libffi/src/s390/ffi.c

   1 /* -----------------------------------------------------------------------
   2    ffi.c - Copyright (c) 2000, 2007 Software AG
   3            Copyright (c) 2008 Red Hat, Inc
   4
   5    S390 Foreign Function Interface
   6
   7    Permission is hereby granted, free of charge, to any person obtaining
   8    a copy of this software and associated documentation files (the
   9    ``Software''), to deal in the Software without restriction, including
  10    without limitation the rights to use, copy, modify, merge, publish,
  11    distribute, sublicense, and/or sell copies of the Software, and to
  12    permit persons to whom the Software is furnished to do so, subject to
  13    the following conditions:
  14
  15    The above copyright notice and this permission notice shall be included
  16    in all copies or substantial portions of the Software.
  17
  18    THE SOFTWARE IS PROVIDED ``AS IS'', WITHOUT WARRANTY OF ANY KIND, EXPRESS
  19    OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  20    MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
  21    IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY CLAIM, DAMAGES OR
  22    OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
  23    ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
  24    OTHER DEALINGS IN THE SOFTWARE.
  25    ----------------------------------------------------------------------- */
  26 /*====================================================================*/
  27 /*                          Includes                                  */
  28 /*                          --------                                  */
  29 /*====================================================================*/
  30
  31 #include <ffi.h>
  32 #include <ffi_common.h>
  33
  34 #include <stdlib.h>
  35 #include <stdio.h>
  36
  37 /*====================== End of Includes =============================*/
  38
  39 /*====================================================================*/
  40 /*                           Defines                                  */
  41 /*                           -------                                  */
  42 /*====================================================================*/
  43
  44 /* Maximum number of GPRs available for argument passing.  */
  45 #define MAX_GPRARGS 5
  46
  47 /* Maximum number of FPRs available for argument passing.  */
  48 #ifdef __s390x__
  49 #define MAX_FPRARGS 4
  50 #else
  51 #define MAX_FPRARGS 2
  52 #endif
  53
  54 /* Round to multiple of 16.  */
  55 #define ROUND_SIZE(size) (((size) + 15) & ~15)
  56
  57 /* If these values change, sysv.S must be adapted!  */
  58 #define FFI390_RET_VOID         0
  59 #define FFI390_RET_STRUCT       1
  60 #define FFI390_RET_FLOAT        2
  61 #define FFI390_RET_DOUBLE       3
  62 #define FFI390_RET_INT32        4
  63 #define FFI390_RET_INT64        5
  64
  65 /*===================== End of Defines ===============================*/
  66
  67 /*====================================================================*/
  68 /*                          Prototypes                                */
  69 /*                          ----------                                */
  70 /*====================================================================*/
  71
  72 static void ffi_prep_args (unsigned char *, extended_cif *);
  73 void
  74 #if __GNUC__ > 3 || (__GNUC__ == 3 && __GNUC_MINOR__ > 2)
  75 __attribute__ ((visibility ("hidden")))
  76 #endif
  77 ffi_closure_helper_SYSV (ffi_closure *, unsigned long *,
  78                          unsigned long long *, unsigned long *);
  79
  80 /*====================== End of Prototypes ===========================*/
  81
  82 /*====================================================================*/
  83 /*                          Externals                                 */
  84 /*                          ---------                                 */
  85 /*====================================================================*/
  86
  87 extern void ffi_call_SYSV(unsigned,
