Initial revision

1 files changed, 637 insertions, 0 deletions

diff --git a/bfd/coff-i386.c b/bfd/coff-i386.c
new file mode 100644
index 00000000000..7898cc159ca
--- /dev/null
+++ b/bfd/coff-i386.c
@@ -0,0 +1,637 @@
+/* BFD back-end for Intel 386 COFF files.
+   Copyright 1990, 91, 92, 93, 94, 95, 96, 97, 1998
+   Free Software Foundation, Inc.
+   Written by Cygnus Support.
+
+This file is part of BFD, the Binary File Descriptor library.
+
+This program is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program; if not, write to the Free Software
+Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
+
+#include "bfd.h"
+#include "sysdep.h"
+#include "libbfd.h"
+
+#include "coff/i386.h"
+
+#include "coff/internal.h"
+
+#ifdef COFF_WITH_PE
+#include "coff/pe.h"
+#endif
+
+#ifdef COFF_GO32_EXE
+#include "coff/go32exe.h"
+#endif
+
+#include "libcoff.h"
+
+static bfd_reloc_status_type coff_i386_reloc 
+  PARAMS ((bfd *, arelent *, asymbol *, PTR, asection *, bfd *, char **));
+static reloc_howto_type *coff_i386_rtype_to_howto
+  PARAMS ((bfd *, asection *, struct internal_reloc *,
+	   struct coff_link_hash_entry *, struct internal_syment *,
+
+	   bfd_vma *));
+
+#define COFF_DEFAULT_SECTION_ALIGNMENT_POWER (2)
+/* The page size is a guess based on ELF.  */
+
+#define COFF_PAGE_SIZE 0x1000
+
+/* For some reason when using i386 COFF the value stored in the .text
+   section for a reference to a common symbol is the value itself plus
+   any desired offset.  Ian Taylor, Cygnus Support.  */
+
+/* If we are producing relocateable output, we need to do some
+   adjustments to the object file that are not done by the
+   bfd_perform_relocation function.  This function is called by every
+   reloc type to make any required adjustments.  */
+
+static bfd_reloc_status_type
+coff_i386_reloc (abfd, reloc_entry, symbol, data, input_section, output_bfd,
+		 error_message)
+     bfd *abfd;
+     arelent *reloc_entry;
+     asymbol *symbol;
+     PTR data;
+     asection *input_section;
+     bfd *output_bfd;
+     char **error_message;
+{
+  symvalue diff;
+
+  if (output_bfd == (bfd *) NULL)
+    return bfd_reloc_continue;
+
+  if (bfd_is_com_section (symbol->section))
+    {
+#ifndef COFF_WITH_PE
+      /* We are relocating a common symbol.  The current value in the
+	 object file is ORIG + OFFSET, where ORIG is the value of the
+	 common symbol as seen by the object file when it was compiled
+	 (this may be zero if the symbol was undefined) and OFFSET is
+	 the offset into the common symbol (normally zero, but may be
+	 non-zero when referring to a field in a common structure).
