+/* Compares type A to type B returns 1 if the represent the same type
+ 0 otherwise. */
+
+int
+types_equal (struct type *a, struct type *b)
+{
+ /* Identical type pointers. */
+ /* However, this still doesn't catch all cases of same type for b
+ and a. The reason is that builtin types are different from
+ the same ones constructed from the object. */
+ if (a == b)
+ return 1;
+
+ /* Resolve typedefs */
+ if (TYPE_CODE (a) == TYPE_CODE_TYPEDEF)
+ a = check_typedef (a);
+ if (TYPE_CODE (b) == TYPE_CODE_TYPEDEF)
+ b = check_typedef (b);
+
+ /* If after resolving typedefs a and b are not of the same type
+ code then they are not equal. */
+ if (TYPE_CODE (a) != TYPE_CODE (b))
+ return 0;
+
+ /* If a and b are both pointers types or both reference types then
+ they are equal of the same type iff the objects they refer to are
+ of the same type. */
+ if (TYPE_CODE (a) == TYPE_CODE_PTR
+ || TYPE_CODE (a) == TYPE_CODE_REF)
+ return types_equal (TYPE_TARGET_TYPE (a),
+ TYPE_TARGET_TYPE (b));
+
+ /* Well, damnit, if the names are exactly the same, I'll say they
+ are exactly the same. This happens when we generate method
+ stubs. The types won't point to the same address, but they
+ really are the same. */
+
+ if (TYPE_NAME (a) && TYPE_NAME (b)
+ && strcmp (TYPE_NAME (a), TYPE_NAME (b)) == 0)
+ return 1;
+
+ /* Check if identical after resolving typedefs. */
+ if (a == b)
+ return 1;
+
+ /* Two function types are equal if their argument and return types
+ are equal. */
+ if (TYPE_CODE (a) == TYPE_CODE_FUNC)
+ {
+ int i;
+
+ if (TYPE_NFIELDS (a) != TYPE_NFIELDS (b))
+ return 0;
+
+ if (!types_equal (TYPE_TARGET_TYPE (a), TYPE_TARGET_TYPE (b)))
+ return 0;
+
+ for (i = 0; i < TYPE_NFIELDS (a); ++i)
+ if (!types_equal (TYPE_FIELD_TYPE (a, i), TYPE_FIELD_TYPE (b, i)))
+ return 0;
+
+ return 1;
+ }
+
+ return 0;
+}
+\f
+/* Deep comparison of types. */
+
+/* An entry in the type-equality bcache. */
+
+typedef struct type_equality_entry
+{
+ struct type *type1, *type2;
+} type_equality_entry_d;
+
+DEF_VEC_O (type_equality_entry_d);
+
+/* A helper function to compare two strings. Returns 1 if they are
+ the same, 0 otherwise. Handles NULLs properly. */
+
+static int
+compare_maybe_null_strings (const char *s, const char *t)
+{
+ if (s == NULL && t != NULL)
+ return 0;
+ else if (s != NULL && t == NULL)
+ return 0;
+ else if (s == NULL && t== NULL)
+ return 1;
+ return strcmp (s, t) == 0;
+}
+
+/* A helper function for check_types_worklist that checks two types for
+ "deep" equality. Returns non-zero if the types are considered the
+ same, zero otherwise. */
+
+static int
+check_types_equal (struct type *type1, struct type *type2,
+ VEC (type_equality_entry_d) **worklist)
+{
+ CHECK_TYPEDEF (type1);
+ CHECK_TYPEDEF (type2);
+
+ if (type1 == type2)
+ return 1;
+
+ if (TYPE_CODE (type1) != TYPE_CODE (type2)
+ || TYPE_LENGTH (type1) != TYPE_LENGTH (type2)
+ || TYPE_UNSIGNED (type1) != TYPE_UNSIGNED (type2)
+ || TYPE_NOSIGN (type1) != TYPE_NOSIGN (type2)
+ || TYPE_VARARGS (type1) != TYPE_VARARGS (type2)
+ || TYPE_VECTOR (type1) != TYPE_VECTOR (type2)
+ || TYPE_NOTTEXT (type1) != TYPE_NOTTEXT (type2)
+ || TYPE_INSTANCE_FLAGS (type1) != TYPE_INSTANCE_FLAGS (type2)
+ || TYPE_NFIELDS (type1) != TYPE_NFIELDS (type2))
+ return 0;
+
+ if (!compare_maybe_null_strings (TYPE_TAG_NAME (type1),
+ TYPE_TAG_NAME (type2)))
+ return 0;
+ if (!compare_maybe_null_strings (TYPE_NAME (type1), TYPE_NAME (type2)))
+ return 0;
+
+ if (TYPE_CODE (type1) == TYPE_CODE_RANGE)
+ {
+ if (memcmp (TYPE_RANGE_DATA (type1), TYPE_RANGE_DATA (type2),
+ sizeof (*TYPE_RANGE_DATA (type1))) != 0)
+ return 0;
+ }
+ else
+ {
+ int i;
+
+ for (i = 0; i < TYPE_NFIELDS (type1); ++i)
+ {
+ const struct field *field1 = &TYPE_FIELD (type1, i);
