gcc/config/arm/pe.c

   1 /* Routines for GCC for ARM/pe.
   2    Copyright (C) 1995, 1996, 2000, 2001, 2002, 2004, 2005, 2007, 2008
   3    Free Software Foundation, Inc.
   4    Contributed by Doug Evans (dje@cygnus.com).
   5
   6    This file is part of GCC.
   7
   8    GCC is free software; you can redistribute it and/or modify it
   9    under the terms of the GNU General Public License as published
  10    by the Free Software Foundation; either version 3, or (at your
  11    option) any later version.
  12
  13    GCC is distributed in the hope that it will be useful, but WITHOUT
  14    ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  15    or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public
  16    License for more details.
  17
  18    You should have received a copy of the GNU General Public License
  19    along with GCC; see the file COPYING3.  If not see
  20    <http://www.gnu.org/licenses/>.  */
  21
  22 #include "config.h"
  23 #include "system.h"
  24 #include "coretypes.h"
  25 #include "tm.h"
  26 #include "rtl.h"
  27 #include "output.h"
  28 #include "flags.h"
  29 #include "tree.h"
  30 #include "expr.h"
  31 #include "diagnostic-core.h"
  32 #include "toplev.h"
  33 #include "tm_p.h"
  34
  35 extern int current_function_anonymous_args;
  36
  37 \f
  38 /* Return nonzero if DECL is a dllexport'd object.  */
  39
  40 tree current_class_type; /* FIXME */
  41
  42 int
  43 arm_dllexport_p (tree decl)
  44 {
  45   tree exp;
  46
  47   if (TREE_CODE (decl) != VAR_DECL
  48       && TREE_CODE (decl) != FUNCTION_DECL)
  49     return 0;
  50   exp = lookup_attribute ("dllexport", DECL_ATTRIBUTES (decl));
  51   if (exp)
  52     return 1;
  53
  54   return 0;
  55 }
  56
  57 /* Return nonzero if DECL is a dllimport'd object.  */
  58
  59 int
  60 arm_dllimport_p (tree decl)
  61 {
  62   tree imp;
  63
  64   if (TREE_CODE (decl) == FUNCTION_DECL
  65       && TARGET_NOP_FUN_DLLIMPORT)
  66     return 0;
  67
  68   if (TREE_CODE (decl) != VAR_DECL
  69       && TREE_CODE (decl) != FUNCTION_DECL)
  70     return 0;
  71   imp = lookup_attribute ("dllimport", DECL_ATTRIBUTES (decl));
  72   if (imp)
  73     return 1;
  74
  75   return 0;
  76 }
  77
  78 /* Return nonzero if SYMBOL is marked as being dllexport'd.  */
  79
  80 int
  81 arm_dllexport_name_p (const char *symbol)
  82 {
  83   return symbol[0] == ARM_PE_FLAG_CHAR && symbol[1] == 'e' && symbol[2] == '.';
  84 }
  85
  86 /* Return nonzero if SYMBOL is marked as being dllimport'd.  */
  87
  88 int
  89 arm_dllimport_name_p (const char *symbol)
  90 {
  91   return symbol[0] == ARM_PE_FLAG_CHAR && symbol[1] == 'i' && symbol[2] == '.';
  92 }
  93
  94 /* Mark a DECL as being dllexport'd.
  95    Note that we override the previous setting (e.g.: dllimport).  */
  96
  97 void
  98 arm_mark_dllexport (tree decl)
  99 {
 100   const char * oldname;
 101   char * newname;
 102   rtx rtlname;
 103   tree idp;
 104
 105   rtlname = XEXP (DECL_RTL (decl), 0);
 106   if (GET_CODE (rtlname) == MEM)
 107     rtlname = XEXP (rtlname, 0);
 108   gcc_assert (GET_CODE (rtlname) == SYMBOL_REF);
 109   oldname = XSTR (rtlname, 0);
 110
 111   if (arm_dllimport_name_p (oldname))
 112     oldname += 9;
 113   else if (arm_dllexport_name_p (oldname))
 114     return; /* already done */
 115
 116   newname = XALLOCAVEC (char, strlen (oldname) + 4);
 117   sprintf (newname, "%ce.%s", ARM_PE_FLAG_CHAR, oldname);
 118
 119   /* We pass newname through get_identifier to ensure it has a unique
 120      address.  RTL processing can sometimes peek inside the symbol ref
 121      and compare the string's addresses to see if two symbols are
 122      identical.  */
 123   /* ??? At least I think that's why we do this.  */
 124   idp = get_identifier (newname);
 125
 126   XEXP (DECL_RTL (decl), 0) =
 127     gen_rtx_SYMBOL_REF (Pmode, IDENTIFIER_POINTER (idp));
 128 }
 129
 130 /* Mark a DECL as being dllimport'd.  */
 131
 132 void
 133 arm_mark_dllimport (tree decl)
 134 {
 135   const char * oldname;
 136   char * newname;
 137   tree idp;
 138   rtx rtlname, newrtl;
 139
 140   rtlname = XEXP (DECL_RTL (decl), 0);
 141
 142   if (GET_CODE (rtlname) == MEM)
 143     rtlname = XEXP (rtlname, 0);
 144   gcc_assert (GET_CODE (rtlname) == SYMBOL_REF);
 145   oldname = XSTR (rtlname, 0);
 146
 147   gcc_assert (!arm_dllexport_name_p (oldname));
 148   if (arm_dllimport_name_p (oldname))
 149     return; /* already done */
 150
 151   /* ??? One can well ask why we're making these checks here,
 152      and that would be a good question.  */
 153
 154   /* Imported variables can't be initialized.  */
 155   if (TREE_CODE (decl) == VAR_DECL
 156       && !DECL_VIRTUAL_P (decl)
 157       && DECL_INITIAL (decl))
 158     {
 159       error ("initialized variable %q+D is marked dllimport", decl);
 160       return;
 161     }
 162   /* Nor can they be static.  */
 163   if (TREE_CODE (decl) == VAR_DECL
 164       /* ??? Is this test for vtables needed?  */
 165       && !DECL_VIRTUAL_P (decl)
 166       && 0 /*???*/)
 167     {
 168       error ("static variable %q+D is marked dllimport", decl);
 169       return;
 170     }
 171
 172   /* `extern' needn't be specified with dllimport.