  88                           extended_cif *,
  89                           void (*)(unsigned char *, extended_cif *),
  90                           unsigned,
  91                           void *,
  92                           void (*fn)(void));
  93
  94 extern void ffi_closure_SYSV(void);
  95
  96 /*====================== End of Externals ============================*/
  97
  98 /*====================================================================*/
  99 /*                                                                    */
 100 /* Name     - ffi_check_struct_type.                                  */
 101 /*                                                                    */
 102 /* Function - Determine if a structure can be passed within a         */
 103 /*            general purpose or floating point register.             */
 104 /*                                                                    */
 105 /*====================================================================*/
 106
 107 static int
 108 ffi_check_struct_type (ffi_type *arg)
 109 {
 110   size_t size = arg->size;
 111
 112   /* If the struct has just one element, look at that element
 113      to find out whether to consider the struct as floating point.  */
 114   while (arg->type == FFI_TYPE_STRUCT
 115          && arg->elements[0] && !arg->elements[1])
 116     arg = arg->elements[0];
 117
 118   /* Structs of size 1, 2, 4, and 8 are passed in registers,
 119      just like the corresponding int/float types.  */
 120   switch (size)
 121     {
 122       case 1:
 123         return FFI_TYPE_UINT8;
 124
 125       case 2:
 126         return FFI_TYPE_UINT16;
 127
 128       case 4:
 129         if (arg->type == FFI_TYPE_FLOAT)
 130           return FFI_TYPE_FLOAT;
 131         else
 132           return FFI_TYPE_UINT32;
 133
 134       case 8:
 135         if (arg->type == FFI_TYPE_DOUBLE)
 136           return FFI_TYPE_DOUBLE;
 137         else
 138           return FFI_TYPE_UINT64;
 139
 140       default:
 141         break;
 142     }
 143
 144   /* Other structs are passed via a pointer to the data.  */
 145   return FFI_TYPE_POINTER;
 146 }
 147
 148 /*======================== End of Routine ============================*/
 149
 150 /*====================================================================*/
 151 /*                                                                    */
 152 /* Name     - ffi_prep_args.                                          */
 153 /*                                                                    */
 154 /* Function - Prepare parameters for call to function.                */
 155 /*                                                                    */
 156 /* ffi_prep_args is called by the assembly routine once stack space   */
 157 /* has been allocated for the function's arguments.                   */
 158 /*                                                                    */
 159 /*====================================================================*/
 160
 161 static void
 162 ffi_prep_args (unsigned char *stack, extended_cif *ecif)
 163 {
 164   /* The stack space will be filled with those areas:
 165
 166         FPR argument register save area     (highest addresses)
 167         GPR argument register save area
 168         temporary struct copies
 169         overflow argument area              (lowest addresses)
 170
 171      We set up the following pointers:
 172
 173         p_fpr: bottom of the FPR area (growing upwards)
 174         p_gpr: bottom of the GPR area (growing upwards)
 175         p_ov: bottom of the overflow area (growing upwards)
 176         p_struct: top of the struct copy area (growing downwards)
 177
 178      All areas are kept aligned to twice the word size.  */
 179
 180   int gpr_off = ecif->cif->bytes;
 181   int fpr_off = gpr_off + ROUND_SIZE (MAX_GPRARGS * sizeof (long));
 182
 183   unsigned long long *p_fpr = (unsigned long long *)(stack + fpr_off);
 184   unsigned long *p_gpr = (unsigned long *)(stack + gpr_off);
