From 1bc5aee63eb72b341f506ad058502cd0361f0d10 Mon Sep 17 00:00:00 2001 From: Ben Cheng Date: Tue, 25 Mar 2014 22:37:19 -0700 Subject: Initial checkin of GCC 4.9.0 from trunk (r208799). Change-Id: I48a3c08bb98542aa215912a75f03c0890e497dba --- gcc-4.9/libobjc/encoding.c | 1274 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 1274 insertions(+) create mode 100644 gcc-4.9/libobjc/encoding.c (limited to 'gcc-4.9/libobjc/encoding.c') diff --git a/gcc-4.9/libobjc/encoding.c b/gcc-4.9/libobjc/encoding.c new file mode 100644 index 000000000..7ecc812a9 --- /dev/null +++ b/gcc-4.9/libobjc/encoding.c @@ -0,0 +1,1274 @@ +/* Encoding of types for Objective C. + Copyright (C) 1993-2014 Free Software Foundation, Inc. + Contributed by Kresten Krab Thorup + Bitfield support by Ovidiu Predescu + +This file is part of GCC. + +GCC is free software; you can redistribute it and/or modify +it under the terms of the GNU General Public License as published by +the Free Software Foundation; either version 3, or (at your option) +any later version. + +GCC is distributed in the hope that it will be useful, +but WITHOUT ANY WARRANTY; without even the implied warranty of +MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +GNU General Public License for more details. + +Under Section 7 of GPL version 3, you are granted additional +permissions described in the GCC Runtime Library Exception, version +3.1, as published by the Free Software Foundation. + +You should have received a copy of the GNU General Public License and +a copy of the GCC Runtime Library Exception along with this program; +see the files COPYING3 and COPYING.RUNTIME respectively. If not, see +. */ + +/* FIXME: This file has no business including tm.h. */ + +/* FIXME: This file contains functions that will abort the entire + program if they fail. Is that really needed ? */ + +#include "objc-private/common.h" +#include "objc-private/error.h" +#include "tconfig.h" +#include "coretypes.h" +#include "tm.h" +#include "objc/runtime.h" +#include "objc-private/module-abi-8.h" /* For struct objc_method */ +#include +#include +#include /* For memcpy. */ + +#undef MAX +#define MAX(X, Y) \ + ({ typeof (X) __x = (X), __y = (Y); \ + (__x > __y ? __x : __y); }) + +#undef MIN +#define MIN(X, Y) \ + ({ typeof (X) __x = (X), __y = (Y); \ + (__x < __y ? __x : __y); }) + +#undef ROUND +#define ROUND(V, A) \ + ({ typeof (V) __v = (V); typeof (A) __a = (A); \ + __a * ((__v+__a - 1)/__a); }) + + +/* Various hacks for objc_layout_record. These are used by the target + macros. */ + +#define TREE_CODE(TYPE) *(TYPE) +#define TREE_TYPE(TREE) (TREE) + +#define RECORD_TYPE _C_STRUCT_B +#define UNION_TYPE _C_UNION_B +#define QUAL_UNION_TYPE _C_UNION_B +#define ARRAY_TYPE _C_ARY_B + +#define REAL_TYPE _C_DBL + +#define VECTOR_TYPE _C_VECTOR + +#define TYPE_FIELDS(TYPE) ({const char *_field = (TYPE)+1; \ + while (*_field != _C_STRUCT_E && *_field != _C_STRUCT_B \ + && *_field != _C_UNION_B && *_field++ != '=') \ + /* do nothing */; \ + _field;}) + +#define DECL_MODE(TYPE) *(TYPE) +#define TYPE_MODE(TYPE) *(TYPE) + +#define DFmode _C_DBL + +#define strip_array_types(TYPE) ({const char *_field = (TYPE); \ + while (*_field == _C_ARY_B)\ + {\ + while (isdigit ((unsigned char)*++_field))\ + ;\ + }\ + _field;}) + +/* Some ports (eg ARM) allow the structure size boundary to be + selected at compile-time. We override the normal definition with + one that has a constant value for this compilation. */ +#ifndef BITS_PER_UNIT +#define BITS_PER_UNIT 8 +#endif +#undef STRUCTURE_SIZE_BOUNDARY +#define STRUCTURE_SIZE_BOUNDARY (BITS_PER_UNIT * sizeof (struct{char a;})) + +/* Some ROUND_TYPE_ALIGN macros use TARGET_foo, and consequently + target_flags. Define a dummy entry here to so we don't die. + We have to rename it because target_flags may already have been + declared extern. */ +#define target_flags not_target_flags +static int __attribute__ ((__unused__)) not_target_flags = 0; + +/* Some ROUND_TYPE_ALIGN use ALTIVEC_VECTOR_MODE (rs6000 darwin). + Define