 173      Specify `extern' now and hope for the best.  Sigh.  */
 174   if (TREE_CODE (decl) == VAR_DECL
 175       /* ??? Is this test for vtables needed?  */
 176       && !DECL_VIRTUAL_P (decl))
 177     {
 178       DECL_EXTERNAL (decl) = 1;
 179       TREE_PUBLIC (decl) = 1;
 180     }
 181
 182   newname = XALLOCAVEC (char, strlen (oldname) + 11);
 183   sprintf (newname, "%ci.__imp_%s", ARM_PE_FLAG_CHAR, oldname);
 184
 185   /* We pass newname through get_identifier to ensure it has a unique
 186      address.  RTL processing can sometimes peek inside the symbol ref
 187      and compare the string's addresses to see if two symbols are
 188      identical.  */
 189   /* ??? At least I think that's why we do this.  */
 190   idp = get_identifier (newname);
 191
 192   newrtl = gen_rtx_MEM (Pmode,
 193                         gen_rtx_SYMBOL_REF (Pmode,
 194                                             IDENTIFIER_POINTER (idp)));
 195   XEXP (DECL_RTL (decl), 0) = newrtl;
 196 }
 197
 198 void
 199 arm_pe_encode_section_info (tree decl, rtx rtl, int first ATTRIBUTE_UNUSED)
 200 {
 201   /* This bit is copied from arm_encode_section_info.  */
 202   if (optimize > 0 && TREE_CONSTANT (decl))
 203     SYMBOL_REF_FLAG (XEXP (rtl, 0)) = 1;
 204
 205   /* Mark the decl so we can tell from the rtl whether the object is
 206      dllexport'd or dllimport'd.  */
 207   if (arm_dllexport_p (decl))
 208     arm_mark_dllexport (decl);
 209   else if (arm_dllimport_p (decl))
 210     arm_mark_dllimport (decl);
 211   /* It might be that DECL has already been marked as dllimport, but a
 212      subsequent definition nullified that.  The attribute is gone but
 213      DECL_RTL still has @i.__imp_foo.  We need to remove that.  */
 214   else if ((TREE_CODE (decl) == FUNCTION_DECL
 215             || TREE_CODE (decl) == VAR_DECL)
 216            && DECL_RTL (decl) != NULL_RTX
 217            && GET_CODE (DECL_RTL (decl)) == MEM
 218            && GET_CODE (XEXP (DECL_RTL (decl), 0)) == MEM
 219            && GET_CODE (XEXP (XEXP (DECL_RTL (decl), 0), 0)) == SYMBOL_REF
 220            && arm_dllimport_name_p (XSTR (XEXP (XEXP (DECL_RTL (decl), 0), 0), 0)))
 221     {
 222       const char *oldname = XSTR (XEXP (XEXP (DECL_RTL (decl), 0), 0), 0);
 223       tree idp = get_identifier (oldname + 9);
 224       rtx newrtl = gen_rtx_SYMBOL_REF (Pmode, IDENTIFIER_POINTER (idp));
 225
 226       XEXP (DECL_RTL (decl), 0) = newrtl;
 227
 228       /* We previously set TREE_PUBLIC and DECL_EXTERNAL.
 229          ??? We leave these alone for now.  */
 230     }
 231 }
 232
 233 void
 234 arm_pe_unique_section (tree decl, int reloc)
 235 {
 236   int len;
 237   const char * name;
 238   char * string;
 239   const char * prefix;
 240
 241   name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
 242   name = arm_strip_name_encoding (name);
 243
 244   /* The object is put in, for example, section .text$foo.
 245      The linker will then ultimately place them in .text
 246      (everything from the $ on is stripped).  */
 247   if (TREE_CODE (decl) == FUNCTION_DECL)
 248     prefix = ".text$";
 249   else if (decl_readonly_section (decl, reloc))
 250     prefix = ".rdata$";
 251   else
 252     prefix = ".data$";
 253   len = strlen (name) + strlen (prefix);
 254   string = XALLOCAVEC (char, len + 1);
 255   sprintf (string, "%s%s", prefix, name);
 256
 257   DECL_SECTION_NAME (decl) = build_string (len, string);
 258 }