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authorIan Lance Taylor <ian@airs.com>1996-12-17 18:58:59 +0000
committerIan Lance Taylor <ian@airs.com>1996-12-17 18:58:59 +0000
commite4f4813f9c0d380a18baeb844481be9356b6baf8 (patch)
tree6a16a2392ca7485ef50e305abae5ac9e8d7d7d87
parent69e2ff181dffb4072f272bc33f7430fa82ed6e57 (diff)
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* elf32-mips.c (mips_elf_add_symbol_hook): Add 1 to the value of a
mips16 symbol during the link. (mips_elf_finish_dynamic_symbol): Subtract 1 from the value of a mips16 symbol. (mips_elf_link_output_symbol_hook): New static function. (elf_backend_link_output_symbol_hook): Define.
-rw-r--r--bfd/ChangeLog7
-rw-r--r--bfd/elf32-mips.c258
2 files changed, 257 insertions, 8 deletions
diff --git a/bfd/ChangeLog b/bfd/ChangeLog
index 17c196d..22d6dd0 100644
--- a/bfd/ChangeLog
+++ b/bfd/ChangeLog
@@ -1,5 +1,12 @@
Tue Dec 17 11:09:36 1996 Ian Lance Taylor <ian@cygnus.com>
+ * elf32-mips.c (mips_elf_add_symbol_hook): Add 1 to the value of a
+ mips16 symbol during the link.
+ (mips_elf_finish_dynamic_symbol): Subtract 1 from the value of a
+ mips16 symbol.
+ (mips_elf_link_output_symbol_hook): New static function.
+ (elf_backend_link_output_symbol_hook): Define.
+
* elf.c (bfd_elf_print_symbol): Print the st_other field if it is
not zero.
diff --git a/bfd/elf32-mips.c b/bfd/elf32-mips.c
index 1e13655..93631ac 100644
--- a/bfd/elf32-mips.c
+++ b/bfd/elf32-mips.c
@@ -41,6 +41,8 @@ Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
#define ECOFF_32
#include "ecoffswap.h"
+static bfd_reloc_status_type mips32_64bit_reloc
+ PARAMS ((bfd *, arelent *, asymbol *, PTR, asection *, bfd *, char **));
static reloc_howto_type *bfd_elf32_bfd_reloc_type_lookup
PARAMS ((bfd *, bfd_reloc_code_real_type));
static void mips_info_to_howto_rel
@@ -78,11 +80,16 @@ static void mips_elf_relocate_got_local
Elf_Internal_Rela *, bfd_byte *, bfd_vma));
static void mips_elf_relocate_global_got
PARAMS ((bfd *, Elf_Internal_Rela *, bfd_byte *, bfd_vma));
+static bfd_reloc_status_type mips16_jump_reloc
+ PARAMS ((bfd *, arelent *, asymbol *, PTR, asection *, bfd *, char **));
static boolean mips_elf_adjust_dynindx
PARAMS ((struct elf_link_hash_entry *, PTR));
static boolean mips_elf_relocate_section
PARAMS ((bfd *, struct bfd_link_info *, bfd *, asection *, bfd_byte *,
Elf_Internal_Rela *, Elf_Internal_Sym *, asection **));
+static boolean mips_elf_link_output_symbol_hook
+ PARAMS ((bfd *, struct bfd_link_info *, const char *, Elf_Internal_Sym *,
+ asection *));
static boolean mips_elf_create_dynamic_sections
PARAMS ((bfd *, struct bfd_link_info *));
static boolean mips_elf_create_compact_rel_section
@@ -296,7 +303,9 @@ enum reloc_type
R_MIPS_INSERT_B, R_MIPS_DELETE,
R_MIPS_HIGHER, R_MIPS_HIGHEST,
R_MIPS_CALL_HI16, R_MIPS_CALL_LO16,
- R_MIPS_max
+ R_MIPS_max,
+ /* This reloc is used for the mips16. */
+ R_MIPS16_26 = 100
};
static reloc_howto_type elf_mips_howto_table[] =
@@ -538,8 +547,23 @@ static reloc_howto_type elf_mips_howto_table[] =
0x000007c4, /* dst_mask */
false), /* pcrel_offset */
- /* A 64 bit relocation. Presumably not used in 32 bit ELF. */
- { R_MIPS_64 },
+ /* A 64 bit relocation. This is used in 32 bit ELF when addresses
+ are 64 bits long; the upper 32 bits are simply a sign extension.