a dummy ALTIVEC_VECTOR_MODE so it will not die. */ +#undef ALTIVEC_VECTOR_MODE +#define ALTIVEC_VECTOR_MODE(MODE) (0) + +/* Replace TARGET_VSX, TARGET_ALTIVEC, and TARGET_64BIT with constants based on + the current switches, rather than looking in the options structure. */ +#ifdef _ARCH_PPC +#undef TARGET_VSX +#undef TARGET_ALTIVEC +#undef TARGET_64BIT + +#ifdef __VSX__ +#define TARGET_VSX 1 +#else +#define TARGET_VSX 0 +#endif + +#ifdef __ALTIVEC__ +#define TARGET_ALTIVEC 1 +#else +#define TARGET_ALTIVEC 0 +#endif + +#ifdef _ARCH_PPC64 +#define TARGET_64BIT 1 +#else +#define TARGET_64BIT 0 +#endif +#endif + +/* Furthermore, some (powerpc) targets also use TARGET_ALIGN_NATURAL + in their alignment macros. Currently[4.5/6], rs6000.h points this + to a static variable, initialized by target overrides. This is reset + in linux64.h but not in darwin64.h. The macro is not used by *86*. */ + +#if __MACH__ +# if __LP64__ +# undef TARGET_ALIGN_NATURAL +# define TARGET_ALIGN_NATURAL 1 +# endif + +/* On Darwin32, we need to recurse until we find the starting stuct type. */ +static int +_darwin_rs6000_special_round_type_align (const char *struc, int comp, int spec) +{ + const char *_stp , *_fields = TYPE_FIELDS (struc); + if (!_fields) + return MAX (comp, spec); + _stp = strip_array_types (_fields); + if (TYPE_MODE(_stp) == _C_COMPLEX) + _stp++; + switch (TYPE_MODE(_stp)) + { + case RECORD_TYPE: + case UNION_TYPE: + return MAX (MAX (comp, spec), objc_alignof_type (_stp) * BITS_PER_UNIT); + break; + case DFmode: + case _C_LNG_LNG: + case _C_ULNG_LNG: + return MAX (MAX (comp, spec), 64); + break; + + default: + return MAX (comp, spec); + break; + } +} + +/* See comment below. */ +#define darwin_rs6000_special_round_type_align(S,C,S2) \ + (_darwin_rs6000_special_round_type_align ((char*)(S), (int)(C), (int)(S2))) +#endif + +/* FIXME: while this file has no business including tm.h, this + definitely has no business defining this macro but it + is only way around without really rewritting this file, + should look after the branch of 3.4 to fix this. */ +#define rs6000_special_round_type_align(STRUCT, COMPUTED, SPECIFIED) \ + ({ const char *_fields = TYPE_FIELDS (STRUCT); \ + ((_fields != 0 \ + && TYPE_MODE (strip_array_types (TREE_TYPE (_fields))) == DFmode) \ + ? MAX (MAX (COMPUTED, SPECIFIED), 64) \ + : MAX (COMPUTED, SPECIFIED));}) + + +/* Skip a variable name, enclosed in quotes ("). */ +static inline +const char * +objc_skip_variable_name (const char *type) +{ + /* Skip the variable name if any. */ + if (*type == '"') + { + /* FIXME: How do we know we won't read beyond the end of the + string. Here and in the rest of the file! */ + /* Skip '"'. */ + type++; + /* Skip to the next '"'. */ + while (*type != '"') + type++; + /* Skip '"'. */ + type++; + } + + return type; +} + +int +objc_sizeof_type (const char *type) +{ + type = objc_skip_variable_name (type); + + switch (*type) { + case _C_BOOL: + return sizeof (_Bool); + break; + + 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_LNG_DBL: + return sizeof (long 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 ((unsigned char)*++type)) + ; + return len * objc_aligned_size (type); + } + break; + + case _C_VECTOR: + { + /* Skip the '!'. */ + type++; + /* Skip the '['. */ + type++; + + /* The size in bytes is the following number. */ + int size = atoi (type); + return size; + } + break; + + case _C_BFLD: + { + /* The GNU encoding of bitfields is: b 'position' 'type' + 'size'. */ + int position, size; + int startByte, endByte; + + position = atoi (type + 1); + while (isdigit ((unsigned char)*++type)) + ; + size = atoi (type + 1); + + startByte = position / BITS_PER_UNIT; + endByte = (position + size) / BITS_PER_UNIT; + return endByte - startByte; + } + + case _C_UNION_B: + 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_COMPLEX: + { + type++; /* Skip after the 'j'. */ + switch (*type) + { + case _C_CHR: + return sizeof (_Complex char); + break; + + case _C_UCHR: + return sizeof (_Complex