mono/mini/mini-amd64-gsharedvt.c

   1 /*
   2  * mini-amd64-gsharedvt.c: libcorkscrew-based native unwinder
   3  *
   4  * Authors:
   5  *   Zoltan Varga <vargaz@gmail.com>
   6  *   Rodrigo Kumpera <kumpera@gmail.com>
   7  *   Andi McClure <andi.mcclure@xamarin.com>
   8  *   Johan Lorensson <johan.lorensson@xamarin.com>
   9  *
  10  * Copyright 2015 Xamarin, Inc (http://www.xamarin.com)
  11  * Licensed under the MIT license. See LICENSE file in the project root for full license information.
  12  */
  13 #include <config.h>
  14 #include <glib.h>
  15
  16 #include <mono/metadata/abi-details.h>
  17 #include <mono/metadata/appdomain.h>
  18 #include <mono/metadata/marshal.h>
  19 #include <mono/metadata/tabledefs.h>
  20 #include <mono/metadata/mono-debug-debugger.h>
  21 #include <mono/metadata/profiler-private.h>
  22 #include <mono/metadata/gc-internals.h>
  23 #include <mono/arch/amd64/amd64-codegen.h>
  24
  25 #include <mono/utils/memcheck.h>
  26
  27 #include "mini.h"
  28 #include "mini-amd64.h"
  29 #include "mini-amd64-gsharedvt.h"
  30 #include "debugger-agent.h"
  31
  32 #if defined (MONO_ARCH_GSHAREDVT_SUPPORTED)
  33
  34 #define ALIGN_TO(val,align) ((((guint64)val) + ((align) - 1)) & ~((align) - 1))
  35
  36 gboolean
  37 mono_arch_gsharedvt_sig_supported (MonoMethodSignature *sig)
  38 {
  39         return FALSE;
  40 }
  41
  42 static const char*
  43 storage_name (ArgStorage st)
  44 {
  45         switch (st) {
  46         case ArgInIReg: return "ArgInIReg";
  47         case ArgInFloatSSEReg: return "ArgInFloatSSEReg";
  48         case ArgInDoubleSSEReg: return "ArgInDoubleSSEReg";
  49         case ArgOnStack: return "ArgOnStack";
  50         case ArgValuetypeInReg: return "ArgValuetypeInReg";
  51         case ArgValuetypeAddrInIReg: return "ArgValuetypeAddrInIReg";
  52         case ArgValuetypeAddrOnStack: return "ArgValuetypeAddrOnStack";
  53         case ArgGSharedVtInReg: return "ArgGSharedVtInReg";
  54         case ArgGSharedVtOnStack: return "ArgGSharedVtOnStack";
  55         case ArgNone: return "ArgNone";
  56         default: return "unknown";
  57         }
  58 }
  59
  60 static char *
  61 arg_info_desc (ArgInfo *info)
  62 {
  63         GString *str = g_string_new ("");
  64
  65         g_string_append_printf (str, "offset %d reg %s storage %s nregs %d", info->offset, mono_arch_regname (info->reg), storage_name (info->storage), info->nregs);
  66         if (info->storage == ArgValuetypeInReg)
  67                 g_string_append_printf (str, " {(%s %s), (%s %s)",
  68                         storage_name (info->pair_storage [0]),
  69                         mono_arch_regname (info->pair_regs [0]),
  70                         storage_name (info->pair_storage [1]),
  71                         mono_arch_regname (info->pair_regs [1]));
  72
  73         return g_string_free (str, FALSE);
  74 }
  75
  76 static inline void
  77 add_to_map (GPtrArray *map, int src, int dst)
  78 {
  79         g_ptr_array_add (map, GUINT_TO_POINTER (src));
  80         g_ptr_array_add (map, GUINT_TO_POINTER (dst));
  81 }
  82
  83 /*
  84  * Slot mapping:
  85  *
  86  * System V:
  87  * 0..5  - rdi, rsi, rdx, rcx, r8, r9
  88  * 6..13 - xmm0..xmm7
  89  * 14..  - stack slots
  90  *
  91  * Windows:
  92  * 0..3 - rcx, rdx, r8, r9
  93  * 4..7 - xmm0..xmm3
  94  * 8..  - stack slots
  95  *
  96  */
  97 static inline int
  98 map_reg (int reg)
  99 {
 100         int i = 0;
 101         for (i = 0; i < PARAM_REGS; ++i) {
 102                 if (param_regs [i] == reg)
 103                         return i;
 104         }
 105         g_error ("Invalid argument register number %d", reg);
 106         return -1;
 107 }
 108
