gcc/config/arm/pe.c

   1 /* Routines for GCC for ARM/pe.
   2    Copyright (C) 1995, 1996, 2000, 2001 Free Software Foundation, Inc.
   3    Contributed by Doug Evans (dje@cygnus.com).
   4
   5 This file is part of GNU CC.
   6
   7 GNU CC is free software; you can redistribute it and/or modify
   8 it under the terms of the GNU General Public License as published by
   9 the Free Software Foundation; either version 2, or (at your option)
  10 any later version.
  11
  12 GNU CC is distributed in the hope that it will be useful,
  13 but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 GNU General Public License for more details.
  16
  17 You should have received a copy of the GNU General Public License
  18 along with GNU CC; see the file COPYING.  If not, write to
  19 the Free Software Foundation, 59 Temple Place - Suite 330,
  20 Boston, MA 02111-1307, USA.  */
  21
  22 #include "config.h"
  23 #include "system.h"
  24 #include "rtl.h"
  25 #include "output.h"
  26 #include "flags.h"
  27 #include "tree.h"
  28 #include "expr.h"
  29 #include "toplev.h"
  30 #include "tm_p.h"
  31
  32 extern int current_function_anonymous_args;
  33
  34 \f
  35 /* Return non-zero if DECL is a dllexport'd object.  */
  36
  37 tree current_class_type; /* FIXME */
  38
  39 int
  40 arm_dllexport_p (decl)
  41      tree decl;
  42 {
  43   tree exp;
  44
  45   if (TREE_CODE (decl) != VAR_DECL
  46       && TREE_CODE (decl) != FUNCTION_DECL)
  47     return 0;
  48   exp = lookup_attribute ("dllexport", DECL_ATTRIBUTES (decl));
  49   if (exp)
  50     return 1;
  51
  52   return 0;
  53 }
  54
  55 /* Return non-zero if DECL is a dllimport'd object.  */
  56
  57 int
  58 arm_dllimport_p (decl)
  59      tree decl;
  60 {
  61   tree imp;
  62
  63   if (TREE_CODE (decl) == FUNCTION_DECL
  64       && TARGET_NOP_FUN_DLLIMPORT)
  65     return 0;
  66
  67   if (TREE_CODE (decl) != VAR_DECL
  68       && TREE_CODE (decl) != FUNCTION_DECL)
  69     return 0;
  70   imp = lookup_attribute ("dllimport", DECL_ATTRIBUTES (decl));
  71   if (imp)
  72     return 1;
  73
  74   return 0;
  75 }
  76
  77 /* Return non-zero if SYMBOL is marked as being dllexport'd.  */
  78
  79 int
  80 arm_dllexport_name_p (symbol)
  81      const char * symbol;
  82 {
  83   return symbol[0] == ARM_PE_FLAG_CHAR && symbol[1] == 'e' && symbol[2] == '.';
  84 }
  85
  86 /* Return non-zero if SYMBOL is marked as being dllimport'd.  */
  87
  88 int
  89 arm_dllimport_name_p (symbol)
  90      const char * symbol;
  91 {
  92   return symbol[0] == ARM_PE_FLAG_CHAR && symbol[1] == 'i' && symbol[2] == '.';
  93 }
  94
  95 /* Mark a DECL as being dllexport'd.
  96    Note that we override the previous setting (eg: dllimport).  */
  97
  98 void
  99 arm_mark_dllexport (decl)
 100      tree decl;
 101 {
 102   const char * oldname;
 103   char * newname;
 104   rtx rtlname;
 105   tree idp;
 106
 107   rtlname = XEXP (DECL_RTL (decl), 0);
 108   if (GET_CODE (rtlname) == SYMBOL_REF)
 109     oldname = XSTR (rtlname, 0);
 110   else if (GET_CODE (rtlname) == MEM
 111            && GET_CODE (XEXP (rtlname, 0)) == SYMBOL_REF)
 112     oldname = XSTR (XEXP (rtlname, 0), 0);
 113   else
 114     abort ();
 115   if (arm_dllimport_name_p (oldname))
 116     oldname += 9;
 117   else if (arm_dllexport_name_p (oldname))
 118     return; /* already done */
 119
 120   newname = alloca (strlen (oldname) + 4);
 121   sprintf (newname, "%ce.%s", ARM_PE_FLAG_CHAR, oldname);
 122
 123   /* We pass newname through get_identifier to ensure it has a unique
 124      address.  RTL processing can sometimes peek inside the symbol ref
 125      and compare the string's addresses to see if two symbols are
 126      identical.  */
 127   /* ??? At least I think that's why we do this.  */
 128   idp = get_identifier (newname);
 129
 130   XEXP (DECL_RTL (decl), 0) =
 131     gen_rtx (SYMBOL_REF, Pmode, IDENTIFIER_POINTER (idp));
 132 }
 133
 134 /* Mark a DECL as being dllimport'd.  */
 135
 136 void
 137 arm_mark_dllimport (decl)
 138      tree decl;
 139 {
 140   const char * oldname;
 141   char * newname;
 142   tree idp;
 143   rtx rtlname, newrtl;
 144
 145   rtlname = XEXP (DECL_RTL (decl), 0);
 146
 147   if (GET_CODE (rtlname) == SYMBOL_REF)
 148     oldname = XSTR (rtlname, 0);
 149   else if (GET_CODE (rtlname) == MEM
 150            && GET_CODE (XEXP (rtlname, 0)) == SYMBOL_REF)
 151     oldname = XSTR (XEXP (rtlname, 0), 0);
 152   else
 153     abort ();
 154
 155   if (arm_dllexport_name_p (oldname))
 156     abort (); /* this shouldn't happen */
 157   else if (arm_dllimport_name_p (oldname))
 158     return; /* already done */
 159
 160   /* ??? One can well ask why we're making these checks here,
 161      and that would be a good question.  */
 162
 163   /* Imported variables can't be initialized.  */
 164   if (TREE_CODE (decl) == VAR_DECL
 165       && !DECL_VIRTUAL_P (decl)
 166       && DECL_INITIAL (decl))
 167     {
 168       error_with_decl (decl, "initialized variable `%s' is marked dllimport");
 169       return;
 170     }
 171   /* Nor can they be static.  */
 172   if (TREE_CODE (decl) == VAR_DECL
 173       /* ??? Is this test for vtables needed?  */
 174       && !DECL_VIRTUAL_P (decl)
 175       && 0 /*???*/)
 176     {
 177       error_with_decl (decl, "static variable `%s' is marked dllimport");
 178       return;
 179     }
 180
 181   /* `extern' needn't be specified with dllimport.
