#define HAVE_64BIT_OBJECTS (mips_abi == N64_ABI)
+/* True if relocations are stored in-place. */
+#define HAVE_IN_PLACE_ADDENDS (!HAVE_NEWABI)
+
/* We can only have 64bit addresses if the object file format supports it. */
#define HAVE_32BIT_ADDRESSES \
(HAVE_32BIT_GPRS \
static inline bfd_boolean
reloc_needs_lo_p (bfd_reloc_code_real_type reloc)
{
- return (reloc == BFD_RELOC_HI16_S
- || reloc == BFD_RELOC_MIPS_GOT16);
+ return (HAVE_IN_PLACE_ADDENDS
+ && (reloc == BFD_RELOC_HI16_S
+ || reloc == BFD_RELOC_MIPS_GOT16));
}
/* Return true if the given fixup is followed by a matching R_MIPS_LO16
int min_nops = 0;
const char *pn = prev_insn.insn_mo->name;
const char *tn = ip->insn_mo->name;
- if (strncmp(pn, "macc", 4) == 0
- || strncmp(pn, "dmacc", 5) == 0)
+ if (strncmp (pn, "macc", 4) == 0
+ || strncmp (pn, "dmacc", 5) == 0)
{
/* Errata 21 - [D]DIV[U] after [D]MACC */
if (strstr (tn, "div"))
- {
- min_nops = 1;
- }
+ min_nops = 1;
- /* Errata 23 - Continuous DMULT[U]/DMACC instructions */
- if (pn[0] == 'd' /* dmacc */
- && (strncmp(tn, "dmult", 5) == 0
- || strncmp(tn, "dmacc", 5) == 0))
- {
- min_nops = 1;
- }
+ /* VR4181A errata MD(1): "If a MULT, MULTU, DMULT or DMULTU
+ instruction is executed immediately after a MACC or
+ DMACC instruction, the result of [either instruction]
+ is incorrect." */
+ if (strncmp (tn, "mult", 4) == 0
+ || strncmp (tn, "dmult", 5) == 0)
+ min_nops = 1;
+
+ /* Errata 23 - Continuous DMULT[U]/DMACC instructions.
+ Applies on top of VR4181A MD(1) errata. */
+ if (pn[0] == 'd' && strncmp (tn, "dmacc", 5) == 0)
+ min_nops = 1;
/* Errata 24 - MT{LO,HI} after [D]MACC */
if (strcmp (tn, "mtlo") == 0
|| strcmp (tn, "mthi") == 0)
- {
- min_nops = 1;
- }
-
+ min_nops = 1;
}
- else if (strncmp(pn, "dmult", 5) == 0
- && (strncmp(tn, "dmult", 5) == 0
- || strncmp(tn, "dmacc", 5) == 0))
+ else if (strncmp (pn, "dmult", 5) == 0
+ && (strncmp (tn, "dmult", 5) == 0
+ || strncmp (tn, "dmacc", 5) == 0))
{
/* Here is the rest of errata 23. */
min_nops = 1;
}
+ else if ((strncmp (pn, "dmult", 5) == 0 || strstr (pn, "div"))
+ && (strncmp (tn, "macc", 4) == 0
+ || strncmp (tn, "dmacc", 5) == 0))
+ {
+ /* VR4181A errata MD(4): "If a MACC or DMACC instruction is
+ executed immediately after a DMULT, DMULTU, DIV, DIVU,
+ DDIV or DDIVU instruction, the result of the MACC or
+ DMACC instruction is incorrect.". This partly overlaps
+ the workaround for errata 23. */
+ min_nops = 1;
+ }
if (nops < min_nops)
nops = min_nops;
}
}
fixp[0] = fixp[1] = fixp[2] = NULL;
- if (address_expr != NULL && *reloc_type < BFD_RELOC_UNUSED)
+ if (address_expr != NULL && *reloc_type <= BFD_RELOC_UNUSED)
{
if (address_expr->X_op == O_constant)
{
ip->insn_opcode |= (address_expr->X_add_number >> 16) & 0xffff;
break;
+ case BFD_RELOC_UNUSED:
case BFD_RELOC_LO16:
case BFD_RELOC_MIPS_GOT_DISP:
ip->insn_opcode |= address_expr->X_add_number & 0xffff;
internalError ();
}
}
- else