 185   unsigned char *p_struct = (unsigned char *)p_gpr;
 186   unsigned long *p_ov = (unsigned long *)stack;
 187
 188   int n_fpr = 0;
 189   int n_gpr = 0;
 190   int n_ov = 0;
 191
 192   ffi_type **ptr;
 193   void **p_argv = ecif->avalue;
 194   int i;
 195
 196   /* If we returning a structure then we set the first parameter register
 197      to the address of where we are returning this structure.  */
 198
 199   if (ecif->cif->flags == FFI390_RET_STRUCT)
 200     p_gpr[n_gpr++] = (unsigned long) ecif->rvalue;
 201
 202   /* Now for the arguments.  */
 203
 204   for (ptr = ecif->cif->arg_types, i = ecif->cif->nargs;
 205        i > 0;
 206        i--, ptr++, p_argv++)
 207     {
 208       void *arg = *p_argv;
 209       int type = (*ptr)->type;
 210
 211 #if FFI_TYPE_LONGDOUBLE != FFI_TYPE_DOUBLE
 212       /* 16-byte long double is passed like a struct.  */
 213       if (type == FFI_TYPE_LONGDOUBLE)
 214         type = FFI_TYPE_STRUCT;
 215 #endif
 216
 217       /* Check how a structure type is passed.  */
 218       if (type == FFI_TYPE_STRUCT)
 219         {
 220           type = ffi_check_struct_type (*ptr);
 221
 222           /* If we pass the struct via pointer, copy the data.  */
 223           if (type == FFI_TYPE_POINTER)
 224             {
 225               p_struct -= ROUND_SIZE ((*ptr)->size);
 226               memcpy (p_struct, (char *)arg, (*ptr)->size);
 227               arg = &p_struct;
 228             }
 229         }
 230
 231       /* Now handle all primitive int/pointer/float data types.  */
 232       switch (type)
 233         {
 234           case FFI_TYPE_DOUBLE:
 235             if (n_fpr < MAX_FPRARGS)
 236               p_fpr[n_fpr++] = *(unsigned long long *) arg;
 237             else
 238 #ifdef __s390x__
 239               p_ov[n_ov++] = *(unsigned long *) arg;
 240 #else
 241               p_ov[n_ov++] = ((unsigned long *) arg)[0],
 242               p_ov[n_ov++] = ((unsigned long *) arg)[1];
 243 #endif
 244             break;
 245
 246           case FFI_TYPE_FLOAT:
 247             if (n_fpr < MAX_FPRARGS)
 248               p_fpr[n_fpr++] = (long long) *(unsigned int *) arg << 32;
 249             else
 250               p_ov[n_ov++] = *(unsigned int *) arg;
 251             break;
 252
 253           case FFI_TYPE_POINTER:
 254             if (n_gpr < MAX_GPRARGS)
 255               p_gpr[n_gpr++] = (unsigned long)*(unsigned char **) arg;
 256             else
 257               p_ov[n_ov++] = (unsigned long)*(unsigned char **) arg;
 258             break;
 259
 260           case FFI_TYPE_UINT64:
 261           case FFI_TYPE_SINT64:
 262 #ifdef __s390x__
 263             if (n_gpr < MAX_GPRARGS)
 264               p_gpr[n_gpr++] = *(unsigned long *) arg;
 265             else
 266               p_ov[n_ov++] = *(unsigned long *) arg;
 267 #else
 268             if (n_gpr == MAX_GPRARGS-1)
 269               n_gpr = MAX_GPRARGS;
 270             if (n_gpr < MAX_GPRARGS)
 271               p_gpr[n_gpr++] = ((unsigned long *) arg)[0],
 272               p_gpr[n_gpr++] = ((unsigned long *) arg)[1];
 273             else
 274               p_ov[n_ov++] = ((unsigned long *) arg)[0],
 275               p_ov[n_ov++] = ((unsigned long *) arg)[1];
 276 #endif
 277             break;
 278
 279           case FFI_TYPE_UINT32:
 280             if (n_gpr < MAX_GPRARGS)
 281               p_gpr[n_gpr++] = *(unsigned int *) arg;
 282             else
 283               p_ov[n_ov++] = *(unsigned int *) arg;
 284             break;
 285
 286           case FFI_TYPE_INT:
 287           case FFI_TYPE_SINT32:
 288             if (n_gpr < MAX_GPRARGS)
 289               p_gpr[n_gpr++] = *(signed int *) arg;
 290             else
 291               p_ov[n_ov++] = *(signed int *) arg;
 292             break;
 293
 294           case FFI_TYPE_UINT16:
 295             if (n_gpr < MAX_GPRARGS)
 296               p_gpr[n_gpr++] = *(unsigned short *) arg;
 297             else
 298               p_ov[n_ov++] = *(unsigned short *) arg;
 299             break;
 300
 301           case FFI_TYPE_SINT16:
 302             if (n_gpr < MAX_GPRARGS)
 303               p_gpr[n_gpr++] = *(signed short *) arg;
 304             else
 305               p_ov[n_ov++] = *(signed short *) arg;
 306             break;
 307
 308           case FFI_TYPE_UINT8:
 309             if (n_gpr < MAX_GPRARGS)
 310               p_gpr[n_gpr++] = *(unsigned char *) arg;
 311             else
 312               p_ov[n_ov++] = *(unsigned char *) arg;
 313             break;
 314
 315           case FFI_TYPE_SINT8:
 316             if (n_gpr < MAX_GPRARGS)
 317               p_gpr[n_gpr++] = *(signed char *) arg;
 318             else
 319               p_ov[n_ov++] = *(signed char *) arg;
 320             break;
 321
 322           default:
 323             FFI_ASSERT (0);
 324             break;
 325         }
 326     }
 327 }
 328
 329 /*======================== End of Routine ============================*/
 330
 331 /*====================================================================*/
 332 /*                                                                    */
 333 /* Name     - ffi_prep_cif_machdep.                                   */
 334 /*                                                                    */
 335 /* Function - Perform machine dependent CIF processing.               */
 336 /*                                                                    */
 337 /*====================================================================*/
 338
 339 ffi_status
 340 ffi_prep_cif_machdep(ffi_cif *cif)
 341 {
 342   size_t struct_size = 0;
 343   int n_gpr = 0;
 344   int n_fpr = 0;
 345   int n_ov = 0;
 346
 347   ffi_type **ptr;
 348   int i;
 349
 350   /* Determine return value handling.  */
 351
 352   switch (cif->rtype->type)
 353     {
 354       /* Void is easy.  */
 355       case FFI_TYPE_VOID:
 356         cif->flags = FFI390_RET_VOID;
 357         break;
 358
 359       /* Structures are returned via a hidden pointer.  */
 360       case FFI_TYPE_STRUCT:
 361         cif->flags = FFI390_RET_STRUCT;
 362         n_gpr++;  /* We need one GPR to pass the pointer.  */
 363         break;
 364
 365       /* Floating point values are returned in fpr 0.  */
 366       case FFI_TYPE_FLOAT:
 367         cif->flags = FFI390_RET_FLOAT;
 368         break;
 369
 370       case FFI_TYPE_DOUBLE:
 371         cif->flags = FFI390_RET_DOUBLE;
 372         break;
 373
 374 #if FFI_TYPE_LONGDOUBLE != FFI_TYPE_DOUBLE
 375       case FFI_TYPE_LONGDOUBLE:
 376         cif->flags = FFI390_RET_STRUCT;
 377         n_gpr++;
 378         break;
 379 #endif
 380       /* Integer values are returned in gpr 2 (and gpr 3
 381          for 64-bit values on 31-bit machines).  */
 382       case FFI_TYPE_UINT64:
 383       case FFI_TYPE_SINT64:
 384         cif->flags = FFI390_RET_INT64;
 385         break;
 386
 387       case FFI_TYPE_POINTER:
 388       case FFI_TYPE_INT:
 389       case FFI_TYPE_UINT32:
 390       case FFI_TYPE_SINT32:
 391       case FFI_TYPE_UINT16:
 392       case FFI_TYPE_SINT16:
 393       case FFI_TYPE_UINT8:
 394       case FFI_TYPE_SINT8:
 395         /* These are to be extended to word size.  */
 396 #ifdef __s390x__
 397         cif->flags = FFI390_RET_INT64;
 398 #else
 399         cif->flags = FFI390_RET_INT32;
 400 #endif
 401         break;
 402
 403       default:
 404         FFI_ASSERT (0);
 405         break;
 406     }
 407
 408   /* Now for the arguments.  */
 409
 410   for (ptr = cif->arg_types, i = cif->nargs;
 411        i > 0;
 412        i--, ptr++)
 413     {
 414       int type = (*ptr)->type;
 415
 416 #if FFI_TYPE_LONGDOUBLE != FFI_TYPE_DOUBLE
 417       /* 16-byte long double is passed like a struct.  */
 418       if (type == FFI_TYPE_LONGDOUBLE)
 419         type = FFI_TYPE_STRUCT;
 420 #endif
 421
 422       /* Check how a structure type is passed.  */
 423       if (type == FFI_TYPE_STRUCT)
 424         {
 425           type = ffi_check_struct_type (*ptr);
 426
 427           /* If we pass the struct via pointer, we must reserve space
 428              to copy its data for proper call-by-value semantics.  */