unsigned char); + break; + + case _C_SHT: + return sizeof (_Complex short); + break; + + case _C_USHT: + return sizeof (_Complex unsigned short); + break; + + case _C_INT: + return sizeof (_Complex int); + break; + + case _C_UINT: + return sizeof (_Complex unsigned int); + break; + + case _C_LNG: + return sizeof (_Complex long); + break; + + case _C_ULNG: + return sizeof (_Complex unsigned long); + break; + + case _C_LNG_LNG: + return sizeof (_Complex long long); + break; + + case _C_ULNG_LNG: + return sizeof (_Complex unsigned long long); + break; + + case _C_FLT: + return sizeof (_Complex float); + break; + + case _C_DBL: + return sizeof (_Complex double); + break; + + case _C_LNG_DBL: + return sizeof (_Complex long double); + break; + + default: + { + /* FIXME: Is this so bad that we have to abort the + entire program ? (it applies to all the other + _objc_abort calls in this file). + */ + _objc_abort ("unknown complex type %s\n", type); + return 0; + } + } + } + + default: + { + _objc_abort ("unknown type %s\n", type); + return 0; + } + } +} + +int +objc_alignof_type (const char *type) +{ + type = objc_skip_variable_name (type); + + switch (*type) { + case _C_BOOL: + return __alignof__ (_Bool); + break; + + case _C_ID: + return __alignof__ (id); + break; + + case _C_CLASS: + return __alignof__ (Class); + break; + + case _C_SEL: + return __alignof__ (SEL); + break; + + case _C_CHR: + return __alignof__ (char); + break; + + case _C_UCHR: + return __alignof__ (unsigned char); + break; + + case _C_SHT: + return __alignof__ (short); + break; + + case _C_USHT: + return __alignof__ (unsigned short); + break; + + case _C_INT: + return __alignof__ (int); + break; + + case _C_UINT: + return __alignof__ (unsigned int); + break; + + case _C_LNG: + return __alignof__ (long); + break; + + case _C_ULNG: + return __alignof__ (unsigned long); + break; + + case _C_LNG_LNG: + return __alignof__ (long long); + break; + + case _C_ULNG_LNG: + return __alignof__ (unsigned long long); + break; + + case _C_FLT: + return __alignof__ (float); + break; + + case _C_DBL: + return __alignof__ (double); + break; + + case _C_LNG_DBL: + return __alignof__ (long double); + break; + + case _C_PTR: + case _C_ATOM: + case _C_CHARPTR: + return __alignof__ (char *); + break; + + case _C_ARY_B: + while (isdigit ((unsigned char)*++type)) + /* do nothing */; + return objc_alignof_type (type); + + case _C_VECTOR: + { + /* Skip the '!'. */ + type++; + /* Skip the '['. */ + type++; + + /* Skip the size. */ + while (isdigit ((unsigned char)*type)) + type++; + + /* Skip the ','. */ + type++; + + /* The alignment in bytes is the following number. */ + return atoi (type); + } + case _C_STRUCT_B: + case _C_UNION_B: + { + struct objc_struct_layout layout; + unsigned int align; + + objc_layout_structure (type, &layout); + while (objc_layout_structure_next_member (&layout)) + /* do nothing */; + objc_layout_finish_structure (&layout, NULL, &align); + + return align; + } + + + case _C_COMPLEX: + { + type++; /* Skip after the 'j'. */ + switch (*type) + { + case _C_CHR: + return __alignof__ (_Complex char); + break; + + case _C_UCHR: + return __alignof__ (_Complex unsigned char); + break; + + case _C_SHT: + return __alignof__ (_Complex short); + break; + + case _C_USHT: + return __alignof__ (_Complex unsigned short); + break; + + case _C_INT: + return __alignof__ (_Complex int); + break; + + case _C_UINT: + return __alignof__ (_Complex unsigned int); + break; + + case _C_LNG: + return __alignof__ (_Complex long); + break; + + case _C_ULNG: + return __alignof__ (_Complex unsigned long); + break; + + case _C_LNG_LNG: + return __alignof__ (_Complex long long); + break; + + case _C_ULNG_LNG: + return __alignof__ (_Complex unsigned long long); + break; + + case _C_FLT: + return __alignof__ (_Complex float); + break; + + case _C_DBL: + return __alignof__ (_Complex double); + break; + + case _C_LNG_DBL: + return __alignof__ (_Complex long double); + break; + + default: + { + _objc_abort ("unknown complex