+ else if (*reloc_type < BFD_RELOC_UNUSED)
need_reloc:
{
reloc_howto_type *howto;
md_number_to_chars (f, ip->insn_opcode >> 16, 2);
md_number_to_chars (f + 2, ip->insn_opcode & 0xffff, 2);
#ifdef OBJ_ELF
- dwarf2_emit_insn (4);
+ /* The value passed to dwarf2_emit_insn is the distance between
+ the end of the current instruction and the address that should
+ be recorded in the debug tables. Since we want to use ISA-encoded
+ addresses in MIPS16 debug info, the value is one byte less than
+ the real instruction length. */
+ dwarf2_emit_insn (3);
#endif
}
else
}
md_number_to_chars (f, ip->insn_opcode, 2);
#ifdef OBJ_ELF
- dwarf2_emit_insn (ip->use_extend ? 4 : 2);
+ dwarf2_emit_insn (ip->use_extend ? 3 : 1);
#endif
}
prev_insn_reloc_type[1] = BFD_RELOC_UNUSED;
prev_insn_reloc_type[2] = BFD_RELOC_UNUSED;
prev_insn_extended = 0;
+ prev_insn_is_delay_slot = 1;
}
else
{
{
int min_nops = 0;
const char *pn = prev_insn.insn_mo->name;
- if (strncmp(pn, "macc", 4) == 0
- || strncmp(pn, "dmacc", 5) == 0
- || strncmp(pn, "dmult", 5) == 0)
- {
- min_nops = 1;
- }
+ if (strncmp (pn, "macc", 4) == 0
+ || strncmp (pn, "dmacc", 5) == 0
+ || strncmp (pn, "dmult", 5) == 0
+ || strstr (pn, "div"))
+ min_nops = 1;
if (nops < min_nops)
nops = min_nops;
}
ip->insn_opcode |= (imm_expr.X_add_number
<< (OP_SH_VSEL +
(is_qh ? 2 : 1)));
+ imm_expr.X_op = O_absent;
if (*s != ']')
as_warn(_("Expecting ']' found '%s'"), s);
else
{
as_bad ("relocation %s isn't supported by the current ABI",
percent_op[i].str);
- *reloc = BFD_RELOC_LO16;
+ *reloc = BFD_RELOC_UNUSED;
}
return TRUE;
}
expression in *EP and the relocations in the array starting
at RELOC. Return the number of relocation operators used.
- On exit, EXPR_END points to the first character after the expression.
- If no relocation operators are used, RELOC[0] is set to BFD_RELOC_LO16. */
+ On exit, EXPR_END points to the first character after the expression. */
static size_t
my_getSmallExpression (expressionS *ep, bfd_reloc_code_real_type *reloc,
expr_end = str;
- if (reloc_index == 0)
- reloc[0] = BFD_RELOC_LO16;
- else
+ if (reloc_index != 0)
{
prev_reloc_op_frag = frag_now;
for (i = 0; i < reloc_index; i++)
#endif
}
-/* Sort any unmatched HI16_S relocs so that they immediately precede
- the corresponding LO reloc. This is called before md_apply_fix3 and
- tc_gen_reloc. Unmatched HI16_S relocs can only be generated by
- explicit use of the %hi modifier. */
+/* Sort any unmatched HI16 and GOT16 relocs so that they immediately precede
+ the corresponding LO16 reloc. This is called before md_apply_fix3 and
+ tc_gen_reloc. Unmatched relocs can only be generated by use of explicit
+ relocation operators.
+
+ For our purposes, a %lo() expression matches a %got() or %hi()
+ expression if:
+
+ (a) it refers to the same symbol; and
+ (b) the offset applied in the %lo() expression is no lower than
+ the offset applied in the %got() or %hi().
