From 2f340668a9a7c00f8813b097b157b07fba8cfa82 Mon Sep 17 00:00:00 2001 From: Jiong Wang Date: Wed, 20 Jan 2016 16:57:59 +0000 Subject: [PATCH] [AArch64] Relax long branch veneer insertion for non STT_FUNC symbol As defined at AArch64 ELF Specification (4.6.7 Call and Jump relocations), symbol with type of non STT_FUNC but in different input section with relocation place should insert long branch veneer also. Meanwhile the current long branch veneer infrastructure havn't considered the situation where the branch destination is "sym_value + rela->addend". This was OK because we only insert veneer for long call destination is STT_FUNC symbol for which the addend is always zero. But as we relax the support to other situations by this patch, we need to handle addend be non-zero value. For example, for static function, relocation against "local symbol" are turned into relocation against "section symbol + offset" where there is a valid addend. bfd/ * elfnn-aarch64.c (aarch64_type_of_stub): Allow insert long branch veneer for sym_sec != input_sec. (elfNN_aarch64_size_stub): Support STT_SECTION symbol. (elfNN_aarch64_final_link_relocate): Take rela addend into account when calculation destination. ld/ * testsuite/ld-aarch64/farcall-section.d: Delete. * testsuite/ld-aarch64/farcall-section.s: Delete. * testsuite/ld-aarch64/farcall-b-section.d: New expectation file. * testsuite/ld-aarch64/farcall-bl-section.d: Likewise. * testsuite/ld-aarch64/farcall-b-section.s: New testcase. * testsuite/ld-aarch64/farcall-bl-section.s: Likewise. * testsuite/ld-aarch64/aarch64-elf.exp: Likewise. --- bfd/ChangeLog | 8 +++++ bfd/elfnn-aarch64.c | 25 ++++++++++---- ld/ChangeLog | 10 ++++++ ld/testsuite/ld-aarch64/aarch64-elf.exp | 3 +- .../ld-aarch64/farcall-b-none-function.d | 21 +++++++++++- ld/testsuite/ld-aarch64/farcall-b-section.d | 34 +++++++++++++++++++ ld/testsuite/ld-aarch64/farcall-b-section.s | 20 +++++++++++ .../ld-aarch64/farcall-bl-none-function.d | 21 +++++++++++- ld/testsuite/ld-aarch64/farcall-bl-section.d | 34 +++++++++++++++++++ ld/testsuite/ld-aarch64/farcall-bl-section.s | 20 +++++++++++ ld/testsuite/ld-aarch64/farcall-section.d | 5 --- ld/testsuite/ld-aarch64/farcall-section.s | 19 ----------- 12 files changed, 187 insertions(+), 33 deletions(-) create mode 100644 ld/testsuite/ld-aarch64/farcall-b-section.d create mode 100644 ld/testsuite/ld-aarch64/farcall-b-section.s create mode 100644 ld/testsuite/ld-aarch64/farcall-bl-section.d create mode 100644 ld/testsuite/ld-aarch64/farcall-bl-section.s delete mode 100644 ld/testsuite/ld-aarch64/farcall-section.d delete mode 100644 ld/testsuite/ld-aarch64/farcall-section.s diff --git a/bfd/ChangeLog b/bfd/ChangeLog index dcf21ce020..c4fd0bbffe 100644 --- a/bfd/ChangeLog +++ b/bfd/ChangeLog @@ -1,3 +1,11 @@ +2016-01-21 Jiong Wang + + * elfnn-aarch64.c (aarch64_type_of_stub): Allow insert long branch + veneer for sym_sec != input_sec. + (elfNN_aarch64_size_stub): Support STT_SECTION symbol. + (elfNN_aarch64_final_link_relocate): Take