BFD: Fix the bug of R_LARCH_AGLIN caused by discard section To represent the first and third expression of .align, R_LARCH_ALIGN need to associate with a symbol. We define a local symbol for R_LARCH_AGLIN. But if the section of the local symbol is discarded, it may result in a undefined symbol error. Instead, we use the section name symbols, and this does not need to add extra symbols. During partial linking (ld -r), if the symbol associated with a relocation is STT_SECTION type, the addend of relocation needs to add the section output offset. We prevent it for R_LARCH_ALIGN. The elf_backend_data.rela_normal only can set all relocations of a target to rela_normal. Add a new function is_rela_normal to elf_backend_data, it can set part of relocations to rela_normal.
diff --git a/bfd/elf-bfd.h b/bfd/elf-bfd.h index c5d3254..af507b9 100644 --- a/bfd/elf-bfd.h +++ b/bfd/elf-bfd.h
@@ -1721,6 +1721,10 @@ backend relocate_section routine for relocatable linking. */ unsigned rela_normal : 1; + /* Whether a relocation is rela_normal. Compared with rela_normal, + is_rela_normal can set part of relocations to rela_normal. */ + bool (*is_rela_normal) (Elf_Internal_Rela *); + /* Set if DT_REL/DT_RELA/DT_RELSZ/DT_RELASZ should not include PLT relocations. */ unsigned dtrel_excludes_plt : 1;
diff --git a/bfd/elflink.c b/bfd/elflink.c index 24eb30d..5d9b409 100644 --- a/bfd/elflink.c +++ b/bfd/elflink.c
@@ -11692,7 +11692,10 @@ { rel_hash = PTR_ADD (esdo->rela.hashes, esdo->rela.count); rela_hash_list = rel_hash; - rela_normal = bed->rela_normal; + if (bed->is_rela_normal != NULL) + rela_normal = bed->is_rela_normal (irela); + else + rela_normal = bed->rela_normal; } irela->r_offset = _bfd_elf_section_offset (output_bfd,
diff --git a/bfd/elfnn-loongarch.c b/bfd/elfnn-loongarch.c index c42052f..1679aa5 100644 --- a/bfd/elfnn-loongarch.c +++ b/bfd/elfnn-loongarch.c
@@ -5454,6 +5454,21 @@ return _bfd_elf_hash_symbol (h); } +/* If a relocation is rela_normal and the symbol associated with the + relocation is STT_SECTION type, the addend of the relocation would add + sec->output_offset when partial linking (ld -r). + See elf_backend_data.rela_normal and elf_link_input_bfd(). + The addend of R_LARCH_ALIGN is used to represent the first and third + expression of .align, it should be a constant when linking. */ + +static bool +loongarch_elf_is_rela_normal (Elf_Internal_Rela *rel) +{ + if (R_LARCH_ALIGN == ELFNN_R_TYPE (rel->r_info)) + return false; + return true; +} + #define TARGET_LITTLE_SYM loongarch_elfNN_vec #define TARGET_LITTLE_NAME "elfNN-loongarch" #define ELF_ARCH bfd_arch_loongarch @@ -5489,6 +5504,7 @@ #define elf_backend_grok_psinfo loongarch_elf_grok_psinfo #define elf_backend_hash_symbol elf_loongarch64_hash_symbol #define bfd_elfNN_bfd_relax_section loongarch_elf_relax_section +#define elf_backend_is_rela_normal loongarch_elf_is_rela_normal #define elf_backend_dtrel_excludes_plt 1
diff --git a/bfd/elfxx-target.h b/bfd/elfxx-target.h index 1e6992b..6e2d948 100644 --- a/bfd/elfxx-target.h +++ b/bfd/elfxx-target.h
