From ae296cc45258b95223210263d1b91115e84beb56 Mon Sep 17 00:00:00 2001 From: mengqinggang Date: Mon, 11 Dec 2023 16:08:20 +0800 Subject: LoongArch: Add support for TLS LD/GD/DESC relaxation The pcalau12i + addi.d of TLS LD/GD/DESC relax to pcaddi. Relaxation is only performed when the TLS model transition is not possible. --- bfd/bfd-in2.h | 3 + bfd/elfnn-loongarch.c | 174 ++++++++++++++++++++++++++++++++++++++++++++++---- bfd/elfxx-loongarch.c | 60 +++++++++++++++++ bfd/libbfd.h | 3 + bfd/reloc.c | 7 ++ 5 files changed, 236 insertions(+), 11 deletions(-) (limited to 'bfd') diff --git a/bfd/bfd-in2.h b/bfd/bfd-in2.h index 85251aa..7828459 100644 --- a/bfd/bfd-in2.h +++ b/bfd/bfd-in2.h @@ -7473,6 +7473,9 @@ enum bfd_reloc_code_real BFD_RELOC_LARCH_TLS_DESC64_HI12, BFD_RELOC_LARCH_TLS_DESC_LD, BFD_RELOC_LARCH_TLS_DESC_CALL, + BFD_RELOC_LARCH_TLS_LD_PCREL20_S2, + BFD_RELOC_LARCH_TLS_GD_PCREL20_S2, + BFD_RELOC_LARCH_TLS_DESC_PCREL20_S2, BFD_RELOC_UNUSED }; typedef enum bfd_reloc_code_real bfd_reloc_code_real_type; diff --git a/bfd/elfnn-loongarch.c b/bfd/elfnn-loongarch.c index 1347d13..bd448cd 100644 --- a/bfd/elfnn-loongarch.c +++ b/bfd/elfnn-loongarch.c @@ -2285,7 +2285,9 @@ perform_relocation (const Elf_Internal_Rela *rel, asection *input_section, case R_LARCH_TLS_DESC_LO12: case R_LARCH_TLS_DESC64_LO20: case R_LARCH_TLS_DESC64_HI12: - + case R_LARCH_TLS_LD_PCREL20_S2: + case R_LARCH_TLS_GD_PCREL20_S2: + case R_LARCH_TLS_DESC_PCREL20_S2: r = loongarch_check_offset (rel, input_section); if (r != bfd_reloc_ok) break; @@ -3674,6 +3676,9 @@ loongarch_elf_relocate_section (bfd *output_bfd, struct bfd_link_info *info, case R_LARCH_TLS_GD_HI20: case R_LARCH_TLS_DESC_PC_HI20: case R_LARCH_TLS_DESC_HI20: + case R_LARCH_TLS_LD_PCREL20_S2: + case R_LARCH_TLS_GD_PCREL20_S2: + case R_LARCH_TLS_DESC_PCREL20_S2: BFD_ASSERT (rel->r_addend == 0); unresolved_reloc = false; @@ -3682,7 +3687,8 @@ loongarch_elf_relocate_section (bfd *output_bfd, struct bfd_link_info *info, is_ie = true; if (r_type == R_LARCH_TLS_DESC_PC_HI20 - || r_type == R_LARCH_TLS_DESC_HI20) + || r_type == R_LARCH_TLS_DESC_HI20 + || r_type == R_LARCH_TLS_DESC_PCREL20_S2) is_desc = true; bfd_vma got_off = 0; @@ -3813,7 +3819,11 @@ loongarch_elf_relocate_section (bfd *output_bfd, struct bfd_link_info *info, || r_type == R_LARCH_TLS_IE_PC_HI20 || r_type == R_LARCH_TLS_DESC_PC_HI20) RELOCATE_CALC_PC32_HI20 (relocation, pc); - + else if (r_type == R_LARCH_TLS_LD_PCREL20_S2 + || r_type == R_LARCH_TLS_GD_PCREL20_S2 + || r_type == R_LARCH_TLS_DESC_PCREL20_S2) + relocation -= pc; + /* else {} ABS relocations. */ break; case R_LARCH_TLS_DESC_PC_LO12: @@ -4244,6 +4254,85 @@ loongarch_relax_align (bfd *abfd, asection *sec, addend - need_nop_bytes, link_info); } +/* Relax pcalau12i + addi.d of TLS LD/GD/DESC to pcaddi. */ +static bool +loongarch_relax_tls_ld_gd_desc (bfd *abfd, asection *sec, asection *sym_sec, + Elf_Internal_Rela *rel_hi, bfd_vma symval, + struct bfd_link_info *info, bool *again) +{ + bfd_byte *contents = elf_section_data (sec)->this_hdr.contents; + Elf_Internal_Rela *rel_lo = rel_hi + 2; + uint32_t pca = bfd_get (32, abfd, contents + rel_hi->r_offset); + uint32_t add = bfd_get (32, abfd, contents + rel_lo->r_offset); + uint32_t rd = pca & 0x1f; + + /* This section's output_offset need to subtract the bytes of instructions + relaxed by the previous sections, so it needs to be updated beforehand. + size_input_section already took care of updating it after relaxation, + so we additionally update once here. */ + sec->output_offset = sec->output_section->size; + bfd_vma pc = sec_addr (sec) + rel_hi->r_offset; + + /* If pc and symbol not in the same segment, add/sub segment alignment. + FIXME: if there are multiple readonly segments? */ + if (!(sym_sec->flags & SEC_READONLY)) + { + if (symval > pc) + pc -= info->maxpagesize; + else if (symval < pc) + pc += info->maxpagesize; + } + + const uint32_t addi_d = 0x02c00000; + const uint32_t pcaddi = 0x18000000; + + /* Is pcalau12i + addi.d insns? */ + if ((ELFNN_R_TYPE (rel_lo->r_info) != R_LARCH_GOT_PC_LO12 + && ELFNN_R_TYPE (rel_lo->r_info) != R_LARCH_TLS_DESC_PC_LO12) + || (ELFNN_R_TYPE ((rel_lo + 1)->r_info) != R_LARCH_RELAX) + || (ELFNN_R_TYPE ((rel_hi + 1)->r_info) != R_LARCH_RELAX) + || (rel_hi->r_offset + 4 != rel_lo->r_offset) + || ((add & addi_d) != addi_d) + /* Is pcalau12i $rd + addi.d $rd,$rd? */ + || ((add & 0x1f) != rd) + || (((add >> 5) & 0x1f) != rd) + /* Can be relaxed to pcaddi? */ + || (symval & 0x3) /* 4 bytes align. */ + || ((bfd_signed_vma)(symval - pc) < (bfd_signed_vma)(int32_t)0xffe00000) + || ((bfd_signed_vma)(symval - pc) > (bfd_signed_vma)(int32_t)0x1ffffc)) + return false; + + /* Continue next relax trip. */ + *again = true; + + pca = pcaddi | rd; + bfd_put (32, abfd, pca, contents + rel_hi->r_offset); + + /* Adjust relocations. */ + switch (ELFNN_R_TYPE (rel_hi->r_info)) + { + case R_LARCH_TLS_LD_PC_HI20: + rel_hi->r_info = ELFNN_R_INFO (ELFNN_R_SYM (rel_hi->r_info), + R_LARCH_TLS_LD_PCREL20_S2); + break; + case R_LARCH_TLS_GD_PC_HI20: + rel_hi->r_info = ELFNN_R_INFO (ELFNN_R_SYM (rel_hi->r_info), + R_LARCH_TLS_GD_PCREL20_S2); + break; + case R_LARCH_TLS_DESC_PC_HI20: + rel_hi->r_info = ELFNN_R_INFO (ELFNN_R_SYM (rel_hi->r_info), + R_LARCH_TLS_DESC_PCREL20_S2); + break; + default: + break; + } + rel_lo->r_info = ELFNN_R_INFO (0, R_LARCH_NONE); + + loongarch_relax_delete_bytes (abfd, sec, rel_lo->r_offset, 