diff options
Diffstat (limited to 'bfd/reloc.c')
| -rw-r--r-- | bfd/reloc.c | 427 |
1 files changed, 346 insertions, 81 deletions
diff --git a/bfd/reloc.c b/bfd/reloc.c index 0f05cbe..20dd050 100644 --- a/bfd/reloc.c +++ b/bfd/reloc.c @@ -43,8 +43,8 @@ SECTION */ #include "bfd.h" #include "sysdep.h" +#include "bfdlink.h" #include "libbfd.h" -#include "seclet.h" /* DOCDD INODE @@ -82,7 +82,8 @@ CODE_FRAGMENT . . {* The relocation was performed, but may not be ok - presently . generated only when linking i960 coff files with i960 b.out -. symbols. *} +. symbols. If this type is returned, the error_message argument +. to bfd_perform_relocation will be set. *} . bfd_reloc_dangerous . } . bfd_reloc_status_type; @@ -100,7 +101,7 @@ CODE_FRAGMENT . bfd_vma addend; . . {* Pointer to how to perform the required relocation *} -. CONST struct reloc_howto_struct *howto; +. const struct reloc_howto_struct *howto; . .} arelent; @@ -189,7 +190,7 @@ DESCRIPTION |offset type value |00000002 HVRT16 _foo+0x12340000 |00000006 LVRT16 _foo+0x12340000 - +| |00000000 5da05678 ; or.u r13,r0,0x5678 |00000004 1c4d5678 ; ld.b r2,r13,0x5678 |00000008 f400c001 ; jmp r1 @@ -214,7 +215,7 @@ DESCRIPTION | ret | restore - Both relocs contains a pointer to <<foo>>, and the offsets + Both relocs contain a pointer to <<foo>>, and the offsets contain junk. @@ -222,7 +223,7 @@ DESCRIPTION |offset type value |00000004 HI22 _foo+0x12345678 |00000008 LO10 _foo+0x12345678 - +| |00000000 9de3bf90 ; save %sp,-112,%sp |00000004 05000000 ; sethi %hi(_foo+0),%g2 |00000008 f048a000 ; ldsb [%g2+%lo(_foo+0)],%i0 @@ -296,16 +297,8 @@ CODE_FRAGMENT . unsigned int rightshift; . . {* The size of the item to be relocated. This is *not* a -. power-of-two measure. -. 0 : one byte -. 1 : two bytes -. 2 : four bytes -. 3 : nothing done (unless special_function is nonzero) -. 4 : eight bytes -. -2 : two bytes, result should be subtracted from the -. data instead of added -. There is currently no trivial way to extract a "number of -. bytes" from a howto pointer. *} +. power-of-two measure. To get the number of bytes operated +. on by a type of relocation, use bfd_get_reloc_size. *} . int size; . . {* The number of bits in the item to be relocated. This is used @@ -336,7 +329,8 @@ CODE_FRAGMENT . struct symbol_cache_entry *symbol, . PTR data, . asection *input_section, -. bfd *output_bfd)); +. bfd *output_bfd, +. char **error_message)); . . {* The textual name of the relocation type. *} . char *name; @@ -408,6 +402,33 @@ DESCRIPTION */ /* +FUNCTION + bfd_get_reloc_size + +SYNOPSIS + int bfd_get_reloc_size (const reloc_howto_type *); + +DESCRIPTION + For a reloc_howto_type that operates on a fixed number of bytes, + this returns the number of bytes operated on. + */ + +int +bfd_get_reloc_size (howto) + const reloc_howto_type *howto; +{ + switch (howto->size) { + case 0: return 1; + case 1: return 2; + case 2: return 4; + case 3: return 0; + case 4: return 8; + case -2: return 2; + default: abort (); + } +} + +/* TYPEDEF arelent_chain @@ -434,50 +455,50 @@ SYNOPSIS bfd_reloc_status_type bfd_perform_relocation (bfd *abfd, - arelent *reloc_entry, - PTR data, - asection *input_section, - bfd *output_bfd); + arelent *reloc_entry, + PTR data, + asection *input_section, + bfd *output_bfd, + char **error_message); DESCRIPTION - If @var{output_bfd} is supplied to this function, the generated - image will be relocatable; the relocations are copied to the - output file after they have been changed to reflect the new - state of the world. There are two ways of reflecting the - results of partial linkage in an output file: by modifying the - output data in place, and by modifying the relocation record. - Some native formats (e.g., basic a.out and basic coff) have no - way of specifying an addend in the relocation type, so the - addend has to go in the output data. This is no big deal - since in these formats the output data slot will always be big - enough for the addend. Complex reloc types with addends were - invented to solve just this problem. + If @var{output_bfd} is supplied to this function, the + generated image will be relocatable; the relocations are + copied to the output file after they have been changed to + reflect