+ const struct field *field2 = &TYPE_FIELD (type2, i);
+ struct type_equality_entry entry;
+
+ if (FIELD_ARTIFICIAL (*field1) != FIELD_ARTIFICIAL (*field2)
+ || FIELD_BITSIZE (*field1) != FIELD_BITSIZE (*field2)
+ || FIELD_LOC_KIND (*field1) != FIELD_LOC_KIND (*field2))
+ return 0;
+ if (!compare_maybe_null_strings (FIELD_NAME (*field1),
+ FIELD_NAME (*field2)))
+ return 0;
+ switch (FIELD_LOC_KIND (*field1))
+ {
+ case FIELD_LOC_KIND_BITPOS:
+ if (FIELD_BITPOS (*field1) != FIELD_BITPOS (*field2))
+ return 0;
+ break;
+ case FIELD_LOC_KIND_ENUMVAL:
+ if (FIELD_ENUMVAL (*field1) != FIELD_ENUMVAL (*field2))
+ return 0;
+ break;
+ case FIELD_LOC_KIND_PHYSADDR:
+ if (FIELD_STATIC_PHYSADDR (*field1)
+ != FIELD_STATIC_PHYSADDR (*field2))
+ return 0;
+ break;
+ case FIELD_LOC_KIND_PHYSNAME:
+ if (!compare_maybe_null_strings (FIELD_STATIC_PHYSNAME (*field1),
+ FIELD_STATIC_PHYSNAME (*field2)))
+ return 0;
+ break;
+ case FIELD_LOC_KIND_DWARF_BLOCK:
+ {
+ struct dwarf2_locexpr_baton *block1, *block2;
+
+ block1 = FIELD_DWARF_BLOCK (*field1);
+ block2 = FIELD_DWARF_BLOCK (*field2);
+ if (block1->per_cu != block2->per_cu
+ || block1->size != block2->size
+ || memcmp (block1->data, block2->data, block1->size) != 0)
+ return 0;
+ }
+ break;
+ default:
+ internal_error (__FILE__, __LINE__, _("Unsupported field kind "
+ "%d by check_types_equal"),
+ FIELD_LOC_KIND (*field1));
+ }
+
+ entry.type1 = FIELD_TYPE (*field1);
+ entry.type2 = FIELD_TYPE (*field2);
+ VEC_safe_push (type_equality_entry_d, *worklist, &entry);
+ }
+ }
+
+ if (TYPE_TARGET_TYPE (type1) != NULL)
+ {
+ struct type_equality_entry entry;
+
+ if (TYPE_TARGET_TYPE (type2) == NULL)
+ return 0;
+
+ entry.type1 = TYPE_TARGET_TYPE (type1);
+ entry.type2 = TYPE_TARGET_TYPE (type2);
+ VEC_safe_push (type_equality_entry_d, *worklist, &entry);
+ }
+ else if (TYPE_TARGET_TYPE (type2) != NULL)
+ return 0;
+
+ return 1;
+}
+
+/* Check types on a worklist for equality. Returns zero if any pair
+ is not equal, non-zero if they are all considered equal. */
+
+static int
+check_types_worklist (VEC (type_equality_entry_d) **worklist,
+ struct bcache *cache)
+{
+ while (!VEC_empty (type_equality_entry_d, *worklist))
+ {
+ struct type_equality_entry entry;
+ int added;
+
+ entry = *VEC_last (type_equality_entry_d, *worklist);
+ VEC_pop (type_equality_entry_d, *worklist);
+
+ /* If the type pair has already been visited, we know it is
+ ok. */
+ bcache_full (&entry, sizeof (entry), cache, &added);
+ if (!added)
+ continue;
+
+ if (check_types_equal (entry.type1, entry.type2, worklist) == 0)
+ return 0;
+ }
+
+ return 1;
+}
+
+/* Return non-zero if types TYPE1 and TYPE2 are equal, as determined by a
+ "deep comparison". Otherwise return zero. */
+
+int
+types_deeply_equal (struct type *type1, struct type *type2)
+{
+ volatile struct gdb_exception except;
+ int result = 0;
+ struct bcache *cache;
+ VEC (type_equality_entry_d) *worklist = NULL;
+ struct type_equality_entry entry;
+
+ gdb_assert (type1 != NULL && type2 != NULL);
+
+ /* Early exit for the simple case. */
+ if (type1 == type2)
+ return 1;
+
+ cache = bcache_xmalloc (NULL, NULL);
+
+ entry.type1 = type1;
+ entry.type2 = type2;
+ VEC_safe_push (type_equality_entry_d, worklist, &entry);
+
+ TRY_CATCH (except, RETURN_MASK_ALL)
+ {
+ result = check_types_worklist (&worklist, cache);
+ }
+ /* check_types_worklist calls several nested helper functions,
+ some of which can raise a GDB Exception, so we just check
+ and rethrow here. If there is a GDB exception, a comparison
+ is not capable (or trusted), so exit. */
+ bcache_xfree (cache);
+ VEC_free (type_equality_entry_d, worklist);
+ /* Rethrow if there was a problem. */
+ if (except.reason < 0)
+ throw_exception (except);
+
+ return result;
+}
+\f