+	 ORIG is the negative of reloc_entry->addend, which is set by
+	 the CALC_ADDEND macro below.  We want to replace the value in
+	 the object file with NEW + OFFSET, where NEW is the value of
+	 the common symbol which we are going to put in the final
+	 object file.  NEW is symbol->value.  */
+      diff = symbol->value + reloc_entry->addend;
+#else
+      /* In PE mode, we do not offset the common symbol.  */
+      diff = reloc_entry->addend;
+#endif
+    }
+  else
+    {
+      /* For some reason bfd_perform_relocation always effectively
+	 ignores the addend for a COFF target when producing
+	 relocateable output.  This seems to be always wrong for 386
+	 COFF, so we handle the addend here instead.  */
+      diff = reloc_entry->addend;
+    }
+
+#ifdef COFF_WITH_PE
+  /* FIXME: How should this case be handled?  */
+  if (reloc_entry->howto->type == R_IMAGEBASE && diff != 0)
+    abort ();
+#endif
+
+#define DOIT(x) \
+  x = ((x & ~howto->dst_mask) | (((x & howto->src_mask) + diff) & howto->dst_mask))
+
+    if (diff != 0)
+      {
+	reloc_howto_type *howto = reloc_entry->howto;
+	unsigned char *addr = (unsigned char *) data + reloc_entry->address;
+
+	switch (howto->size)
+	  {
+	  case 0:
+	    {
+	      char x = bfd_get_8 (abfd, addr);
+	      DOIT (x);
+	      bfd_put_8 (abfd, x, addr);
+	    }
+	    break;
+
+	  case 1:
+	    {
+	      short x = bfd_get_16 (abfd, addr);
+	      DOIT (x);
+	      bfd_put_16 (abfd, x, addr);
+	    }
+	    break;
+
+	  case 2:
+	    {
+	      long x = bfd_get_32 (abfd, addr);
+	      DOIT (x);
+	      bfd_put_32 (abfd, x, addr);
+	    }
+	    break;
+
+	  default:
+	    abort ();
+	  }
+      }
+
+  /* Now let bfd_perform_relocation finish everything up.  */
+  return bfd_reloc_continue;
+}
+
+#ifdef COFF_WITH_PE
+/* Return true if this relocation should
+   appear in the output .reloc section. */
+
+static boolean in_reloc_p(abfd, howto)
+     bfd * abfd;
+     reloc_howto_type *howto;
+{
+  return ! howto->pc_relative && howto->type != R_IMAGEBASE;
+}     
+#endif
+
+#ifndef PCRELOFFSET
+#define PCRELOFFSET false
+#endif
+
+static reloc_howto_type howto_table[] = 
+{
+  {0},
+  {1},
+  {2},
+  {3},
+  {4},
+  {5},
+  HOWTO (R_DIR32,               /* type */                                 
+	 0,	                /* rightshift */                           
+	 2,	                /* size (0 = byte, 1 = short, 2 = long) */ 
+	 32,	                /* bitsize */                   
+	 false,	                /* pc_relative */                          
+	 0,	                /* bitpos */                               
+	 complain_overflow_bitfield, /* complain_on_overflow */
+	 coff_i386_reloc,       /* special_function */                     
+	 "dir32",               /* name */                                 
+	 true,	                /* partial_inplace */                      
+	 0xffffffff,            /* src_mask */                             
+	 0xffffffff,            /* dst_mask */                             
+	 true),                /* pcrel_offset */
+  /* {7}, */
+  HOWTO (R_IMAGEBASE,            /* type */                                 
+	 0,	                /* rightshift */                           
+	 2,	                /* size (0 = byte, 1 = short, 2 = long) */ 
+	 32,	                /* bitsize */                   
+	 false,	                /* pc_relative */                          
+	 0,	                /* bitpos */                               
+	 complain_overflow_bitfield, /* complain_on_overflow */
+	 coff_i386_reloc,       /* special_function */                     
+	 "rva32",	           /* name */                                 
+	 true,	                /* partial_inplace */                      
+	 0xffffffff,            /* src_mask */                             
+	 0xffffffff,            /* dst_mask */                             
+	 false),                /* pcrel_offset */
+  {010},
+  {011},
+  {012},
+  {013},
+  {014},
+  {015},
+  {016},
+  HOWTO (R_RELBYTE,		/* type */                                 
+	 0,			/* rightshift */                           
+	 0,			/* size (0 = byte, 1 = short, 2 = long) */ 
+	 8,			/* bitsize */                   
+	 false,			/* pc_relative */                          
+	 0,			/* bitpos */                               
+	 complain_overflow_bitfield, /* complain_on_overflow */
+	 coff_i386_reloc,	/* special_function */                     
+	 "8",			/* name */                                 
+	 true,			/* partial_inplace */                      
+	 0x000000ff,		/* src_mask */                             
+	 0x000000ff,		/* dst_mask */                             
+	 PCRELOFFSET),		/* pcrel_offset */
