aboutsummaryrefslogtreecommitdiff
path: root/bfd/elf64-alpha.c
diff options
context:
space:
mode:
authorRichard Henderson <rth@redhat.com>2005-05-22 22:13:21 +0000
committerRichard Henderson <rth@redhat.com>2005-05-22 22:13:21 +0000
commitd6ad34f6c2faf777ea2c4e17fb492583cd6b55d4 (patch)
treea2a975aaa0e765fb87da650c86664e6390dd0d79 /bfd/elf64-alpha.c
parent487c435301ca74f6ef5dced9e1a0e60815ecddb7 (diff)
downloadgdb-d6ad34f6c2faf777ea2c4e17fb492583cd6b55d4.zip
gdb-d6ad34f6c2faf777ea2c4e17fb492583cd6b55d4.tar.gz
gdb-d6ad34f6c2faf777ea2c4e17fb492583cd6b55d4.tar.bz2
* elf64-alpha.c (elf64_alpha_relax_with_lituse): Relax jsr to
undefweak to use zero register. Call elf64_alpha_relax_got_load if not all uses removed. (elf64_alpha_relax_got_load): Relax undefweak to lda zero. (elf64_alpha_relax_section): Handle undefweak symbols. (elf64_alpha_calc_dynrel_sizes): Don't add relocs for undefweak. (elf64_alpha_size_rela_got_1): Likewise. (elf64_alpha_relocate_section): Likewise.
Diffstat (limited to 'bfd/elf64-alpha.c')
-rw-r--r--bfd/elf64-alpha.c121
1 files changed, 84 insertions, 37 deletions
diff --git a/bfd/elf64-alpha.c b/bfd/elf64-alpha.c
index 1778b92..8662129 100644
--- a/bfd/elf64-alpha.c
+++ b/bfd/elf64-alpha.c
@@ -1300,9 +1300,7 @@ elf64_alpha_relax_with_lituse (info, symval, irel)
/* Extract the displacement from the instruction, sign-extending
it if necessary, then test whether it is within 16 or 32 bits
displacement from GP. */
- insn_disp = insn & 0x0000ffff;
- if (insn_disp & 0x8000)
- insn_disp |= ~0xffff; /* Negative: sign-extend. */
+ insn_disp = ((insn & 0xffff) ^ 0x8000) - 0x8000;
xdisp = disp + insn_disp;
fits16 = (xdisp >= - (bfd_signed_vma) 0x8000 && xdisp < 0x8000);
@@ -1371,6 +1369,19 @@ elf64_alpha_relax_with_lituse (info, symval, irel)
bfd_vma optdest, org;
bfd_signed_vma odisp;
+ /* For undefined weak symbols, we're mostly interested in getting
+ rid of the got entry whenever possible, so optimize this to a
+ use of the zero register. */
+ if (info->h && info->h->root.root.type == bfd_link_hash_undefweak)
+ {
+ insn |= 31 << 16;
+ bfd_put_32 (info->abfd, (bfd_vma) insn,
+ info->contents + urel->r_offset);
+
+ info->changed_contents = TRUE;
+ break;
+ }
+
/* If not zero, place to jump without needing pv. */
optdest = elf64_alpha_relax_opt_call (info, symval);
org = (info->sec->output_section->vma
@@ -1474,9 +1485,11 @@ elf64_alpha_relax_with_lituse (info, symval, irel)
info->contents + irel->r_offset);
info->changed_contents = TRUE;
}
- }
- return TRUE;
+ return TRUE;
+ }
+ else
+ return elf64_alpha_relax_got_load (info, symval, irel, R_ALPHA_LITERAL);
}
static bfd_vma
@@ -1583,7 +1596,25 @@ elf64_alpha_relax_got_load (info, symval, irel, r_type)
return TRUE;
if (r_type == R_ALPHA_LITERAL)
- disp = symval - info->gp;
+ {
+ /* Look for nice constant addresses. This includes the not-uncommon
+ special case of 0 for undefweak symbols. */
+ if ((info->h && info->h->root.root.type == bfd_link_hash_undefweak)
+ || (!info->link_info->shared
+ && (symval >= (bfd_vma)-0x8000 || symval < 0x8000)))
+ {
+ disp = 0;
+ insn = (OP_LDA << 26) | (insn & (31 << 21)) | (31 << 16);
+ insn |= (symval & 0xffff);
+ r_type = R_ALPHA_NONE;
+ }
+ else
+ {
+ disp = symval - info->gp;
+ insn = (OP_LDA << 26) | (insn & 0x03ff0000);
+ r_type = R_ALPHA_GPREL16;
+ }
+ }
else
{
bfd_vma dtp_base, tp_base;
@@ -1592,17 +1623,26 @@ elf64_alpha_relax_got_load (info, symval, irel, r_type)
dtp_base = alpha_get_dtprel_base (info->link_info);
tp_base = alpha_get_tprel_base (info->link_info);
disp = symval - (r_type == R_ALPHA_GOTDTPREL ? dtp_base : tp_base);
+
+ insn = (OP_LDA << 26) | (insn & (31 << 21)) | (31 << 16);
+
+ switch (r_type)
+ {
+ case R_ALPHA_GOTDTPREL:
+ r_type = R_ALPHA_DTPREL16;
+ break;
+ case R_ALPHA_GOTTPREL:
+ r_type = R_ALPHA_TPREL16;
+ break;
+ default:
+ BFD_ASSERT (0);
+ return FALSE;
+ }
}
if (disp < -0x8000 || disp >= 0x8000)
return TRUE;
- /* Exchange LDQ for LDA. In the case of the TLS relocs, we're loading
- a constant, so force the base register to be $31. */
- if (r_type == R_ALPHA_LITERAL)
