Adapt the old and unused code for type checking for C23. gcc/c/: * c-typeck.c (struct comptypes_data): Add anon_field flag. (comptypes, comptypes_check_unum_int, comptypes_check_different_types): Remove old cache. (tagged_tu_types_compatible_p): Rewrite. --- gcc/c/c-typeck.cc | 261 +++++++++++----------------------------------- 1 file changed, 58 insertions(+), 203 deletions(-) diff --git a/gcc/c/c-typeck.cc b/gcc/c/c-typeck.cc index ed1520ed6ba..41ef05f005c 100644 --- a/gcc/c/c-typeck.cc +++ b/gcc/c/c-typeck.cc @@ -190,20 +190,14 @@ remove_c_maybe_const_expr (tree expr) return expr; } -/* This is a cache to hold if two types are compatible or not. */ +/* This is a cache to hold if two types are seen. */ struct tagged_tu_seen_cache { const struct tagged_tu_seen_cache * next; const_tree t1; const_tree t2; - /* The return value of tagged_types_tu_compatible_p if we had seen - these two types already. */ - int val; }; -static const struct tagged_tu_seen_cache * tagged_tu_seen_base; -static void free_all_tagged_tu_seen_up_to (const struct tagged_tu_seen_cache *); - /* Do `exp = require_complete_type (loc, exp);' to make sure exp does not have an incomplete type. (That includes void types.) LOC is the location of the use. */ @@ -1043,10 +1037,12 @@ common_type (tree t1, tree t2) } struct comptypes_data { - bool enum_and_int_p; bool different_types_p; bool warning_needed; + bool anon_field; + + const struct tagged_tu_seen_cache* cache; }; /* Return 1 if TYPE1 and TYPE2 are compatible types for assignment @@ -1056,13 +1052,9 @@ struct comptypes_data { int comptypes (tree type1, tree type2) { - const struct tagged_tu_seen_cache * tagged_tu_seen_base1 = tagged_tu_seen_base; - struct comptypes_data data = { }; bool ret = comptypes_internal (type1, type2, &data); - free_all_tagged_tu_seen_up_to (tagged_tu_seen_base1); - return ret ? (data.warning_needed ? 2 : 1) : 0; } @@ -1072,14 +1064,10 @@ comptypes (tree type1, tree type2) int comptypes_check_enum_int (tree type1, tree type2, bool *enum_and_int_p) { - const struct tagged_tu_seen_cache * tagged_tu_seen_base1 = tagged_tu_seen_base; - struct comptypes_data data = { }; bool ret = comptypes_internal (type1, type2, &data); *enum_and_int_p = data.enum_and_int_p; - free_all_tagged_tu_seen_up_to (tagged_tu_seen_base1); - return ret ? (data.warning_needed ? 2 : 1) : 0; } @@ -1090,14 +1078,10 @@ int comptypes_check_different_types (tree type1, tree type2, bool *different_types_p) { - const struct tagged_tu_seen_cache * tagged_tu_seen_base1 = tagged_tu_seen_base; - struct comptypes_data data = { }; bool ret = comptypes_internal (type1, type2, &data); *different_types_p = data.different_types_p; - free_all_tagged_tu_seen_up_to (tagged_tu_seen_base1); - return ret ? (data.warning_needed ? 2 : 1) : 0; } @@ -1334,53 +1318,7 @@ comp_target_types (location_t location, tree ttl, tree ttr) /* Subroutines of `comptypes'. */ - - -/* Allocate the seen two types, assuming that they are compatible. */ - -static struct tagged_tu_seen_cache * -alloc_tagged_tu_seen_cache (const_tree t1, const_tree t2) -{ - struct tagged_tu_seen_cache *tu = XNEW (struct tagged_tu_seen_cache); - tu->next = tagged_tu_seen_base; - tu->t1 = t1; - tu->t2 = t2; - - tagged_tu_seen_base = tu; - - /* The C standard says that two structures in different translation - units are compatible with each other only if the types of their - fields are compatible (among other things). We assume that they - are compatible until proven otherwise when building the cache. - An example where this can occur is: - struct a - { - struct a *next; - }; - If