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