- insn = (OP_LDA << 26) | (insn & 0x03ff0000);
- else
- insn = (OP_LDA << 26) | (insn & (31 << 21)) | (31 << 16);
bfd_put_32 (info->abfd, (bfd_vma) insn, info->contents + irel->r_offset);
info->changed_contents = TRUE;
@@ -1617,22 +1657,6 @@ elf64_alpha_relax_got_load (info, symval, irel, r_type)
}
/* Smash the existing GOT relocation for its 16-bit immediate pair. */
- switch (r_type)
- {
- case R_ALPHA_LITERAL:
- r_type = R_ALPHA_GPREL16;
- break;
- case R_ALPHA_GOTDTPREL:
- r_type = R_ALPHA_DTPREL16;
- break;
- case R_ALPHA_GOTTPREL:
- r_type = R_ALPHA_TPREL16;
- break;
- default:
- BFD_ASSERT (0);
- return FALSE;
- }
-
irel->r_info = ELF64_R_INFO (ELF64_R_SYM (irel->r_info), r_type);
info->changed_relocs = TRUE;
@@ -2103,13 +2127,17 @@ elf64_alpha_relax_section (abfd, sec, link_info, again)
h = (struct alpha_elf_link_hash_entry *)h->root.root.u.i.link;
/* If the symbol is undefined, we can't do anything with it. */
- if (h->root.root.type == bfd_link_hash_undefweak
- || h->root.root.type == bfd_link_hash_undefined)
+ if (h->root.root.type == bfd_link_hash_undefined)
continue;
- /* If the symbol isn't defined in the current module, again
- we can't do anything. */
- if (!h->root.def_regular)
+ /* If the symbol isn't defined in the current module,
+ again we can't do anything. */
+ if (h->root.root.type == bfd_link_hash_undefweak)
+ {
+ info.tsec = bfd_abs_section_ptr;
+ symval = 0;
+ }
+ else if (!h->root.def_regular)
{
/* Except for TLSGD relocs, which can sometimes be
relaxed to GOTTPREL relocs. */
@@ -3860,9 +3888,14 @@ elf64_alpha_calc_dynrel_sizes (h, info)
/* If the symbol is dynamic, we'll need all the relocations in their
natural form. If this is a shared object, and it has been forced
local, we'll need the same number of RELATIVE relocations. */
-
dynamic = alpha_elf_dynamic_symbol_p (&h->root, info);
+ /* If the symbol is a hidden undefined weak, then we never have any
+ relocations. Avoid the loop which may want to add RELATIVE relocs
+ based on info->shared. */
+ if (h->root.root.type == bfd_link_hash_undefweak && !dynamic)
+ return TRUE;
+
for (relent = h->reloc_entries; relent; relent = relent->next)
{
entries = alpha_dynamic_entries_for_reloc (relent->rtype, dynamic,
@@ -3950,9 +3983,14 @@ elf64_alpha_size_rela_got_1 (h, info)
/* If the symbol is dynamic, we'll need all the relocations in their
natural form. If this is a shared object, and it has been forced
local, we'll need the same number of RELATIVE relocations. */
-
dynamic = alpha_elf_dynamic_symbol_p (&h->root, info);
+ /* If the symbol is a hidden undefined weak, then we never have any
+ relocations. Avoid the loop which may want to add RELATIVE relocs
+ based on info->shared. */
+ if (h->root.root.type == bfd_link_hash_undefweak && !dynamic)
+ return TRUE;
+
entries = 0;
for (gotent = h->got_entries; gotent ; gotent = gotent->next)
if (gotent->use_count > 0)
@@ -4445,7 +4483,7 @@ elf64_alpha_relocate_section (output_bfd, info, input_bfd, input_section,
/* If the symbol has been forced local, output a
RELATIVE reloc, otherwise it will be handled in
finish_dynamic_symbol. */
- if (info->shared && !dynamic_symbol_p)
+ if (info->shared && !dynamic_symbol_p && !undef_weak_ref)
elf64_alpha_emit_dynrel (output_bfd, info, sgot, srelgot,
gotent->got_offset, 0,
R_ALPHA_RELATIVE, value);
@@ -4617,7 +4655,8 @@ elf64_alpha_relocate_section (output_bfd, info, input_bfd, input_section,
}
else if (info->shared
&& r_symndx != 0
- && (input_section->flags & SEC_ALLOC))
+ && (input_section->flags & SEC_ALLOC)
+ && !undef_weak_ref)
{
if (r_type == R_ALPHA_REFLONG)
{
@@ -4650,6 +4689,14 @@ elf64_alpha_relocate_section (output_bfd, info, input_bfd, input_section,
input_bfd, h->root.root.root.string);
ret_val = FALSE;
}
+ else if ((info->shared || info->pie) && undef_weak_ref)
+ {
+ (*_bfd_error_handler)
+ (_("%B: pc-relative relocation against undefined weak symbol %s"),
+ input_bfd, h->root.root.root.string);
+ ret_val = FALSE;
+ }
+
/* ??? .eh_frame references to discarded sections will be smashed
to relocations against SHN_UNDEF. The .eh_frame format allows