ld/scripttempl/ppcpe.sc

   1 # A PE linker script for PowerPC.
   2 # Loosely based on Steve Chamberlain's pe.sc.
   3 # All new mistakes should be credited to Kim Knuttila (krk@cygnus.com)
   4 #
   5 # Copyright (C) 2014-2018 Free Software Foundation, Inc.
   6 #
   7 # Copying and distribution of this file, with or without modification,
   8 # are permitted in any medium without royalty provided the copyright
   9 # notice and this notice are preserved.
  10 #
  11 # These are substituted in as variables in order to get '}' in a shell
  12 # conditional expansion.
  13
  14 INIT='.init : { *(.init) }'
  15 FINI='.fini : { *(.fini) }'
  16
  17 cat <<EOF
  18 /* Copyright (C) 2014-2018 Free Software Foundation, Inc.
  19
  20    Copying and distribution of this script, with or without modification,
  21    are permitted in any medium without royalty provided the copyright
  22    notice and this notice are preserved.  */
  23
  24 OUTPUT_FORMAT(${OUTPUT_FORMAT})
  25 ${LIB_SEARCH_DIRS}
  26
  27 /* Much of this layout was determined by delving into .exe files for
  28    the box generated by other compilers/linkers/etc. This means that
  29    if a particular feature did not happen to appear in one of the
  30    subject files, then it may not be yet supported.
  31 */
  32
  33 /* It's "mainCRTStartup", not "_mainCRTStartup", and it's located in
  34    one of the two .lib files (libc.lib and kernel32.lib) that currently
  35    must be present on the link line. This means that you must use
  36    "-u mainCRTStartup" to make sure it gets included in the link.
  37 */
  38
  39 ${RELOCATING+ENTRY (mainCRTStartup)}
  40
  41 SECTIONS
  42 {
  43
  44   /* text - the usual meaning */
  45   .text ${RELOCATING+ __image_base__ + __section_alignment__ } :
  46         {
  47             ${RELOCATING+ *(.init);}
  48             *(.text)
  49             ${RELOCATING+ *(.text.*)}
  50             *(.gcc_except_table)
  51             ${CONSTRUCTING+ ___CTOR_LIST__ = .; __CTOR_LIST__ = . ;
  52                         LONG (-1); *(.ctors); *(.ctor); LONG (0); }
  53             ${CONSTRUCTING+ ___DTOR_LIST__ = .; __DTOR_LIST__ = . ;
  54                         LONG (-1); *(.dtors); *(.dtor); LONG (0); }
  55             ${RELOCATING+ *(.fini);}
  56             ${RELOCATING+ etext = .};
  57         }
  58
  59   /* rdata - Read Only Runtime Data
  60      CTR sections: All of the CRT (read only C runtime data) sections
  61         appear at the start of the .rdata (read only runtime data)
  62         section, in the following order. Don't know if it matters or not.
  63         Not all sections are always present either.
  64      .rdata: compiler generated read only data
  65      .xdata: compiler generated exception handling table. (Most docs
  66         seem to suggest that this section is now deprecated infavor
  67         of the ydata section)
  68      .edata: The exported names table.
  69   */
  70   .rdata BLOCK(__section_alignment__) :
  71         {
  72             *(.CRT\$XCA);
  73             *(.CRT\$XCC);
  74             *(.CRT\$XCZ);
  75             *(.CRT\$XIA);
  76             *(.CRT\$XIC);
  77             *(.CRT\$XIZ);
  78             *(.CRT\$XLA);
  79             *(.CRT\$XLZ);
  80             *(.CRT\$XPA);
  81             *(.CRT\$XPX);
  82             *(.CRT\$XPZ);
  83             *(.CRT\$XTA);
  84             *(.CRT\$XTZ);
  85             *(.rdata);
  86             *(.xdata);
  87         }
  88
  89   .edata BLOCK(__section_alignment__) :
  90         {
  91             *(.edata);
  92         }
  93
  94   /* data - initialized data
  95      .ydata: exception handling information.