the new state of the world. There are two ways of + reflecting the results of partial linkage in an output file: + by modifying the output data in place, and by modifying the + relocation record. Some native formats (e.g., basic a.out and + basic coff) have no way of specifying an addend in the + relocation type, so the addend has to go in the output data. + This is no big deal since in these formats the output data + slot will always be big enough for the addend. Complex reloc + types with addends were invented to solve just this problem. + The @var{error_message} argument is set to an error message if + this return @code{bfd_reloc_dangerous}. */ bfd_reloc_status_type -DEFUN(bfd_perform_relocation,(abfd, - reloc_entry, - data, - input_section, - output_bfd), - bfd *abfd AND - arelent *reloc_entry AND - PTR data AND - asection *input_section AND - bfd *output_bfd) +bfd_perform_relocation (abfd, reloc_entry, data, input_section, output_bfd, + error_message) + bfd *abfd; + arelent *reloc_entry; + PTR data; + asection *input_section; + bfd *output_bfd; + char **error_message; { bfd_vma relocation; bfd_reloc_status_type flag = bfd_reloc_ok; bfd_size_type addr = reloc_entry->address ; bfd_vma output_base = 0; - reloc_howto_type *howto = reloc_entry->howto; - asection *reloc_target_output_section ; - + const reloc_howto_type *howto = reloc_entry->howto; + asection *reloc_target_output_section; asymbol *symbol; - symbol = *( reloc_entry->sym_ptr_ptr); + symbol = *(reloc_entry->sym_ptr_ptr); if ((symbol->section == &bfd_abs_section) && output_bfd != (bfd *)NULL) { @@ -500,7 +521,8 @@ DEFUN(bfd_perform_relocation,(abfd, { bfd_reloc_status_type cont; cont = howto->special_function (abfd, reloc_entry, symbol, data, - input_section, output_bfd); + input_section, output_bfd, + error_message); if (cont != bfd_reloc_continue) return cont; } @@ -891,7 +913,240 @@ space consuming. For each target: return flag; } +/* This relocation routine is used by some of the backend linkers. + They do not construct asymbol or arelent structures, so there is no + reason for them to use bfd_perform_relocation. Also, + bfd_perform_relocation is so hacked up it is easier to write a new + function than to try to deal with it. + + This routine does a final relocation. It should not be used when + generating relocateable output. + + FIXME: This routine ignores any special_function in the HOWTO, + since the existing special_function values have been written for + bfd_perform_relocation. + + HOWTO is the reloc howto information. + INPUT_BFD is the BFD which the reloc applies to. + INPUT_SECTION is the section which the reloc applies to. + CONTENTS is the contents of the section. + ADDRESS is the address of the reloc within INPUT_SECTION. + VALUE is the value of the symbol the reloc refers to. + ADDEND is the addend of the reloc. */ + +bfd_reloc_status_type +_bfd_final_link_relocate (howto, input_bfd, input_section, contents, address, + value, addend) + const reloc_howto_type *howto; + bfd *input_bfd; + asection *input_section; + bfd_byte *contents; + bfd_vma address; + bfd_vma value; + bfd_vma addend; +{ + bfd_vma relocation; + /* Sanity check the address. */ + if (address > input_section->_cooked_size) + return bfd_reloc_outofrange; + + /* This function assumes that we are dealing with a basic relocation + against a symbol. We want to compute the value of the symbol to + relocate to. This is just VALUE, the value of the symbol, plus + ADDEND, any addend associated with the reloc. */ + relocation = value + addend; + + /* If the relocation is PC relative, we want to set RELOCATION to + the distance between the symbol (currently in RELOCATION) and the + location we are relocating. Some targets (e.g., i386-aout) + arrange for the contents of the section to be the negative of the + offset of the location within the section; for such targets + pcrel_offset is false. Other targets (e.g., m88kbcs or ELF) + simply leave the contents of the section as zero; for such + targets pcrel_offset is true. If pcrel_offset is false we do not + need to subtract out the offset of the location within the + section (which is just ADDRESS). */ + if (howto->pc_relative) + { + relocation -= (input_section->output_section->vma + + input_section->output_offset); + if (howto->pcrel_offset) + relocation -= address; + } + + return _bfd_relocate_contents (howto, input_bfd, relocation, + contents + address); +} + +/* Relocate a given location using a given value and howto. */ + +bfd_reloc_status_type +_bfd_relocate_contents (howto, input_bfd, relocation, location) + const reloc_howto_type *howto; + bfd *input_bfd; + bfd_vma relocation; + bfd_byte *location; +{ + int size; + bfd_vma x; + boolean overflow; + + /* If the size is negative, negate RELOCATION. This isn't very + general. */ + if (howto->size < 0) + relocation = - relocation; + + /* Get the value we are going to relocate. */ + size = bfd_get_reloc_size (howto); + switch (size) + { + default: + case 0: + abort (); + case 1: + x = bfd_get_8 (input_bfd, location); + break; + case 2: + x = bfd_get_16 (input_bfd, location); + break; + case 4: + x = bfd_get_32 (input_bfd, location); + break; + case 8: +#ifdef BFD64 + x = bfd_get_64 (input_bfd, location); +#else + abort (); +#endif + break; + } + + /* Check for overflow. FIXME: We may drop bits during the addition + which we don't check for. We must either check at every single + operation, which would be tedious, or we must do the computations + in a type larger than bfd_vma, which would be inefficient. */ + overflow = false; + if (howto->complain_on_overflow != complain_overflow_dont) + { + bfd_vma check; + bfd_signed_vma signed_check; + bfd_vma add; + + if (howto->rightshift == 0) + { + check = relocation; + signed_check = (bfd_signed_vma) relocation; + } + else + { + /* Drop unwanted bits from the value we are relocating to. */ + check = relocation >> howto->rightshift; + + /* If this is a signed value, the rightshift just dropped + leading 1 bits (assuming twos complement). */ + if ((bfd_signed_vma) relocation >= 0) + signed_check = check; + else + signed_check = (check + | ((bfd_vma) -1 + &~ ((bfd_vma) -1 >> howto->rightshift))); + } + + /* Add in the value from the object file, shifted down so that + it is a straight number. */ + add = x & howto->src_mask; + if (howto->bitpos == 0) + { + check += add; + signed_check += add; + } + else + { + add >>= howto->bitpos; + check += add; + signed_check += (add + | ((bfd_vma) -1 + &~ ((bfd_vma) -1 >> howto->bitpos))); + } + + switch (howto->complain_on_overflow) + { + case complain_overflow_signed: + { + /* Assumes two's complement. */ + bfd_signed_vma reloc_signed_max = (1 << (howto->bitsize - 1)) - 1; + bfd_signed_vma reloc_signed_min = ~ reloc_signed_max; + + if (signed_check > reloc_signed_max + || signed_check < reloc_signed_min) + overflow = true; + } + break; + case complain_overflow_unsigned: + { + /* Assumes two's complement. This expression avoids + overflow if howto->bitsize is the number of bits in + bfd_vma. */ + bfd_vma reloc_unsigned_max = + (((1 << (howto->bitsize - 1)) - 1) << 1) | 1; + + if (check > reloc_unsigned_max) + overflow = true; + } + break; + case complain_overflow_bitfield: + { + /* Assumes two's complement. This expression avoids + overflow if howto->bitsize is the number of bits in + bfd_vma. */ + bfd_vma reloc_bits = (((1 << (howto->bitsize - 1)) - 1) << 1) | 1; + + if ((check &~ reloc_bits) != 0 + && (((bfd_vma) signed_check &~ reloc_bits) + != (-1 &~ reloc_bits))) + overflow = true; + } + break; + default: + abort (); + } + } + + /* Put RELOCATION in the right bits. */ + relocation >>= (bfd_vma) howto->rightshift; + relocation <<= (bfd_vma) howto->bitpos; + + /* Add RELOCATION to the right bits of X. */ + x = ((x &~ howto->dst_mask) + | (((x & howto->src_mask) + relocation) & howto->dst_mask)); + + /* Put the relocated value back in the object file. */ + switch (size) + { + default: + case 0: + abort (); + case 1: + bfd_put_8 (input_bfd, x, location); + break; + case 2: + bfd_put_16 (input_bfd, x, location); + break; + case 4: + bfd_put_32 (input_bfd, x, location); + break; + case 8: +#ifdef BFD64 + bfd_put_64 (input_bfd, x, location); +#else + abort (); +#endif + break; + } + + return overflow ? bfd_reloc_overflow : bfd_reloc_ok; +} /* DOCDD @@ -1147,18 +1402,18 @@ FUNCTION bfd_reloc_type_lookup SYNOPSIS - CONST struct reloc_howto_struct * + const struct reloc_howto_struct * bfd_reloc_type_lookup (bfd *abfd, bfd_reloc_code_real_type code); DESCRIPTION - Return a pointer to a howto struct which, when + Return a pointer to a howto structure which, when invoked, will perform the relocation @var{code} on data from the architecture noted. */ -CONST struct reloc_howto_struct * +const struct reloc_howto_struct * DEFUN(bfd_reloc_type_lookup,(abfd, code), bfd *abfd AND bfd_reloc_code_real_type code) @@ -1175,7 +1430,7 @@ INTERNAL_FUNCTION bfd_default_reloc_type_lookup SYNOPSIS - CONST struct reloc_howto_struct *bfd_default_reloc_type_lookup + const struct reloc_howto_struct *bfd_default_reloc_type_lookup (bfd *abfd AND bfd_reloc_code_real_type code); @@ -1185,7 +1440,7 @@ DESCRIPTION */ -CONST struct reloc_howto_struct * +const struct reloc_howto_struct * DEFUN(bfd_default_reloc_type_lookup, (abfd, code), bfd *abfd AND bfd_reloc_code_real_type code) @@ -1208,7 +1463,7 @@ DEFUN(bfd_default_reloc_type_lookup, (abfd, code), default: BFD_FAIL(); } - return (CONST struct reloc_howto_struct *)NULL; + return (const struct reloc_howto_struct *)NULL; } @@ -1220,6 +1475,7 @@ SYNOPSIS boolean bfd_generic_relax_section (bfd *abfd, asection *section, + struct bfd_link_info *, asymbol **symbols); DESCRIPTION @@ -1228,16 +1484,14 @@ DESCRIPTION */ boolean -DEFUN(bfd_generic_relax_section,(abfd, section, symbols), - bfd *abfd AND - asection *section AND - asymbol **symbols) +bfd_generic_relax_section (abfd, section, link_info, symbols) + bfd *abfd; + asection *section; + struct bfd_link_info *link_info; + asymbol **symbols; { - return false; - } - /* INTERNAL_FUNCTION @@ -1246,9 +1500,11 @@ INTERNAL_FUNCTION SYNOPSIS bfd_byte * bfd_generic_get_relocated_section_contents (bfd *abfd, - struct bfd_seclet *seclet, + struct bfd_link_info *link_info, + struct bfd_link_order *link_order, bfd_byte *data, - boolean relocateable); + boolean relocateable, + asymbol **symbols); DESCRIPTION Provides default handling of relocation effort for back ends @@ -1257,20 +1513,18 @@ DESCRIPTION */ bfd_byte * -DEFUN(bfd_generic_get_relocated_section_contents,(abfd, - seclet, - data, - relocateable), - bfd *abfd AND - struct bfd_seclet *seclet AND - bfd_byte *data AND - boolean relocateable) +bfd_generic_get_relocated_section_contents (abfd, link_info, link_order, data, + relocateable, symbols) + bfd *abfd; + struct bfd_link_info *link_info; + struct bfd_link_order *link_order; + bfd_byte *data; + boolean relocateable; + asymbol **symbols; { - extern bfd_error_vector_type bfd_error_vector; - /* Get enough memory to hold the stuff */ - bfd *input_bfd = seclet->u.indirect.section->owner; - asection *input_section = seclet->u.indirect.section; + bfd *input_bfd = link_order->u.indirect.section->owner; + asection *input_section = link_order->u.indirect.section; @@ -1292,18 +1546,20 @@ DEFUN(bfd_generic_get_relocated_section_contents,(abfd, if (bfd_canonicalize_reloc(input_bfd, input_section, reloc_vector, - seclet->u.indirect.symbols) ) + symbols) ) { arelent **parent; for (parent = reloc_vector; * parent != (arelent *)NULL; parent++) { + char *error_message = (char *) NULL; bfd_reloc_status_type r= bfd_perform_relocation(input_bfd, *parent, data, input_section, - relocateable ? abfd : (bfd *) NULL); + relocateable ? abfd : (bfd *) NULL, + &error_message); if (relocateable) { @@ -1319,15 +1575,24 @@ DEFUN(bfd_generic_get_relocated_section_contents,(abfd, switch (r) { case bfd_reloc_undefined: - bfd_error_vector.undefined_symbol(*parent, seclet); + if (! ((*link_info->callbacks->undefined_symbol) + (link_info, bfd_asymbol_name (*(*parent)->sym_ptr_ptr), + input_bfd, input_section, (*parent)->address))) + return NULL; break; case bfd_reloc_dangerous: - bfd_error_vector.reloc_dangerous(*parent, seclet); + BFD_ASSERT (error_message != (char *) NULL); + if (! ((*link_info->callbacks->reloc_dangerous) + (link_info, error_message, input_bfd, input_section, + (*parent)->address))) + return NULL; break; - case bfd_reloc_outofrange: case bfd_reloc_overflow: - bfd_error_vector.reloc_value_truncated(*parent, seclet); + if (! ((*link_info->callbacks->reloc_overflow) + (link_info, input_bfd, input_section, (*parent)->address))) + return NULL; break; + case bfd_reloc_outofrange: default: abort(); break; |