static void __objc_gc_setup_union (GC_bitmap mask, const char *type, int offset) { /* Sub-optimal, quick implementation: assume the union is made of pointers, set up the mask accordingly. */ int i, size, align; /* Skip the variable name */ if (*type == '"') { for (type++; *type++ != '"';) /* do nothing */; } size = objc_sizeof_type (type); align = objc_alignof_type (type); offset = ROUND (offset, align); for (i = 0; i < size; i += sizeof (void *)) { SET_BIT_FOR_OFFSET (mask, offset); offset += sizeof (void *); } }
int objc_promoted_size (const char *type) { int size, wordsize; type = objc_skip_variable_name (type); size = objc_sizeof_type (type); wordsize = sizeof (void *); return ROUND (size, wordsize); }
int objc_aligned_size (const char *type) { int size, align; type = objc_skip_variable_name (type); size = objc_sizeof_type (type); align = objc_alignof_type (type); return ROUND (size, align); }
/* Given a selector, return the proper forwarding implementation. */ __inline__ IMP __objc_get_forward_imp (SEL sel) { const char *t = sel->sel_types; if (t && (*t == '[' || *t == '(' || *t == '{') #ifdef OBJC_MAX_STRUCT_BY_VALUE && objc_sizeof_type(t) > OBJC_MAX_STRUCT_BY_VALUE #endif ) return (IMP)__objc_block_forward; else if (t && (*t == 'f' || *t == 'd')) return (IMP)__objc_double_forward; else return (IMP)__objc_word_forward; }
int objc_promoted_size (const char* type) { int size, wordsize; /* Skip the variable name */ if (*type == '"') { for (type++; *type++ != '"';) /* do nothing */; } size = objc_sizeof_type (type); wordsize = sizeof (void*); return ROUND (size, wordsize); }
int objc_aligned_size (const char* type) { int size, align; /* Skip the variable name */ if (*type == '"') { for (type++; *type++ != '"';) /* do nothing */; } size = objc_sizeof_type (type); align = objc_alignof_type (type); return ROUND (size, align); }
/* Given a selector, return the proper forwarding implementation. */ IMP __objc_get_forward_imp (id rcv, SEL sel) { /* If a custom forwarding hook was registered, try getting a forwarding function from it. There are two forward routine hooks, one that takes the receiver as an argument and one that does not. */ if (__objc_msg_forward2) { IMP result; if ((result = __objc_msg_forward2 (rcv, sel)) != NULL) return result; } if (__objc_msg_forward) { IMP result; if ((result = __objc_msg_forward (sel)) != NULL) return result; } /* In all other cases, use the default forwarding functions built using __builtin_apply and friends. */ { const char *t = sel->sel_types; if (t && (*t == '[' || *t == '(' || *t == '{') #ifdef OBJC_MAX_STRUCT_BY_VALUE && objc_sizeof_type (t) > OBJC_MAX_STRUCT_BY_VALUE #endif ) return (IMP)__objc_block_forward; else if (t && (*t == 'f' || *t == 'd')) return (IMP)__objc_double_forward; else return (IMP)__objc_word_forward; } }
BOOL objc_layout_structure_next_member (struct objc_struct_layout *layout) { register int desired_align = 0; /* The following are used only if the field is a bitfield */ register const char *bfld_type = 0; register int bfld_type_align = 0, bfld_field_size = 0; /* The current type without the type qualifiers */ const char *type; BOOL unionp = layout->original_type[-1] == _C_UNION_B; /* Add the size of the previous field to the size of the record. */ if (layout->prev_type) { type = objc_skip_type_qualifiers (layout->prev_type); if (unionp) layout->record_size = MAX (layout->record_size, objc_sizeof_type (type) * BITS_PER_UNIT); else if (*type != _C_BFLD) layout->record_size += objc_sizeof_type (type) * BITS_PER_UNIT; else { /* Get the bitfield's type */ for (bfld_type = type + 1; isdigit ((unsigned char)*bfld_type); bfld_type++) /* do nothing */; bfld_type_align = objc_alignof_type (bfld_type) * BITS_PER_UNIT; bfld_field_size = atoi (objc_skip_typespec (bfld_type)); layout->record_size += bfld_field_size; } } if ((unionp && *layout->type == _C_UNION_E) || (!unionp && *layout->type == _C_STRUCT_E)) return NO; /* Skip the variable name if any */ layout->type = objc_skip_variable_name (layout->type); type = objc_skip_type_qualifiers (layout->type); if (*type != _C_BFLD) desired_align = objc_alignof_type (type) * BITS_PER_UNIT; else { desired_align = 1; /* Skip the bitfield's offset */ for (bfld_type = type + 1; isdigit ((unsigned char) *bfld_type); bfld_type++) /* do