rela addend into account when + calculation destination. + 2016-01-21 Alan Modra * elf-linux-core.h (swap_linux_prpsinfo32_out): New function. diff --git a/bfd/elfnn-aarch64.c b/bfd/elfnn-aarch64.c index 70251f1d52..292470df73 100644 --- a/bfd/elfnn-aarch64.c +++ b/bfd/elfnn-aarch64.c @@ -2655,7 +2655,7 @@ aarch64_type_of_stub (struct bfd_link_info *info, bfd_boolean via_plt_p; if (st_type != STT_FUNC - && (sym_sec != bfd_abs_section_ptr)) + && (sym_sec == input_sec)) return stub_type; globals = elf_aarch64_hash_table (info); @@ -4174,7 +4174,7 @@ elfNN_aarch64_size_stubs (bfd *output_bfd, goto error_ret_free_internal; } - stub_entry->target_value = sym_value; + stub_entry->target_value = sym_value + irela->r_addend; stub_entry->target_section = sym_sec; stub_entry->stub_type = stub_type; stub_entry->h = hash; @@ -5280,15 +5280,28 @@ elfNN_aarch64_final_link_relocate (reloc_howto_type *howto, /* Check if a stub has to be inserted because the destination is too far away. */ struct elf_aarch64_stub_hash_entry *stub_entry = NULL; - if (! aarch64_valid_branch_p (value, place)) + + /* If the branch destination is directed to plt stub, "value" will be + the final destination, otherwise we should plus signed_addend, it may + contain non-zero value, for example call to local function symbol + which are turned into "sec_sym + sec_off", and sec_off is kept in + signed_addend. */ + if (! aarch64_valid_branch_p (via_plt_p ? value : value + signed_addend, + place)) /* The target is out of reach, so redirect the branch to the local stub for this function. */ stub_entry = elfNN_aarch64_get_stub_entry (input_section, sym_sec, h, rel, globals); if (stub_entry != NULL) - value = (stub_entry->stub_offset - + stub_entry->stub_sec->output_offset - + stub_entry->stub_sec->output_section->vma); + { + value = (stub_entry->stub_offset + + stub_entry->stub_sec->output_offset + + stub_entry->stub_sec->output_section->vma); + + /* We have redirected the destination to stub entry address, + so ignore any addend record in the original rela entry. */ + signed_addend = 0; + } } value = _bfd_aarch64_elf_resolve_relocation (bfd_r_type, place, value, signed_addend, weak_undef_p); diff --git a/ld/ChangeLog b/ld/ChangeLog index fc01ed6161..a6494b89c3 100644 --- a/ld/ChangeLog +++ b/ld/ChangeLog @@ -1,3 +1,13 @@ +2016-01-20 Jiong Wang + + * testsuite/ld-aarch64/farcall-section.d: Delete. + * testsuite/ld-aarch64/farcall-section.s: Delete. + * testsuite/ld-aarch64/farcall-b-section.d: New expectation file. + * testsuite/ld-aarch64/farcall-bl-section.d: Likewise. + * testsuite/ld-aarch64/farcall-b-section.s: New testcase. + * testsuite/ld-aarch64/farcall-bl-section.s: Likewise. + * testsuite/ld-aarch64/aarch64-elf.exp: Likewise. + 2016-01-20 Nick Clifton PR 19457 diff --git a/ld/testsuite/ld-aarch64/aarch64-elf.exp b/ld/testsuite/ld-aarch64/aarch64-elf.exp index c5c9ad0e97..939539ec80 100644 --- a/ld/testsuite/ld-aarch64/aarch64-elf.exp +++ b/ld/testsuite/ld-aarch64/aarch64-elf.exp @@ -170,7 +170,6 @@ run_dump_test "pcrel_pic_defined_local" run_dump_test "limit-b" run_dump_test "limit-bl" -run_dump_test "farcall-section" run_dump_test "farcall-back" run_dump_test "farcall-b-defsym" run_dump_test "farcall-bl-defsym" @@ -181,6 +180,8 @@ run_dump_test "farcall-bl" run_dump_test "farcall-b" run_dump_test "farcall-b-none-function" run_dump_test "farcall-bl-none-function" +run_dump_test "farcall-b-section" +run_dump_test "farcall-bl-section" run_dump_test "tls-relax-all" run_dump_test "tls-relax-gd-le" diff --git a/ld/testsuite/ld-aarch64/farcall-b-none-function.d b/ld/testsuite/ld-aarch64/farcall-b-none-function.d index 34a6568dfb..ba2981fb10 100644 --- a/ld/testsuite/ld-aarch64/farcall-b-none-function.d +++ b/ld/testsuite/ld-aarch64/farcall-b-none-function.d @@ -2,4 +2,23 @@ #source: farcall-b-none-function.s #as: #ld: -Ttext 0x1000 --section-start .foo=0x8001000 -#error: .*\(.text\+0x0\): relocation truncated to fit: R_AARCH64_JUMP26 against symbol `bar'.* +#objdump: -dr +#... + +Disassembly of section .text: + +.* <_start>: + 1000: 14000003 b 100c <__bar_veneer> + 1004: d65f03c0 ret + 1008: 14000007 b 1024 <__bar_veneer\+0x18> + +.* <__bar_veneer>: + 100c: 90040010 adrp x16, 8001000 + 1010: 91000210 add x16, x16, #0x0 + 1014: d61f0200 br x16 + ... + +Disassembly of section .foo: + +.* : + 8001000: d65f03c0 ret diff --git a/ld/testsuite/ld-aarch64/farcall-b-section.d b/ld/testsuite/ld-aarch64/farcall-b-section.d new file mode 100644 index 0000000000..4745c0f24f --- /dev/null +++ b/ld/testsuite/ld-aarch64/farcall-b-section.d @@ -0,0 +1,34 @@ +#name: aarch64-farcall-b-section +#source: farcall-b-section.s +#as: +#ld: -Ttext 0x1000 --section-start .foo=0x8001000 +#objdump: -dr +#... + +Disassembly of section .text: + +.* <_start>: + 1000: 14000008 b 1020 <___veneer> + 1004: 14000003 b 1010 <___veneer> + 1008: d65f03c0 ret + 100c: 1400000d b 1040 <___veneer\+0x20> + +.* <___veneer>: + 1010: 90040010 adrp x16, 8001000 + 1014: 91001210 add x16, x16, #0x4 + 1018: d61f0200 br x16 + 101c: 00000000 .inst 0x00000000 ; undefined + +.* <___veneer>: + 1020: 90040010 adrp x16, 8001000 + 1024: 91000210 add x16, x16, #0x0 + 1028: d61f0200 br x16 + ... + +Disassembly of section .foo: + +.* : + 8001000: d65f03c0 ret + +.* : + 8001004: d65f03c0 ret diff --git a/ld/testsuite/ld-aarch64/farcall-b-section.s b/ld/testsuite/ld-aarch64/farcall-b-section.s new file mode 100644 index 0000000000..1a135ef339 --- /dev/null +++ b/ld/testsuite/ld-aarch64/farcall-b-section.s @@ -0,0 +1,20 @@ +.global _start + +# We will place the section .text at 0x1000. + + .text + +_start: + b bar + b bar2 + ret + +# We will place the section .foo at 0x8001000. + + .section .foo, "xa" + .type bar, @function +bar: + ret + .type bar2, @function +bar2: + ret diff --git a/ld/testsuite/ld-aarch64/farcall-bl-none-function.d b/ld/testsuite/ld-aarch64/farcall-bl-none-function.d index 6ce9ca45b2..b6a4ddae44 100644 --- a/ld/testsuite/ld-aarch64/farcall-bl-none-function.d +++ b/ld/testsuite/ld-aarch64/farcall-bl-none-function.d @@ -2,4 +2,23 @@ #source: farcall-bl-none-function.s #as: #ld: -Ttext 0x1000 --section-start .foo=0x8001000 -#error: .