This patch adds a lang hook for defining a struct/RECORD_TYPE “as if” it had appeared directly in the source code. It follows the similar existing hook for enums.
It's the caller's responsibility to create the fields (as FIELD_DECLs) but the hook's responsibility to create and declare the associated RECORD_TYPE. For now the hook is hard-coded to do the equivalent of: typedef struct NAME { FIELDS } NAME; but this could be controlled by an extra parameter if some callers want a different behaviour in future. The motivating use case is to allow the long list of struct definitions in arm_neon.h to be provided by the compiler, which in turn unblocks various arm_neon.h optimisations. Tested on aarch64-linux-gnu, individually and with a follow-on patch from Jonathan that makes use of the hook. OK to install? Richard gcc/ * langhooks.h (lang_hooks_for_types::simulate_record_decl): New hook. * langhooks-def.h (lhd_simulate_record_decl): Declare. (LANG_HOOKS_SIMULATE_RECORD_DECL): Define. (LANG_HOOKS_FOR_TYPES_INITIALIZER): Include it. * langhooks.c (lhd_simulate_record_decl): New function. gcc/c/ * c-tree.h (c_simulate_record_decl): Declare. * c-objc-common.h (LANG_HOOKS_SIMULATE_RECORD_DECL): Override. * c-decl.c (c_simulate_record_decl): New function. gcc/cp/ * decl.c: Include langhooks-def.h. (cxx_simulate_record_decl): New function. * cp-objcp-common.h (cxx_simulate_record_decl): Declare. (LANG_HOOKS_SIMULATE_RECORD_DECL): Override. --- gcc/c/c-decl.c | 31 +++++++++++++++++++++++++++++++ gcc/c/c-objc-common.h | 2 ++ gcc/c/c-tree.h | 2 ++ gcc/cp/cp-objcp-common.h | 4 ++++ gcc/cp/decl.c | 38 ++++++++++++++++++++++++++++++++++++++ gcc/langhooks-def.h | 4 ++++ gcc/langhooks.c | 21 +++++++++++++++++++++ gcc/langhooks.h | 10 ++++++++++ 8 files changed, 112 insertions(+) diff --git a/gcc/c/c-decl.c b/gcc/c/c-decl.c index 771efa3eadf..8d1324b118c 100644 --- a/gcc/c/c-decl.c +++ b/gcc/c/c-decl.c @@ -9436,6 +9436,37 @@ c_simulate_enum_decl (location_t loc, const char *name, input_location = saved_loc; return enumtype; } + +/* Implement LANG_HOOKS_SIMULATE_RECORD_DECL. */ + +tree +c_simulate_record_decl (location_t loc, const char *name, + array_slice<const tree> fields) +{ + location_t saved_loc = input_location; + input_location = loc; + + class c_struct_parse_info *struct_info; + tree ident = get_identifier (name); + tree type = start_struct (loc, RECORD_TYPE, ident, &struct_info); + + for (unsigned int i = 0; i < fields.size (); ++i) + { + DECL_FIELD_CONTEXT (fields[i]) = type; + if (i > 0) + DECL_CHAIN (fields[i - 1]) = fields[i]; + } + + finish_struct (loc, type, fields[0], NULL_TREE, struct_info); + + tree decl = build_decl (loc, TYPE_DECL, ident, type); + TYPE_NAME (type) = decl; + TYPE_STUB_DECL (type) = decl; + lang_hooks.decls.pushdecl (decl); + + input_location = saved_loc; + return type; +} /* Create the FUNCTION_DECL for a function definition. DECLSPECS, DECLARATOR and ATTRIBUTES are the parts of diff --git a/gcc/c/c-objc-common.h b/gcc/c/c-objc-common.h index 7d35a0621e4..f4e8271f06c 100644 --- a/gcc/c/c-objc-common.h +++ b/gcc/c/c-objc-common.h @@ -81,6 +81,8 @@ along with GCC; see the file COPYING3. If not see #undef LANG_HOOKS_SIMULATE_ENUM_DECL #define LANG_HOOKS_SIMULATE_ENUM_DECL c_simulate_enum_decl +#undef LANG_HOOKS_SIMULATE_RECORD_DECL +#define