */ /* return ir_no_alias; */ /* cheap test: if only one is a reference type, no alias */ if (is_Pointer_type(objt1) != is_Pointer_type(objt2)) { return ir_no_alias; } if (is_Primitive_type(objt1) && is_Primitive_type(objt2)) { const ir_mode *const mode1 = get_type_mode(objt1); const ir_mode *const mode2 = get_type_mode(objt2); /* cheap test: if arithmetic is different, no alias */ if (get_mode_arithmetic(mode1) != get_mode_arithmetic(mode2)) return ir_no_alias; /* no alias if 1 is a reference and the other isn't */ if (mode_is_reference(mode1) != mode_is_reference(mode2)) return ir_no_alias; } rel = different_types(objt1, objt2); if (rel != ir_may_alias) return rel; leave_type_based_alias:; } return ir_may_alias; } ir_alias_relation get_alias_relation(const ir_node *const addr1, const ir_type *const type1, unsigned size1, const ir_node *const addr2, const ir_type *const type2, unsigned size2) { ir_alias_relation rel = _get_alias_relation(addr1, type1, size1, addr2, type2, size2); DB((dbg, LEVEL_1, "alias(%+F, %+F) = %s\n", addr1, addr2, get_ir_alias_relation_name(rel))); return rel; } /** * Check the mode of a Load/Store with the mode of the entity * that is accessed. * If the mode of the entity and the Load/Store mode do not match, we * have the bad reinterpret case: * * int i; * char b = *(char *)&i; * * We do NOT count this as one value and return address_taken * in that case. * However, we support an often used case. If the mode is two-complement * we allow casts between signed/unsigned. * * @param mode the mode of the Load/Store * @param ent_mode the mode of the accessed entity * * @return non-zero if the Load/Store is a hidden cast, zero else */ static bool is_hidden_cast(const ir_mode *mode, const ir_mode *ent_mode) { if (ent_mode == NULL) return false; if (ent_mode != mode && (get_mode_size_bits(ent_mode) != get_mode_size_bits(mode) || get_mode_arithmetic(ent_mode) != irma_twos_complement || get_mode_arithmetic(mode) != irma_twos_complement)) { return true; } return false; } /** * Determine the usage state of a node (or its successor Sels). * * @param irn the node */ static ir_entity_usage determine_entity_usage(const ir_node *irn, const ir_entity *entity) { unsigned res = 0; for (int i = get_irn_n_outs(irn); i-- > 0; ) { int succ_pos; const ir_node *succ = get_irn_out_ex(irn, i, &succ_pos); switch (get_irn_opcode(succ)) { case iro_Load: /* beware: irn might be a Id node here, so irn might be not equal to get_Load_ptr(succ) */ res |= ir_usage_read; /* check if this load is not a hidden conversion */ ir_mode *mode = get_Load_mode(succ); ir_mode *emode = get_type_mode(get_entity_type(entity)); if (is_hidden_cast(mode, emode)) res |= ir_usage_reinterpret_cast; break; case iro_Store: /* check that the node is not the Store's value */ if (succ_pos == n_Store_value) { res |= ir_usage_unknown; } else if (succ_pos == n_Store_ptr) { res |= ir_usage_write; /* check if this Store is not a hidden conversion */ ir_node *value = get_Store_value(succ); ir_mode *mode = get_irn_mode(value); ir_mode *emode = get_type_mode(get_entity_type(entity)); if (is_hidden_cast(mode, emode)) res |= ir_usage_reinterpret_cast; } assert(irn != get_Store_mem(succ)); break; case iro_CopyB: { /* CopyB are like Loads/Stores */ ir_type *tp = get_entity_type(entity); if (tp != get_CopyB_type(succ)) { /* bad, different types, might be a hidden conversion */ res |= ir_usage_reinterpret_cast; } if (succ_pos == n_CopyB_dst) { res |= ir_usage_write; } else { assert(succ_pos == n_CopyB_src); res |= ir_usage_read; } break; } case iro_Sel: case iro_Add: case iro_Sub: case iro_Id: /* Check the successor of irn. */ res |= determine_entity_usage(succ, entity); break; case iro_Member: { ir_entity *member_entity = get_Member_entity(succ); /* Check the successor of irn. */ res |= determine_entity_usage(succ, member_entity); break; } case