 109 static inline int
 110 map_freg (int reg)
 111 {
 112         return reg + PARAM_REGS;
 113 }
 114
 115 static inline int
 116 map_stack_slot (int slot)
 117 {
 118         return slot + PARAM_REGS + FLOAT_PARAM_REGS;
 119 }
 120
 121 /*
 122 Format for the source descriptor:
 123
 124
 125 Format for the destination descriptor:
 126         bits 0:15  - source register
 127         bits 16:23 - return marshal
 128         bits 24:32 - slot count
 129 */
 130 #define SRC_DESCRIPTOR_MARSHAL_SHIFT 16
 131 #define SRC_DESCRIPTOR_MARSHAL_MASK 0x0Ff
 132
 133 #define SLOT_COUNT_SHIFT 24
 134 #define SLOT_COUNT_MASK 0xff
 135 #define SLOT_BYTE_SIZE 8
 136
 137 static int
 138 get_arg_slots (ArgInfo *ainfo, int **out_slots, gboolean is_source_argument)
 139 {
 140         int sreg = ainfo->reg;
 141         int sslot = ainfo->offset / 8;
 142         int *src = NULL;
 143         int i, nsrc;
 144
 145         switch (ainfo->storage) {
 146         case ArgInIReg:
 147                 nsrc = 1;
 148                 src = g_malloc (nsrc * sizeof (int));
 149                 src [0] = map_reg (sreg);
 150                 break;
 151         case ArgValuetypeInReg:
 152                 nsrc = ainfo->nregs;
 153                 src = g_malloc (nsrc * sizeof (int));
 154                 for (i = 0; i < ainfo->nregs; ++i)
 155                         src [i] = map_reg (ainfo->pair_regs [i]);
 156                 break;
 157         case ArgOnStack:
 158                 nsrc = ainfo->arg_size / SLOT_BYTE_SIZE;
 159                 src = g_malloc (nsrc * sizeof (int));
 160                 // is_source_argument adds 2 because we're skipping over the old BBP and the return address
 161                 // XXX this is a very fragile setup as changes in alignment for the caller reg array can cause the magic number be 3
 162                 for (i = 0; i < nsrc; ++i)
 163                         src [i] = map_stack_slot (sslot + i + (is_source_argument ? 2 : 0));
 164                 break;
 165         case ArgInDoubleSSEReg:
 166         case ArgInFloatSSEReg:
 167                 nsrc = 1;
 168                 src = g_malloc (nsrc * sizeof (int));
 169                 src [0] = map_freg (sreg);
 170                 break;
 171         case ArgValuetypeAddrInIReg:
 172                 nsrc = 1;
 173                 src = g_malloc (nsrc * sizeof (int));
 174                 src [0] = map_reg (ainfo->pair_regs [0]);
 175                 break;
 176         case ArgValuetypeAddrOnStack:
 177                 nsrc = 1;
 178                 src = g_malloc (nsrc * sizeof (int));
 179                 // is_source_argument adds 2 because we're skipping over the old BBP and the return address
 180                 // XXX this is a very fragile setup as changes in alignment for the caller reg array can cause the magic number be 3
 181                 src [0] = map_stack_slot (sslot + (is_source_argument ? 2 : 0));
 182                 break;
 183         default:
 184                 NOT_IMPLEMENTED;
 185                 break;
 186         }
 187
 188         *out_slots = src;
 189         return nsrc;
 190 }
 191
 192 // Once src is known, operate on the dst
 193 static void
 194 handle_marshal_when_src_gsharedvt (ArgInfo *dst_info, int *arg_marshal, int *arg_slots)
 195 {
 196         switch (dst_info->storage) {
 197                 case ArgInIReg:
 198                 case ArgInDoubleSSEReg:
 199                 case ArgInFloatSSEReg:
 200                         *arg_marshal = GSHAREDVT_ARG_BYREF_TO_BYVAL;
 201                         *arg_slots = 1;
 202                         break;
 203                 case ArgOnStack:
 204                         *arg_marshal = GSHAREDVT_ARG_BYREF_TO_BYVAL;