+
+ (b) allows us to cope with code like:
+
+ lui $4,%hi(foo)
+ lh $4,%lo(foo+2)($4)
+
+ ...which is legal on RELA targets, and has a well-defined behaviour
+ if the user knows that adding 2 to "foo" will not induce a carry to
+ the high 16 bits.
+
+ When several %lo()s match a particular %got() or %hi(), we use the
+ following rules to distinguish them:
+
+ (1) %lo()s with smaller offsets are a better match than %lo()s with
+ higher offsets.
+
+ (2) %lo()s with no matching %got() or %hi() are better than those
+ that already have a matching %got() or %hi().
+
+ (3) later %lo()s are better than earlier %lo()s.
+
+ These rules are applied in order.
+
+ (1) means, among other things, that %lo()s with identical offsets are
+ chosen if they exist.
+
+ (2) means that we won't associate several high-part relocations with
+ the same low-part relocation unless there's no alternative. Having
+ several high parts for the same low part is a GNU extension; this rule
+ allows careful users to avoid it.
+
+ (3) is purely cosmetic. mips_hi_fixup_list is is in reverse order,
+ with the last high-part relocation being at the front of the list.
+ It therefore makes sense to choose the last matching low-part
+ relocation, all other things being equal. It's also easier
+ to code that way. */
void
mips_frob_file (void)
for (l = mips_hi_fixup_list; l != NULL; l = l->next)
{
segment_info_type *seginfo;
- int pass;
+ bfd_boolean matched_lo_p;
+ fixS **hi_pos, **lo_pos, **pos;
assert (reloc_needs_lo_p (l->fixp->fx_r_type));
if (fixup_has_matching_lo_p (l->fixp))
continue;
- /* Look through the fixups for this segment for a matching %lo.
- When we find one, move the %hi just in front of it. We do
- this in two passes. In the first pass, we try to find a
- unique %lo. In the second pass, we permit multiple %hi
- relocs for a single %lo (this is a GNU extension). */
seginfo = seg_info (l->seg);
- for (pass = 0; pass < 2; pass++)
- {
- fixS *f, *prev;
- prev = NULL;
- for (f = seginfo->fix_root; f != NULL; f = f->fx_next)
+ /* Set HI_POS to the position of this relocation in the chain.
+ Set LO_POS to the position of the chosen low-part relocation.
+ MATCHED_LO_P is true on entry to the loop if *POS is a low-part
+ relocation that matches an immediately-preceding high-part
+ relocation. */
+ hi_pos = NULL;
+ lo_pos = NULL;
+ matched_lo_p = FALSE;
+ for (pos = &seginfo->fix_root; *pos != NULL; pos = &(*pos)->fx_next)
+ {
+ if (*pos == l->fixp)
+ hi_pos = pos;
+
+ if ((*pos)->fx_r_type == BFD_RELOC_LO16
+ && (*pos)->fx_addsy == l->fixp->fx_addsy
+ && (*pos)->fx_offset >= l->fixp->fx_offset
+ && (lo_pos == NULL
+ || (*pos)->fx_offset < (*lo_pos)->fx_offset
+ || (!matched_lo_p
+ && (*pos)->fx_offset == (*lo_pos)->fx_offset)))
+ lo_pos = pos;
+
+ matched_lo_p = (reloc_needs_lo_p ((*pos)->fx_r_type)
+ && fixup_has_matching_lo_p (*pos));
+ }
+
+ /* If we found a match, remove the high-part relocation from its
+ current position and insert it before the low-part relocation.
+ Make the offsets match so that fixup_has_matching_lo_p()
+ will return true.
+
+ We don't warn about unmatched high-part relocations since some
+ versions of gcc have been known to emit dead "lui ...%hi(...)"