+  HOWTO (R_RELWORD,		/* type */                                 
+	 0,			/* rightshift */                           
+	 1,			/* size (0 = byte, 1 = short, 2 = long) */ 
+	 16,			/* bitsize */                   
+	 false,			/* pc_relative */                          
+	 0,			/* bitpos */                               
+	 complain_overflow_bitfield, /* complain_on_overflow */
+	 coff_i386_reloc,	/* special_function */                     
+	 "16",			/* name */                                 
+	 true,			/* partial_inplace */                      
+	 0x0000ffff,		/* src_mask */                             
+	 0x0000ffff,		/* dst_mask */                             
+	 PCRELOFFSET),		/* pcrel_offset */
+  HOWTO (R_RELLONG,		/* type */                                 
+	 0,			/* rightshift */                           
+	 2,			/* size (0 = byte, 1 = short, 2 = long) */ 
+	 32,			/* bitsize */                   
+	 false,			/* pc_relative */                          
+	 0,			/* bitpos */                               
+	 complain_overflow_bitfield, /* complain_on_overflow */
+	 coff_i386_reloc,	/* special_function */                     
+	 "32",			/* name */                                 
+	 true,			/* partial_inplace */                      
+	 0xffffffff,		/* src_mask */                             
+	 0xffffffff,		/* dst_mask */                             
+	 PCRELOFFSET),		/* pcrel_offset */
+  HOWTO (R_PCRBYTE,		/* type */                                 
+	 0,			/* rightshift */                           
+	 0,			/* size (0 = byte, 1 = short, 2 = long) */ 
+	 8,			/* bitsize */                   
+	 true,			/* pc_relative */                          
+	 0,			/* bitpos */                               
+	 complain_overflow_signed, /* complain_on_overflow */
+	 coff_i386_reloc,	/* special_function */                     
+	 "DISP8",		/* name */                                 
+	 true,			/* partial_inplace */                      
+	 0x000000ff,		/* src_mask */                             
+	 0x000000ff,		/* dst_mask */                             
+	 PCRELOFFSET),		/* pcrel_offset */
+  HOWTO (R_PCRWORD,		/* type */                                 
+	 0,			/* rightshift */                           
+	 1,			/* size (0 = byte, 1 = short, 2 = long) */ 
+	 16,			/* bitsize */                   
+	 true,			/* pc_relative */                          
+	 0,			/* bitpos */                               
+	 complain_overflow_signed, /* complain_on_overflow */
+	 coff_i386_reloc,	/* special_function */                     
+	 "DISP16",		/* name */                                 
+	 true,			/* partial_inplace */                      
+	 0x0000ffff,		/* src_mask */                             
+	 0x0000ffff,		/* dst_mask */                             
+	 PCRELOFFSET),		/* pcrel_offset */
+  HOWTO (R_PCRLONG,		/* type */                                 
+	 0,			/* rightshift */                           
+	 2,			/* size (0 = byte, 1 = short, 2 = long) */ 
+	 32,			/* bitsize */                   
+	 true,			/* pc_relative */                          
+	 0,			/* bitpos */                               
+	 complain_overflow_signed, /* complain_on_overflow */
+	 coff_i386_reloc,	/* special_function */                     
+	 "DISP32",		/* name */                                 
+	 true,			/* partial_inplace */                      
+	 0xffffffff,		/* src_mask */                             
+	 0xffffffff,		/* dst_mask */                             
+	 PCRELOFFSET)		/* pcrel_offset */
+};
+
+/* Turn a howto into a reloc  nunmber */
+
+#define SELECT_RELOC(x,howto) { x.r_type = howto->type; }
+#define BADMAG(x) I386BADMAG(x)
+#define I386 1			/* Customize coffcode.h */
+
+#define RTYPE2HOWTO(cache_ptr, dst) \
+	    (cache_ptr)->howto = howto_table + (dst)->r_type;
+
+/* For 386 COFF a STYP_NOLOAD | STYP_BSS section is part of a shared
+   library.  On some other COFF targets STYP_BSS is normally
+   STYP_NOLOAD.  */
+#define BSS_NOLOAD_IS_SHARED_LIBRARY
+
+/* Compute the addend of a reloc.  If the reloc is to a common symbol,
+   the object file contains the value of the common symbol.  By the
+   time this is called, the linker may be using a different symbol
+   from a different object file with a different value.  Therefore, we
+   hack wildly to locate the original symbol from this file so that we
+   can make the correct adjustment.  This macro sets coffsym to the
+   symbol from the original file, and uses it to set the addend value
+   correctly.  If this is not a common symbol, the usual addend
+   calculation is done, except that an additional tweak is needed for
+   PC relative relocs.