 429           if (type == FFI_TYPE_POINTER)
 430             struct_size += ROUND_SIZE ((*ptr)->size);
 431         }
 432
 433       /* Now handle all primitive int/float data types.  */
 434       switch (type)
 435         {
 436           /* The first MAX_FPRARGS floating point arguments
 437              go in FPRs, the rest overflow to the stack.  */
 438
 439           case FFI_TYPE_DOUBLE:
 440             if (n_fpr < MAX_FPRARGS)
 441               n_fpr++;
 442             else
 443               n_ov += sizeof (double) / sizeof (long);
 444             break;
 445
 446           case FFI_TYPE_FLOAT:
 447             if (n_fpr < MAX_FPRARGS)
 448               n_fpr++;
 449             else
 450               n_ov++;
 451             break;
 452
 453           /* On 31-bit machines, 64-bit integers are passed in GPR pairs,
 454              if one is still available, or else on the stack.  If only one
 455              register is free, skip the register (it won't be used for any
 456              subsequent argument either).  */
 457
 458 #ifndef __s390x__
 459           case FFI_TYPE_UINT64:
 460           case FFI_TYPE_SINT64:
 461             if (n_gpr == MAX_GPRARGS-1)
 462               n_gpr = MAX_GPRARGS;
 463             if (n_gpr < MAX_GPRARGS)
 464               n_gpr += 2;
 465             else
 466               n_ov += 2;
 467             break;
 468 #endif
 469
 470           /* Everything else is passed in GPRs (until MAX_GPRARGS
 471              have been used) or overflows to the stack.  */
 472
 473           default:
 474             if (n_gpr < MAX_GPRARGS)
 475               n_gpr++;
 476             else
 477               n_ov++;
 478             break;
 479         }
 480     }
 481
 482   /* Total stack space as required for overflow arguments
 483      and temporary structure copies.  */
 484
 485   cif->bytes = ROUND_SIZE (n_ov * sizeof (long)) + struct_size;
 486
 487   return FFI_OK;
 488 }
 489
 490 /*======================== End of Routine ============================*/
 491
 492 /*====================================================================*/
 493 /*                                                                    */
 494 /* Name     - ffi_call.                                               */
 495 /*                                                                    */
 496 /* Function - Call the FFI routine.                                   */
 497 /*                                                                    */
 498 /*====================================================================*/
 499
 500 void
 501 ffi_call(ffi_cif *cif,
 502          void (*fn)(void),
 503          void *rvalue,
 504          void **avalue)
 505 {
 506   int ret_type = cif->flags;
 507   extended_cif ecif;
 508
 509   ecif.cif    = cif;
 510   ecif.avalue = avalue;
 511   ecif.rvalue = rvalue;
 512
 513   /* If we don't have a return value, we need to fake one.  */
 514   if (rvalue == NULL)
 515     {
 516       if (ret_type == FFI390_RET_STRUCT)
 517         ecif.rvalue = alloca (cif->rtype->size);
 518       else
 519         ret_type = FFI390_RET_VOID;
 520     }
 521
 522   switch (cif->abi)
 523     {
 524       case FFI_SYSV:
 525         ffi_call_SYSV (cif->bytes, &ecif, ffi_prep_args,
 526                        ret_type, ecif.rvalue, fn);
 527         break;
 528
 529       default:
 530         FFI_ASSERT (0);
 531         break;
 532     }
 533 }
 534
 535 /*======================== End of Routine ============================*/
 536
 537 /*====================================================================*/
 538 /*                                                                    */
 539 /* Name     - ffi_closure_helper_SYSV.                                */
 540 /*                                                                    */
 541 /* Function - Call a FFI closure target function.                     */
 542 /*                                                                    */
 543 /*====================================================================*/
