mono/mini/mini-arm-gsharedvt.c

   1 /**
   2  * \file
   3  * gsharedvt support code for arm
   4  *
   5  * Authors:
   6  *   Zoltan Varga <vargaz@gmail.com>
   7  *
   8  * Copyright 2013 Xamarin, Inc (http://www.xamarin.com)
   9  * Licensed under the MIT license. See LICENSE file in the project root for full license information.
  10  */
  11 #include <config.h>
  12 #include <glib.h>
  13
  14 #include <mono/metadata/abi-details.h>
  15 #include <mono/metadata/appdomain.h>
  16 #include <mono/metadata/marshal.h>
  17 #include <mono/metadata/tabledefs.h>
  18 #include <mono/metadata/profiler-private.h>
  19 #include <mono/arch/arm/arm-codegen.h>
  20 #include <mono/arch/arm/arm-vfp-codegen.h>
  21
  22 #include "mini.h"
  23 #include "mini-arm.h"
  24
  25 #ifdef MONO_ARCH_GSHAREDVT_SUPPORTED
  26
  27 /*
  28  * GSHAREDVT
  29  */
  30
  31 gboolean
  32 mono_arch_gsharedvt_sig_supported (MonoMethodSignature *sig)
  33 {
  34         /*
  35         if (sig->ret && is_variable_size (sig->ret))
  36                 return FALSE;
  37         */
  38         return TRUE;
  39 }
  40
  41 static void
  42 add_to_map (GPtrArray *map, int src, int dst)
  43 {
  44         g_ptr_array_add (map, GUINT_TO_POINTER (src));
  45         g_ptr_array_add (map, GUINT_TO_POINTER (dst));
  46 }
  47
  48 static int
  49 map_reg (int reg)
  50 {
  51         return reg;
  52 }
  53
  54 static int
  55 map_stack_slot (int slot)
  56 {
  57         return slot + 4;
  58 }
  59
  60 static int
  61 get_arg_slots (ArgInfo *ainfo, int **out_slots)
  62 {
  63         int sreg = ainfo->reg;
  64         int sslot = ainfo->offset / 4;
  65         int *src = NULL;
  66         int i, nsrc;
  67
  68         switch (ainfo->storage) {
  69         case RegTypeGeneral:
  70                 nsrc = 1;
  71                 src = g_malloc (nsrc * sizeof (int));
  72                 src [0] = map_reg (sreg);
  73                 break;
  74         case RegTypeIRegPair:
  75                 nsrc = 2;
  76                 src = g_malloc (nsrc * sizeof (int));
  77                 src [0] = map_reg (sreg);
  78                 src [1] = map_reg (sreg + 1);
  79                 break;
  80         case RegTypeStructByVal:
  81                 nsrc = ainfo->struct_size / 4;
  82                 src = g_malloc (nsrc * sizeof (int));
  83                 g_assert (ainfo->size <= nsrc);
  84                 for (i = 0; i < ainfo->size; ++i)
  85                         src [i] = map_reg (sreg + i);
  86                 for (i = ainfo->size; i < nsrc; ++i)
  87                         src [i] = map_stack_slot (sslot + (i - ainfo->size));
  88                 break;
  89         case RegTypeBase:
  90                 nsrc = ainfo->size / 4;
  91                 src = g_malloc (nsrc * sizeof (int));
  92                 for (i = 0; i < nsrc; ++i)
  93                         src [i] = map_stack_slot (sslot + i);
  94                 break;
  95         case RegTypeBaseGen:
  96                 nsrc = 2;
  97                 src = g_malloc (nsrc * sizeof (int));
  98                 src [0] = map_reg (ARMREG_R3);
  99                 src [1] = map_stack_slot (sslot);
 100                 break;
 101         default:
 102                 g_assert_not_reached ();
 103                 break;
 104         }
 105
 106         *out_slots = src;
 107         return nsrc;
 108 }
 109
 110 /*
 111  * mono_arch_get_gsharedvt_call_info:
 112  *
 113  *   See mini-x86.c for documentation.