+   FIXME: This macro refers to symbols and asect; these are from the
+   calling function, not the macro arguments.  */
+
+#define CALC_ADDEND(abfd, ptr, reloc, cache_ptr)		\
+  {								\
+    coff_symbol_type *coffsym = (coff_symbol_type *) NULL;	\
+    if (ptr && bfd_asymbol_bfd (ptr) != abfd)			\
+      coffsym = (obj_symbols (abfd)				\
+	         + (cache_ptr->sym_ptr_ptr - symbols));		\
+    else if (ptr)						\
+      coffsym = coff_symbol_from (abfd, ptr);			\
+    if (coffsym != (coff_symbol_type *) NULL			\
+	&& coffsym->native->u.syment.n_scnum == 0)		\
+      cache_ptr->addend = - coffsym->native->u.syment.n_value;	\
+    else if (ptr && bfd_asymbol_bfd (ptr) == abfd		\
+	     && ptr->section != (asection *) NULL)		\
+      cache_ptr->addend = - (ptr->section->vma + ptr->value);	\
+    else							\
+      cache_ptr->addend = 0;					\
+    if (ptr && howto_table[reloc.r_type].pc_relative)		\
+      cache_ptr->addend += asect->vma;				\
+  }
+
+/* We use the special COFF backend linker.  For normal i386 COFF, we
+   can use the generic relocate_section routine.  For PE, we need our
+   own routine.  */
+
+#ifndef COFF_WITH_PE
+
+#define coff_relocate_section _bfd_coff_generic_relocate_section
+
+#else /* COFF_WITH_PE */
+
+/* The PE relocate section routine.  The only difference between this
+   and the regular routine is that we don't want to do anything for a
+   relocateable link.  */
+
+static boolean coff_pe_i386_relocate_section
+  PARAMS ((bfd *, struct bfd_link_info *, bfd *, asection *, bfd_byte *,
+	   struct internal_reloc *, struct internal_syment *, asection **));
+
+static boolean
+coff_pe_i386_relocate_section (output_bfd, info, input_bfd,
+			       input_section, contents, relocs, syms,
+			       sections)
+     bfd *output_bfd;
+     struct bfd_link_info *info;
+     bfd *input_bfd;
+     asection *input_section;
+     bfd_byte *contents;
+     struct internal_reloc *relocs;
+     struct internal_syment *syms;
+     asection **sections;
+{
+  if (info->relocateable)
+    return true;
+
+  return _bfd_coff_generic_relocate_section (output_bfd, info, input_bfd,
+					     input_section, contents,
+					     relocs, syms, sections);
+}
+
+#define coff_relocate_section coff_pe_i386_relocate_section
+
+#endif /* COFF_WITH_PE */
+
+/* Convert an rtype to howto for the COFF backend linker.  */
+
+static reloc_howto_type *
+coff_i386_rtype_to_howto (abfd, sec, rel, h, sym, addendp)
+     bfd *abfd;
+     asection *sec;
+     struct internal_reloc *rel;
+     struct coff_link_hash_entry *h;
+     struct internal_syment *sym;
+     bfd_vma *addendp;
+{
+
+  reloc_howto_type *howto;
+
+  howto = howto_table + rel->r_type;
+
+#ifdef COFF_WITH_PE
+  *addendp = 0;
+#endif
+
+  if (howto->pc_relative)
+    *addendp += sec->vma;
+
+  if (sym != NULL && sym->n_scnum == 0 && sym->n_value != 0)
+    {
+      /* This is a common symbol.  The section contents include the
+	 size (sym->n_value) as an addend.  The relocate_section
+	 function will be adding in the final value of the symbol.  We
+	 need to subtract out the current size in order to get the
+	 correct result.  */
+ 
+      BFD_ASSERT (h != NULL);
+
+#ifndef COFF_WITH_PE
+      /* I think we *do* want to bypass this.  If we don't, I have
+	 seen some data parameters get the wrong relocation address.
