1 /* ----------------------------------------------------------------------- 2 prep_cif.c - Copyright (c) 1996, 1998 Red Hat, Inc. 3 4 Permission is hereby granted, free of charge, to any person obtaining 5 a copy of this software and associated documentation files (the 6 ``Software''), to deal in the Software without restriction, including 7 without limitation the rights to use, copy, modify, merge, publish, 8 distribute, sublicense, and/or sell copies of the Software, and to 9 permit persons to whom the Software is furnished to do so, subject to 10 the following conditions: 11 12 The above copyright notice and this permission notice shall be included 13 in all copies or substantial portions of the Software. 14 15 THE SOFTWARE IS PROVIDED ``AS IS'', WITHOUT WARRANTY OF ANY KIND, EXPRESS 16 OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 17 MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. 18 IN NO EVENT SHALL CYGNUS SOLUTIONS BE LIABLE FOR ANY CLAIM, DAMAGES OR 19 OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, 20 ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR 21 OTHER DEALINGS IN THE SOFTWARE. 22 ----------------------------------------------------------------------- */ 23 24 #include <ffi.h> 25 #include <ffi_common.h> 26 #include <stdlib.h> 27 28 29 /* Round up to FFI_SIZEOF_ARG. */ 30 31 #define STACK_ARG_SIZE(x) ALIGN(x, FFI_SIZEOF_ARG) 32 33 /* Perform machine independent initialization of aggregate type 34 specifications. */ 35 36 static ffi_status initialize_aggregate(/*@out@*/ ffi_type *arg) 37 { 38 ffi_type **ptr; 39 40 FFI_ASSERT(arg != NULL); 41 42 /*@-usedef@*/ 43 44 FFI_ASSERT(arg->elements != NULL); 45 FFI_ASSERT(arg->size == 0); 46 FFI_ASSERT(arg->alignment == 0); 47 48 ptr = &(arg->elements[0]); 49 50 while ((*ptr) != NULL) 51 { 52 if (((*ptr)->size == 0) && (initialize_aggregate((*ptr)) != FFI_OK)) 53 return FFI_BAD_TYPEDEF; 54 55 /* Perform a sanity check on the argument type */ 56 FFI_ASSERT_VALID_TYPE(*ptr); 57 58 arg->size = ALIGN(arg->size, (*ptr)->alignment); 59 arg->size += (*ptr)->size; 60 61 arg->alignment = (arg->alignment > (*ptr)->alignment) ? 62 arg->alignment : (*ptr)->alignment; 63 64 ptr++; 65 } 66 67 /* Structure size includes tail padding. This is important for 68 structures that fit in one register on ABIs like the PowerPC64 69 Linux ABI that right justify small structs in a register. 70 It's also needed for nested structure layout, for example 71 struct A { long a; char b; }; struct B { struct A x; char y; }; 72 should find y at an offset of 2*sizeof(long) and result in a 73 total size of 3*sizeof(long). */ 74 arg->size = ALIGN (arg->size, arg->alignment); 75 76 if (arg->size == 0) 77 return FFI_BAD_TYPEDEF; 78 else 79 return FFI_OK; 80 81 /*@=usedef@*/ 82 } 83 84 /* Perform machine independent ffi_cif preparation, then call 85 machine dependent routine. */ 86 87 ffi_status ffi_prep_cif(/*@out@*/ /*@partial@*/ ffi_cif *cif, 88 ffi_abi abi, unsigned int nargs, 89 /*@dependent@*/ /*@out@*/ /*@partial@*/ ffi_type *rtype, 90 /*@dependent@*/ ffi_type **atypes) 91 { 92 unsigned bytes = 0; 93 unsigned int i; 94 ffi_type **ptr; 95 96 FFI_ASSERT(cif != NULL); 97 FFI_ASSERT((abi > FFI_FIRST_ABI) && (abi <= FFI_DEFAULT_ABI)); 98 99 cif->abi = abi; 100 cif->arg_types = atypes; 101 cif->nargs = nargs; 102 cif->rtype = rtype; 103 104 cif->flags = 0; 105 106 /* Initialize the return type if necessary */ 107 /*@-usedef@*/ 108 if ((cif->rtype->size == 0) && (initialize_aggregate(cif->rtype) != FFI_OK)) 109 return FFI_BAD_TYPEDEF; 110 /*@=usedef@*/ 111 112 /* Perform a sanity check on the return type */ 113 FFI_ASSERT_VALID_TYPE(cif->rtype); 114 115 /* x86-64 and s390 stack space allocation is handled in prep_machdep. */ 116 #if !defined M68K && !defined __x86_64__ && !defined S390 117 /* Make space for the return structure pointer */ 118 if (cif->rtype->type == FFI_TYPE_STRUCT 119 #ifdef _WIN32 120 && (cif->rtype->size > 8) /* MSVC returns small structs in registers */ 121 #endif 122 #ifdef SPARC 123 && (cif->abi != FFI_V9 || cif->rtype->size > 32) 124 #endif 125 ) 126 bytes = STACK_ARG_SIZE(sizeof(void*)); 127 #endif 128 129 for (ptr = cif->arg_types, i = cif->nargs; i > 0; i--, ptr++) 130 { 131 132 /* Initialize any uninitialized aggregate type definitions */ 133 if (((*ptr)->size == 0) && (initialize_aggregate((*ptr)) != FFI_OK)) 134 return FFI_BAD_TYPEDEF; 135 136 /* Perform a sanity check on the argument type, do this 137 check after the initialization. */ 138 FFI_ASSERT_VALID_TYPE(*ptr); 139 140 #if !defined __x86_64__ && !defined S390 141 #ifdef SPARC 142 if (((*ptr)->type == FFI_TYPE_STRUCT 143 && ((*ptr)->size > 16 || cif->abi != FFI_V9)) 144 || ((*ptr)->type == FFI_TYPE_LONGDOUBLE 145 && cif->abi != FFI_V9)) 146 bytes += sizeof(void*); 147 else 148 #elif defined (_WIN64) 149 if ((*ptr)->type == FFI_TYPE_STRUCT && ((*ptr)->size > 8)) 150 bytes += sizeof(void*); 151 else 152 #endif 153 { 154 #if !defined(_MSC_VER) && !defined(__MINGW32__) 155 /* Don't know if this is a libffi bug or not. At least on 156 Windows with MSVC, function call parameters are *not* 157 aligned in the same way as structure fields are, they are 158 only aligned in integer boundaries. 159 160 This doesn't do any harm for cdecl functions and closures, 161 since the caller cleans up the stack, but it is wrong for 162 stdcall functions where the callee cleans. 163 */ 164 165 /* Add any padding if necessary */ 166 if (((*ptr)->alignment - 1) & bytes) 167 bytes = ALIGN(bytes, (*ptr)->alignment); 168 169 #endif 170 bytes += STACK_ARG_SIZE((*ptr)->size); 171 } 172 #endif 173 } 174 175 #ifdef _WIN64 176 /* Function call needs at least 40 bytes stack size, on win64 AMD64 */ 177 if (bytes < 40) 178 bytes = 40; 179 #endif 180 181 cif->bytes = bytes; 182 183 /* Perform machine dependent cif processing */ 184 return ffi_prep_cif_machdep(cif); 185 } 186