iro_Call: if (succ_pos == n_Call_ptr) { /* TODO: we could check for reinterpret casts here... * But I doubt anyone is interested in that bit for * function entities and I'm too lazy to write the code now. */ res |= ir_usage_read; } else { assert(succ_pos != n_Call_mem); int arg_nr = succ_pos - n_Call_max - 1; ir_type *type = get_Call_type(succ); ir_type *arg_type = get_method_param_type(type, arg_nr); if (is_aggregate_type(arg_type)) res |= ir_usage_read; else res |= ir_usage_unknown; } break; case iro_Builtin: { ir_builtin_kind kind = get_Builtin_kind(succ); /* the parameters of the may_alias builtin do not lead to * read/write or address taken. */ if (kind == ir_bk_may_alias) break; res |= ir_usage_unknown; break; } default: /* another op, we don't know anything (we could do more advanced * things like a dataflow analysis here) */ res |= ir_usage_unknown; break; } } return (ir_entity_usage) res; } /** * Update the usage flags of all frame entities. */ static void analyse_irg_entity_usage(ir_graph *irg) { assure_irg_properties(irg, IR_GRAPH_PROPERTY_CONSISTENT_OUTS); /* set initial state to not_taken, as this is the "smallest" state */ ir_type *frame_type = get_irg_frame_type(irg); for (size_t i = 0, n = get_compound_n_members(frame_type); i < n; ++i) { ir_entity *ent = get_compound_member(frame_type, i); /* methods can only be analyzed globally */ if (is_method_entity(ent)) continue; ir_entity_usage flags = ir_usage_none; if (get_entity_linkage(ent) & IR_LINKAGE_HIDDEN_USER) flags = ir_usage_unknown; set_entity_usage(ent, flags); } ir_node *irg_frame = get_irg_frame(irg); foreach_irn_out_r(irg_frame, j, succ) { if (!is_Member(succ)) continue; ir_entity *entity = get_Member_entity(succ); unsigned flags = get_entity_usage(entity); flags |= determine_entity_usage(succ, entity); set_entity_usage(entity, (ir_entity_usage) flags); } /* now computed */ add_irg_properties(irg, IR_GRAPH_PROPERTY_CONSISTENT_ENTITY_USAGE); } void assure_irg_entity_usage_computed(ir_graph *irg) { if (irg_has_properties(irg, IR_GRAPH_PROPERTY_CONSISTENT_ENTITY_USAGE)) return; analyse_irg_entity_usage(irg); } /** * Initialize the entity_usage flag for a global type like type. */ static void init_entity_usage(ir_type *tp) { /* We have to be conservative: All external visible entities are unknown */ for (size_t i = 0, n = get_compound_n_members(tp); i < n; ++i) { ir_entity *ent = get_compound_member(tp, i); unsigned flags = ir_usage_none; if (entity_is_externally_visible(ent)) { flags |= ir_usage_unknown; } set_entity_usage(ent, (ir_entity_usage) flags); } } /** * Mark all entities used in the initializer's value as unknown usage. * * @param value the value to check */ static void check_initializer_value(ir_node *value) { /* Handle each node at most once. */ if (irn_visited_else_mark(value)) return; /* let's check if it's an address */ if (is_Address(value)) { ir_entity *ent = get_Address_entity(value); set_entity_usage(ent, ir_usage_unknown); } foreach_irn_in(value, i, op) { check_initializer_value(op); } } /** * Mark all entities used in the initializer as unknown usage. * * @param initializer the initializer to check */ static void check_initializer_nodes(ir_initializer_t *initializer) { switch (initializer->kind) { case IR_INITIALIZER_CONST: { ir_node *n = initializer->consti.value; ir_graph *irg = get_irn_irg(n); ir_reserve_resources(irg, IR_RESOURCE_IRN_VISITED); inc_irg_visited(irg); check_initializer_value(n); ir_free_resources(irg, IR_RESOURCE_IRN_VISITED); return; } case IR_INITIALIZER_TARVAL: case IR_INITIALIZER_NULL: return; case IR_INITIALIZER_COMPOUND: for (size_t i = 0; i < initializer->compound.n_initializers; ++i) { ir_initializer_t *sub_initializer = initializer->compound.initializers[i]; check_initializer_nodes(sub_initializer); } return; } panic("invalid initializer found"); } /** * Mark all entities used in the