 114  */
 115 gpointer
 116 mono_arch_get_gsharedvt_call_info (gpointer addr, MonoMethodSignature *normal_sig, MonoMethodSignature *gsharedvt_sig, gboolean gsharedvt_in, gint32 vcall_offset, gboolean calli)
 117 {
 118         GSharedVtCallInfo *info;
 119         CallInfo *caller_cinfo, *callee_cinfo;
 120         MonoMethodSignature *caller_sig, *callee_sig;
 121         int aindex, i;
 122         gboolean var_ret = FALSE;
 123         gboolean have_fregs = FALSE;
 124         CallInfo *cinfo, *gcinfo;
 125         MonoMethodSignature *sig, *gsig;
 126         GPtrArray *map;
 127
 128         if (gsharedvt_in) {
 129                 caller_sig = normal_sig;
 130                 callee_sig = gsharedvt_sig;
 131                 caller_cinfo = mono_arch_get_call_info (NULL, caller_sig);
 132                 callee_cinfo = mono_arch_get_call_info (NULL, callee_sig);
 133         } else {
 134                 callee_sig = normal_sig;
 135                 callee_cinfo = mono_arch_get_call_info (NULL, callee_sig);
 136                 caller_sig = gsharedvt_sig;
 137                 caller_cinfo = mono_arch_get_call_info (NULL, caller_sig);
 138         }
 139
 140         /*
 141          * If GSHAREDVT_IN is true, this means we are transitioning from normal to gsharedvt code. The caller uses the
 142          * normal call signature, while the callee uses the gsharedvt signature.
 143          * If GSHAREDVT_IN is false, its the other way around.
 144          */
 145
 146         /* sig/cinfo describes the normal call, while gsig/gcinfo describes the gsharedvt call */
 147         if (gsharedvt_in) {
 148                 sig = caller_sig;
 149                 gsig = callee_sig;
 150                 cinfo = caller_cinfo;
 151                 gcinfo = callee_cinfo;
 152         } else {
 153                 sig = callee_sig;
 154                 gsig = caller_sig;
 155                 cinfo = callee_cinfo;
 156                 gcinfo = caller_cinfo;
 157         }
 158
 159         if (gcinfo->ret.storage == RegTypeStructByAddr && gsig->ret && mini_is_gsharedvt_type (gsig->ret)) {
 160                 /*
 161                  * The return type is gsharedvt
 162                  */
 163                 var_ret = TRUE;
 164         }
 165
 166         /*
 167          * The stack looks like this:
 168          * <arguments>
 169          * <ret addr>
 170          * <saved ebp>
 171          * <call area>
 172          * We have to map the stack slots in <arguments> to the stack slots in <call area>.
 173          * The argument registers are mapped to slot 0..3, stack slot 0 is mapped to slot 4, etc.
 174          */
 175         map = g_ptr_array_new ();
 176
 177         if (cinfo->ret.storage == RegTypeStructByAddr) {
 178                 /*
 179                  * Map ret arg.
 180                  * This handles the case when the method returns a normal vtype, and when it returns a type arg, and its instantiated
 181                  * with a vtype.
 182                  */
 183                 g_assert (caller_cinfo->ret.storage == RegTypeStructByAddr);
 184                 g_assert (callee_cinfo->ret.storage == RegTypeStructByAddr);
 185                 add_to_map (map, map_reg (caller_cinfo->ret.reg), map_reg (callee_cinfo->ret.reg));
 186         }
 187
 188         for (aindex = 0; aindex < cinfo->nargs; ++aindex) {
 189                 ArgInfo *ainfo = &caller_cinfo->args [aindex];
 190                 ArgInfo *ainfo2 = &callee_cinfo->args [aindex];
 191                 int *src = NULL, *dst = NULL;
 192                 int nsrc, ndst, nslots, src_slot, arg_marshal;
 193
 194                 if (ainfo->storage == RegTypeFP || ainfo2->storage == RegTypeFP) {
 195                         have_fregs = TRUE;
 196                         continue;
 197                 }
 198
 199                 /*
 200                  * The src descriptor looks like this:
 201                  * - 4 bits src slot
 202                  * - 12 bits number of slots
 203                  * - 8 bits marshal type (GSHAREDVT_ARG_...)
