mono/mini/mini-x86-gsharedvt.c

   1 /*
   2  * mini-x86-gsharedvt.c: gsharedvt support code for x86
   3  *
   4  * Authors:
   5  *   Zoltan Varga <vargaz@gmail.com>
   6  *
   7  * Copyright 2013 Xamarin, Inc (http://www.xamarin.com)
   8  * Licensed under the MIT license. See LICENSE file in the project root for full license information.
   9  */
  10 #include "mini.h"
  11
  12 #ifdef MONO_ARCH_GSHAREDVT_SUPPORTED
  13
  14 #define ALIGN_TO(val,align) ((((guint64)val) + ((align) - 1)) & ~((align) - 1))
  15
  16 /*
  17  * GSHAREDVT
  18  */
  19
  20 gboolean
  21 mono_arch_gsharedvt_sig_supported (MonoMethodSignature *sig)
  22 {
  23         /*
  24         if (sig->ret && is_variable_size (sig->ret))
  25                 return FALSE;
  26         */
  27         return TRUE;
  28 }
  29
  30 /*
  31  * mono_arch_get_gsharedvt_call_info:
  32  *
  33  *   Compute calling convention information for marshalling a call between NORMAL_SIG and GSHAREDVT_SIG.
  34  * If GSHAREDVT_IN is TRUE, then the caller calls using the signature NORMAL_SIG but the call is received by
  35  * a method with signature GSHAREDVT_SIG, otherwise its the other way around.
  36  */
  37 gpointer
  38 mono_arch_get_gsharedvt_call_info (gpointer addr, MonoMethodSignature *normal_sig, MonoMethodSignature *gsharedvt_sig, gboolean gsharedvt_in, gint32 vcall_offset, gboolean calli)
  39 {
  40         GSharedVtCallInfo *info;
  41         CallInfo *caller_cinfo, *callee_cinfo;
  42         MonoMethodSignature *caller_sig, *callee_sig;
  43         int i, j;
  44         gboolean var_ret = FALSE;
  45         CallInfo *cinfo, *gcinfo;
  46         MonoMethodSignature *sig, *gsig;
  47         GPtrArray *map;
  48
  49         if (gsharedvt_in) {
  50                 caller_sig = normal_sig;
  51                 callee_sig = gsharedvt_sig;
  52                 caller_cinfo = mono_arch_get_call_info (NULL, caller_sig);
  53                 callee_cinfo = mono_arch_get_call_info (NULL, callee_sig);
  54         } else {
  55                 callee_sig = normal_sig;
  56                 callee_cinfo = mono_arch_get_call_info (NULL, callee_sig);
  57                 caller_sig = gsharedvt_sig;
  58                 caller_cinfo = mono_arch_get_call_info (NULL, caller_sig);
  59         }
  60
  61         /*
  62          * If GSHAREDVT_IN is true, this means we are transitioning from normal to gsharedvt code. The caller uses the
  63          * normal call signature, while the callee uses the gsharedvt signature.
  64          * If GSHAREDVT_IN is false, its the other way around.
  65          */
  66
  67         /* sig/cinfo describes the normal call, while gsig/gcinfo describes the gsharedvt call */
  68         if (gsharedvt_in) {
  69                 sig = caller_sig;
  70                 gsig = callee_sig;
  71                 cinfo = caller_cinfo;
  72                 gcinfo = callee_cinfo;
  73         } else {
  74                 sig = callee_sig;
  75                 gsig = caller_sig;
  76                 cinfo = callee_cinfo;
  77                 gcinfo = caller_cinfo;
  78         }
  79
  80         if (gcinfo->vtype_retaddr && gsig->ret && mini_is_gsharedvt_type (gsig->ret)) {
  81                 /*
  82                  * The return type is gsharedvt
  83                  */
  84                 var_ret = TRUE;
  85         }
  86
  87         /*
  88          * The stack looks like this:
  89          * <arguments>
  90          * <ret addr>
  91          * <saved ebp>
  92          * <call area>
  93          * We have to map the stack slots in <arguments> to the stack slots in <call area>.
  94          */
  95         map = g_ptr_array_new ();
  96
  97         if (cinfo->vtype_retaddr) {
  98                 /*
  99                  * Map ret arg.
 100                  * This handles the case when the method returns a normal vtype, and when it returns a type arg, and its instantiated
 101                  * with a vtype.