+	 If I link two versions with and without this section bypassed
+	 and then do a binary comparison, the addresses which are
+	 different can be looked up in the map.  The case in which
+	 this section has been bypassed has addresses which correspond
+	 to values I can find in the map.  */
+      *addendp -= sym->n_value;
+#endif
+    }
+
+#ifndef COFF_WITH_PE
+  /* If the output symbol is common (in which case this must be a
+     relocateable link), we need to add in the final size of the
+     common symbol.  */
+  if (h != NULL && h->root.type == bfd_link_hash_common) 
+    *addendp += h->root.u.c.size;
+#endif
+
+#ifdef COFF_WITH_PE
+  if (howto->pc_relative)
+    {
+      *addendp -= 4;
+
+      /* If the symbol is defined, then the generic code is going to
+         add back the symbol value in order to cancel out an
+         adjustment it made to the addend.  However, we set the addend
+         to 0 at the start of this function.  We need to adjust here,
+         to avoid the adjustment the generic code will make.  FIXME:
+         This is getting a bit hackish.  */
+      if (sym != NULL && sym->n_scnum != 0)
+	*addendp -= sym->n_value;
+    }
+
+  if (rel->r_type == R_IMAGEBASE)
+    {
+      *addendp -= pe_data(sec->output_section->owner)->pe_opthdr.ImageBase;
+    }
+#endif
+
+  return howto;
+}
+
+
+#define coff_bfd_reloc_type_lookup coff_i386_reloc_type_lookup
+
+
+static reloc_howto_type *
+coff_i386_reloc_type_lookup (abfd, code)
+     bfd *abfd;
+     bfd_reloc_code_real_type code;
+{
+  switch (code)
+    {
+    case BFD_RELOC_RVA:
+      return howto_table +R_IMAGEBASE;
+    case BFD_RELOC_32:
+      return howto_table + R_DIR32;
+    case BFD_RELOC_32_PCREL:
+      return howto_table + R_PCRLONG;
+    default:
+      BFD_FAIL ();
+      return 0;
+    }
+}
+
+#define coff_rtype_to_howto coff_i386_rtype_to_howto
+
+#ifdef TARGET_UNDERSCORE
+
+/* If i386 gcc uses underscores for symbol names, then it does not use
+   a leading dot for local labels, so if TARGET_UNDERSCORE is defined
+   we treat all symbols starting with L as local.  */
+
+static boolean coff_i386_is_local_label_name PARAMS ((bfd *, const char *));
+
+static boolean
+coff_i386_is_local_label_name (abfd, name)
+     bfd *abfd;
+     const char *name;
+{
+  if (name[0] == 'L')
+    return true;
+
+  return _bfd_coff_is_local_label_name (abfd, name);
+}
+
+#define coff_bfd_is_local_label_name coff_i386_is_local_label_name
+
+#endif /* TARGET_UNDERSCORE */
+
+#include "coffcode.h"
+
+static const bfd_target *
+i3coff_object_p (abfd)
+     bfd *abfd;
+{
+#ifdef COFF_IMAGE_WITH_PE
+  /* We need to hack badly to handle a PE image correctly.  In PE
+     images created by the GNU linker, the offset to the COFF header
+     is always the size.  However, this is not the case in images
+     generated by other PE linkers.  The PE format stores a four byte
+     offset to the PE signature just before the COFF header at
+     location 0x3c of the file.  We pick up that offset, verify that
+     the PE signature is there, and then set ourselves up to read in
+     the COFF header.  */
+  {
+    bfd_byte ext_offset[4];
+    file_ptr offset;
+    bfd_byte ext_signature[4];