 205                         g_assert (dst_info->arg_size % SLOT_BYTE_SIZE == 0); // Assert quadword aligned
 206                         *arg_slots = dst_info->arg_size / SLOT_BYTE_SIZE;
 207                         break;
 208                 case ArgValuetypeInReg:
 209                         *arg_marshal = GSHAREDVT_ARG_BYREF_TO_BYVAL;
 210                         *arg_slots = dst_info->nregs;
 211                         break;
 212                 case ArgValuetypeAddrInIReg:
 213                 case ArgValuetypeAddrOnStack:
 214                         *arg_marshal = GSHAREDVT_ARG_NONE;
 215                         *arg_slots = dst_info->nregs;
 216                         break;
 217                 default:
 218                         NOT_IMPLEMENTED; // Inappropriate value: if dst and src are gsharedvt at once, we shouldn't be here
 219                         break;
 220         }
 221 }
 222
 223 // Once dst is known, operate on the src
 224 static void
 225 handle_marshal_when_dst_gsharedvt (ArgInfo *src_info, int *arg_marshal)
 226 {
 227         switch (src_info->storage) {
 228                 case ArgInIReg:
 229                 case ArgInDoubleSSEReg:
 230                 case ArgInFloatSSEReg:
 231                 case ArgValuetypeInReg:
 232                 case ArgOnStack:
 233                         *arg_marshal = GSHAREDVT_ARG_BYVAL_TO_BYREF;
 234                         break;
 235                 case ArgValuetypeAddrInIReg:
 236                 case ArgValuetypeAddrOnStack:
 237                         *arg_marshal = GSHAREDVT_ARG_NONE;
 238                         break;
 239                 default:
 240                         NOT_IMPLEMENTED; // See above
 241                         break;
 242         }
 243 }
 244
 245 static void
 246 handle_map_when_gsharedvt_in_reg (ArgInfo *reg_info, int *n, int **map)
 247 {
 248         *n = 1;
 249         *map = g_new0 (int, 1);
 250         (*map) [0] = map_reg (reg_info->reg);
 251 }
 252
 253 static void
 254 handle_map_when_gsharedvt_on_stack (ArgInfo *reg_info, int *n, int **map, gboolean is_source_argument)
 255 {
 256         *n = 1;
 257         *map = g_new0 (int, 1);
 258         int sslot = reg_info->offset / SLOT_BYTE_SIZE;
 259         (*map) [0] = map_stack_slot (sslot + (is_source_argument ? 2 : 0)); // see get_arg_slots
 260 }
 261
 262 gpointer
 263 mono_arch_get_gsharedvt_call_info (gpointer addr, MonoMethodSignature *normal_sig, MonoMethodSignature *gsharedvt_sig, gboolean gsharedvt_in, gint32 vcall_offset, gboolean calli)
 264 {
 265         GSharedVtCallInfo *info;
 266         CallInfo *caller_cinfo, *callee_cinfo;
 267         MonoMethodSignature *caller_sig, *callee_sig;
 268         int aindex, i;
 269         gboolean var_ret = FALSE;
 270         CallInfo *cinfo, *gcinfo;
 271         MonoMethodSignature *sig, *gsig;
 272         GPtrArray *map;
 273
 274         if (gsharedvt_in) {
 275                 caller_sig = normal_sig;
 276                 callee_sig = gsharedvt_sig;
 277                 caller_cinfo = mono_arch_get_call_info (NULL, caller_sig);
 278                 callee_cinfo = mono_arch_get_call_info (NULL, callee_sig);
 279         } else {
 280                 callee_sig = normal_sig;
 281                 caller_sig = gsharedvt_sig;
 282                 callee_cinfo = mono_arch_get_call_info (NULL, callee_sig);
 283                 caller_cinfo = mono_arch_get_call_info (NULL, caller_sig);
 284         }
 285
 286         /*
 287          * If GSHAREDVT_IN is true, this means we are transitioning from normal to gsharedvt code. The caller uses the
 288          * normal call signature, while the callee uses the gsharedvt signature.
