From d7ba245135934068e70fff46aa6a3f8f1f8737dd Mon Sep 17 00:00:00 2001 From: "H.J. Lu" Date: Thu, 24 Sep 2020 05:45:50 -0700 Subject: [PATCH] gas: Generate a new section for SHF_GNU_RETAIN For .globl foo2 .section .data.foo,"aR" .align 4 .type foo2, @object .size foo2, 4 foo2: .long 2 .globl foo1 .section .data.foo .align 4 .type foo1, @object .size foo1, 4 foo1: .long 1 generate a new section if the SHF_GNU_RETAIN bit doesn't match. * config/obj-elf.c (SEC_ASSEMBLER_SHF_MASK): New. (get_section_by_match): Also check if SEC_ASSEMBLER_SHF_MASK of sh_flags matches. Rename info to sh_info. (obj_elf_change_section): Don't check previous SHF_GNU_RETAIN. Rename info to sh_info. (obj_elf_section): Rename info to sh_info. Set sh_flags for SHF_GNU_RETAIN. * config/obj-elf.h (elf_section_match): Rename info to sh_info. Add sh_flags. * testsuite/gas/elf/elf.exp: Run section27. * testsuite/gas/elf/section24b.d: Updated. * testsuite/gas/elf/section27.d: New file. * testsuite/gas/elf/section27.s: Likewise. --- gas/config/obj-elf.c | 35 +++++++++++++++--------------- gas/config/obj-elf.h | 3 ++- gas/testsuite/gas/elf/elf.exp | 1 + gas/testsuite/gas/elf/section24b.d | 10 ++++++--- gas/testsuite/gas/elf/section27.d | 19 ++++++++++++++++ gas/testsuite/gas/elf/section27.s | 34 +++++++++++++++++++++++++++++ 6 files changed, 81 insertions(+), 21 deletions(-) create mode 100644 gas/testsuite/gas/elf/section27.d create mode 100644 gas/testsuite/gas/elf/section27.s diff --git a/gas/config/obj-elf.c b/gas/config/obj-elf.c index 54d42d9ecb..5d3b1a0edc 100644 --- a/gas/config/obj-elf.c +++ b/gas/config/obj-elf.c @@ -519,6 +519,9 @@ struct section_stack static struct section_stack *section_stack; +/* ELF section flags for unique sections. */ +#define SEC_ASSEMBLER_SHF_MASK SHF_GNU_RETAIN + /* Return TRUE iff SEC matches the section info INF. */ static bfd_boolean @@ -529,9 +532,12 @@ get_section_by_match (bfd *abfd ATTRIBUTE_UNUSED, asection *sec, void *inf) const char *group_name = elf_group_name (sec); const char *linked_to_symbol_name = sec->map_head.linked_to_symbol_name; - unsigned int info = elf_section_data (sec)->this_hdr.sh_info; + unsigned int sh_info = elf_section_data (sec)->this_hdr.sh_info; + bfd_vma sh_flags = (elf_section_data (sec)->this_hdr.sh_flags + & SEC_ASSEMBLER_SHF_MASK); - return (info == match->info + return (sh_info == match->sh_info + && sh_flags == match->sh_flags && ((bfd_section_flags (sec) & SEC_ASSEMBLER_SECTION_ID) == (match->flags & SEC_ASSEMBLER_SECTION_ID)) && sec->section_id == match->section_id @@ -740,7 +746,7 @@ obj_elf_change_section (const char *name, type = bfd_elf_get_default_section_type (flags); elf_section_type (sec) = type; elf_section_flags (sec) = attr; - elf_section_data (sec)->this_hdr.sh_info = match_p->info; + elf_section_data (sec)->this_hdr.sh_info = match_p->sh_info; /* Prevent SEC_HAS_CONTENTS from being inadvertently set. */ if (type == SHT_NOBITS) @@ -806,17 +812,9 @@ obj_elf_change_section (const char *name, as_bad (_("changed section attributes for %s"), name); } else - { - /* Don't overwrite a previously set SHF_GNU_RETAIN flag for the - section. The entire section must be marked retained. */ - if ((elf_tdata (stdoutput)->has_gnu_osabi & elf_gnu_osabi_retain) - && ((elf_section_flags (old_sec) & SHF_GNU_RETAIN))) - attr |= SHF_GNU_RETAIN; - - /* FIXME: Maybe we should consider removing a previously set - processor or application specific attribute as suspicious ? */ - elf_section_flags (sec) = attr; - } + /* FIXME: Maybe we should consider removing a previously set + processor or application specific attribute as suspicious? */ + elf_section_flags (sec) = attr; if ((flags & SEC_MERGE) && old_sec->entsize != (unsigned) entsize) as_bad (_("changed section entity size for %s"), name); @@ -1322,18 +1320,21 @@ obj_elf_section (int push) if (ISDIGIT (* input_line_pointer)) { char *t = input_line_pointer; - match.info = strtoul (input_line_pointer, + match.sh_info = strtoul (input_line_pointer, &input_line_pointer, 0); - if (match.info == (unsigned int) -1) + if (match.sh_info == (unsigned int) -1) { as_warn (_("unsupported mbind section info: %s"), t); - match.info = 0; + match.sh_info = 0; } } else input_line_pointer = save; } + if ((gnu_attr & SHF_GNU_RETAIN) != 0) + match.sh_flags |= SHF_GNU_RETAIN; + if (*input_line_pointer == ',') { char *save = input_line_pointer; diff --git a/gas/config/obj-elf.h b/gas/config/obj-elf.h index 4f29572eef..c714ba7a70 100644 --- a/gas/config/obj-elf.h +++ b/gas/config/obj-elf.h @@ -106,8 +106,9 @@ struct elf_section_match { const char * group_name; const char * linked_to_symbol_name; - unsigned int info; unsigned int section_id; + unsigned int sh_info; /* ELF section information. */ + bfd_vma sh_flags; /* ELF section flags. */ flagword flags; }; diff --git a/gas/testsuite/gas/elf/elf.exp b/gas/testsuite/gas/elf/elf.exp index 25c40a2810..80dec4effc 100644 --- a/gas/testsuite/gas/elf/elf.exp +++ b/gas/testsuite/gas/elf/elf.exp @@ -268,6 +268,7 @@ if { [is_elf_format] } then { run_dump_test "section24b" run_dump_test "section25" run_dump_test "section26" + run_dump_test "section27" run_dump_test "sh-link-zero" run_dump_test "dwarf2-1" $dump_opts run_dump_test "dwarf2-2" $dump_opts diff --git a/gas/testsuite/gas/elf/section24b.d b/gas/testsuite/gas/elf/section24b.d index 451ec21635..03dd2916ef 100644 --- a/gas/testsuite/gas/elf/section24b.d +++ b/gas/testsuite/gas/elf/section24b.d @@ -3,8 +3,12 @@ #source: section24.s #readelf: -S --wide -#failif #... - \[..\] .(text|data|bss|rodata)[ ]+PROGBITS[ ]+[0-9a-f]+ [0-9a-f]+ [0-9a-f]+ 00 [^R] .* + \[..\] .text[ ]+PROGBITS[ ]+[0-9a-f]+ [0-9a-f]+ [0-9a-f]+ 00 +AX .* +#... + \[..\] .data[ ]+PROGBITS[ ]+[0-9a-f]+ [0-9a-f]+ [0-9a-f]+ 00 +WA .* +#... + \[..\] .bss[ ]+NOBITS[ ]+[0-9a-f]+ [0-9a-f]+ [0-9a-f]+ 00 +WA .* +#... + \[..\] .rodata[ ]+PROGBITS[ ]+[0-9a-f]+ [0-9a-f]+ [0-9a-f]+ 00 +A .* #pass - diff --git a/gas/testsuite/gas/elf/section27.d b/gas/testsuite/gas/elf/section27.d new file mode 100644 index 0000000000..da0734fe84 --- /dev/null +++ b/gas/testsuite/gas/elf/section27.d @@ -0,0 +1,19 @@ +#readelf: -h -S --wide +#name: SHF_GNU_RETAIN sections 27 +#notarget: ![supports_gnu_osabi] + +#... + +OS/ABI: +UNIX - (GNU|FreeBSD) +#... + \[..\] .text[ ]+PROGBITS[ ]+[0-9a-f]+ [0-9a-f]+ [0-9a-f]+ 00 AX.* +#... + \[..\] .data[ ]+PROGBITS[ ]+[0-9a-f]+ [0-9a-f]+ [0-9a-f]+ 00 WA.* +#... + \[..\] .bss[ ]+NOBITS[ ]+[0-9a-f]+ [0-9a-f]+ [0-9a-f]+ 00 WA.* +#... + \[..\] .bss[ ]+NOBITS[ ]+[0-9a-f]+ [0-9a-f]+ [0-9a-f]+ 00 WAR.* +#... + \[..\] .data[ ]+PROGBITS[ ]+[0-9a-f]+ [0-9a-f]+ [0-9a-f]+ 00 WAR.* +#... + \[..\] .text[ ]+PROGBITS[ ]+[0-9a-f]+ [0-9a-f]+ [0-9a-f]+ 00 AXR.* +#pass diff --git a/gas/testsuite/gas/elf/section27.s b/gas/testsuite/gas/elf/section27.s new file mode 100644 index 0000000000..78e410ff95 --- /dev/null +++ b/gas/testsuite/gas/elf/section27.s @@ -0,0 +1,34 @@ + .section .bss,"aw" + .global discard0 + .type discard0, %object +discard0: + .zero 2 + + .section .data,"aw" + .global discard1 + .type discard1, %object +discard1: + .word 1 + + .text + .global discard2 + .type discard2, %function +discard2: + .word 0 + + .section .bss,"awR",%nobits + .global retain0 + .type retain0, %object +retain0: + .zero 2 + + .section .data,"awR",%progbits + .type retain1, %object +retain1: + .word 1 + + .section .text,"axR",%progbits + .global retain2 + .type retain2, %function +retain2: + .word 0 -- 2.29.2