+ The fields of the howto should be the same as for R_MIPS_32,
+ other than the type, name, and special_function. */
+ HOWTO (R_MIPS_64, /* type */
+ 0, /* rightshift */
+ 2, /* size (0 = byte, 1 = short, 2 = long) */
+ 32, /* bitsize */
+ false, /* pc_relative */
+ 0, /* bitpos */
+ complain_overflow_bitfield, /* complain_on_overflow */
+ mips32_64bit_reloc, /* special_function */
+ "R_MIPS_64", /* name */
+ true, /* partial_inplace */
+ 0xffffffff, /* src_mask */
+ 0xffffffff, /* dst_mask */
+ false), /* pcrel_offset */
/* Displacement in the global offset table. */
/* FIXME: Not handled correctly. */
@@ -667,6 +691,25 @@ static reloc_howto_type elf_mips_howto_table[] =
false) /* pcrel_offset */
};
+/* The reloc used for the mips16 jump instruction. */
+static reloc_howto_type elf_mips16_jump_howto =
+ HOWTO (R_MIPS16_26, /* type */
+ 2, /* rightshift */
+ 2, /* size (0 = byte, 1 = short, 2 = long) */
+ 26, /* bitsize */
+ false, /* pc_relative */
+ 0, /* bitpos */
+ complain_overflow_dont, /* complain_on_overflow */
+ /* This needs complex overflow
+ detection, because the upper four
+ bits must match the PC. */
+ mips16_jump_reloc, /* special_function */
+ "R_MIPS16_26", /* name */
+ true, /* partial_inplace */
+ 0x3ffffff, /* src_mask */
+ 0x3ffffff, /* dst_mask */
+ false); /* pcrel_offset */
+
/* Do a R_MIPS_HI16 relocation. This has to be done in combination
with a R_MIPS_LO16 reloc, because there is a carry from the LO16 to
the HI16. Here we just save the information we need; we do the
@@ -1226,6 +1269,78 @@ gprel32_with_gp (abfd, symbol, reloc_entry, input_section, relocateable, data,
return bfd_reloc_ok;
}
+/* Handle a 64 bit reloc in a 32 bit MIPS ELF file. These are
+ generated when addreses are 64 bits. The upper 32 bits are a simle
+ sign extension. */
+
+static bfd_reloc_status_type
+mips32_64bit_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;
+{
+ bfd_reloc_status_type r;
+ arelent reloc32;
+ unsigned long val;
+ bfd_size_type addr;
+
+ r = bfd_elf_generic_reloc (abfd, reloc_entry, symbol, data,
+ input_section, output_bfd, error_message);
+ if (r != bfd_reloc_continue)
+ return r;
+
+ /* Do a normal 32 bit relocation on the lower 32 bits. */
+ reloc32 = *reloc_entry;
+ if (bfd_big_endian (abfd))
+ reloc32.address += 4;
+ reloc32.howto = &elf_mips_howto_table[R_MIPS_32];
+ r = bfd_perform_relocation (abfd, &reloc32, data, input_section,
+ output_bfd, error_message);
+
+ /* Sign extend into the upper 32 bits. */
+ val = bfd_get_32 (abfd, (bfd_byte *) data + reloc32.address);
+ if ((val & 0x80000000) != 0)
+ val = 0xffffffff;
+ else
+ val = 0;
+ addr = reloc_entry->address;
+ if (bfd_little_endian (abfd))
+ addr += 4;
+ bfd_put_32 (abfd, val, (bfd_byte *) data + addr);
+
+ return r;
+}
+
+/* Handle a mips16 jump. */
+
+static bfd_reloc_status_type
+mips16_jump_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;
+{
+ if (output_bfd != (bfd *) NULL
+ && (symbol->flags & BSF_SECTION_SYM) == 0
+ && reloc_entry->addend == 0)
+ {
+ reloc_entry->address += input_section->output_offset;
+ return bfd_reloc_ok;
+ }
+
+ /* FIXME. */
+ abort ();
+}
+
/* A mapping from BFD reloc types to MIPS ELF reloc types. */
struct elf_reloc_map {
@@ -1239,6 +1354,7 @@ static CONST struct elf_reloc_map mips_reloc_map[] =