LANG_HOOKS_SIMULATE_RECORD_DECL c_simulate_record_decl #undef LANG_HOOKS_TYPE_FOR_MODE #define LANG_HOOKS_TYPE_FOR_MODE c_common_type_for_mode #undef LANG_HOOKS_TYPE_FOR_SIZE diff --git a/gcc/c/c-tree.h b/gcc/c/c-tree.h index d50d0cb7f2d..8578d2d1e77 100644 --- a/gcc/c/c-tree.h +++ b/gcc/c/c-tree.h @@ -598,6 +598,8 @@ extern tree finish_struct (location_t, tree, tree, tree, class c_struct_parse_info *); extern tree c_simulate_enum_decl (location_t, const char *, vec<string_int_pair> *); +extern tree c_simulate_record_decl (location_t, const char *, + array_slice<const tree>); extern struct c_arg_info *build_arg_info (void); extern struct c_arg_info *get_parm_info (bool, tree); extern tree grokfield (location_t, struct c_declarator *, diff --git a/gcc/cp/cp-objcp-common.h b/gcc/cp/cp-objcp-common.h index f1704aad557..d5859406e8f 100644 --- a/gcc/cp/cp-objcp-common.h +++ b/gcc/cp/cp-objcp-common.h @@ -39,6 +39,8 @@ extern bool cp_handle_option (size_t, const char *, HOST_WIDE_INT, int, extern tree cxx_make_type_hook (tree_code); extern tree cxx_simulate_enum_decl (location_t, const char *, vec<string_int_pair> *); +extern tree cxx_simulate_record_decl (location_t, const char *, + array_slice<const tree>); /* Lang hooks that are shared between C++ and ObjC++ are defined here. Hooks specific to C++ or ObjC++ go in cp/cp-lang.c and objcp/objcp-lang.c, @@ -139,6 +141,8 @@ extern tree cxx_simulate_enum_decl (location_t, const char *, #define LANG_HOOKS_MAKE_TYPE cxx_make_type_hook #undef LANG_HOOKS_SIMULATE_ENUM_DECL #define LANG_HOOKS_SIMULATE_ENUM_DECL cxx_simulate_enum_decl +#undef LANG_HOOKS_SIMULATE_RECORD_DECL +#define LANG_HOOKS_SIMULATE_RECORD_DECL cxx_simulate_record_decl #undef LANG_HOOKS_TYPE_FOR_MODE #define LANG_HOOKS_TYPE_FOR_MODE c_common_type_for_mode #undef LANG_HOOKS_TYPE_FOR_SIZE diff --git a/gcc/cp/decl.c b/gcc/cp/decl.c index 58ddc6a537e..38f065c1c36 100644 --- a/gcc/cp/decl.c +++ b/gcc/cp/decl.c @@ -56,6 +56,7 @@ along with GCC; see the file COPYING3. If not see #include "context.h" /* For 'g'. */ #include "omp-general.h" #include "omp-offload.h" /* For offload_vars. */ +#include "langhooks-def.h" /* For lhd_simulate_record_decl */ /* Possible cases of bad specifiers type used by bad_specifiers. */ enum bad_spec_place { @@ -16597,6 +16598,43 @@ cxx_simulate_enum_decl (location_t loc, const char *name, input_location = saved_loc; return enumtype; } + +/* Implement LANG_HOOKS_SIMULATE_RECORD_DECL. */ + +tree +cxx_simulate_record_decl (location_t loc, const char *name, + array_slice<const tree> fields) +{ + iloc_sentinel ils (loc); + + tree ident = get_identifier (name); + tree type = xref_tag (/*tag_code=*/record_type, ident); + if (type != error_mark_node + && (TREE_CODE (type) != RECORD_TYPE || COMPLETE_TYPE_P (type))) + { + error ("redefinition of %q#T", type); + type = error_mark_node; + } + if (type == error_mark_node) + return lhd_simulate_record_decl (loc, name, fields); + + xref_basetypes (type, NULL_TREE); + type = begin_class_definition (type); + if (type == error_mark_node) + return lhd_simulate_record_decl (loc, name, fields); + + for (tree field : fields) + finish_member_declaration (field); + + type = finish_struct (type, NULL_TREE); + + tree decl = build_decl (loc, TYPE_DECL, ident, type); + TYPE_NAME (type) = decl; + TYPE_STUB_DECL (type) = decl; + lang_hooks.decls.pushdecl (decl); + + return type; +} /* We're defining DECL. Make sure that its type is OK. */ diff --git a/gcc/langhooks-def.h b/gcc/langhooks-def.h index 02b4681dd96..5f17620aaeb 100644 --- a/gcc/langhooks-def.h +++ b/gcc/langhooks-def.h @@ -56,6 +56,8 @@ extern void lhd_overwrite_decl_assembler_name (tree decl, tree name); extern bool lhd_warn_unused_global_decl (const_tree); extern tree lhd_simulate_enum_decl (location_t, const char *, vec<string_int_pair> *); +extern tree lhd_simulate_record_decl (location_t, const char *, + array_slice<const tree>); extern tree lhd_type_for_size (unsigned precision, int unsignedp); extern void lhd_incomplete_type_error (location_t, const_tree, const_tree); extern tree lhd_type_promotes_to (tree); @@ -183,6 +185,7 @@ extern tree lhd_unit_size_without_reusable_padding (tree); #define LANG_HOOKS_MAKE_TYPE lhd_make_node #define LANG_HOOKS_SIMULATE_ENUM_DECL lhd_simulate_enum_decl +#define LANG_HOOKS_SIMULATE_RECORD_DECL lhd_simulate_record_decl #define LANG_HOOKS_CLASSIFY_RECORD NULL #define LANG_HOOKS_TYPE_FOR_SIZE lhd_type_for_size #define LANG_HOOKS_INCOMPLETE_TYPE_ERROR lhd_incomplete_type_error @@ -217,6 +220,7 @@ extern tree lhd_unit_size_without_reusable_padding (tree); #define LANG_HOOKS_FOR_TYPES_INITIALIZER { \ LANG_HOOKS_MAKE_TYPE, \ LANG_HOOKS_SIMULATE_ENUM_DECL, \ + LANG_HOOKS_SIMULATE_RECORD_DECL, \ LANG_HOOKS_CLASSIFY_RECORD, \ LANG_HOOKS_TYPE_FOR_MODE, \ LANG_HOOKS_TYPE_FOR_SIZE, \ diff --git a/gcc/langhooks.c b/gcc/langhooks.c index 48c72377778..b54da177137 100644 --- a/gcc/langhooks.c +++ b/gcc/langhooks.c @@ -516,6 +516,27 @@ lhd_simulate_enum_decl (location_t loc, const char *name, return enumtype; } +/* Default implementation of LANG_HOOKS_SIMULATE_RECORD_DECL. + Just create a normal RECORD_TYPE and a TYPE_DECL for it. */ +tree +lhd_simulate_record_decl (location_t loc, const char *name, + array_slice<const tree> fields) +{ + for (unsigned int i = 1; i < fields.size (); ++i) + /* Reversed by finish_builtin_struct. */ + DECL_CHAIN (fields[i]) = fields[i - 1]; + + tree type = lang_hooks.types.make_type (RECORD_TYPE); + finish_builtin_struct (type, name, fields.back (), NULL_TREE); + + tree decl = build_decl (loc, TYPE_DECL, get_identifier (name), type); + TYPE_NAME (type) = decl; + TYPE_STUB_DECL (type) = decl; + lang_hooks.decls.pushdecl (decl); + + return type; +} + /* Default implementation of LANG_HOOKS_TYPE_FOR_SIZE. Return an integer type with PRECISION bits of precision, that is unsigned if UNSIGNEDP is nonzero, otherwise signed. */ diff --git a/gcc/langhooks.h b/gcc/langhooks.h index ffd3e0bf2db..3e89134e8b4 100644 --- a/gcc/langhooks.h +++ b/gcc/langhooks.h @@ -68,6 +68,16 @@ struct lang_hooks_for_types them all with the given source location. */ tree (*simulate_enum_decl) (location_t, const char *, vec<string_int_pair> *); + /* Do the equivalent of: + + typedef struct NAME { FIELDS; } NAME; + + associating it with location LOC. Return the associated RECORD_TYPE. + + FIELDS is a list of FIELD_DECLs, in layout order. */ + tree (*simulate_record_decl) (location_t loc, const char *name, + array_slice<const tree> fields); + /* Return what kind of RECORD_TYPE this is, mainly for purposes of debug information. If not defined, record types are assumed to be structures. */