type %s\n", type); + return 0; + } + } + } + + default: + { + _objc_abort ("unknown type %s\n", type); + return 0; + } + } +} + +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); +} + +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); +} + +inline +const char * +objc_skip_type_qualifiers (const char *type) +{ + while (*type == _C_CONST + || *type == _C_IN + || *type == _C_INOUT + || *type == _C_OUT + || *type == _C_BYCOPY + || *type == _C_BYREF + || *type == _C_ONEWAY + || *type == _C_GCINVISIBLE) + { + type += 1; + } + return type; +} + +inline +const char * +objc_skip_typespec (const char *type) +{ + type = objc_skip_variable_name (type); + type = objc_skip_type_qualifiers (type); + + switch (*type) { + + case _C_ID: + /* An id may be annotated by the actual type if it is known + with the @"ClassName" syntax */ + + if (*++type != '"') + return type; + else + { + while (*++type != '"') + /* do nothing */; + return type + 1; + } + + /* The following are one character type codes */ + case _C_CLASS: + case _C_SEL: + case _C_CHR: + case _C_UCHR: + case _C_CHARPTR: + case _C_ATOM: + case _C_SHT: + case _C_USHT: + case _C_INT: + case _C_UINT: + case _C_LNG: + case _C_BOOL: + case _C_ULNG: + case _C_LNG_LNG: + case _C_ULNG_LNG: + case _C_FLT: + case _C_DBL: + case _C_LNG_DBL: + case _C_VOID: + case _C_UNDEF: + return ++type; + break; + + case _C_COMPLEX: + return type + 2; + break; + + case _C_ARY_B: + /* skip digits, typespec and closing ']' */ + while (isdigit ((unsigned char)*++type)) + ; + type = objc_skip_typespec (type); + if (*type == _C_ARY_E) + return ++type; + else + { + _objc_abort ("bad array type %s\n", type); + return 0; + } + + case _C_VECTOR: + /* Skip '!' */ + type++; + /* Skip '[' */ + type++; + /* Skip digits (size) */ + while (isdigit ((unsigned char)*type)) + type++; + /* Skip ',' */ + type++; + /* Skip digits (alignment) */ + while (isdigit ((unsigned char)*type)) + type++; + /* Skip typespec. */ + type = objc_skip_typespec (type); + /* Skip closing ']'. */ + if (*type == _C_ARY_E) + return ++type; + else + { + _objc_abort ("bad vector type %s\n", type); + return 0; + } + + case _C_BFLD: + /* The GNU encoding of bitfields is: b 'position' 'type' + 'size'. */ + while (isdigit ((unsigned char)*++type)) + ; /* skip position */ + while (isdigit ((unsigned char)*++type)) + ; /* skip type and size */ + return type; + + case _C_STRUCT_B: + /* skip name, and elements until closing '}' */ + + while (*type != _C_STRUCT_E && *type++ != '=') + ; + while (*type != _C_STRUCT_E) + { + type = objc_skip_typespec (type); + } + return ++type; + + case _C_UNION_B: + /* skip name, and elements until closing ')' */ + + while (*type != _C_UNION_E && *type++ != '=') + ; + while (*type != _C_UNION_E) + { + type = objc_skip_typespec (type); + } + return ++type; + + case _C_PTR: + /* Just skip the following typespec */ + + return objc_skip_typespec (++type); + + default: + { + _objc_abort ("unknown type %s\n", type); + return 0; + } + } +} + +inline +const char * +objc_skip_offset (const char *type) +{ + /* The offset is prepended by a '+' if the argument is passed in + registers. PS: The compiler stopped generating this '+' in + version 3.4. */ + if (*type == '+') + type++; + + /* Some people claim that on some platforms, where the stack grows + backwards, the compiler generates negative offsets (??). Skip a + '-' for such a negative offset. */ + if (*type == '-') + type++; + + /* Skip the digits that represent the offset. */ + while (isdigit ((unsigned char) *type)) + type++; + + return type; +} + +const char * +objc_skip_argspec (const char *type) +{ + type = objc_skip_typespec (type); + type = objc_skip_offset (type); + return type; +} + +char * +method_copyReturnType (struct objc_method *method) +{ + if (method == NULL) + return 0; + else + { + char *returnValue; + size_t returnValueSize; + + /* Determine returnValueSize. */ + { + /* Find the end of the first argument. We want to return the + first argument spec, plus 1 byte for the \0 at