aboutsummaryrefslogtreecommitdiff
path: root/gas/config/tc-mips.c
diff options
context:
space:
mode:
authorDaniel Jacobowitz <drow@false.org>2005-11-23 14:04:18 +0000
committerDaniel Jacobowitz <drow@false.org>2005-11-23 14:04:18 +0000
commitbad36eacdad37042c4efb1c5fbf48476b47de82b (patch)
tree09ba18d0af929dc68344a1788a63c3d48f0613e7 /gas/config/tc-mips.c
parenta14199dbd52888ecea9fc3d0e0f2c264c172f29c (diff)
downloadgdb-bad36eacdad37042c4efb1c5fbf48476b47de82b.zip
gdb-bad36eacdad37042c4efb1c5fbf48476b47de82b.tar.gz
gdb-bad36eacdad37042c4efb1c5fbf48476b47de82b.tar.bz2
bfd/
* elf32-mips.c (elf_mips_howto_table_rel): Use rightshift 2 for R_MIPS_PC16. (mips_reloc_map): Map BFD_RELOC_16_PCREL_S2 to R_MIPS_PC16. (bfd_elf32_bfd_reloc_type_lookup): Don't handle BFD_RELOC_16_PCREL_S2. * elf64-mips.c (mips_elf64_howto_table_rel): Use rightshift 2 for R_MIPS_PC16. (mips_elf64_howto_table_rela): Likewise. (mips_reloc_map): Map BFD_RELOC_16_PCREL_S2 to R_MIPS_PC16. (bfd_elf64_bfd_reloc_type_lookup): Don't handle BFD_RELOC_16_PCREL_S2. * elfn32-mips.c (elf_mips_howto_table_rel): Use rightshift 2 for R_MIPS_PC16. (elf_mips_howto_table_rela): Likewise. (mips_reloc_map): Map BFD_RELOC_16_PCREL_S2 to R_MIPS_PC16. (bfd_elf32_bfd_reloc_type_lookup): Don't handle BFD_RELOC_16_PCREL_S2. * elfxx-mips.c: Formatting fixes. (mips_elf_calculate_relocation): Handle R_MIPS_GNU_REL16_S2 and R_MIPS_PC16 identically. gas/ * config/tc-mips.c (append_insn): Handle BFD_RELOC_16_PCREL_S2. (macro_build): Complain for invalid branch displacements. (mips_validate_fix): Delete. (md_apply_fix): Re-add pcrel support for branches. Use consistent text for misaligned branch targets. (tc_gen_reloc: Re-add pcrel support for branches. Handle strange BFD pcrel processing. Remove error for unresolved branches. * config/tc-mips.h (TC_VALIDATE_FIX, mips_validate_fix): Delete. gas/testsuite/ * gas/mips/bge.d, gas/mips/bge.s, gas/mips/bgeu.d, gas/mips/bgeu.s, gas/mips/blt.d, gas/mips/blt.s, gas/mips/bltu.d, gas/mips/bltu.s: Reactivate external branch tests. * gas/mips/branch-misc-2.d, gas/mips/branch-misc-2pic.d, gas/mips/branch-misc-2-64.d, gas/mips/branch-misc-2pic-64.d: New tests. * gas/mips/branch-misc-2.l, gas/mips/branch-misc-2pic.l, gas/testsuite/gas/mips/branch-misc-2pic.s: Remove. * gas/mips/mips.exp: Adjust branch-misc-2 tests. Add 64-bit variants.
Diffstat (limited to 'gas/config/tc-mips.c')
-rw-r--r--gas/config/tc-mips.c144
1 files changed, 43 insertions, 101 deletions
diff --git a/gas/config/tc-mips.c b/gas/config/tc-mips.c
index 4f1afea..557fb40 100644
--- a/gas/config/tc-mips.c
+++ b/gas/config/tc-mips.c
@@ -2410,7 +2410,16 @@ append_insn (struct mips_cl_insn *ip, expressionS *address_expr,
break;
case BFD_RELOC_16_PCREL_S2:
- goto need_reloc;
+ if ((address_expr->X_add_number & 3) != 0)
+ as_bad (_("branch to misaligned address (0x%lx)"),
+ (unsigned long) address_expr->X_add_number);
+ if (mips_relax_branch)
+ goto need_reloc;
+ if ((address_expr->X_add_number + 0x20000) & ~0x3ffff)
+ as_bad (_("branch address range overflow (0x%lx)"),
+ (unsigned long) address_expr->X_add_number);
+ ip->insn_opcode |= (address_expr->X_add_number >> 2) & 0xffff;
+ break;
default:
internalError ();
@@ -3139,15 +3148,22 @@ macro_build (expressionS *ep, const char *name, const char *fmt, ...)
case 'p':
assert (ep != NULL);
+
/*
* This allows macro() to pass an immediate expression for
* creating short branches without creating a symbol.