4, info); + + return true; +} + static bool loongarch_elf_relax_section (bfd *abfd, asection *sec, struct bfd_link_info *info, @@ -4288,15 +4377,23 @@ loongarch_elf_relax_section (bfd *abfd, asection *sec, for (unsigned int i = 0; i < sec->reloc_count; i++) { - Elf_Internal_Rela *rel = relocs + i; - asection *sym_sec; + char symtype; bfd_vma symval; - unsigned long r_symndx = ELFNN_R_SYM (rel->r_info); - unsigned long r_type = ELFNN_R_TYPE (rel->r_info); + asection *sym_sec; bool local_got = false; - char symtype; + Elf_Internal_Rela *rel = relocs + i; struct elf_link_hash_entry *h = NULL; + unsigned long r_type = ELFNN_R_TYPE (rel->r_info); + unsigned long r_symndx = ELFNN_R_SYM (rel->r_info); + /* Four kind of relocations: + Normal: symval is the symbol address. + R_LARCH_ALIGN: symval is the address of the last NOP instruction + added by this relocation, and then adds 4 more. + R_LARCH_CALL36: symval is the symbol address for local symbols, + or the PLT entry address of the symbol. (Todo) + R_LARCHL_TLS_LD/GD/DESC_PC_HI20: symval is the GOT entry address + of the symbol. */ if (r_symndx < symtab_hdr->sh_info) { Elf_Internal_Sym *sym = (Elf_Internal_Sym *)symtab_hdr->contents @@ -4304,7 +4401,24 @@ loongarch_elf_relax_section (bfd *abfd, asection *sec, if (ELF_ST_TYPE (sym->st_info) == STT_GNU_IFUNC) continue; - if (sym->st_shndx == SHN_UNDEF || R_LARCH_ALIGN == r_type) + if (R_LARCH_TLS_LD_PC_HI20 == r_type + || R_LARCH_TLS_GD_PC_HI20 == r_type + || R_LARCH_TLS_DESC_PC_HI20 == r_type) + { + if (loongarch_can_relax_tls (info, r_type, h, abfd, r_symndx)) + continue; + else + { + sym_sec = htab->elf.sgot; + symval = elf_local_got_offsets (abfd)[r_symndx]; + char tls_type = _bfd_loongarch_elf_tls_type (abfd, h, + r_symndx); + if (R_LARCH_TLS_DESC_PC_HI20 == r_type + && GOT_TLS_GD_BOTH_P (tls_type)) + symval += 2 * GOT_ENTRY_SIZE; + } + } + else if (sym->st_shndx == SHN_UNDEF || R_LARCH_ALIGN == r_type) { sym_sec = sec; symval = rel->r_offset; @@ -4329,7 +4443,26 @@ loongarch_elf_relax_section (bfd *abfd, asection *sec, if (h != NULL && h->type == STT_GNU_IFUNC) continue; - if ((h->root.type == bfd_link_hash_defined + /* The GOT entry of tls symbols must in current execute file or + shared object. */ + if (R_LARCH_TLS_LD_PC_HI20 == r_type + || R_LARCH_TLS_GD_PC_HI20 == r_type + || R_LARCH_TLS_DESC_PC_HI20 == r_type) + { + if (loongarch_can_relax_tls (info, r_type, h, abfd, r_symndx)) + continue; + else + { + sym_sec = htab->elf.sgot; + symval = h->got.offset; + char tls_type = _bfd_loongarch_elf_tls_type (abfd, h, + r_symndx); + if (R_LARCH_TLS_DESC_PC_HI20 == r_type + && GOT_TLS_GD_BOTH_P (tls_type)) + symval += 2 * GOT_ENTRY_SIZE; + } + } + else if ((h->root.type == bfd_link_hash_defined || h->root.type == bfd_link_hash_defweak) && h->root.u.def.section != NULL && h->root.u.def.section->output_section != NULL) @@ -4358,7 +4491,7 @@ loongarch_elf_relax_section (bfd *abfd, asection *sec, if (symtype != STT_SECTION) symval += rel->r_addend; } - /* For R_LARCH_ALIGN, symval is sec_addr (sym_sec) + rel->r_offset + /* For R_LARCH_ALIGN, symval is sec_addr (sec) + rel->r_offset + (alingmeng - 4). If r_symndx is 0, alignmeng-4 is r_addend. If r_symndx > 0, alignment-4 is 2^(r_addend & 0xff)-4. */ @@ -4399,6 +4532,25 @@ loongarch_elf_relax_section (bfd *abfd, asection *sec, info, again); } break; + + case R_LARCH_TLS_LD_PC_HI20: + if (0 == info->relax_pass && (i + 4) <= sec->reloc_count) + loongarch_relax_tls_ld_gd_desc (abfd, sec, sym_sec, rel, symval, + info, again); + break; + + case R_LARCH_TLS_GD_PC_HI20: + if (0 == info->relax_pass && (i + 4) <= sec->reloc_count) + loongarch_relax_tls_ld_gd_desc (abfd, sec, sym_sec, rel, symval, + info, again); + break; + + case R_LARCH_TLS_DESC_PC_HI20: + if (0 == info->relax_pass && (i + 4) <= sec->reloc_count) + loongarch_relax_tls_ld_gd_desc (abfd, sec, sym_sec, rel, symval, + info, again); + break; + default: break; } diff --git a/bfd/elfxx-loongarch.c b/bfd/elfxx-loongarch.c index 30a941a..310e6d6 100644 --- a/bfd/elfxx-loongarch.c +++ b/bfd/elfxx-loongarch.c @@ -1775,6 +1775,60 @@ static loongarch_reloc_howto_type loongarch_howto_table[] = BFD_RELOC_LARCH_TLS_DESC_CALL, /* bfd_reloc_code_real_type. */ NULL, /* adjust_reloc_bits. */ "desc_call"), /* larch_reloc_type_name. */ + + /* For pcaddi, ld_pc_hi20 + ld_pc_lo12 can relax to ld_pcrel20_s2. */ + LOONGARCH_HOWTO (R_LARCH_TLS_LD_PCREL20_S2, /* type (124). */ + 2, /* rightshift. */ + 4, /* size. */ + 20, /* bitsize. */ + false, /* pc_relative. */ + 5, /* bitpos. */ + complain_overflow_signed, /* complain_on_overflow. */ + bfd_elf_generic_reloc, /* special_function. */ + "R_LARCH_TLS_LD_PCREL20_S2", /* name. */ + false, /* partial_inplace. */ + 0, /* src_mask. */ + 0x1ffffe0, /* dst_mask. */ + true, /* pcrel_offset. */ + BFD_RELOC_LARCH_TLS_LD_PCREL20_S2, /* bfd_reloc_code_real_type. */ + reloc_sign_bits, /* adjust_reloc_bits. */ + "ld_pcrel_20"), /* larch_reloc_type_name. */ + + /* For pcaddi, gd_pc_hi20 + gd_pc_lo12 can relax to gd_pcrel20_s2. */ + LOONGARCH_HOWTO (R_LARCH_TLS_GD_PCREL20_S2, /* type (125). */ + 2, /* rightshift. */ + 4, /* size. */ + 20, /* bitsize. */ + false, /* pc_relative. */ + 5, /* bitpos. */ + complain_overflow_signed, /* complain_on_overflow. */ + bfd_elf_generic_reloc, /* special_function. */ + "R_LARCH_TLS_GD_PCREL20_S2", /* name. */ + false, /* partial_inplace. */ + 0, /* src_mask. */ + 0x1ffffe0, /* dst_mask. */ + true, /* pcrel_offset. */ + BFD_RELOC_LARCH_TLS_GD_PCREL20_S2, /* bfd_reloc_code_real_type. */ + reloc_sign_bits, /* adjust_reloc_bits. */ + "gd_pcrel_20"), /* larch_reloc_type_name. */ + + /* For pcaddi, desc_pc_hi20 + desc_pc_lo12 can relax to desc_pcrel20_s2. */ + LOONGARCH_HOWTO (R_LARCH_TLS_DESC_PCREL20_S2, /* type (126). */ + 2, /* rightshift. */ + 4, /* size. */ + 20, /* bitsize. */ + false, /* pc_relative. */ + 5, /* bitpos. */ + complain_overflow_signed, /* complain_on_overflow. */ + bfd_elf_generic_reloc, /* special_function. */ + "R_LARCH_TLS_DESC_PCREL20_S2", /* name. */ + false, /* partial_inplace. */ + 0, /* src_mask. */ + 0x1ffffe0, /* dst_mask. */ + true, /* pcrel_offset. */ + BFD_RELOC_LARCH_TLS_DESC_PCREL20_S2, /* bfd_reloc_code_real_type. */ + reloc_sign_bits, /* adjust_reloc_bits. */ + "desc_pcrel_20"), /* larch_reloc_type_name. */ }; reloc_howto_type * @@ -1783,7 +1837,9 @@ loongarch_elf_rtype_to_howto (bfd *abfd, unsigned int r_type) if(r_type < R_LARCH_count) { /* For search table fast. */ + /* BFD_ASSERT (ARRAY_SIZE (loongarch_howto_table) == R_LARCH_count); + */ if (loongarch_howto_table[r_type].howto.type == r_type) return (reloc_howto_type *)&loongarch_howto_table[r_type]; @@ -1802,7 +1858,9 @@ loongarch_elf_rtype_to_howto (bfd *abfd, unsigned int r_type) reloc_howto_type * loongarch_reloc_name_lookup (bfd *abfd ATTRIBUTE_UNUSED, const char *r_name) { + /* BFD_ASSERT (ARRAY_SIZE (loongarch_howto_table) == R_LARCH_count); + */ for (size_t i = 0; i < ARRAY_SIZE (loongarch_howto_table); i++) if (loongarch_howto_table[i].howto.name @@ -1821,7 +1879,9 @@ reloc_howto_type * loongarch_reloc_type_lookup (bfd *abfd ATTRIBUTE_UNUSED, bfd_reloc_code_real_type code) { + /* BFD_ASSERT (ARRAY_SIZE (loongarch_howto_table) == R_LARCH_count); + */ /* Fast search for new reloc types. */ if (BFD_RELOC_LARCH_B16 <= code && code < BFD_RELOC_LARCH_RELAX) diff --git a/bfd/libbfd.h b/bfd/libbfd.h index 71b03da..8dab441 100644 --- a/bfd/libbfd.h +++ b/bfd/libbfd.h @@ -3612,6 +3612,9 @@ static const char *const bfd_reloc_code_real_names[] = { "@@uninitialized@@", "BFD_RELOC_LARCH_TLS_DESC64_HI12", "BFD_RELOC_LARCH_TLS_DESC_LD", "BFD_RELOC_LARCH_TLS_DESC_CALL", + "BFD_RELOC_LARCH_TLS_LD_PCREL20_S2", + "BFD_RELOC_LARCH_TLS_GD_PCREL20_S2", + "BFD_RELOC_LARCH_TLS_DESC_PCREL20_S2", "@@overflow: BFD_RELOC_UNUSED@@", }; #endif diff --git a/bfd/reloc.c b/bfd/reloc.c index f7fe0c7..6fd0f1f 100644 --- a/bfd/reloc.c +++ b/bfd/reloc.c @@ -8324,6 +8324,13 @@ ENUMX ENUMX BFD_RELOC_LARCH_TLS_DESC_CALL +ENUMX + BFD_RELOC_LARCH_TLS_LD_PCREL20_S2 +ENUMX + BFD_RELOC_LARCH_TLS_GD_PCREL20_S2 +ENUMX + BFD_RELOC_LARCH_TLS_DESC_PCREL20_S2 + ENUMDOC LARCH relocations. -- cgit v1.1