diff options
| -rw-r--r-- | gdb/ChangeLog | 19 | ||||
| -rw-r--r-- | gdb/arch-utils.c | 2 | ||||
| -rw-r--r-- | gdb/cp-abi.c | 6 | ||||
| -rw-r--r-- | gdb/cp-abi.h | 10 | ||||
| -rw-r--r-- | gdb/gnu-v3-abi.c | 49 | ||||
| -rw-r--r-- | gdb/infcall.c | 3 | ||||
| -rw-r--r-- | gdb/language.c | 18 | ||||
| -rw-r--r-- | gdb/language.h | 62 | ||||
| -rw-r--r-- | gdb/tic6x-tdep.c | 2 |
9 files changed, 131 insertions, 40 deletions
diff --git a/gdb/ChangeLog b/gdb/ChangeLog index 5175ebc..3e88754 100644 --- a/gdb/ChangeLog +++ b/gdb/ChangeLog @@ -1,5 +1,24 @@ 2019-12-20 Tankut Baris Aktemur <tankut.baris.aktemur@intel.com> + * language.h (struct language_pass_by_ref_info): New struct. + (struct language_defn)<la_pass_by_reference>: Change the signature + to return a language_pass_by_ref_info instead of an int. + (language_pass_by_reference): Ditto. + (default_pass_by_reference): Ditto. + Adjust the users listed below. + * arch-utils.c (default_return_in_first_hidden_param_p): + Update. + * cp-abi.c (cp_pass_by_reference): Update. + * cp-abi.h (cp_pass_by_reference): Update declaration. + (struct cp_abi_ops)<pass_by_reference>: Update. + * gnu-v3-abi.c (gnuv3_pass_by_reference): Update. + * infcall.c (call_function_by_hand_dummy): Update. + * language.c (language_pass_by_reference): Update. + (default_pass_by_reference): Update. + * tic6x-tdep.c (tic6x_return_value): Update. + +2019-12-20 Tankut Baris Aktemur <tankut.baris.aktemur@intel.com> + * dwarf2read.c (dwarf2_add_member_fn): Read the DW_AT_defaulted and DW_AT_deleted attributes of a function. (read_structure_type): Read the DW_AT_calling_convention attribute diff --git a/gdb/arch-utils.c b/gdb/arch-utils.c index 2129c3b..a1a003f 100644 --- a/gdb/arch-utils.c +++ b/gdb/arch-utils.c @@ -858,7 +858,7 @@ default_return_in_first_hidden_param_p (struct gdbarch *gdbarch, /* Usually, the return value's address is stored the in the "first hidden" parameter if the return value should be passed by reference, as specified in ABI. */ - return language_pass_by_reference (type); + return !(language_pass_by_reference (type).trivially_copyable); } int default_insn_is_call (struct gdbarch *gdbarch, CORE_ADDR addr) diff --git a/gdb/cp-abi.c b/gdb/cp-abi.c index bbb74d4..6503b4c 100644 --- a/gdb/cp-abi.c +++ b/gdb/cp-abi.c @@ -220,11 +220,13 @@ cplus_typename_from_type_info (struct value *value) return (*current_cp_abi.get_typename_from_type_info) (value); } -int +/* See cp-abi.h. */ + +struct language_pass_by_ref_info cp_pass_by_reference (struct type *type) { if ((current_cp_abi.pass_by_reference) == NULL) - return 0; + return default_pass_by_reference (type); return (*current_cp_abi.pass_by_reference) (type); } diff --git a/gdb/cp-abi.h b/gdb/cp-abi.h index 3cbf19c..cc77e0b 100644 --- a/gdb/cp-abi.h +++ b/gdb/cp-abi.h @@ -207,9 +207,11 @@ extern std::string cplus_typename_from_type_info (struct value *value); CORE_ADDR cplus_skip_trampoline (struct frame_info *frame, CORE_ADDR stop_pc); -/* Return non-zero if an argument of type TYPE should be passed by - reference instead of value. */ -extern int cp_pass_by_reference (struct type *type); +/* Return a struct that provides pass-by-reference information + about the given TYPE. */ + +extern struct language_pass_by_ref_info cp_pass_by_reference + (struct type *type); struct cp_abi_ops { @@ -246,7 +248,7 @@ struct cp_abi_ops struct type *(*get_type_from_type_info) (struct value *value); std::string (*get_typename_from_type_info) (struct value *value); CORE_ADDR (*skip_trampoline) (struct frame_info *, CORE_ADDR); - int (*pass_by_reference) (struct type *type); + struct language_pass_by_ref_info (*pass_by_reference) (struct type *type); }; diff --git a/gdb/gnu-v3-abi.c b/gdb/gnu-v3-abi.c index d630ec0..35197e5 100644 --- a/gdb/gnu-v3-abi.c +++ b/gdb/gnu-v3-abi.c @@ -1230,7 +1230,7 @@ gnuv3_skip_trampoline (struct frame_info *frame, CORE_ADDR stop_pc) return real_stop_pc; } -/* Return nonzero if a type should be passed by reference. +/* Return pass-by-reference information for the given TYPE. The rule in the v3 ABI document comes from section 