- * Note that the expression still might come from the assembly
- * input, in which case the value is not checked for range nor
- * is a relocation entry generated (yuck).
+ *
+ * We don't allow branch relaxation for these branches, as
+ * they should only appear in ".set nomacro" anyway.
*/
if (ep->X_op == O_constant)
{
+ if ((ep->X_add_number & 3) != 0)
+ as_bad (_("branch to misaligned address (0x%lx)"),
+ (unsigned long) ep->X_add_number);
+ if ((ep->X_add_number + 0x20000) & ~0x3ffff)
+ as_bad (_("branch address range overflow (0x%lx)"),
+ (unsigned long) ep->X_add_number);
insn.insn_opcode |= (ep->X_add_number >> 2) & 0xffff;
ep = NULL;
}
@@ -11361,83 +11377,6 @@ mips_force_relocation (fixS *fixp)
return 0;
}
-/* This hook is called before a fix is simplified. We don't really
- decide whether to skip a fix here. Rather, we turn global symbols
- used as branch targets into local symbols, such that they undergo
- simplification. We can only do this if the symbol is defined and
- it is in the same section as the branch. If this doesn't hold, we
- emit a better error message than just saying the relocation is not
- valid for the selected object format.
-
- FIXP is the fix-up we're going to try to simplify, SEG is the
- segment in which the fix up occurs. The return value should be
- non-zero to indicate the fix-up is valid for further
- simplifications. */
-
-int
-mips_validate_fix (struct fix *fixP, asection *seg)
-{
- /* There's a lot of discussion on whether it should be possible to
- use R_MIPS_PC16 to represent branch relocations. The outcome
- seems to be that it can, but gas/bfd are very broken in creating
- RELA relocations for this, so for now we only accept branches to
- symbols in the same section. Anything else is of dubious value,
- since there's no guarantee that at link time the symbol would be
- in range. Even for branches to local symbols this is arguably
- wrong, since it we assume the symbol is not going to be
- overridden, which should be possible per ELF library semantics,
- but then, there isn't a dynamic relocation that could be used to
- this effect, and the target would likely be out of range as well.
-
- Unfortunately, it seems that there is too much code out there
- that relies on branches to symbols that are global to be resolved
- as if they were local, like the IRIX tools do, so we do it as
- well, but with a warning so that people are reminded to fix their
- code. If we ever get back to using R_MIPS_PC16 for branch
- targets, this entire block should go away (and probably the
- whole function). */
-
- if (fixP->fx_r_type == BFD_RELOC_16_PCREL_S2
- && ((OUTPUT_FLAVOR == bfd_target_ecoff_flavour
- || OUTPUT_FLAVOR == bfd_target_elf_flavour)
- || bfd_reloc_type_lookup (stdoutput, BFD_RELOC_16_PCREL_S2) == NULL)
- && fixP->fx_addsy)
- {
- if (! S_IS_DEFINED (fixP->fx_addsy))
- {
- as_bad_where (fixP->fx_file, fixP->fx_line,
- _("Cannot branch to undefined symbol."));
- /* Avoid any further errors about this fixup. */
- fixP->fx_done = 1;
- }
- else if (S_GET_SEGMENT (fixP->fx_addsy) != seg)
- {
- as_bad_where (fixP->fx_file, fixP->fx_line,
- _("Cannot branch to symbol in another section."));
- fixP->fx_done = 1;
- }
- else if (S_IS_EXTERNAL (fixP->fx_addsy))
- {
- symbolS *sym = fixP->fx_addsy;
-
- if (mips_pic == SVR4_PIC)
- as_warn_where (fixP->fx_file, fixP->fx_line,
- _("Pretending global symbol used as branch target is local."));
-
- fixP->fx_addsy = symbol_create (S_GET_NAME (sym),
- S_GET_SEGMENT (sym),
- S_GET_VALUE (sym),
- symbol_get_frag (sym));
- copy_symbol_attributes (fixP->fx_addsy, sym);
- S_CLEAR_EXTERNAL (fixP->fx_addsy);