nothing */; bfld_type_align = objc_alignof_type (bfld_type) * BITS_PER_UNIT; bfld_field_size = atoi (objc_skip_typespec (bfld_type)); } /* The following won't work for vectors. */ #ifdef BIGGEST_FIELD_ALIGNMENT desired_align = MIN (desired_align, BIGGEST_FIELD_ALIGNMENT); #endif #ifdef ADJUST_FIELD_ALIGN desired_align = ADJUST_FIELD_ALIGN (type, desired_align); #endif /* Record must have at least as much alignment as any field. Otherwise, the alignment of the field within the record is meaningless. */ #ifndef HAVE_BITFIELD_TYPE_MATTERS layout->record_align = MAX (layout->record_align, desired_align); #else /* PCC_BITFIELD_TYPE_MATTERS */ if (*type == _C_BFLD) { /* For these machines, a zero-length field does not affect the alignment of the structure as a whole. It does, however, affect the alignment of the next field within the structure. */ if (bfld_field_size) layout->record_align = MAX (layout->record_align, desired_align); else desired_align = objc_alignof_type (bfld_type) * BITS_PER_UNIT; /* A named bit field of declared type `int' forces the entire structure to have `int' alignment. Q1: How is encoded this thing and how to check for it? Q2: How to determine maximum_field_alignment at runtime? */ /* if (DECL_NAME (field) != 0) */ { int type_align = bfld_type_align; #if 0 if (maximum_field_alignment != 0) type_align = MIN (type_align, maximum_field_alignment); else if (DECL_PACKED (field)) type_align = MIN (type_align, BITS_PER_UNIT); #endif layout->record_align = MAX (layout->record_align, type_align); } } else layout->record_align = MAX (layout->record_align, desired_align); #endif /* PCC_BITFIELD_TYPE_MATTERS */ /* Does this field automatically have alignment it needs by virtue of the fields that precede it and the record's own alignment? */ if (*type == _C_BFLD) layout->record_size = atoi (type + 1); else if (layout->record_size % desired_align != 0) { /* No, we need to skip space before this field. Bump the cumulative size to multiple of field alignment. */ layout->record_size = ROUND (layout->record_size, desired_align); } /* Jump to the next field in record. */ layout->prev_type = layout->type; layout->type = objc_skip_typespec (layout->type); /* skip component */ return YES; }
int objc_sizeof_type (const char* type) { /* Skip the variable name if any */ if (*type == '"') { for (type++; *type++ != '"';) /* do nothing */; } switch(*type) { case _C_ID: return sizeof(id); break; case _C_CLASS: return sizeof(Class); break; case _C_SEL: return sizeof(SEL); break; case _C_CHR: return sizeof(char); break; case _C_UCHR: return sizeof(unsigned char); break; case _C_SHT: return sizeof(short); break; case _C_USHT: return sizeof(unsigned short); break; case _C_INT: return sizeof(int); break; case _C_UINT: return sizeof(unsigned int); break; case _C_LNG: return sizeof(long); break; case _C_ULNG: return sizeof(unsigned long); break; case _C_LNG_LNG: return sizeof(long long); break; case _C_ULNG_LNG: return sizeof(unsigned long long); break; case _C_FLT: return sizeof(float); break; case _C_DBL: return sizeof(double); break; case _C_VOID: return sizeof(void); break; case _C_PTR: case _C_ATOM: case _C_CHARPTR: return sizeof(char*); break; case _C_ARY_B: { int len = atoi(type+1); while (isdigit(*++type)); return len*objc_aligned_size (type); } break; case _C_BFLD: { /* The new encoding of bitfields is: b 'position' 'type' 'size' */ int position, size; int startByte, endByte; position = atoi (type + 1); while (isdigit (*++type)); size = atoi (type + 1); startByte = position / BITS_PER_UNIT; endByte = (position + size) / BITS_PER_UNIT; return endByte - startByte; } case _C_STRUCT_B: { struct objc_struct_layout layout; unsigned int size; objc_layout_structure (type, &layout); while (objc_layout_structure_next_member (&layout)) /* do nothing */ ; objc_layout_finish_structure (&layout, &size, NULL); return size; } case _C_UNION_B: { int max_size = 0; while (*type != _C_UNION_E && *type++ != '=') /* do nothing */; while (*type != _C_UNION_E) { /* Skip the variable name if any */ if (*type == '"') { for (type++; *type++ != '"';) /* do nothing */; } max_size = MAX (max_size, objc_sizeof_type (type)); type = objc_skip_typespec (type); } return max_size; } default: { objc_error(nil, OBJC_ERR_BAD_TYPE, "unknown type %s\n", type); return 0; } } }