From a8c4d40b578378be3b12575d127d4c7bd9972f32 Mon Sep 17 00:00:00 2001 From: "H.J. Lu" Date: Sun, 2 Feb 2020 17:07:51 -0800 Subject: ELF: Add support for unique section ID to assembler Clang's integrated assembler supports multiple section with the same name: .section .text,"ax",@progbits,unique,1 nop .section .text,"ax",@progbits,unique,2 nop "unique,N" assigns the number, N, as the section ID, to a section. The valid values of the section ID are between 0 and 4294967295. It can be used to distinguish different sections with the same section name. This is useful with -fno-unique-section-names -ffunction-sections. -ffunction-sections by default generates .text.foo, .text.bar, etc. Using the same string can save lots of space in .strtab. This patch adds section_id to bfd_section and reuses the linker internal bit in BFD section flags, SEC_LINKER_CREATED, for assmebler internal use to mark valid section_id. It also updates objdump to compare section pointers if 2 sections comes from the same file since 2 different sections can have the same section name. bfd/ PR gas/25380 * bfd-in2.h: Regenerated. * ecoff.c (bfd_debug_section): Add section_id. * section.c (bfd_section): Add section_id. (SEC_ASSEMBLER_SECTION_ID): New. (BFD_FAKE_SECTION): Add section_id. binutils/ PR gas/25380 * objdump.c (sym_ok): Return FALSE if 2 sections are in the same file with different section pointers. gas/ PR gas/25380 * config/obj-elf.c (section_match): Removed. (get_section): Also match SEC_ASSEMBLER_SECTION_ID and section_id. (obj_elf_change_section): Replace info and group_name arguments with match_p. Also update the section ID and flags from match_p. (obj_elf_section): Handle "unique,N". Update call to obj_elf_change_section. * config/obj-elf.h (elf_section_match): New. (obj_elf_change_section): Updated. * config/tc-arm.c (start_unwind_section): Update call to obj_elf_change_section. * config/tc-ia64.c (obj_elf_vms_common): Likewise. * config/tc-microblaze.c (microblaze_s_data): Likewise. (microblaze_s_sdata): Likewise. (microblaze_s_rdata): Likewise. (microblaze_s_bss): Likewise. * config/tc-mips.c (s_change_section): Likewise. * config/tc-msp430.c (msp430_profiler): Likewise. * config/tc-rx.c (parse_rx_section): Likewise. * config/tc-tic6x.c (tic6x_start_unwind_section): Likewise. * doc/as.texi: Document "unique,N" in .section directive. * testsuite/gas/elf/elf.exp: Run "unique,N" tests. * testsuite/gas/elf/section15.d: New file. * testsuite/gas/elf/section15.s: Likewise. * testsuite/gas/elf/section16.s: Likewise. * testsuite/gas/elf/section16a.d: Likewise. * testsuite/gas/elf/section16b.d: Likewise. * testsuite/gas/elf/section17.d: Likewise. * testsuite/gas/elf/section17.l: Likewise. * testsuite/gas/elf/section17.s: Likewise. * testsuite/gas/i386/unique.d: Likewise. * testsuite/gas/i386/unique.s: Likewise. * testsuite/gas/i386/x86-64-unique.d: Likewise. * testsuite/gas/i386/i386.exp: Run unique and x86-64-unique. ld/ PR gas/25380 * testsuite/ld-i386/pr22001-1c.S: Use "unique,N" in .section directives. * testsuite/ld-i386/tls-gd1.S: Likewise. * testsuite/ld-x86-64/pr21481b.S: Likewise. --- binutils/ChangeLog | 6 ++++++ binutils/objdump.c | 7 +++++++ 2 files changed, 13 insertions(+) (limited to 'binutils') diff --git a/binutils/ChangeLog b/binutils/ChangeLog index 222ea7a..a7fd431 100644 --- a/binutils/ChangeLog +++ b/binutils/ChangeLog @@ -1,3 +1,9 @@ +2020-02-02 H.J. Lu + + PR gas/25380 + * objdump.c (sym_ok): Return FALSE if 2 sections are in the + same file with different section pointers. + 2020-02-01 Nick Clifton * README-how-to-make-a-release: Update with more details on the diff --git a/binutils/objdump.c b/binutils/objdump.c index 60a3967..17c0637 100644 --- a/binutils/objdump.c +++ b/binutils/objdump.c @@ -1065,6 +1065,13 @@ sym_ok (bfd_boolean want_section, { if (want_section) { + /* NB: An object file can have different sections with the same + section name. Compare compare section pointers if they have + the same owner. */ + if (sorted_syms[place]->section->owner == sec->owner + && sorted_syms[place]->section != sec) + return FALSE; + /* Note - we cannot just compare section pointers because they could be different, but the same... Ie the symbol that we are trying to find could have come from a separate debug info file. Under such -- cgit v1.1