 289          * If GSHAREDVT_IN is false, its the other way around.
 290          */
 291
 292         /* sig/cinfo describes the normal call, while gsig/gcinfo describes the gsharedvt call */
 293         if (gsharedvt_in) {
 294                 sig = caller_sig;
 295                 gsig = callee_sig;
 296                 cinfo = caller_cinfo;
 297                 gcinfo = callee_cinfo;
 298         } else {
 299                 sig = callee_sig;
 300                 gsig = caller_sig;
 301                 cinfo = callee_cinfo;
 302                 gcinfo = caller_cinfo;
 303         }
 304
 305         DEBUG_AMD64_GSHAREDVT_PRINT ("source sig: (%s) return (%s)\n", mono_signature_get_desc (caller_sig, FALSE), mono_type_full_name (mono_signature_get_return_type (caller_sig))); // Leak
 306         DEBUG_AMD64_GSHAREDVT_PRINT ("dest sig: (%s) return (%s)\n", mono_signature_get_desc (callee_sig, FALSE), mono_type_full_name (mono_signature_get_return_type (callee_sig)));
 307
 308         if (gcinfo->ret.storage == ArgGsharedvtVariableInReg) {
 309                 /*
 310                  * The return type is gsharedvt
 311                  */
 312                 var_ret = TRUE;
 313         }
 314
 315         /*
 316          * The stack looks like this:
 317          * <arguments>
 318          * <trampoline frame>
 319          * <call area>
 320          * We have to map the stack slots in <arguments> to the stack slots in <call area>.
 321          */
 322         map = g_ptr_array_new ();
 323
 324         for (aindex = 0; aindex < cinfo->nargs; ++aindex) {
 325                 ArgInfo *src_info = &caller_cinfo->args [aindex];
 326                 ArgInfo *dst_info = &callee_cinfo->args [aindex];
 327                 int *src = NULL, *dst = NULL;
 328                 int nsrc = -1, ndst = -1, nslots = 0;
 329
 330                 int arg_marshal = GSHAREDVT_ARG_NONE;
 331                 int arg_slots = 0; // Size in quadwords
 332                 DEBUG_AMD64_GSHAREDVT_PRINT ("-- arg %d in (%s) out (%s)\n", aindex, arg_info_desc (src_info), arg_info_desc (dst_info));
 333
 334                 switch (src_info->storage) {
 335                 case ArgInIReg:
 336                 case ArgInDoubleSSEReg:
 337                 case ArgInFloatSSEReg:
 338                 case ArgValuetypeInReg:
 339                 case ArgOnStack:
 340                         nsrc = get_arg_slots (src_info, &src, TRUE);
 341                         break;
 342                 case ArgGSharedVtInReg:
 343                         handle_marshal_when_src_gsharedvt (dst_info, &arg_marshal, &arg_slots);
 344                         handle_map_when_gsharedvt_in_reg (src_info, &nsrc, &src);
 345                         break;
 346                 case ArgGSharedVtOnStack:
 347                         handle_marshal_when_src_gsharedvt (dst_info, &arg_marshal, &arg_slots);
 348                         handle_map_when_gsharedvt_on_stack (src_info, &nsrc, &src, TRUE);
 349                         break;
 350                 case ArgValuetypeAddrInIReg:
 351                 case ArgValuetypeAddrOnStack:
 352                         nsrc = get_arg_slots (src_info, &src, TRUE);
 353                         break;
 354                 default:
 355                         g_error ("Gsharedvt can't handle source arg type %d", (int)src_info->storage); // Inappropriate value: ArgValuetypeAddrInIReg is for returns only
 356                 }
 357
 358                 switch (dst_info->storage) {
 359                 case ArgInIReg:
 360                 case ArgInDoubleSSEReg:
 361                 case ArgInFloatSSEReg:
 362                 case ArgOnStack:
 363                 case ArgValuetypeInReg:
 364                         ndst = get_arg_slots (dst_info, &dst, FALSE);
 365                         break;
 366                 case ArgGSharedVtInReg:
 367                         handle_marshal_when_dst_gsharedvt (src_info, &arg_marshal);
 368                         handle_map_when_gsharedvt_in_reg (dst_info, &ndst, &dst);
 369                         break;
 370                 case ArgGSharedVtOnStack:
 371                         handle_marshal_when_dst_gsharedvt (src_info, &arg_marshal);
 372                         handle_map_when_gsharedvt_on_stack (dst_info, &ndst, &dst, FALSE);
 373                         break;
 374                 case ArgValuetypeAddrInIReg:
 375                 case ArgValuetypeAddrOnStack:
 376                         ndst = get_arg_slots (dst_info, &dst, FALSE);
 377                         break;
 378                 default:
 379                         g_error ("Gsharedvt can't handle dest arg type %d", (int)dst_info->storage); // See above
 380                 }
 381                 if (nsrc)
 382                         src [0] |= (arg_marshal << SRC_DESCRIPTOR_MARSHAL_SHIFT) | (arg_slots << SLOT_COUNT_SHIFT);
 383
 384                 /* Merge and add to the global list*/
 385                 nslots = MIN (nsrc, ndst);
 386                 DEBUG_AMD64_GSHAREDVT_PRINT ("nsrc %d ndst %d\n", nsrc, ndst);
 387
 388                 for (i = 0; i < nslots; ++i)
 389                         add_to_map (map, src [i], dst [i]);
 390
 391                 g_free (src);
 392                 g_free (dst);
 393         }
 394
 395         DEBUG_AMD64_GSHAREDVT_PRINT ("-- return in (%s) out (%s) var_ret %d\n", arg_info_desc (&caller_cinfo->ret),  arg_info_desc (&callee_cinfo->ret), var_ret);
 396
 397         if (cinfo->ret.storage == ArgValuetypeAddrInIReg) {
 398                 /* Both the caller and the callee pass the vtype ret address in r8 (System V) and RCX or RDX (Windows) */
 399                 g_assert (gcinfo->ret.storage == ArgValuetypeAddrInIReg || gcinfo->ret.storage == ArgGsharedvtVariableInReg);
 400                 add_to_map (map, map_reg (cinfo->ret.reg), map_reg (cinfo->ret.reg));
 401         }
 402
 403         info = mono_domain_alloc0 (mono_domain_get (), sizeof (GSharedVtCallInfo) + (map->len * sizeof (int)));
 404         info->addr = addr;
 405         info->stack_usage = callee_cinfo->stack_usage;
 406         info->ret_marshal = GSHAREDVT_RET_NONE;
 407         info->gsharedvt_in = gsharedvt_in ? 1 : 0;
 408         info->vret_slot = -1;
 409         info->calli = calli;
 410
 411         if (var_ret) {
 412                 g_assert (gcinfo->ret.storage == ArgGsharedvtVariableInReg);
 413                 info->vret_arg_reg = map_reg (gcinfo->ret.reg);
 414                 DEBUG_AMD64_GSHAREDVT_PRINT ("mapping vreg_arg_reg to %d in reg %s\n", info->vret_arg_reg, mono_arch_regname (gcinfo->ret.reg));
 415         } else {
 416                 info->vret_arg_reg = -1;
 417         }
 418
 419 #ifdef DEBUG_AMD64_GSHAREDVT
 420         printf ("final map:\n");
 421         for (i = 0; i < map->len; i += 2) {
 422                 printf ("\t[%d] src %x dst %x\n ",
 423                         i / 2,
 424                         GPOINTER_TO_UINT (g_ptr_array_index (map, i)),
 425                         GPOINTER_TO_UINT (g_ptr_array_index (map, i + 1)));
 426         }
 427 #endif
 428
 429         info->vcall_offset = vcall_offset;
 430         info->map_count = map->len / 2;
 431         for (i = 0; i < map->len; ++i)
 432                 info->map [i] = GPOINTER_TO_UINT (g_ptr_array_index (map, i));
 433         g_ptr_array_free (map, TRUE);
 434
 435         /* Compute return value marshalling */
 436         if (var_ret) {
 437                 /* Compute return value marshalling */
 438                 switch (cinfo->ret.storage) {
 439                 case ArgInIReg:
 440                         if (!gsharedvt_in || sig->ret->byref) {
 441                                 info->ret_marshal = GSHAREDVT_RET_IREGS_1;
 442                         } else {
 443                                 MonoType *ret = sig->ret;
 444
 445                                 // Unwrap enums
 446                                 if (ret->type == MONO_TYPE_VALUETYPE)
 447                                         ret = mini_type_get_underlying_type (ret);
 448
 449                                 switch (ret->type) {
 450                                 case MONO_TYPE_I1:
 451                                         info->ret_marshal = GSHAREDVT_RET_I1;