 544
 545 void
 546 ffi_closure_helper_SYSV (ffi_closure *closure,
 547                          unsigned long *p_gpr,
 548                          unsigned long long *p_fpr,
 549                          unsigned long *p_ov)
 550 {
 551   unsigned long long ret_buffer;
 552
 553   void *rvalue = &ret_buffer;
 554   void **avalue;
 555   void **p_arg;
 556
 557   int n_gpr = 0;
 558   int n_fpr = 0;
 559   int n_ov = 0;
 560
 561   ffi_type **ptr;
 562   int i;
 563
 564   /* Allocate buffer for argument list pointers.  */
 565
 566   p_arg = avalue = alloca (closure->cif->nargs * sizeof (void *));
 567
 568   /* If we returning a structure, pass the structure address
 569      directly to the target function.  Otherwise, have the target
 570      function store the return value to the GPR save area.  */
 571
 572   if (closure->cif->flags == FFI390_RET_STRUCT)
 573     rvalue = (void *) p_gpr[n_gpr++];
 574
 575   /* Now for the arguments.  */
 576
 577   for (ptr = closure->cif->arg_types, i = closure->cif->nargs;
 578        i > 0;
 579        i--, p_arg++, ptr++)
 580     {
 581       int deref_struct_pointer = 0;
 582       int type = (*ptr)->type;
 583
 584 #if FFI_TYPE_LONGDOUBLE != FFI_TYPE_DOUBLE
 585       /* 16-byte long double is passed like a struct.  */
 586       if (type == FFI_TYPE_LONGDOUBLE)
 587         type = FFI_TYPE_STRUCT;
 588 #endif
 589
 590       /* Check how a structure type is passed.  */
 591       if (type == FFI_TYPE_STRUCT)
 592         {
 593           type = ffi_check_struct_type (*ptr);
 594
 595           /* If we pass the struct via pointer, remember to
 596              retrieve the pointer later.  */
 597           if (type == FFI_TYPE_POINTER)
 598             deref_struct_pointer = 1;
 599         }
 600
 601       /* Pointers are passed like UINTs of the same size.  */
 602       if (type == FFI_TYPE_POINTER)
 603 #ifdef __s390x__
 604         type = FFI_TYPE_UINT64;
 605 #else
 606         type = FFI_TYPE_UINT32;
 607 #endif
 608
 609       /* Now handle all primitive int/float data types.  */
 610       switch (type)
 611         {
 612           case FFI_TYPE_DOUBLE:
 613             if (n_fpr < MAX_FPRARGS)
 614               *p_arg = &p_fpr[n_fpr++];
 615             else
 616               *p_arg = &p_ov[n_ov],
 617               n_ov += sizeof (double) / sizeof (long);
 618             break;
 619
 620           case FFI_TYPE_FLOAT:
 621             if (n_fpr < MAX_FPRARGS)
 622               *p_arg = &p_fpr[n_fpr++];
 623             else
 624               *p_arg = (char *)&p_ov[n_ov++] + sizeof (long) - 4;
 625             break;
 626
 627           case FFI_TYPE_UINT64:
 628           case FFI_TYPE_SINT64:
 629 #ifdef __s390x__
 630             if (n_gpr < MAX_GPRARGS)
 631               *p_arg = &p_gpr[n_gpr++];
 632             else
 633               *p_arg = &p_ov[n_ov++];
 634 #else
 635             if (n_gpr == MAX_GPRARGS-1)
 636               n_gpr = MAX_GPRARGS;
 637             if (n_gpr < MAX_GPRARGS)
 638               *p_arg = &p_gpr[n_gpr], n_gpr += 2;
 639             else
 640               *p_arg = &p_ov[n_ov], n_ov += 2;
 641 #endif
 642             break;
 643
 644           case FFI_TYPE_INT:
 645           case FFI_TYPE_UINT32:
 646           case FFI_TYPE_SINT32:
 647             if (n_gpr < MAX_GPRARGS)
 648               *p_arg = (char *)&p_gpr[n_gpr++] + sizeof (long) - 4;
 649             else
 650               *p_arg = (char *)&p_ov[n_ov++] + sizeof (long) - 4;
 651             break;
 652
 653           case FFI_TYPE_UINT16:
 654           case FFI_TYPE_SINT16:
 655             if (n_gpr < MAX_GPRARGS)
 656               *p_arg = (char *)&p_gpr[n_gpr++] + sizeof (long) - 2;
 657             else
 658               *p_arg = (char *)&p_ov[n_ov++] + sizeof (long) - 2;
 659             break;
 660
 661           case FFI_TYPE_UINT8:
 662           case FFI_TYPE_SINT8:
 663             if (n_gpr < MAX_GPRARGS)
 664               *p_arg = (char *)&p_gpr[n_gpr++] + sizeof (long) - 1;
 665             else