  96      .data: the usual meaning.
  97      .data2: more of the same.
  98      .bss: For some reason, bss appears to be included in the data
  99         section, as opposed to being given a section of it's own.
 100      COMMON:
 101   */
 102   .data BLOCK(__section_alignment__) :
 103         {
 104             __data_start__ = . ;
 105             *(.ydata);
 106             *(.data);
 107             *(.data2);
 108             __bss_start__ = . ;
 109             *(.bss) ;
 110             *(COMMON);
 111             __bss_end__ = . ;
 112             ${RELOCATING+ end =  .};
 113             __data_end__ = . ;
 114         }
 115
 116   /* The exception handling table. A sequence of 5 word entries. Section
 117      address and extent are placed in the DataDirectory.
 118   */
 119   .pdata BLOCK(__section_alignment__) :
 120         {
 121             *(.pdata)
 122             ;
 123         }
 124
 125   /* The idata section is chock full of magic bits.
 126         1. Boundaries around various idata parts are used to initialize
 127            some of the fields of the DataDirectory. In particular, the
 128            magic for 2, 4 and 5 are known to be used. Some compilers
 129            appear to generate magic section symbols for this purpose.
 130            Where we can, we catch such symbols and use our own. This of
 131            course is something less than a perfect strategy.
 132         2. The table of contents is placed immediately after idata4.
 133            The ".private.toc" sections are generated by the ppc bfd. The
 134            .toc variable is generated by gas, and resolved here. It is
 135            used to initialized function descriptors (and anyone else who
 136            needs the address of the module's toc). The only thing
 137            interesting about it at all? Most ppc instructions using it
 138            have a 16bit displacement field. The convention for addressing
 139            is to initialize the .toc value to 32K past the start of the
 140            actual toc, and subtract 32K from all references, thus using
 141            the entire 64K range. Naturally, the reloc code must agree
 142            on this number or you get pretty stupid results.
 143   */
 144   .idata BLOCK(__section_alignment__) :
 145         {
 146             __idata2_magic__ = .;
 147             *(.idata\$2);
 148             __idata3_magic__ = .;
 149             *(.idata\$3);
 150             __idata4_magic__ = .;
 151             *(.idata\$4);
 152             . = ALIGN(4);
 153             .toc = . + 32768;
 154             *(.private.toc);
 155             __idata5_magic__ = .;
 156             *(.idata\$5);
 157             __idata6_magic__ = .;
 158             *(.idata\$6);
 159             __idata7_magic__ = .;
 160             *(.idata\$7);
 161             ;
 162         }
 163
 164   /* reldata -- data that requires relocation
 165   */
 166   .reldata BLOCK(__section_alignment__) :
 167         {
 168             *(.reldata)
 169             ;
 170         }
 171
 172
 173   /* Resources */
 174   .rsrc BLOCK(__section_alignment__) :
 175         {
 176             *(.rsrc\$01)
 177             *(.rsrc\$02)
 178             ;
 179         }
 180
 181   .stab BLOCK(__section_alignment__)  ${RELOCATING+(NOLOAD)} :
 182   {
 183     [ .stab ]
 184   }
 185
 186   .stabstr BLOCK(__section_alignment__) ${RELOCATING+(NOLOAD)} :
 187   {
 188     [ .stabstr ]
 189   }
 190
 191   /* The .reloc section is currently generated by the dlltool from Steve
 192      Chamberlain in a second pass of linking. Section address and extent
 193      are placed in the DataDirectory.
 194   */
 195   .reloc BLOCK(__section_alignment__) :
 196         {
 197             *(.reloc)
 198             ;
 199         }
 200
 201   /* We don't do anything useful with codeview debugger support or the
 202      directive section (yet). Hopefully, we junk them correctly.
 203   */
 204   /DISCARD/ BLOCK(__section_alignment__) :
 205         {
 206             *(.debug\$S)
 207             *(.debug\$T)
 208             *(.debug\$F)
 209             *(.drectve)
 210             ;
 211         }
 212 }
 213 EOF