3.1.1. If the type has a non-trivial copy constructor or destructor, then the @@ -1248,22 +1248,33 @@ gnuv3_skip_trampoline (struct frame_info *frame, CORE_ADDR stop_pc) We don't do anything with the constructors or destructors, but we have to get the argument passing right anyway. */ -static int + +static struct language_pass_by_ref_info gnuv3_pass_by_reference (struct type *type) { int fieldnum, fieldelem; type = check_typedef (type); + /* Start with the default values. */ + struct language_pass_by_ref_info info + = default_pass_by_reference (type); + + /* FIXME: Currently, this implementation only fills in the + 'trivially-copyable' field to preserve GDB's existing behavior. */ + /* We're only interested in things that can have methods. */ if (TYPE_CODE (type) != TYPE_CODE_STRUCT && TYPE_CODE (type) != TYPE_CODE_UNION) - return 0; + return info; /* A dynamic class has a non-trivial copy constructor. See c++98 section 12.8 Copying class objects [class.copy]. */ if (gnuv3_dynamic_class (type)) - return 1; + { + info.trivially_copyable = false; + return info; + } for (fieldnum = 0; fieldnum < TYPE_NFN_FIELDS (type); fieldnum++) for (fieldelem = 0; fieldelem < TYPE_FN_FIELDLIST_LENGTH (type, fieldnum); @@ -1280,7 +1291,10 @@ gnuv3_pass_by_reference (struct type *type) /* If we've found a destructor, we must pass this by reference. */ if (name[0] == '~') - return 1; + { + info.trivially_copyable = false; + return info; + } /* If the mangled name of this method doesn't indicate that it is a constructor, we're not interested. @@ -1302,11 +1316,13 @@ gnuv3_pass_by_reference (struct type *type) if (TYPE_CODE (arg_type) == TYPE_CODE_REF) { - struct type *arg_target_type; - - arg_target_type = check_typedef (TYPE_TARGET_TYPE (arg_type)); + struct type *arg_target_type + = check_typedef (TYPE_TARGET_TYPE (arg_type)); if (class_types_same_p (arg_target_type, type)) - return 1; + { + info.trivially_copyable = false; + return info; + } } } } @@ -1319,11 +1335,18 @@ gnuv3_pass_by_reference (struct type *type) about recursive loops here, since we are only looking at members of complete class type. Also ignore any static members. */ for (fieldnum = 0; fieldnum < TYPE_NFIELDS (type); fieldnum++) - if (! field_is_static (&TYPE_FIELD (type, fieldnum)) - && gnuv3_pass_by_reference (TYPE_FIELD_TYPE (type, fieldnum))) - return 1; + if (!field_is_static (&TYPE_FIELD (type, fieldnum))) + { + struct language_pass_by_ref_info field_info + = gnuv3_pass_by_reference (TYPE_FIELD_TYPE (type, fieldnum)); + if (!field_info.trivially_copyable) + { + info.trivially_copyable = false; + return info; + } + } - return 0; + return info; } static void diff --git a/gdb/infcall.c b/gdb/infcall.c index 5553fc9..f3664d5 100644 --- a/gdb/infcall.c +++ b/gdb/infcall.c @@ -1020,7 +1020,8 @@ call_function_by_hand_dummy (struct value *function, args[i] = value_arg_coerce (gdbarch, args[i], param_type, prototyped); - if (param_type != NULL && language_pass_by_reference (param_type)) + if (param_type != NULL + && !(language_pass_by_reference (param_type).trivially_copyable)) args[i] = value_addr (args[i]); } diff --git a/gdb/language.c b/gdb/language.c index 76efc49..ac74c7f 100644 --- a/gdb/language.c +++ b/gdb/language.c @@ -652,21 +652,23 @@ language_class_name_from_physname (const struct language_defn *lang, return NULL; } -/* Return non-zero if TYPE should be passed (and returned) by - reference at the language level. */ -int +/* Return information about whether TYPE should be passed + (and returned) by reference at the language level. */ + +struct language_pass_by_ref_info language_pass_by_reference (struct type *type) { return current_language->la_pass_by_reference (type); } -/* Return zero; by default, types are passed by value at the language - level. The target ABI may pass or return some structs by reference - independent of this. */ -int +/* Return a default struct that provides pass-by-reference information + about the given TYPE. Languages should update the default values + as appropriate. */ + +struct language_pass_by_ref_info default_pass_by_reference (struct