*\(.text\+0x0\): relocation truncated to fit: R_AARCH64_CALL26 against symbol `bar'.* +#objdump: -dr +#... + +Disassembly of section .text: + +.* <_start>: + 1000: 94000003 bl 100c <__bar_veneer> + 1004: d65f03c0 ret + 1008: 14000007 b 1024 <__bar_veneer\+0x18> + +.* <__bar_veneer>: + 100c: 90040010 adrp x16, 8001000 + 1010: 91000210 add x16, x16, #0x0 + 1014: d61f0200 br x16 + ... + +Disassembly of section .foo: + +.* : + 8001000: d65f03c0 ret diff --git a/ld/testsuite/ld-aarch64/farcall-bl-section.d b/ld/testsuite/ld-aarch64/farcall-bl-section.d new file mode 100644 index 0000000000..2bd4f85e70 --- /dev/null +++ b/ld/testsuite/ld-aarch64/farcall-bl-section.d @@ -0,0 +1,34 @@ +#name: aarch64-farcall-bl-section +#source: farcall-bl-section.s +#as: +#ld: -Ttext 0x1000 --section-start .foo=0x8001000 +#objdump: -dr +#... + +Disassembly of section .text: + +.* <_start>: + 1000: 94000008 bl 1020 <___veneer> + 1004: 94000003 bl 1010 <___veneer> + 1008: d65f03c0 ret + 100c: 1400000d b 1040 <___veneer\+0x20> + +.* <___veneer>: + 1010: 90040010 adrp x16, 8001000 + 1014: 91001210 add x16, x16, #0x4 + 1018: d61f0200 br x16 + 101c: 00000000 .inst 0x00000000 ; undefined + +.* <___veneer>: + 1020: 90040010 adrp x16, 8001000 + 1024: 91000210 add x16, x16, #0x0 + 1028: d61f0200 br x16 + ... + +Disassembly of section .foo: + +.* : + 8001000: d65f03c0 ret + +.* : + 8001004: d65f03c0 ret diff --git a/ld/testsuite/ld-aarch64/farcall-bl-section.s b/ld/testsuite/ld-aarch64/farcall-bl-section.s new file mode 100644 index 0000000000..4469d4dd34 --- /dev/null +++ b/ld/testsuite/ld-aarch64/farcall-bl-section.s @@ -0,0 +1,20 @@ + .global _start + +# We will place the section .text at 0x1000. + + .text + +_start: + bl bar + bl bar2 + ret + +# We will place the section .foo at 0x8001000. + + .section .foo, "xa" + .type bar, @function +bar: + ret + .type bar2, @function +bar2: + ret diff --git a/ld/testsuite/ld-aarch64/farcall-section.d b/ld/testsuite/ld-aarch64/farcall-section.d deleted file mode 100644 index 85775e1a65..0000000000 --- a/ld/testsuite/ld-aarch64/farcall-section.d +++ /dev/null @@ -1,5 +0,0 @@ -#name: Aarch64 farcall to symbol of type STT_SECTION -#source: farcall-section.s -#as: -#ld: -Ttext 0x1000 --section-start .foo=0x8001014 -#error: .*\(.text\+0x0\): relocation truncated to fit: R_AARCH64_CALL26 against `.foo' diff --git a/ld/testsuite/ld-aarch64/farcall-section.s b/ld/testsuite/ld-aarch64/farcall-section.s deleted file mode 100644 index 86a070c7c2..0000000000 --- a/ld/testsuite/ld-aarch64/farcall-section.s +++ /dev/null @@ -1,19 +0,0 @@ -# Test to ensure that an Aarch64 call exceeding 128MB generates an error -# if the destination is of type STT_SECTION (eg non-global symbol) - - .global _start - -# We will place the section .text at 0x1000. - - .text - -_start: - bl bar - -# We will place the section .foo at 0x8001020. - - .section .foo, "xa" - -bar: - ret -