the end. */ + const char *type = method->method_types; + if (*type == '\0') + return NULL; + type = objc_skip_argspec (type); + returnValueSize = type - method->method_types + 1; + } + + /* Copy the first argument into returnValue. */ + returnValue = malloc (sizeof (char) * returnValueSize); + memcpy (returnValue, method->method_types, returnValueSize); + returnValue[returnValueSize - 1] = '\0'; + + return returnValue; + } +} + +char * +method_copyArgumentType (struct objc_method * method, unsigned int argumentNumber) +{ + if (method == NULL) + return 0; + else + { + char *returnValue; + const char *returnValueStart; + size_t returnValueSize; + + /* Determine returnValueStart and returnValueSize. */ + { + const char *type = method->method_types; + + /* Skip the first argument (return type). */ + type = objc_skip_argspec (type); + + /* Now keep skipping arguments until we get to + argumentNumber. */ + while (argumentNumber > 0) + { + /* We are supposed to skip an argument, but the string is + finished. This means we were asked for a non-existing + argument. */ + if (*type == '\0') + return NULL; + + type = objc_skip_argspec (type); + argumentNumber--; + } + + /* If the argument does not exist, return NULL. */ + if (*type == '\0') + return NULL; + + returnValueStart = type; + type = objc_skip_argspec (type); + returnValueSize = type - returnValueStart + 1; + } + + /* Copy the argument into returnValue. */ + returnValue = malloc (sizeof (char) * returnValueSize); + memcpy (returnValue, returnValueStart, returnValueSize); + returnValue[returnValueSize - 1] = '\0'; + + return returnValue; + } +} + +void method_getReturnType (struct objc_method * method, char *returnValue, + size_t returnValueSize) +{ + if (returnValue == NULL || returnValueSize == 0) + return; + + /* Zero the string; we'll then write the argument type at the + beginning of it, if needed. */ + memset (returnValue, 0, returnValueSize); + + if (method == NULL) + return; + else + { + size_t argumentTypeSize; + + /* Determine argumentTypeSize. */ + { + /* Find the end of the first argument. We want to return the + first argument spec. */ + const char *type = method->method_types; + if (*type == '\0') + return; + type = objc_skip_argspec (type); + argumentTypeSize = type - method->method_types; + if (argumentTypeSize > returnValueSize) + argumentTypeSize = returnValueSize; + } + /* Copy the argument at the beginning of the string. */ + memcpy (returnValue, method->method_types, argumentTypeSize); + } +} + +void method_getArgumentType (struct objc_method * method, unsigned int argumentNumber, + char *returnValue, size_t returnValueSize) +{ + if (returnValue == NULL || returnValueSize == 0) + return; + + /* Zero the string; we'll then write the argument type at the + beginning of it, if needed. */ + memset (returnValue, 0, returnValueSize); + + if (method == NULL) + return; + else + { + const char *returnValueStart; + size_t argumentTypeSize; + + /* Determine returnValueStart and argumentTypeSize. */ + { + const char *type = method->method_types; + + /* Skip the first argument (return type). */ + type = objc_skip_argspec (type); + + /* Now keep skipping arguments until we get to + argumentNumber. */ + while (argumentNumber > 0) + { + /* We are supposed to skip an argument, but the string is + finished. This means we were asked for a non-existing + argument. */ + if (*type == '\0') + return; + + type = objc_skip_argspec (type); + argumentNumber--; + } + + /* If the argument does not exist, it's game over. */ + if (*type == '\0') + return; + + returnValueStart = type; + type = objc_skip_argspec (type); + argumentTypeSize = type - returnValueStart; + if (argumentTypeSize > returnValueSize) + argumentTypeSize = returnValueSize; + } + /* Copy the argument at the beginning of the string. */ + memcpy (returnValue, returnValueStart, argumentTypeSize); + } +} + +unsigned int +method_getNumberOfArguments (struct objc_method *method) +{ + if (method == NULL) + return 0; + else + { + unsigned int i = 