 204                  */
 205
 206                 arg_marshal = GSHAREDVT_ARG_NONE;
 207
 208                 if (ainfo->storage == RegTypeGSharedVtInReg || ainfo->storage == RegTypeGSharedVtOnStack) {
 209                         /* Pass the value whose address is received in a reg by value */
 210                         g_assert (ainfo2->storage != RegTypeGSharedVtInReg);
 211                         ndst = get_arg_slots (ainfo2, &dst);
 212                         nsrc = 1;
 213                         src = g_new0 (int, 1);
 214                         if (ainfo->storage == RegTypeGSharedVtInReg)
 215                                 src_slot = map_reg (ainfo->reg);
 216                         else
 217                                 src_slot = map_stack_slot (ainfo->offset / sizeof (target_mgreg_t));
 218                         g_assert (ndst < 256);
 219                         g_assert (src_slot < 256);
 220                         src [0] = (ndst << 8) | src_slot;
 221
 222                         if (ainfo2->storage == RegTypeGeneral && ainfo2->size != 0 && ainfo2->size != sizeof (target_mgreg_t)) {
 223                                 /* Have to load less than 4 bytes */
 224                                 switch (ainfo2->size) {
 225                                 case 1:
 226                                         arg_marshal = ainfo2->is_signed ? GSHAREDVT_ARG_BYREF_TO_BYVAL_I1 : GSHAREDVT_ARG_BYREF_TO_BYVAL_U1;
 227                                         break;
 228                                 case 2:
 229                                         arg_marshal = ainfo2->is_signed ? GSHAREDVT_ARG_BYREF_TO_BYVAL_I2 : GSHAREDVT_ARG_BYREF_TO_BYVAL_U2;
 230                                         break;
 231                                 default:
 232                                         g_assert_not_reached ();
 233                                         break;
 234                                 }
 235                         } else {
 236                                 arg_marshal = GSHAREDVT_ARG_BYREF_TO_BYVAL;
 237                         }
 238                 } else {
 239                         nsrc = get_arg_slots (ainfo, &src);
 240                 }
 241                 if (ainfo2->storage == RegTypeGSharedVtInReg) {
 242                         /* Pass the address of the first src slot in a reg */
 243                         arg_marshal = GSHAREDVT_ARG_BYVAL_TO_BYREF;
 244                         ndst = 1;
 245                         dst = g_new0 (int, 1);
 246                         dst [0] = map_reg (ainfo2->reg);
 247                 } else if (ainfo2->storage == RegTypeGSharedVtOnStack) {
 248                         /* Pass the address of the first src slot in a stack slot */
 249                         arg_marshal = GSHAREDVT_ARG_BYVAL_TO_BYREF;
 250                         ndst = 1;
 251                         dst = g_new0 (int, 1);
 252                         dst [0] = map_stack_slot (ainfo2->offset / sizeof (target_mgreg_t));
 253                 } else {
 254                         ndst = get_arg_slots (ainfo2, &dst);
 255                 }
 256                 if (nsrc)
 257                         src [0] |= (arg_marshal << 24);
 258                 nslots = MIN (nsrc, ndst);
 259
 260                 for (i = 0; i < nslots; ++i)
 261                         add_to_map (map, src [i], dst [i]);
 262
 263                 g_free (src);
 264                 g_free (dst);
 265         }
 266
 267         info = mono_domain_alloc0 (mono_domain_get (), sizeof (GSharedVtCallInfo) + (map->len * sizeof (int)));
 268         info->addr = addr;
 269         info->stack_usage = callee_cinfo->stack_usage;
