diff options
Diffstat (limited to 'gcc/rust/backend/rust-tree.cc')
| -rw-r--r-- | gcc/rust/backend/rust-tree.cc | 46 |
1 files changed, 46 insertions, 0 deletions
diff --git a/gcc/rust/backend/rust-tree.cc b/gcc/rust/backend/rust-tree.cc index 98c112a..82b5845 100644 --- a/gcc/rust/backend/rust-tree.cc +++ b/gcc/rust/backend/rust-tree.cc @@ -4033,4 +4033,50 @@ location_of (tree t) return EXPR_LOCATION (t); } +/* For element type ELT_TYPE, return the appropriate type of the heap object + containing such element(s). COOKIE_SIZE is NULL or the size of cookie + in bytes. FULL_SIZE is NULL if it is unknown how big the heap allocation + will be, otherwise size of the heap object. If COOKIE_SIZE is NULL, + return array type ELT_TYPE[FULL_SIZE / sizeof(ELT_TYPE)], otherwise return + struct { size_t[COOKIE_SIZE/sizeof(size_t)]; ELT_TYPE[N]; } + where N is nothing (flexible array member) if FULL_SIZE is NULL, otherwise + it is computed such that the size of the struct fits into FULL_SIZE. */ + +tree +build_new_constexpr_heap_type (tree elt_type, tree cookie_size, tree full_size) +{ + gcc_assert (cookie_size == NULL_TREE || tree_fits_uhwi_p (cookie_size)); + gcc_assert (full_size == NULL_TREE || tree_fits_uhwi_p (full_size)); + unsigned HOST_WIDE_INT csz = cookie_size ? tree_to_uhwi (cookie_size) : 0; + tree itype2 = NULL_TREE; + if (full_size) + { + unsigned HOST_WIDE_INT fsz = tree_to_uhwi (full_size); + gcc_assert (fsz >= csz); + fsz -= csz; + fsz /= int_size_in_bytes (elt_type); + itype2 = build_index_type (size_int (fsz - 1)); + if (!cookie_size) + return build_cplus_array_type (elt_type, itype2); + } + else + gcc_assert (cookie_size); + csz /= int_size_in_bytes (sizetype); + tree itype1 = build_index_type (size_int (csz - 1)); + tree atype1 = build_cplus_array_type (sizetype, itype1); + tree atype2 = build_cplus_array_type (elt_type, itype2); + tree rtype = cxx_make_type (RECORD_TYPE); + TYPE_NAME (rtype) = heap_identifier; + tree fld1 = build_decl (UNKNOWN_LOCATION, FIELD_DECL, NULL_TREE, atype1); + tree fld2 = build_decl (UNKNOWN_LOCATION, FIELD_DECL, NULL_TREE, atype2); + DECL_FIELD_CONTEXT (fld1) = rtype; + DECL_FIELD_CONTEXT (fld2) = rtype; + DECL_ARTIFICIAL (fld1) = true; + DECL_ARTIFICIAL (fld2) = true; + TYPE_FIELDS (rtype) = fld1; + DECL_CHAIN (fld1) = fld2; + layout_type (rtype); + return rtype; +} + } // namespace Rust |