0; + const char *type = method->method_types; + while (*type) + { + type = objc_skip_argspec (type); + i += 1; + } + + if (i == 0) + { + /* This could only happen if method_types is invalid; in + that case, return 0. */ + return 0; + } + else + { + /* Remove the return type. */ + return (i - 1); + } + } +} + +unsigned +objc_get_type_qualifiers (const char *type) +{ + unsigned res = 0; + BOOL flag = YES; + + while (flag) + switch (*type++) + { + case _C_CONST: res |= _F_CONST; break; + case _C_IN: res |= _F_IN; break; + case _C_INOUT: res |= _F_INOUT; break; + case _C_OUT: res |= _F_OUT; break; + case _C_BYCOPY: res |= _F_BYCOPY; break; + case _C_BYREF: res |= _F_BYREF; break; + case _C_ONEWAY: res |= _F_ONEWAY; break; + case _C_GCINVISIBLE: res |= _F_GCINVISIBLE; break; + default: flag = NO; + } + + return res; +} + +/* The following three functions can be used to determine how a + structure is laid out by the compiler. For example: + + struct objc_struct_layout layout; + int i; + + objc_layout_structure (type, &layout); + while (objc_layout_structure_next_member (&layout)) + { + int position, align; + const char *type; + + objc_layout_structure_get_info (&layout, &position, &align, &type); + printf ("element %d has offset %d, alignment %d\n", + i++, position, align); + } + + These functions are used by objc_sizeof_type and objc_alignof_type + functions to compute the size and alignment of structures. The + previous method of computing the size and alignment of a structure + was not working on some architectures, particularly on AIX, and in + the presence of bitfields inside the structure. */ +void +objc_layout_structure (const char *type, + struct objc_struct_layout *layout) +{ + const char *ntype; + + if (*type != _C_UNION_B && *type != _C_STRUCT_B) + { + _objc_abort ("record (or union) type expected in objc_layout_structure, got %s\n", + type); + } + + type ++; + layout->original_type = type; + + /* Skip "=" if any. Avoid embedded structures and unions. */ + ntype = type; + while (*ntype != _C_STRUCT_E && *ntype != _C_STRUCT_B && *ntype != _C_UNION_B + && *ntype++ != '=') + /* do nothing */; + + /* If there's a "=", ntype - 1 points to '='; skip the the name */ + if (*(ntype - 1) == '=') + type = ntype; + + layout->type = type; + layout->prev_type = NULL; + layout->record_size = 0; + layout->record_align = BITS_PER_UNIT; + + layout->record_align = MAX (layout->record_align, STRUCTURE_SIZE_BOUNDARY); +} + +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 PCC_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; +} + +void objc_layout_finish_structure (struct objc_struct_layout *layout, + unsigned int *size, + unsigned int *align) +{ + BOOL unionp = layout->original_type[-1] == _C_UNION_B; + if (layout->type + && ((!unionp && *layout->type == _C_STRUCT_E) + || (unionp && *layout->type == _C_UNION_E))) + { + /* Work out the alignment of the record as one expression and store + in the record type. Round it up to a multiple of the record's + alignment. */ +#if defined (ROUND_TYPE_ALIGN) && ! defined (__sparc__) + layout->record_align = ROUND_TYPE_ALIGN (layout->original_type-1, + 1, + layout->record_align); +#else + layout->record_align = MAX (1, layout->record_align); +#endif + +#ifdef ROUND_TYPE_SIZE + layout->record_size = ROUND_TYPE_SIZE (layout->original_type, + layout->record_size, + layout->record_align); +#else + /* Round the size up to be a multiple of the required alignment */ + layout->record_size = ROUND (layout->record_size, layout->record_align); +#endif + + layout->type = NULL; + } + if (size) + *size = layout->record_size / BITS_PER_UNIT; + if (align) + *align = layout->record_align / BITS_PER_UNIT; +} + +void objc_layout_structure_get_info (struct objc_struct_layout *layout, + unsigned int *offset, + unsigned int *align, + const char **type) +{ + if (offset) + *offset = layout->record_size / BITS_PER_UNIT; + if (align) + *align = layout->record_align / BITS_PER_UNIT; + if (type) + *type = layout->prev_type; +} -- cgit v1.2.3