initializer for the given entity as unknown * usage. * * @param ent the entity */ static void check_initializer(ir_entity *ent) { if (get_entity_kind(ent) == IR_ENTITY_NORMAL) { ir_initializer_t *const init = get_entity_initializer(ent); if (init != NULL) check_initializer_nodes(init); } } /** * Mark all entities used in initializers as unknown usage. * * @param tp a compound type */ static void check_initializers(ir_type *tp) { for (size_t i = 0, n = get_compound_n_members(tp); i < n; ++i) { ir_entity *ent = get_compound_member(tp, i); check_initializer(ent); } } #ifdef DEBUG_libfirm /** * Print the entity usage flags of all entities of a given type for debugging. * * @param tp a compound type */ static void print_entity_usage_flags(const ir_type *tp) { for (size_t i = 0, n = get_compound_n_members(tp); i < n; ++i) { ir_entity *ent = get_compound_member(tp, i); ir_entity_usage flags = get_entity_usage(ent); if (flags == 0) continue; ir_printf("%+F:", ent); if (flags & ir_usage_address_taken) printf(" address_taken"); if (flags & ir_usage_read) printf(" read"); if (flags & ir_usage_write) printf(" write"); if (flags & ir_usage_reinterpret_cast) printf(" reinterp_cast"); printf("\n"); } } #endif /* DEBUG_libfirm */ /** * Post-walker: check for global entity address */ static void check_global_address(ir_node *irn, void *data) { (void)data; if (!is_Address(irn)) return; ir_entity *entity = get_Address_entity(irn); unsigned flags = get_entity_usage(entity); flags |= determine_entity_usage(irn, entity); set_entity_usage(entity, (ir_entity_usage) flags); } /** * Update the entity usage flags of all global entities. */ static void analyse_irp_globals_entity_usage(void) { for (ir_segment_t s = IR_SEGMENT_FIRST; s <= IR_SEGMENT_LAST; ++s) { ir_type *type = get_segment_type(s); init_entity_usage(type); } for (ir_segment_t s = IR_SEGMENT_FIRST; s <= IR_SEGMENT_LAST; ++s) { ir_type *type = get_segment_type(s); check_initializers(type); } foreach_irp_irg(i, irg) { assure_irg_properties(irg, IR_GRAPH_PROPERTY_CONSISTENT_OUTS | IR_GRAPH_PROPERTY_NO_TUPLES); irg_walk_graph(irg, NULL, check_global_address, NULL); } #ifdef DEBUG_libfirm if (firm_dbg_get_mask(dbg) & LEVEL_1) { for (ir_segment_t s = IR_SEGMENT_FIRST; s <= IR_SEGMENT_LAST; ++s) { print_entity_usage_flags(get_segment_type(s)); } } #endif /* DEBUG_libfirm */ /* now computed */ irp->globals_entity_usage_state = ir_entity_usage_computed; } ir_entity_usage_computed_state get_irp_globals_entity_usage_state(void) { return irp->globals_entity_usage_state; } void set_irp_globals_entity_usage_state(ir_entity_usage_computed_state state) { irp->globals_entity_usage_state = state; } void assure_irp_globals_entity_usage_computed(void) { if (irp->globals_entity_usage_state != ir_entity_usage_not_computed) return; analyse_irp_globals_entity_usage(); } void firm_init_memory_disambiguator(void) { FIRM_DBG_REGISTER(dbg, "firm.ana.irmemory"); FIRM_DBG_REGISTER(dbgcall, "firm.opt.cc"); } /** Maps method types to cloned method types. */ static pmap *mtp_map; /** * Clone a method type if not already cloned. * * @param tp the type to clone */ static ir_type *clone_type_and_cache(ir_type *const tp, int const variadic_index) { ir_type *res = pmap_get(ir_type, mtp_map, tp); if (res == NULL) { mtp_additional_properties const props = get_method_additional_properties(tp); res = clone_type_method(tp, variadic_index, props | mtp_property_private); pmap_insert(mtp_map, tp, res); } return res; } /** * Walker: clone all call types of Calls to methods having the * mtp_property_private property set. */ static void update_calls_to_private(ir_node *call, void *env) { (void)env; if (!is_Call(call)) return; ir_entity *callee = get_Call_callee(call); if (callee == NULL) return; ir_type *ctp = get_Call_type(call); if ((get_entity_additional_properties(callee) & mtp_property_private) && ((get_method_additional_properties(ctp) & mtp_property_private) == 