{ BFD_RELOC_16, R_MIPS_16 },
{ BFD_RELOC_32, R_MIPS_32 },
{ BFD_RELOC_CTOR, R_MIPS_32 },
+ { BFD_RELOC_64, R_MIPS_64 },
{ BFD_RELOC_MIPS_JMP, R_MIPS_26 },
{ BFD_RELOC_HI16_S, R_MIPS_HI16 },
{ BFD_RELOC_LO16, R_MIPS_LO16 },
@@ -1268,6 +1384,12 @@ bfd_elf32_bfd_reloc_type_lookup (abfd, code)
if (mips_reloc_map[i].bfd_reloc_val == code)
return &elf_mips_howto_table[(int) mips_reloc_map[i].elf_reloc_val];
}
+
+ /* Special handling for the MIPS16 jump, since it is a made up reloc
+ type with a large value. */
+ if (code == BFD_RELOC_MIPS16_JMP)
+ return &elf_mips16_jump_howto;
+
return NULL;
}
@@ -1282,8 +1404,13 @@ mips_info_to_howto_rel (abfd, cache_ptr, dst)
unsigned int r_type;
r_type = ELF32_R_TYPE (dst->r_info);
- BFD_ASSERT (r_type < (unsigned int) R_MIPS_max);
- cache_ptr->howto = &elf_mips_howto_table[r_type];
+ if (r_type == R_MIPS16_26)
+ cache_ptr->howto = &elf_mips16_jump_howto;
+ else
+ {
+ BFD_ASSERT (r_type < (unsigned int) R_MIPS_max);
+ cache_ptr->howto = &elf_mips_howto_table[r_type];
+ }
/* The addend for a GPREL16 or LITERAL relocation comes from the GP
value for the object file. We get the addend now, rather than
@@ -3036,6 +3163,12 @@ mips_elf_add_symbol_hook (abfd, info, sym, namep, flagsp, secp, valp)
mips_elf_hash_table (info)->use_rld_obj_head = true;
}
+ /* If this is a mips16 text symbol, add 1 to the value to make it
+ odd. This will cause something like .word SYM to come up with
+ the right value when it is loaded into the PC. */
+ if (sym->st_other == STO_MIPS16)
+ ++*valp;
+
return true;
}
@@ -4225,12 +4358,15 @@ mips_elf_relocate_section (output_bfd, info, input_bfd, input_section,
bfd_reloc_status_type r;
r_type = ELF32_R_TYPE (rel->r_info);
- if (r_type < 0 || r_type >= (int) R_MIPS_max)
+ if ((r_type < 0 || r_type >= (int) R_MIPS_max) && r_type != R_MIPS16_26)
{
bfd_set_error (bfd_error_bad_value);
return false;
}
- howto = elf_mips_howto_table + r_type;
+ if (r_type != R_MIPS16_26)
+ howto = elf_mips_howto_table + r_type;
+ else
+ howto = &elf_mips16_jump_howto;
if (dynobj != NULL
&& (r_type == R_MIPS_CALL16
@@ -4334,7 +4470,11 @@ mips_elf_relocate_section (output_bfd, info, input_bfd, input_section,
/* If this is HI16 or GOT16 with an associated LO16,
adjust the addend accordingly. Otherwise, just
relocate. */
- if (r_type != R_MIPS_HI16 && r_type != R_MIPS_GOT16)
+ if (r_type == R_MIPS_64 && bfd_big_endian (input_bfd))
+ r = _bfd_relocate_contents (howto, input_bfd,
+ addend,
+ contents + rel->r_offset + 4);
+ else if (r_type != R_MIPS_HI16 && r_type != R_MIPS_GOT16)
r = _bfd_relocate_contents (howto, input_bfd,
addend,
contents + rel->r_offset);
@@ -4394,6 +4534,10 @@ mips_elf_relocate_section (output_bfd, info, input_bfd, input_section,
value. */
if (ELF_ST_TYPE (sym->st_info) != STT_SECTION)
relocation += sym->st_value;
+
+ /* mips16 text labels should be treated as odd. */
+ if (sym->st_other == STO_MIPS16)
+ ++relocation;
}
else
{
@@ -4678,6 +4822,78 @@ mips_elf_relocate_section (output_bfd, info, input_bfd, input_section,
contents, rel->r_offset,
relocation, addend);
}
+ else if (r_type == R_MIPS_64)
+ {
+ bfd_size_type addr;
+ unsigned long val;
+
+ /* Do a 32 bit relocation, and sign extend to 64 bits. */
+ addr = rel->r_offset;
+ if (bfd_big_endian (input_bfd))
+ addr += 4;