 270         info->ret_marshal = GSHAREDVT_RET_NONE;
 271         info->gsharedvt_in = gsharedvt_in ? 1 : 0;
 272         info->vret_slot = -1;
 273         info->calli = calli;
 274         if (var_ret) {
 275                 g_assert (gcinfo->ret.storage == RegTypeStructByAddr);
 276                 info->vret_arg_reg = gcinfo->ret.reg;
 277         } else {
 278                 info->vret_arg_reg = -1;
 279         }
 280         info->vcall_offset = vcall_offset;
 281         info->map_count = map->len / 2;
 282         for (i = 0; i < map->len; ++i)
 283                 info->map [i] = GPOINTER_TO_UINT (g_ptr_array_index (map, i));
 284         g_ptr_array_free (map, TRUE);
 285
 286         /* Compute return value marshalling */
 287         if (var_ret) {
 288                 switch (cinfo->ret.storage) {
 289                 case RegTypeGeneral:
 290                         if (gsharedvt_in && !sig->ret->byref && sig->ret->type == MONO_TYPE_I1)
 291                                 info->ret_marshal = GSHAREDVT_RET_I1;
 292                         else if (gsharedvt_in && !sig->ret->byref && (sig->ret->type == MONO_TYPE_U1 || sig->ret->type == MONO_TYPE_BOOLEAN))
 293                                 info->ret_marshal = GSHAREDVT_RET_U1;
 294                         else if (gsharedvt_in && !sig->ret->byref && sig->ret->type == MONO_TYPE_I2)
 295                                 info->ret_marshal = GSHAREDVT_RET_I2;
 296                         else if (gsharedvt_in && !sig->ret->byref && (sig->ret->type == MONO_TYPE_U2 || sig->ret->type == MONO_TYPE_CHAR))
 297                                 info->ret_marshal = GSHAREDVT_RET_U2;
 298                         else
 299                                 info->ret_marshal = GSHAREDVT_RET_IREG;
 300                         break;
 301                 case RegTypeIRegPair:
 302                         info->ret_marshal = GSHAREDVT_RET_IREGS;
 303                         break;
 304                 case RegTypeFP:
 305                         if (mono_arm_is_hard_float ()) {
 306                                 if (cinfo->ret.size == 4)
 307                                         info->ret_marshal = GSHAREDVT_RET_VFP_R4;
 308                                 else
 309                                         info->ret_marshal = GSHAREDVT_RET_VFP_R8;
 310                         } else {
 311                                 if (cinfo->ret.size == sizeof (target_mgreg_t))
 312                                         info->ret_marshal = GSHAREDVT_RET_IREG;
 313                                 else
 314                                         info->ret_marshal = GSHAREDVT_RET_IREGS;
 315                         }
 316                         break;
 317                 case RegTypeStructByAddr:
 318                         info->ret_marshal = GSHAREDVT_RET_NONE;
 319                         break;
 320                 default:
 321                         g_assert_not_reached ();
 322                 }
 323         }
 324
 325         if (gsharedvt_in && var_ret && caller_cinfo->ret.storage != RegTypeStructByAddr) {
 326                 /* Allocate stack space for the return value */
 327                 info->vret_slot = map_stack_slot (info->stack_usage / sizeof (target_mgreg_t));
 328                 info->stack_usage += mono_type_stack_size_internal (normal_sig->ret, NULL, FALSE) + sizeof (target_mgreg_t);
 329         }
 330
 331         info->stack_usage = ALIGN_TO (info->stack_usage, MONO_ARCH_FRAME_ALIGNMENT);
 332         info->caller_cinfo = caller_cinfo;
 333         info->callee_cinfo = callee_cinfo;
 334         info->have_fregs = have_fregs;
 335
 336         return info;
 337 }
 338
 339 #endif