we are comparing this against a similar struct in another TU, - and did not assume they were compatible, we end up with an infinite - loop. */ - tu->val = 1; - return tu; -} - -/* Free the seen types until we get to TU_TIL. */ - -static void -free_all_tagged_tu_seen_up_to (const struct tagged_tu_seen_cache *tu_til) -{ - const struct tagged_tu_seen_cache *tu = tagged_tu_seen_base; - while (tu != tu_til) - { - const struct tagged_tu_seen_cache *const tu1 - = (const struct tagged_tu_seen_cache *) tu; - tu = tu1->next; - XDELETE (CONST_CAST (struct tagged_tu_seen_cache *, tu1)); - } - tagged_tu_seen_base = tu_til; -} - -/* Return 1 if two 'struct', 'union', or 'enum' types T1 and T2 are +/* Return true if two 'struct', 'union', or 'enum' types T1 and T2 are compatible. If the two types are not the same (which has been checked earlier). */ @@ -1406,189 +1344,106 @@ tagged_types_tu_compatible_p (const_tree t1, const_tree t2, && DECL_ORIGINAL_TYPE (TYPE_NAME (t2))) t2 = DECL_ORIGINAL_TYPE (TYPE_NAME (t2)); - /* C90 didn't have the requirement that the two tags be the same. */ - if (flag_isoc99 && TYPE_NAME (t1) != TYPE_NAME (t2)) - return 0; + if (TYPE_NAME (t1) != TYPE_NAME (t2)) + return false; - /* C90 didn't say what happened if one or both of the types were - incomplete; we choose to follow C99 rules here, which is that they - are compatible. */ - if (TYPE_SIZE (t1) == NULL - || TYPE_SIZE (t2) == NULL) - return 1; + if (!data->anon_field && NULL_TREE == TYPE_NAME (t1)) + return false; - { - const struct tagged_tu_seen_cache * tts_i; - for (tts_i = tagged_tu_seen_base; tts_i != NULL; tts_i = tts_i->next) - if (tts_i->t1 == t1 && tts_i->t2 == t2) - return tts_i->val; - } + if (!data->anon_field && TYPE_STUB_DECL (t1) != TYPE_STUB_DECL (t2)) + data->different_types_p = true; + + data->anon_field = false; + + /* Incomplete types are incompatible inside a TU. */ + if (TYPE_SIZE (t1) == NULL || TYPE_SIZE (t2) == NULL) + return false; + + if (ENUMERAL_TYPE != TREE_CODE (t1) + && (TYPE_REVERSE_STORAGE_ORDER (t1) + != TYPE_REVERSE_STORAGE_ORDER (t2))) + return false; + + /* For types already in being looked at in some active + invocation of this function, assume compatibility. + The cache is built as a linked list on the stack + with the head of the list past downwards. */ + for (const struct tagged_tu_seen_cache *t = data->cache; + t != NULL; t = t->next) + if (t->t1 == t1 && t->t2 == t2) + return true; + + const struct tagged_tu_seen_cache entry = { data->cache, t1, t2 }; switch (TREE_CODE (t1)) { case ENUMERAL_TYPE: { - struct tagged_tu_seen_cache *tu = alloc_tagged_tu_seen_cache (t1, t2); /* Speed up the case where the type values are in the same order. */ tree tv1 = TYPE_VALUES (t1); tree tv2 = TYPE_VALUES (t2); if (tv1 == tv2) - { - return 1; - } + return true; for (;tv1 && tv2; tv1 = TREE_CHAIN (tv1), tv2 = TREE_CHAIN (tv2)) { if (TREE_PURPOSE (tv1) != TREE_PURPOSE (tv2)) break; - if (simple_cst_equal (TREE_VALUE (tv1), TREE_VALUE (tv2)) != 1) - { - tu->val = 0; - return 0; - } + + if (simple_cst_equal (DECL_INITIAL (TREE_VALUE (tv1)), + DECL_INITIAL (TREE_VALUE (tv2))) != 1) + break; } if (tv1 == NULL_TREE && tv2 == NULL_TREE) - { - return 1; - } + return true; + if (tv1 == NULL_TREE || tv2 == NULL_TREE) - { - tu->val = 0; - return 0; - } + return false; if (list_length (TYPE_VALUES (t1)) != list_length (TYPE_VALUES (t2))) - { - tu->val = 0; - return 0; - } + return false; for (s1 = TYPE_VALUES (t1); s1; s1 = TREE_CHAIN (s1)) { s2 = purpose_member (TREE_PURPOSE (s1), TYPE_VALUES (t2)); - if (s2 == NULL - || simple_cst_equal (TREE_VALUE (s1), TREE_VALUE (s2)) != 1) - { - tu->val = 0; - return 0; - } - } - return 1; - } - - case UNION_TYPE: - { - struct tagged_tu_seen_cache *tu = alloc_tagged_tu_seen_cache (t1, t2); - - if (list_length (TYPE_FIELDS (t1)) != list_length (TYPE_FIELDS (t2))) - { - tu->val = 0; - return 0; - } - - /* Speed up the common case where the fields are in the same order. */ - for (s1 = TYPE_FIELDS (t1), s2 = TYPE_FIELDS (t2); s1 && s2; - s1 = DECL_CHAIN (s1), s2 = DECL_CHAIN (s2)) - { - int result; - - if (DECL_NAME (s1) != DECL_NAME (s2)) - break; - result = comptypes_internal (TREE_TYPE (s1), TREE_TYPE (s2), data); - - if (result != 1 && !DECL_NAME (s1)) - break; - if (result == 0) - { - tu->val = 0; - return 0; - } - if (TREE_CODE (s1) == FIELD_DECL - && simple_cst_equal (DECL_FIELD_BIT_OFFSET (s1), - DECL_FIELD_BIT_OFFSET (s2)) != 1) - { - tu->val = 0; - return 0; - } - } - if (!s1 && !s2) - { - return tu->val; + if (s2 == NULL + || simple_cst_equal (DECL_INITIAL (TREE_VALUE (s1)), DECL_INITIAL (TREE_VALUE (s2))) != 1) + return false; } - for (s1 = TYPE_FIELDS (t1); s1; s1 = DECL_CHAIN (s1)) - { - bool ok = false; - - for (s2 = TYPE_FIELDS (t2); s2; s2 = DECL_CHAIN (s2)) - if (DECL_NAME (s1) == DECL_NAME (s2)) - { - int result; - - result = comptypes_internal (TREE_TYPE (s1), TREE_TYPE (s2), - data); - - if (result != 1 && !DECL_NAME (s1)) - continue; - if (result == 0) - { - tu->val = 0; - return 0; - } - - if (TREE_CODE (s1) == FIELD_DECL - && simple_cst_equal (DECL_FIELD_BIT_OFFSET (s1), - DECL_FIELD_BIT_OFFSET (s2)) != 1) - break; - - ok = true; - break; - } - if (!ok) - { - tu->val = 0; - return 0; - } - } - return tu->val; + return true; } + case UNION_TYPE: case RECORD_TYPE: - { - struct tagged_tu_seen_cache *tu = alloc_tagged_tu_seen_cache (t1, t2); if (list_length (TYPE_FIELDS (t1)) != list_length (TYPE_FIELDS (t2))) - { - tu->val = 0; - return 0; - } + return false; for (s1 = TYPE_FIELDS (t1), s2 = TYPE_FIELDS (t2); s1 && s2; s1 = DECL_CHAIN (s1), s2 = DECL_CHAIN (s2)) { - int result; if (TREE_CODE (s1) != TREE_CODE (s2) || DECL_NAME (s1) != DECL_NAME (s2)) - break; - result = comptypes_internal (TREE_TYPE (s1), TREE_TYPE (s2), data); - if (result == 0) - break; + return false; + + if (!DECL_NAME (s1) && RECORD_OR_UNION_TYPE_P (TREE_TYPE (s1))) + data->anon_field = true; + + data->cache = &entry; + if (!comptypes_internal (TREE_TYPE (s1), TREE_TYPE (s2), data)) + return false; if (TREE_CODE (s1) == FIELD_DECL && simple_cst_equal (DECL_FIELD_BIT_OFFSET (s1), DECL_FIELD_BIT_OFFSET (s2)) != 1) - break; + return false; } - if (s1 && s2) - tu->val = 0; - else - tu->val = 1; - return tu->val; - } + return true; default: gcc_unreachable (); -- 2.30.2
[C PATCH 2/6] c23: recursive type checking of tagged type
Martin Uecker via Gcc-patches Sat, 26 Aug 2023 09:22:31 -0700
- c23 type compatibility rules, v2 Martin Uecker via Gcc-patches
- [C PATCH 1/6] c: reorganize recursive ... Martin Uecker via Gcc-patches
- Re: [C PATCH 1/6] c: reorganize re... Joseph Myers
- [C PATCH 1/6 v2] c: reorganize... Martin Uecker via Gcc-patches
- Re: [C PATCH 1/6 v2] c: re... Joseph Myers
- [C PATCH 2/6] c23: recursive type check... Martin Uecker via Gcc-patches
- [C PATCH 3/6] c23: tag compatibility ru... Martin Uecker via Gcc-patches
- [C PATCH 4/6] c23: tag compatibility ru... Martin Uecker via Gcc-patches
- [C PATCH 5/6] c23: aliasing of compatib... Martin Uecker via Gcc-patches
- [C PATCH 6/6] c23: construct composite ... Martin Uecker via Gcc-patches
- [C PATCH] c: flag for tag compatibility... Martin Uecker via Gcc-patches