- assert (symbol_resolved_p (sym));
- symbol_mark_resolved (fixP->fx_addsy);
- }
- }
-
- return 1;
-}
-
/* Apply a fixup to the object file. */
void
@@ -11462,7 +11401,7 @@ md_apply_fix (fixS *fixP, valueT *valP, segT seg ATTRIBUTE_UNUSED)
buf = (bfd_byte *) (fixP->fx_frag->fr_literal + fixP->fx_where);
- assert (! fixP->fx_pcrel);
+ assert (! fixP->fx_pcrel || fixP->fx_r_type == BFD_RELOC_16_PCREL_S2);
/* Don't treat parts of a composite relocation as done. There are two
reasons for this:
@@ -11474,7 +11413,7 @@ md_apply_fix (fixS *fixP, valueT *valP, segT seg ATTRIBUTE_UNUSED)
constants. The easiest way of dealing with the pathological
exceptions is to generate a relocation against STN_UNDEF and
leave everything up to the linker. */
- if (fixP->fx_addsy == NULL && fixP->fx_tcbit == 0)
+ if (fixP->fx_addsy == NULL && ! fixP->fx_pcrel && fixP->fx_tcbit == 0)
fixP->fx_done = 1;
switch (fixP->fx_r_type)
@@ -11519,7 +11458,6 @@ md_apply_fix (fixS *fixP, valueT *valP, segT seg ATTRIBUTE_UNUSED)
case BFD_RELOC_MIPS16_GPREL:
case BFD_RELOC_MIPS16_HI16:
case BFD_RELOC_MIPS16_HI16_S:
- assert (! fixP->fx_pcrel);
/* Nothing needed to do. The value comes from the reloc entry */
break;
@@ -11589,7 +11527,7 @@ md_apply_fix (fixS *fixP, valueT *valP, segT seg ATTRIBUTE_UNUSED)
case BFD_RELOC_16_PCREL_S2:
if ((*valP & 0x3) != 0)
as_bad_where (fixP->fx_file, fixP->fx_line,
- _("Branch to odd address (%lx)"), (long) *valP);
+ _("Branch to misaligned address (%lx)"), (long) *valP);
/*
* We need to save the bits in the instruction since fixup_segment()
@@ -13307,8 +13245,24 @@ tc_gen_reloc (asection *section ATTRIBUTE_UNUSED, fixS *fixp)
*reloc->sym_ptr_ptr = symbol_get_bfdsym (fixp->fx_addsy);
reloc->address = fixp->fx_frag->fr_address + fixp->fx_where;
- assert (! fixp->fx_pcrel);
- reloc->addend = fixp->fx_addnumber;
+ if (fixp->fx_pcrel)
+ {
+ assert (fixp->fx_r_type == BFD_RELOC_16_PCREL_S2);
+
+ /* At this point, fx_addnumber is "symbol offset - pcrel address".
+ Relocations want only the symbol offset. */
+ reloc->addend = fixp->fx_addnumber + reloc->address;
+ if (OUTPUT_FLAVOR != bfd_target_elf_flavour)
+ {
+ /* A gruesome hack which is a result of the gruesome gas
+ reloc handling. What's worse, for COFF (as opposed to
+ ECOFF), we might need yet another copy of reloc->address.
+ See bfd_install_relocation. */
+ reloc->addend += reloc->address;
+ }
+ }
+ else
+ reloc->addend = fixp->fx_addnumber;
/* Since the old MIPS ELF ABI uses Rel instead of Rela, encode the vtable
entry to be used in the relocation's section offset. */
@@ -13320,18 +13274,7 @@ tc_gen_reloc (asection *section ATTRIBUTE_UNUSED, fixS *fixp)
code = fixp->fx_r_type;
- /* To support a PC relative reloc, we used a Cygnus extension.
- We check for that here to make sure that we don't let such a
- reloc escape normally. (FIXME: This was formerly used by
- embedded-PIC support, but is now used by branch handling in
- general. That probably should be fixed.) */
- if ((OUTPUT_FLAVOR == bfd_target_ecoff_flavour
- || OUTPUT_FLAVOR == bfd_target_elf_flavour)
- && code == BFD_RELOC_16_PCREL_S2)
- reloc->howto = NULL;
- else
- reloc->howto = bfd_reloc_type_lookup (stdoutput, code);
-
+ reloc->howto = bfd_reloc_type_lookup (stdoutput, code);
if (reloc->howto == NULL)
{
as_bad_where (fixp->fx_file, fixp->fx_line,
@@ -13408,8 +13351,7 @@ md_convert_frag (bfd *abfd ATTRIBUTE_UNUSED, segT asec, fragS *fragp)
exp.X_add_number = fragp->fr_offset;
fixp = fix_new_exp (fragp, buf - (bfd_byte *)fragp->fr_literal,
- 4, &exp, 1,
- BFD_RELOC_16_PCREL_S2);
+ 4, &exp, 1, BFD_RELOC_16_PCREL_S2);
fixp->fx_file = fragp->fr_file;
fixp->fx_line = fragp->fr_line;