@@ -709,6 +709,10 @@ #define elf_backend_rela_normal 0 #endif +#ifndef elf_backend_is_rela_normal +#define elf_backend_is_rela_normal NULL +#endif + #ifndef elf_backend_dtrel_excludes_plt #define elf_backend_dtrel_excludes_plt 0 #endif @@ -955,6 +959,7 @@ elf_backend_default_use_rela_p, elf_backend_rela_plts_and_copies_p, elf_backend_rela_normal, + elf_backend_is_rela_normal, elf_backend_dtrel_excludes_plt, elf_backend_sign_extend_vma, elf_backend_want_got_plt,
diff --git a/gas/config/tc-loongarch.c b/gas/config/tc-loongarch.c index 30aefce..6b1a897 100644 --- a/gas/config/tc-loongarch.c +++ b/gas/config/tc-loongarch.c
@@ -1791,10 +1791,7 @@ if (fragP->fr_subtype != 0 && offset > fragP->fr_subtype). */ if (max > 0 && (bfd_vma) max < worst_case_bytes) { - s = symbol_find (".Lla-relax-align"); - if (s == NULL) - s = (symbolS *)local_symbol_make (".Lla-relax-align", now_seg, - &zero_address_frag, 0); + s = symbol_find (now_seg->name); ex.X_add_symbol = s; ex.X_op = O_symbol; ex.X_add_number = (max << 8) | n;
diff --git a/gas/testsuite/gas/loongarch/relax_align.d b/gas/testsuite/gas/loongarch/relax_align.d index fc1fd03..acd215a 100644 --- a/gas/testsuite/gas/loongarch/relax_align.d +++ b/gas/testsuite/gas/loongarch/relax_align.d
@@ -7,7 +7,7 @@ Disassembly of section .text: -[ ]*0000000000000000 <.Lla-relax-align>: +[ ]*0000000000000000 <.text>: [ ]+0:[ ]+4c000020[ ]+ret [ ]+4:[ ]+03400000[ ]+nop [ ]+4: R_LARCH_ALIGN[ ]+\*ABS\*\+0xc @@ -20,12 +20,12 @@ [ ]+1c:[ ]+03400000[ ]+nop [ ]+20:[ ]+4c000020[ ]+ret [ ]+24:[ ]+03400000[ ]+nop -[ ]+24: R_LARCH_ALIGN[ ]+.Lla-relax-align\+0x104 +[ ]+24: R_LARCH_ALIGN[ ]+.text\+0x104 [ ]+28:[ ]+03400000[ ]+nop [ ]+2c:[ ]+03400000[ ]+nop [ ]+30:[ ]+4c000020[ ]+ret [ ]+34:[ ]+03400000[ ]+nop -[ ]+34: R_LARCH_ALIGN[ ]+.Lla-relax-align\+0xb04 +[ ]+34: R_LARCH_ALIGN[ ]+.text\+0xb04 [ ]+38:[ ]+03400000[ ]+nop [ ]+3c:[ ]+03400000[ ]+nop [ ]+40:[ ]+4c000020[ ]+ret
diff --git a/ld/testsuite/ld-loongarch-elf/relax-align-discard.lds b/ld/testsuite/ld-loongarch-elf/relax-align-discard.lds new file mode 100644 index 0000000..4a81323 --- /dev/null +++ b/ld/testsuite/ld-loongarch-elf/relax-align-discard.lds
@@ -0,0 +1,4 @@ +SECTIONS +{ + /DISCARD/ : { *(.another.*) } +}
diff --git a/ld/testsuite/ld-loongarch-elf/relax-align-discard.s b/ld/testsuite/ld-loongarch-elf/relax-align-discard.s new file mode 100644 index 0000000..b65d63f --- /dev/null +++ b/ld/testsuite/ld-loongarch-elf/relax-align-discard.s
@@ -0,0 +1,17 @@ +# Use the section name symbol for R_LARCH_ALIGN to avoid discard section problem +.section ".another.text", "ax" +.cfi_startproc +break 0 +.cfi_def_cfa_offset 16 +.p2align 5 +break 1 +.cfi_endproc + +.text +.cfi_startproc +break 0 +.cfi_def_cfa_offset 16 +.p2align 5 +break 1 +.cfi_endproc +
diff --git a/ld/testsuite/ld-loongarch-elf/relax.exp b/ld/testsuite/ld-loongarch-elf/relax.exp index 7d95a9c..ed71fb4 100644 --- a/ld/testsuite/ld-loongarch-elf/relax.exp +++ b/ld/testsuite/ld-loongarch-elf/relax.exp
@@ -295,6 +295,18 @@ "relax-align" \ ] \ ] + + run_ld_link_tests \ + [list \ + [list \ + "loongarch relax align discard" \ + "-e 0x0 -T relax-align-discard.lds -r" "" \ + "" \ + {relax-align-discard.s} \ + {} \ + "relax-align-discard" \ + ] \ + ] } set objdump_flags "-s -j .data"