 182      Specify `extern' now and hope for the best.  Sigh.  */
 183   if (TREE_CODE (decl) == VAR_DECL
 184       /* ??? Is this test for vtables needed?  */
 185       && !DECL_VIRTUAL_P (decl))
 186     {
 187       DECL_EXTERNAL (decl) = 1;
 188       TREE_PUBLIC (decl) = 1;
 189     }
 190
 191   newname = alloca (strlen (oldname) + 11);
 192   sprintf (newname, "%ci.__imp_%s", ARM_PE_FLAG_CHAR, oldname);
 193
 194   /* We pass newname through get_identifier to ensure it has a unique
 195      address.  RTL processing can sometimes peek inside the symbol ref
 196      and compare the string's addresses to see if two symbols are
 197      identical.  */
 198   /* ??? At least I think that's why we do this.  */
 199   idp = get_identifier (newname);
 200
 201   newrtl = gen_rtx (MEM, Pmode,
 202                     gen_rtx (SYMBOL_REF, Pmode,
 203                              IDENTIFIER_POINTER (idp)));
 204   XEXP (DECL_RTL (decl), 0) = newrtl;
 205 }
 206
 207 /* Cover function to implement ENCODE_SECTION_INFO.  */
 208
 209 void
 210 arm_pe_encode_section_info (decl)
 211      tree decl;
 212 {
 213   /* This bit is copied from arm.h.  */
 214   if (optimize > 0 && TREE_CONSTANT (decl)
 215       && (!flag_writable_strings || TREE_CODE (decl) != STRING_CST))
 216     {
 217       rtx rtl = (TREE_CODE_CLASS (TREE_CODE (decl)) != 'd'
 218                  ? TREE_CST_RTL (decl) : DECL_RTL (decl));
 219       SYMBOL_REF_FLAG (XEXP (rtl, 0)) = 1;
 220     }
 221
 222   /* Mark the decl so we can tell from the rtl whether the object is
 223      dllexport'd or dllimport'd.  */
 224   if (arm_dllexport_p (decl))
 225     arm_mark_dllexport (decl);
 226   else if (arm_dllimport_p (decl))
 227     arm_mark_dllimport (decl);
 228   /* It might be that DECL has already been marked as dllimport, but a
 229      subsequent definition nullified that.  The attribute is gone but
 230      DECL_RTL still has @i.__imp_foo.  We need to remove that.  */
 231   else if ((TREE_CODE (decl) == FUNCTION_DECL
 232             || TREE_CODE (decl) == VAR_DECL)
 233            && DECL_RTL (decl) != NULL_RTX
 234            && GET_CODE (DECL_RTL (decl)) == MEM
 235            && GET_CODE (XEXP (DECL_RTL (decl), 0)) == MEM
 236            && GET_CODE (XEXP (XEXP (DECL_RTL (decl), 0), 0)) == SYMBOL_REF
 237            && arm_dllimport_name_p (XSTR (XEXP (XEXP (DECL_RTL (decl), 0), 0), 0)))
 238     {
 239       const char *oldname = XSTR (XEXP (XEXP (DECL_RTL (decl), 0), 0), 0);
 240       tree idp = get_identifier (oldname + 9);
 241       rtx newrtl = gen_rtx (SYMBOL_REF, Pmode, IDENTIFIER_POINTER (idp));
 242
 243       XEXP (DECL_RTL (decl), 0) = newrtl;
 244
 245       /* We previously set TREE_PUBLIC and DECL_EXTERNAL.
 246          ??? We leave these alone for now.  */
 247     }
 248 }
 249
 250 /* Cover function for UNIQUE_SECTION.  */
 251
 252 void
 253 arm_pe_unique_section (decl, reloc)
 254      tree decl;
 255      int reloc;
 256 {
 257   int len;
 258   const char * name;
 259   char * string;
 260   char * prefix;
 261
 262   name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
 263   /* Strip off any encoding in fnname.  */
 264   STRIP_NAME_ENCODING (name, name);
 265
 266   /* The object is put in, for example, section .text$foo.
 267      The linker will then ultimately place them in .text
 268      (everything from the $ on is stripped).  */
 269   if (TREE_CODE (decl) == FUNCTION_DECL)
 270     prefix = ".text$";
 271   else if (DECL_READONLY_SECTION (decl, reloc))
 272     prefix = ".rdata$";
 273   else
 274     prefix = ".data$";
 275   len = strlen (name) + strlen (prefix);
 276   string = alloca (len + 1);
 277   sprintf (string, "%s%s", prefix, name);
 278
 279   DECL_SECTION_NAME (decl) = build_string (len, string);
 280 }