 666               *p_arg = (char *)&p_ov[n_ov++] + sizeof (long) - 1;
 667             break;
 668
 669           default:
 670             FFI_ASSERT (0);
 671             break;
 672         }
 673
 674       /* If this is a struct passed via pointer, we need to
 675          actually retrieve that pointer.  */
 676       if (deref_struct_pointer)
 677         *p_arg = *(void **)*p_arg;
 678     }
 679
 680
 681   /* Call the target function.  */
 682   (closure->fun) (closure->cif, rvalue, avalue, closure->user_data);
 683
 684   /* Convert the return value.  */
 685   switch (closure->cif->rtype->type)
 686     {
 687       /* Void is easy, and so is struct.  */
 688       case FFI_TYPE_VOID:
 689       case FFI_TYPE_STRUCT:
 690 #if FFI_TYPE_LONGDOUBLE != FFI_TYPE_DOUBLE
 691       case FFI_TYPE_LONGDOUBLE:
 692 #endif
 693         break;
 694
 695       /* Floating point values are returned in fpr 0.  */
 696       case FFI_TYPE_FLOAT:
 697         p_fpr[0] = (long long) *(unsigned int *) rvalue << 32;
 698         break;
 699
 700       case FFI_TYPE_DOUBLE:
 701         p_fpr[0] = *(unsigned long long *) rvalue;
 702         break;
 703
 704       /* Integer values are returned in gpr 2 (and gpr 3
 705          for 64-bit values on 31-bit machines).  */
 706       case FFI_TYPE_UINT64:
 707       case FFI_TYPE_SINT64:
 708 #ifdef __s390x__
 709         p_gpr[0] = *(unsigned long *) rvalue;
 710 #else
 711         p_gpr[0] = ((unsigned long *) rvalue)[0],
 712         p_gpr[1] = ((unsigned long *) rvalue)[1];
 713 #endif
 714         break;
 715
 716       case FFI_TYPE_POINTER:
 717       case FFI_TYPE_UINT32:
 718       case FFI_TYPE_UINT16:
 719       case FFI_TYPE_UINT8:
 720         p_gpr[0] = *(unsigned long *) rvalue;
 721         break;
 722
 723       case FFI_TYPE_INT:
 724       case FFI_TYPE_SINT32:
 725       case FFI_TYPE_SINT16:
 726       case FFI_TYPE_SINT8:
 727         p_gpr[0] = *(signed long *) rvalue;
 728         break;
 729
 730       default:
 731         FFI_ASSERT (0);
 732         break;
 733     }
 734 }
 735
 736 /*======================== End of Routine ============================*/
 737
 738 /*====================================================================*/
 739 /*                                                                    */
 740 /* Name     - ffi_prep_closure_loc.                                   */
 741 /*                                                                    */
 742 /* Function - Prepare a FFI closure.                                  */
 743 /*                                                                    */
 744 /*====================================================================*/
 745
 746 ffi_status
 747 ffi_prep_closure_loc (ffi_closure *closure,
 748                       ffi_cif *cif,
 749                       void (*fun) (ffi_cif *, void *, void **, void *),
 750                       void *user_data,
 751                       void *codeloc)
 752 {
 753   if (cif->abi != FFI_SYSV)
 754     return FFI_BAD_ABI;
 755
 756 #ifndef __s390x__
 757   *(short *)&closure->tramp [0] = 0x0d10;   /* basr %r1,0 */
 758   *(short *)&closure->tramp [2] = 0x9801;   /* lm %r0,%r1,6(%r1) */
 759   *(short *)&closure->tramp [4] = 0x1006;
 760   *(short *)&closure->tramp [6] = 0x07f1;   /* br %r1 */
 761   *(long  *)&closure->tramp [8] = (long)codeloc;
 762   *(long  *)&closure->tramp[12] = (long)&ffi_closure_SYSV;
 763 #else
 764   *(short *)&closure->tramp [0] = 0x0d10;   /* basr %r1,0 */
 765   *(short *)&closure->tramp [2] = 0xeb01;   /* lmg %r0,%r1,14(%r1) */
 766   *(short *)&closure->tramp [4] = 0x100e;
 767   *(short *)&closure->tramp [6] = 0x0004;
 768   *(short *)&closure->tramp [8] = 0x07f1;   /* br %r1 */
 769   *(long  *)&closure->tramp[16] = (long)codeloc;
 770   *(long  *)&closure->tramp[24] = (long)&ffi_closure_SYSV;
 771 #endif
 772
 773   closure->cif = cif;
 774   closure->user_data = user_data;
 775   closure->fun = fun;
 776
 777   return FFI_OK;
 778 }
 779
 780 /*======================== End of Routine ============================*/
 781