+    unsigned long signature;
+
+    if (bfd_seek (abfd, 0x3c, SEEK_SET) != 0
+	|| bfd_read (ext_offset, 1, 4, abfd) != 4)
+      {
+	if (bfd_get_error () != bfd_error_system_call)
+	  bfd_set_error (bfd_error_wrong_format);
+	return NULL;
+      }
+    offset = bfd_h_get_32 (abfd, ext_offset);
+    if (bfd_seek (abfd, offset, SEEK_SET) != 0
+	|| bfd_read (ext_signature, 1, 4, abfd) != 4)
+      {
+	if (bfd_get_error () != bfd_error_system_call)
+	  bfd_set_error (bfd_error_wrong_format);
+	return NULL;
+      }
+    signature = bfd_h_get_32 (abfd, ext_signature);
+
+    if (signature != 0x4550)
+      {
+	bfd_set_error (bfd_error_wrong_format);
+	return NULL;
+      }
+
+    /* Here is the hack.  coff_object_p wants to read filhsz bytes to
+       pick up the COFF header.  We adjust so that that will work.  20
+       is the size of the i386 COFF filehdr.  */
+
+    if (bfd_seek (abfd,
+		  (bfd_tell (abfd)
+		   - bfd_coff_filhsz (abfd)
+		   + 20),
+		  SEEK_SET)
+	!= 0)
+      {
+	if (bfd_get_error () != bfd_error_system_call)
+	  bfd_set_error (bfd_error_wrong_format);
+	return NULL;
+      }
+  }
+#endif
+
+  return coff_object_p (abfd);
+}
+
+const bfd_target
+#ifdef TARGET_SYM
+  TARGET_SYM =
+#else
+  i386coff_vec =
+#endif
+{
+#ifdef TARGET_NAME
+  TARGET_NAME,
+#else
+  "coff-i386",			/* name */
+#endif
+  bfd_target_coff_flavour,
+  BFD_ENDIAN_LITTLE,		/* data byte order is little */
+  BFD_ENDIAN_LITTLE,		/* header byte order is little */
+
+  (HAS_RELOC | EXEC_P |		/* object flags */
+   HAS_LINENO | HAS_DEBUG |
+   HAS_SYMS | HAS_LOCALS | WP_TEXT | D_PAGED),
+
+#ifndef COFF_WITH_PE
+  (SEC_HAS_CONTENTS | SEC_ALLOC | SEC_LOAD | SEC_RELOC /* section flags */
+   | SEC_CODE | SEC_DATA),
+#else
+  (SEC_HAS_CONTENTS | SEC_ALLOC | SEC_LOAD | SEC_RELOC /* section flags */
+   | SEC_CODE | SEC_DATA
+   | SEC_LINK_ONCE | SEC_LINK_DUPLICATES),
+#endif
+
+#ifdef TARGET_UNDERSCORE
+  TARGET_UNDERSCORE,		/* leading underscore */
+#else
+  0,				/* leading underscore */
+#endif
+  '/',				/* ar_pad_char */
+  15,				/* ar_max_namelen */
+
+  bfd_getl64, bfd_getl_signed_64, bfd_putl64,
+     bfd_getl32, bfd_getl_signed_32, bfd_putl32,
+     bfd_getl16, bfd_getl_signed_16, bfd_putl16, /* data */
+  bfd_getl64, bfd_getl_signed_64, bfd_putl64,
+     bfd_getl32, bfd_getl_signed_32, bfd_putl32,
+     bfd_getl16, bfd_getl_signed_16, bfd_putl16, /* hdrs */
+
+/* Note that we allow an object file to be treated as a core file as well. */
+    {_bfd_dummy_target, i3coff_object_p, /* bfd_check_format */
+       bfd_generic_archive_p, i3coff_object_p},
+    {bfd_false, coff_mkobject, _bfd_generic_mkarchive, /* bfd_set_format */
+       bfd_false},
+    {bfd_false, coff_write_object_contents, /* bfd_write_contents */
+       _bfd_write_archive_contents, bfd_false},
+
+     BFD_JUMP_TABLE_GENERIC (coff),
+     BFD_JUMP_TABLE_COPY (coff),
+     BFD_JUMP_TABLE_CORE (_bfd_nocore),
+     BFD_JUMP_TABLE_ARCHIVE (_bfd_archive_coff),
+     BFD_JUMP_TABLE_SYMBOLS (coff),
+     BFD_JUMP_TABLE_RELOCS (coff),
+     BFD_JUMP_TABLE_WRITE (coff),
+     BFD_JUMP_TABLE_LINK (coff),
+     BFD_JUMP_TABLE_DYNAMIC (_bfd_nodynamic),
+
+  COFF_SWAP_TABLE,
+};