 452                                         break;
 453                                 case MONO_TYPE_BOOLEAN:
 454                                 case MONO_TYPE_U1:
 455                                         info->ret_marshal = GSHAREDVT_RET_U1;
 456                                         break;
 457                                 case MONO_TYPE_I2:
 458                                         info->ret_marshal = GSHAREDVT_RET_I2;
 459                                         break;
 460                                 case MONO_TYPE_CHAR:
 461                                 case MONO_TYPE_U2:
 462                                         info->ret_marshal = GSHAREDVT_RET_U2;
 463                                         break;
 464                                 case MONO_TYPE_I4:
 465                                         info->ret_marshal = GSHAREDVT_RET_I4;
 466                                         break;
 467                                 case MONO_TYPE_U4:
 468                                         info->ret_marshal = GSHAREDVT_RET_U4;
 469                                         break;
 470                                 case MONO_TYPE_I:
 471                                 case MONO_TYPE_U:
 472                                 case MONO_TYPE_PTR:
 473                                 case MONO_TYPE_FNPTR:
 474                                 case MONO_TYPE_CLASS:
 475                                 case MONO_TYPE_OBJECT:
 476                                 case MONO_TYPE_SZARRAY:
 477                                 case MONO_TYPE_ARRAY:
 478                                 case MONO_TYPE_STRING:
 479                                 case MONO_TYPE_U8:
 480                                 case MONO_TYPE_I8:
 481                                         info->ret_marshal = GSHAREDVT_RET_I8;
 482                                         break;
 483                                 case MONO_TYPE_GENERICINST:
 484                                         g_assert (!mono_type_generic_inst_is_valuetype (ret));
 485                                         info->ret_marshal = GSHAREDVT_RET_I8;
 486                                         break;
 487                                 default:
 488                                         g_error ("Gsharedvt can't handle dst type [%d]", (int)sig->ret->type);
 489                                 }
 490                         }
 491                         break;
 492                 case ArgValuetypeInReg:
 493                         info->ret_marshal = GSHAREDVT_RET_IREGS_1 - 1 + cinfo->ret.nregs;
 494                         g_assert (cinfo->ret.nregs == 1); // ABI supports 2-register return but we do not implement this.
 495                         break;
 496                 case ArgInDoubleSSEReg:
 497                 case ArgInFloatSSEReg:
 498                         info->ret_marshal = GSHAREDVT_RET_R8;
 499                         break;
 500                 case ArgValuetypeAddrInIReg:
 501                         break;
 502                 default:
 503                         g_error ("Can't marshal return of storage [%d] %s", (int)cinfo->ret.storage, storage_name (cinfo->ret.storage));
 504                 }
 505
 506                 if (gsharedvt_in && cinfo->ret.storage != ArgValuetypeAddrInIReg) {
 507                         /* Allocate stack space for the return value */
 508                         info->vret_slot = map_stack_slot (info->stack_usage / sizeof (gpointer));
 509                         info->stack_usage += mono_type_stack_size_internal (normal_sig->ret, NULL, FALSE) + sizeof (gpointer);
 510                 }
 511                 DEBUG_AMD64_GSHAREDVT_PRINT ("RET marshal is %s\n", ret_marshal_name [info->ret_marshal]);
 512         }
 513
 514         info->stack_usage = ALIGN_TO (info->stack_usage, MONO_ARCH_FRAME_ALIGNMENT);
 515
 516         g_free (callee_cinfo);
 517         g_free (caller_cinfo);
 518
 519         DEBUG_AMD64_GSHAREDVT_PRINT ("allocated an info at %p stack usage %d\n", info, info->stack_usage);
 520         return info;
 521 }
 522
 523 #endif