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 # These are substituted in as variables in order to get '}' in a shell
   6 # conditional expansion.
   7 INIT='.init : { *(.init) }'
   8 FINI='.fini : { *(.fini) }'
   9 cat <<EOF
  10 OUTPUT_FORMAT(${OUTPUT_FORMAT})
  11 ${LIB_SEARCH_DIRS}
  12
  13 /* Much of this layout was determined by delving into .exe files for
  14    the box generated by other compilers/linkers/etc. This means that
  15    if a particular feature did not happen to appear in one of the
  16    subject files, then it may not be yet supported.
  17 */
  18
  19 /* It's "mainCRTStartup", not "_mainCRTStartup", and it's located in
  20    one of the two .lib files (libc.lib and kernel32.lib) that currently
  21    must be present on the link line. This means that you must use
  22    "-u mainCRTStartup" to make sure it gets included in the link.
  23 */
  24
  25 ENTRY(mainCRTStartup)
  26
  27 SECTIONS
  28 {
  29
  30   /* text - the usual meaning */
  31   .text ${RELOCATING+ __image_base__ + __section_alignment__ } :
  32         {
  33             ${RELOCATING+ *(.init);}
  34             *(.text)
  35             *(.gcc_except_table)
  36             ${CONSTRUCTING+ ___CTOR_LIST__ = .; __CTOR_LIST__ = . ;
  37                         LONG (-1); *(.ctors); *(.ctor); LONG (0); }
  38             ${CONSTRUCTING+ ___DTOR_LIST__ = .; __DTOR_LIST__ = . ;
  39                         LONG (-1); *(.dtors); *(.dtor);  LONG (0); }
  40             ${RELOCATING+ *(.fini);}
  41             ${RELOCATING+ etext  =  .};
  42         }
  43
  44   /* rdata - Read Only Runtime Data
  45      CTR sections: All of the CRT (read only C runtime data) sections
  46         appear at the start of the .rdata (read only runtime data)
  47         section, in the following order. Don't know if it matters or not.
  48         Not all sections are always present either.
  49      .rdata: compiler generated read only data
  50      .xdata: compiler generated exception handling table. (Most docs
  51         seem to suggest that this section is now deprecated infavor
  52         of the ydata section)
  53      .edata: The exported names table.
  54   */
  55   .rdata BLOCK(__section_alignment__) :
  56         {
  57             *(.CRT\$XCA);
  58             *(.CRT\$XCC);
  59             *(.CRT\$XCZ);
  60             *(.CRT\$XIA);
  61             *(.CRT\$XIC);
  62             *(.CRT\$XIZ);
  63             *(.CRT\$XLA);
  64             *(.CRT\$XLZ);
  65             *(.CRT\$XPA);
  66             *(.CRT\$XPX);
  67             *(.CRT\$XPZ);
  68             *(.CRT\$XTA);
  69             *(.CRT\$XTZ);
  70             *(.rdata);
  71             *(.xdata);
  72         }
  73
  74   .edata BLOCK(__section_alignment__) :
  75         {
  76             *(.edata);
  77         }
  78
  79   /* data - initialized data
  80      .ydata: exception handling information.
  81      .data: the usual meaning.
  82      .data2: more of the same.
  83      .bss: For some reason, bss appears to be included in the data
  84         section, as opposed to being given a section of it's own.
  85      COMMON:
  86   */
  87   .data BLOCK(__section_alignment__) :
  88         {
  89             __data_start__ = . ;
  90             *(.ydata);
  91             *(.data);
  92             *(.data2);
  93             __bss_start__ = . ;
  94             *(.bss) ;
  95             *(COMMON);
  96             __bss_end__ = . ;
  97             ${RELOCATING+ end =  .};
  98             __data_end__ = . ;
  99         }
 100
 101   /* The exception handling table. A sequence of 5 word entries. Section
 102      address and extent are placed in the DataDirectory.
 103   */
 104   .pdata BLOCK(__section_alignment__) :
 105         {
 106             *(.pdata)
 107             ;
 108         }
 109
 110   /* The idata section is chock full of magic bits.
 111         1. Boundaries around various idata parts are used to initialize
 112            some of the fields of the DataDirectory. In particular, the
 113            magic for 2, 4 and 5 are known to be used. Some compilers
 114            appear to generate magic section symbols for this purpose.
 115            Where we can, we catch such symbols and use our own. This of
 116            course is something less than a perfect strategy.
 117         2. The table of contents is placed immediately after idata4.
 118            The ".private.toc" sections are generated by the ppc bfd. The
 119            .toc variable is generated by gas, and resolved here. It is
 120            used to initialized function descriptors (and anyone else who
 121            needs the address of the module's toc). The only thing
 122            interesting about it at all? Most ppc instructions using it
 123            have a 16bit displacement field. The convention for addressing
 124            is to initialize the .toc value to 32K past the start of the
 125            actual toc, and subtract 32K from all references, thus using
 126            the entire 64K range. Naturally, the reloc code must agree
 127            on this number or you get pretty stupid results.
 128   */
 129   .idata BLOCK(__section_alignment__) :
 130         {
 131             __idata2_magic__ = .;
 132             *(.idata\$2);
 133             __idata3_magic__ = .;
 134             *(.idata\$3);
 135             __idata4_magic__ = .;
 136             *(.idata\$4);
 137             . = ALIGN(4);
 138             .toc = . + 32768;
 139             *(.private.toc);
 140             __idata5_magic__ = .;
 141             *(.idata\$5);
 142             __idata6_magic__ = .;
 143             *(.idata\$6);
 144             __idata7_magic__ = .;
 145             *(.idata\$7);
 146             ;
 147         }
 148
 149   /* reldata -- data that requires relocation
 150   */
 151   .reldata BLOCK(__section_alignment__) :
 152         {
 153             *(.reldata)
 154             ;
 155         }
 156
 157
 158   /* Resources */
 159   .rsrc BLOCK(__section_alignment__) :
 160         {
 161             *(.rsrc\$01)
 162             *(.rsrc\$02)
 163             ;
 164         }
 165
 166   .stab BLOCK(__section_alignment__)  ${RELOCATING+(NOLOAD)} :
 167   {
 168     [ .stab ]
 169   }
 170
 171   .stabstr BLOCK(__section_alignment__) ${RELOCATING+(NOLOAD)} :
 172   {
 173     [ .stabstr ]
 174   }
 175
 176   /* The .reloc section is currently generated by the dlltool from Steve
 177      Chamberlain in a second pass of linking. Section address and extent
 178      are placed in the DataDirectory.
 179   */
 180   .reloc BLOCK(__section_alignment__) :
 181         {
 182             *(.reloc)
 183             ;
 184         }
 185
 186   /* We don't do anything useful with codeview debugger support or the
 187      directive section (yet). Hopefully, we junk them correctly.
 188   */
 189   /DISCARD/ BLOCK(__section_alignment__) :
 190         {
 191             *(.debug\$S)
 192             *(.debug\$T)
 193             *(.debug\$F)
 194             *(.drectve)
 195             ;
 196         }
 197 }
 198 EOF