0)) { ir_type *const entity_ctp = get_entity_type(callee); /* clear mismatches in variadicity that can happen in obscure C * programs and break when changing to private calling convention. */ ctp = clone_type_and_cache(ctp, get_method_variadic_index(entity_ctp)); set_Call_type(call, ctp); DB((dbgcall, LEVEL_1, "changed call to private method %+F using cloned type %+F\n", callee, ctp)); } } void mark_private_methods(void) { assure_irp_globals_entity_usage_computed(); mtp_map = pmap_create(); /* first step: change the calling conventions of the local non-escaped entities */ bool changed = false; foreach_irp_irg(i, irg) { ir_entity *ent = get_irg_entity(irg); ir_entity_usage flags = get_entity_usage(ent); if (!(flags & ir_usage_address_taken) && !entity_is_externally_visible(ent)) { ir_type *mtp = get_entity_type(ent); add_entity_additional_properties(ent, mtp_property_private); DB((dbgcall, LEVEL_1, "found private method %+F\n", ent)); if ((get_method_additional_properties(mtp) & mtp_property_private) == 0) { /* need a new type */ mtp = clone_type_and_cache(mtp, get_method_variadic_index(mtp)); set_entity_type(ent, mtp); DB((dbgcall, LEVEL_2, "changed entity type of %+F to %+F\n", ent, mtp)); changed = true; } } } if (changed) all_irg_walk(NULL, update_calls_to_private, NULL); pmap_destroy(mtp_map); } /** * Find the entity that the given pointer points to. * * This function returns the entity into which @c ptr points, ignoring * any offsets (it assumes that offsets always stay within the * entity). * * This function does *not* always return a top-level entity * (i.e. local/global variable), but may also return a member of * another entity. * * If no entity can be found (e.g. pointer is itself result of a * Load), NULL is returned. */ static ir_entity *find_entity(ir_node *ptr) { switch (get_irn_opcode(ptr)) { case iro_Address: return get_Address_entity(ptr); case iro_Member: return get_Member_entity(ptr); case iro_Sub: case iro_Add: { ir_node *left = get_binop_left(ptr); if (mode_is_reference(get_irn_mode(left))) return find_entity(left); ir_node *right = get_binop_right(ptr); if (mode_is_reference(get_irn_mode(right))) return find_entity(right); return NULL; } default: return NULL; } } /** * Returns true, if the entity that the given pointer points to is * volatile itself, or if it is part of a larger volatile entity. * * If no entity can be found (@see find_entity), the functions assumes * volatility. */ static bool is_inside_volatile_entity(ir_node *ptr) { ir_entity *ent = find_entity(ptr); // TODO Probably a pointer, follow the Load(s) to the actual entity if (!ent) return true; if (get_entity_volatility(ent) == volatility_is_volatile) { return true; } if (is_Sel(ptr)) { ir_node *sel_ptr = get_Sel_ptr(ptr); return is_inside_volatile_entity(sel_ptr); } else { return false; } } /** * Returns true, if the given type is compound and contains at least * one entity which is volatile. */ static bool contains_volatile_entity(ir_type *type) { if (!is_compound_type(type)) return false; for (size_t i = 0, n = get_compound_n_members(type); i < n; ++i) { ir_entity *ent = get_compound_member(type, i); if (get_entity_volatility(ent) == volatility_is_volatile) return true; ir_type *ent_type = get_entity_type(ent); if (contains_volatile_entity(ent_type)) return true; } return false; } /** * Returns true, if the entity that the given pointer points to is... * - volatile itself * - part of a larger volatile entity * - of a type which contains volatile entities. * * If no entity can be found (@see find_entity), the function assumes * volatility. */ bool is_partly_volatile(ir_node *ptr) { ir_entity *ent = find_entity(ptr); if (!ent) return true; ir_type *type = get_entity_type(ent); return contains_volatile_entity(type) || is_inside_volatile_entity(ptr); }