+ r = _bfd_final_link_relocate (howto, input_bfd, input_section,
+ contents, addr, relocation,
+ addend);
+ val = bfd_get_32 (input_bfd, contents + addr);
+ if ((val & 0x80000000) != 0)
+ val = 0xffffffff;
+ else
+ val = 0;
+ addr = rel->r_offset;
+ if (bfd_little_endian (input_bfd))
+ addr += 4;
+ bfd_put_32 (input_bfd, val, contents + addr);
+ }
+ else if (r_type == R_MIPS_26
+ && ((h != NULL && h->other == STO_MIPS16)
+ || (sym != NULL && sym->st_other == STO_MIPS16)))
+ {
+ unsigned long insn;
+
+ /* This is a jump to a mips16 routine from a mips32
+ routine. We need to change jal into jalx. */
+ insn = bfd_get_32 (input_bfd, contents + rel->r_offset);
+ if (((insn >> 26) & 0x3f) != 0x3
+ && ((insn >> 26) & 0x3f) != 0x1d)
+ {
+ (*_bfd_error_handler)
+ ("%s: %s+0x%lx: jump to mips16 routine which is not jal",
+ bfd_get_filename (input_bfd),
+ input_section->name,
+ (unsigned long) rel->r_offset);
+ bfd_set_error (bfd_error_bad_value);
+ return false;
+ }
+ insn = (insn & 0x3ffffff) | (0x1d << 26);
+ bfd_put_32 (input_bfd, insn, contents + rel->r_offset);
+ r = _bfd_final_link_relocate (howto, input_bfd, input_section,
+ contents, rel->r_offset,
+ relocation, addend);
+ }
+ else if (r_type == R_MIPS16_26)
+ {
+ /* It's easiest to do the normal relocation, and then
+ dig out the instruction and swap the first word the
+ way the mips16 expects it. */
+ r = _bfd_final_link_relocate (howto, input_bfd, input_section,
+ contents, rel->r_offset,
+ relocation, addend);
+ if (r == bfd_reloc_ok)
+ {
+ unsigned long insn;
+
+ insn = bfd_get_16 (input_bfd, contents + rel->r_offset);
+ insn = ((insn & 0xfc00)
+ | ((insn & 0x1f) << 5)
+ | ((insn & 0x3e0) >> 5));
+ /* If this is a jump to a 32 bit routine, then make
+ it jalx. */
+ if ((h != NULL && h->other != STO_MIPS16)
+ || (sym != NULL && sym->st_other != STO_MIPS16))
+ insn |= 0x400;
+ bfd_put_16 (input_bfd, insn, contents + rel->r_offset);
+ }
+ }
else
r = _bfd_final_link_relocate (howto, input_bfd, input_section,
contents, rel->r_offset,
@@ -4764,6 +4980,25 @@ mips_elf_relocate_section (output_bfd, info, input_bfd, input_section,
return true;
}
+
+/* This hook function is called before the linker writes out a global
+ symbol. This is where we undo the increment of the value for a
+ mips16 symbol. */
+
+/*ARGSIGNORED*/
+static boolean
+mips_elf_link_output_symbol_hook (abfd, info, name, sym, input_sec)
+ bfd *abfd;
+ struct bfd_link_info *info;
+ const char *name;
+ Elf_Internal_Sym *sym;
+ asection *input_sec;
+{
+ if (sym->st_other == STO_MIPS16
+ && (sym->st_value & 1) != 0)
+ --sym->st_value;
+ return true;
+}
/* Functions for the dynamic linker. */
@@ -5845,6 +6080,11 @@ mips_elf_finish_dynamic_symbol (output_bfd, info, h, sym)
}
}
+ /* If this is a mips16 symbol, force the value to be even. */
+ if (sym->st_other == STO_MIPS16
+ && (sym->st_value & 1) != 0)
+ --sym->st_value;
+
return true;
}
@@ -6440,6 +6680,8 @@ static const struct ecoff_debug_swap mips_elf32_ecoff_debug_swap =
#define elf_backend_size_dynamic_sections \
mips_elf_size_dynamic_sections
#define elf_backend_relocate_section mips_elf_relocate_section
+#define elf_backend_link_output_symbol_hook \
+ mips_elf_link_output_symbol_hook
#define elf_backend_finish_dynamic_symbol \
mips_elf_finish_dynamic_symbol
#define elf_backend_finish_dynamic_sections \