+ instructions. */
+ if (lo_pos != NULL)
+ {
+ l->fixp->fx_offset = (*lo_pos)->fx_offset;
+ if (l->fixp->fx_next != *lo_pos)
{
- /* Check whether this is a %lo fixup which matches l->fixp. */
- if (f->fx_r_type == BFD_RELOC_LO16
- && f->fx_addsy == l->fixp->fx_addsy
- && f->fx_offset == l->fixp->fx_offset
- && (pass == 1
- || prev == NULL
- || !reloc_needs_lo_p (prev->fx_r_type)
- || !fixup_has_matching_lo_p (prev)))
- {
- fixS **pf;
-
- /* Move l->fixp before f. */
- for (pf = &seginfo->fix_root;
- *pf != l->fixp;
- pf = &(*pf)->fx_next)
- assert (*pf != NULL);
-
- *pf = l->fixp->fx_next;
-
- l->fixp->fx_next = f;
- if (prev == NULL)
- seginfo->fix_root = l->fixp;
- else
- prev->fx_next = l->fixp;
-
- break;
- }
-
- prev = f;
+ *hi_pos = l->fixp->fx_next;
+ l->fixp->fx_next = *lo_pos;
+ *lo_pos = l->fixp;
}
-
- if (f != NULL)
- break;
-
-#if 0 /* GCC code motion plus incomplete dead code elimination
- can leave a %hi without a %lo. */
- if (pass == 1)
- as_warn_where (l->fixp->fx_file, l->fixp->fx_line,
- _("Unmatched %%hi reloc"));
-#endif
}
}
}
&& fixP->fx_done
&& fixP->fx_frag->fr_address >= text_section->vma
&& (fixP->fx_frag->fr_address
- < text_section->vma + text_section->_raw_size)
+ < text_section->vma + bfd_get_section_size (text_section))
&& ((insn & 0xffff0000) == 0x10000000 /* beq $0,$0 */
|| (insn & 0xffff0000) == 0x04010000 /* bgez $0 */
|| (insn & 0xffff0000) == 0x04110000)) /* bgezal $0 */
}
/* This is called to see whether a reloc against a defined symbol
- should be converted into a reloc against a section. Don't adjust
- MIPS16 jump relocations, so we don't have to worry about the format
- of the offset in the .o file. Don't adjust relocations against
- mips16 symbols, so that the linker can find them if it needs to set
- up a stub. */
+ should be converted into a reloc against a section. */
int
mips_fix_adjustable (fixS *fixp)
{
+ /* Don't adjust MIPS16 jump relocations, so we don't have to worry
+ about the format of the offset in the .o file. */
if (fixp->fx_r_type == BFD_RELOC_MIPS16_JMP)
return 0;
if (fixp->fx_addsy == NULL)
return 1;
+ /* If symbol SYM is in a mergeable section, relocations of the form
+ SYM + 0 can usually be made section-relative. The mergeable data
+ is then identified by the section offset rather than by the symbol.
+
+ However, if we're generating REL LO16 relocations, the offset is split
+ between the LO16 and parterning high part relocation. The linker will
+ need to recalculate the complete offset in order to correctly identify
+ the merge data.
+
+ The linker has traditionally not looked for the parterning high part
+ relocation, and has thus allowed orphaned R_MIPS_LO16 relocations to be
+ placed anywhere. Rather than break backwards compatibility by changing
+ this, it seems better not to force the issue, and instead keep the
+ original symbol. This will work with either linker behavior. */
+ if ((fixp->fx_r_type == BFD_RELOC_LO16 || reloc_needs_lo_p (fixp->fx_r_type))
+ && HAVE_IN_PLACE_ADDENDS
+ && (S_GET_SEGMENT (fixp->fx_addsy)->flags & SEC_MERGE) != 0)
+ return 0;
+
#ifdef OBJ_ELF
+ /* Don't adjust relocations against mips16 symbols, so that the linker
+ can find them if it needs to set up a stub. */
if (OUTPUT_FLAVOR == bfd_target_elf_flavour
&& S_GET_OTHER (fixp->fx_addsy) == STO_MIPS16
&& fixp->fx_subsy == NULL)
projects / deliverable / binutils-gdb.git / blobdiff