 102                  */
 103                 g_ptr_array_add (map, GUINT_TO_POINTER (caller_cinfo->vret_arg_offset / sizeof (gpointer)));
 104                 g_ptr_array_add (map, GUINT_TO_POINTER (callee_cinfo->vret_arg_offset / sizeof (gpointer)));
 105         }
 106
 107         for (i = 0; i < cinfo->nargs; ++i) {
 108                 ArgInfo *ainfo = &caller_cinfo->args [i];
 109                 ArgInfo *ainfo2 = &callee_cinfo->args [i];
 110                 int nslots;
 111
 112                 switch (ainfo->storage) {
 113                 case ArgGSharedVt:
 114                         if (ainfo2->storage == ArgOnStack) {
 115                                 nslots = callee_cinfo->args [i].nslots;
 116                                 if (!nslots)
 117                                         nslots = 1;
 118                                 g_ptr_array_add (map, GUINT_TO_POINTER ((ainfo->offset / sizeof (gpointer)) + (1 << 16) + (nslots << 18)));
 119                                 g_ptr_array_add (map, GUINT_TO_POINTER ((ainfo2->offset / sizeof (gpointer))));
 120                         } else {
 121                                 g_ptr_array_add (map, GUINT_TO_POINTER ((ainfo->offset / sizeof (gpointer))));
 122                                 g_ptr_array_add (map, GUINT_TO_POINTER ((ainfo2->offset / sizeof (gpointer))));
 123                         }
 124                         break;
 125                 default:
 126                         if (ainfo2->storage == ArgOnStack) {
 127                                 nslots = cinfo->args [i].nslots;
 128                                 if (!nslots)
 129                                         nslots = 1;
 130                                 for (j = 0; j < nslots; ++j) {
 131                                         g_ptr_array_add (map, GUINT_TO_POINTER ((ainfo->offset / sizeof (gpointer)) + j));
 132                                         g_ptr_array_add (map, GUINT_TO_POINTER ((ainfo2->offset / sizeof (gpointer)) + j));
 133                                 }
 134                         } else {
 135                                 g_assert (ainfo2->storage == ArgGSharedVt);
 136                                 g_ptr_array_add (map, GUINT_TO_POINTER ((ainfo->offset / sizeof (gpointer)) + (2 << 16)));
 137                                 g_ptr_array_add (map, GUINT_TO_POINTER ((ainfo2->offset / sizeof (gpointer))));
 138                         }
 139                         break;
 140                 }
 141         }
 142
 143         info = mono_domain_alloc0 (mono_domain_get (), sizeof (GSharedVtCallInfo) + (map->len * sizeof (int)));
 144         info->addr = addr;
 145         info->stack_usage = callee_cinfo->stack_usage;
 146         info->ret_marshal = GSHAREDVT_RET_NONE;
 147         info->gsharedvt_in = gsharedvt_in ? 1 : 0;
 148         info->vret_slot = -1;
 149         info->calli = calli ? 1 : 0;
 150         if (var_ret)
 151                 info->vret_arg_slot = gcinfo->vret_arg_offset / sizeof (gpointer);
 152         else
 153                 info->vret_arg_slot = -1;
 154         info->vcall_offset = vcall_offset;
 155         info->map_count = map->len / 2;
 156         for (i = 0; i < map->len; ++i)
 157                 info->map [i] = GPOINTER_TO_UINT (g_ptr_array_index (map, i));
 158         g_ptr_array_free (map, TRUE);
 159
 160         /* Compute return value marshalling */
 161         if (var_ret) {
 162                 switch (cinfo->ret.storage) {
 163                 case ArgInIReg:
 164                         if (gsharedvt_in && !sig->ret->byref && sig->ret->type == MONO_TYPE_I1)
 165                                 info->ret_marshal = GSHAREDVT_RET_I1;
 166                         else if (gsharedvt_in && !sig->ret->byref && (sig->ret->type == MONO_TYPE_U1 || sig->ret->type == MONO_TYPE_BOOLEAN))
 167                                 info->ret_marshal = GSHAREDVT_RET_U1;
 168                         else if (gsharedvt_in && !sig->ret->byref && sig->ret->type == MONO_TYPE_I2)
 169                                 info->ret_marshal = GSHAREDVT_RET_I2;
 170                         else if (gsharedvt_in && !sig->ret->byref && (sig->ret->type == MONO_TYPE_U2 || sig->ret->type == MONO_TYPE_CHAR))
 171                                 info->ret_marshal = GSHAREDVT_RET_U2;
 172                         else if (cinfo->ret.is_pair)
 173                                 info->ret_marshal = GSHAREDVT_RET_IREGS;
 174                         else
 175                                 info->ret_marshal = GSHAREDVT_RET_IREG;
 176                         break;
 177                 case ArgOnDoubleFpStack:
 178                         info->ret_marshal = GSHAREDVT_RET_DOUBLE_FPSTACK;
 179                         break;
 180                 case ArgOnFloatFpStack:
 181                         info->ret_marshal = GSHAREDVT_RET_FLOAT_FPSTACK;
 182                         break;
 183                 case ArgOnStack:
 184                         /* The caller passes in a vtype ret arg as well */
 185                         g_assert (gcinfo->vtype_retaddr);
 186                         /* Just have to pop the arg, as done by normal methods in their epilog */
 187                         info->ret_marshal = GSHAREDVT_RET_STACK_POP;
 188                         break;
 189                 default:
 190                         g_assert_not_reached ();
 191                 }
 192         } else if (gsharedvt_in && cinfo->vtype_retaddr) {
 193                 info->ret_marshal = GSHAREDVT_RET_STACK_POP;
 194         }
 195
 196         if (gsharedvt_in && var_ret && !caller_cinfo->vtype_retaddr) {
 197                 /* Allocate stack space for the return value */
 198                 info->vret_slot = info->stack_usage / sizeof (gpointer);
 199                 // FIXME:
 200                 info->stack_usage += sizeof (gpointer) * 3;
 201         }
 202
 203         info->stack_usage = ALIGN_TO (info->stack_usage, MONO_ARCH_FRAME_ALIGNMENT);
 204
 205         g_free (caller_cinfo);
 206         g_free (callee_cinfo);
 207
 208         return info;
 209 }
 210 #endif