type *type) { - return 0; + return {}; } /* Return the default string containing the list of characters diff --git a/gdb/language.h b/gdb/language.h index 14d6fac..f6cd29b 100644 --- a/gdb/language.h +++ b/gdb/language.h @@ -128,6 +128,47 @@ struct language_arch_info struct type *bool_type_default; }; +/* In a language (particularly C++) a function argument of an aggregate + type (i.e. class/struct/union) may be implicitly passed by reference + even though it is declared a call-by-value argument in the source. + The struct below puts together necessary information for GDB to be + able to detect and carry out pass-by-reference semantics for a + particular type. This type is referred as T in the inlined comments + below. + + The default values of the fields are chosen to give correct semantics + for primitive types and for simple aggregate types, such as + + class T { + int x; + }; */ + +struct language_pass_by_ref_info +{ + /* True if an argument of type T can be passed to a function by value + (i.e. not through an implicit reference). False, otherwise. */ + bool trivially_copyable = true; + + /* True if a copy of a value of type T can be initialized by + memcpy'ing the value bit-by-bit. False, otherwise. + E.g. If T has a user-defined copy ctor, this should be false. */ + bool trivially_copy_constructible = true; + + /* True if a value of type T can be destructed simply by reclaiming + the memory area occupied by the value. False, otherwise. + E.g. If T has a user-defined destructor, this should be false. */ + bool trivially_destructible = true; + + /* True if it is allowed to create a copy of a value of type T. + False, otherwise. + E.g. If T has a deleted copy ctor, this should be false. */ + bool copy_constructible = true; + + /* True if a value of type T can be destructed. False, otherwise. + E.g. If T has a deleted destructor, this should be false. */ + bool destructible = true; +}; + /* Structure tying together assorted information about a language. */ struct language_defn @@ -356,9 +397,10 @@ struct language_defn struct ui_file *stream, const struct value_print_options *options); - /* Return non-zero if TYPE should be passed (and returned) by - reference at the language level. */ - int (*la_pass_by_reference) (struct type *type); + /* Return information about whether TYPE should be passed + (and returned) by reference at the language level. */ + struct language_pass_by_ref_info (*la_pass_by_reference) + (struct type *type); /* Return an expression that can be used for a location watchpoint. TYPE is a pointer type that points to the memory @@ -613,14 +655,14 @@ extern void default_print_array_index (struct value *index_value, struct ui_file *stream, const struct value_print_options *options); -/* Return non-zero if TYPE should be passed (and returned) by - reference at the language level. */ -int language_pass_by_reference (struct type *type); +/* Return information about whether TYPE should be passed + (and returned) by reference at the language level. */ +struct language_pass_by_ref_info language_pass_by_reference (struct type *type); -/* Return zero; by default, types are passed by value at the language - level. The target ABI may pass or return some structs by reference - independent of this. */ -int default_pass_by_reference (struct type *type); +/* Return a default struct that provides pass-by-reference information + about the given TYPE. Languages should update the default values + as appropriate. */ +struct language_pass_by_ref_info default_pass_by_reference (struct type *type); /* The default implementation of la_print_typedef. */ void default_print_typedef (struct type *type, struct symbol *new_symbol, diff --git a/gdb/tic6x-tdep.c b/gdb/tic6x-tdep.c index 2df83c4..ca059f9 100644 --- a/gdb/tic6x-tdep.c +++ b/gdb/tic6x-tdep.c @@ -784,7 +784,7 @@ tic6x_return_value (struct gdbarch *gdbarch, struct value *function, if (type != NULL) { type = check_typedef (type); - if (language_pass_by_reference (type)) + if (!(language_pass_by_reference (type).trivially_copyable)) return RETURN_VALUE_STRUCT_CONVENTION; } } |