From f5b9c288a3057f0f04e74f00fdb0e79d171d54a8 Mon Sep 17 00:00:00 2001 From: Alan Modra Date: Tue, 2 Mar 2021 21:22:31 +1030 Subject: [PATCH] PowerPC64 undefined weak visibility vs GOT optimisation Undefined weak symbols with non-default visibility are seen as local by SYMBOL_REFERENCES_LOCAL. This stops a got indirect to relative optimisation for them, so that pies and dlls don't get non-zero values when loading somewhere other than the address they are linked at (which always happens). The optimisation could be allowed for pdes, but I thought it best not to allow it there too. bfd/ * elf64-ppc.c (ppc64_elf_relocate_section): Don't optimise got indirect to pc-relative or toc-relative for undefined symbols. ld/ * testsuite/ld-powerpc/weak1.d, * testsuite/ld-powerpc/weak1.r, * testsuite/ld-powerpc/weak1.s, * testsuite/ld-powerpc/weak1so.d, * testsuite/ld-powerpc/weak1so.r: New tests. * testsuite/ld-powerpc/powerpc.exp: Run them. --- bfd/ChangeLog | 5 +++++ bfd/elf64-ppc.c | 9 +++++++++ ld/ChangeLog | 9 +++++++++ ld/testsuite/ld-powerpc/powerpc.exp | 6 ++++++ ld/testsuite/ld-powerpc/weak1.d | 26 ++++++++++++++++++++++++++ ld/testsuite/ld-powerpc/weak1.r | 5 +++++ ld/testsuite/ld-powerpc/weak1.s | 22 ++++++++++++++++++++++ ld/testsuite/ld-powerpc/weak1so.d | 26 ++++++++++++++++++++++++++ ld/testsuite/ld-powerpc/weak1so.r | 7 +++++++ 9 files changed, 115 insertions(+) create mode 100644 ld/testsuite/ld-powerpc/weak1.d create mode 100644 ld/testsuite/ld-powerpc/weak1.r create mode 100644 ld/testsuite/ld-powerpc/weak1.s create mode 100644 ld/testsuite/ld-powerpc/weak1so.d create mode 100644 ld/testsuite/ld-powerpc/weak1so.r diff --git a/bfd/ChangeLog b/bfd/ChangeLog index 818f580e359..44286c2195d 100644 --- a/bfd/ChangeLog +++ b/bfd/ChangeLog @@ -1,3 +1,8 @@ +2021-03-02 Alan Modra + + * elf64-ppc.c (ppc64_elf_relocate_section): Don't optimise got + indirect to pc-relative or toc-relative for undefined symbols. + 2021-03-01 Alan Modra Fangrui Song diff --git a/bfd/elf64-ppc.c b/bfd/elf64-ppc.c index dcd427b3831..769fff9bb5c 100644 --- a/bfd/elf64-ppc.c +++ b/bfd/elf64-ppc.c @@ -16081,6 +16081,9 @@ ppc64_elf_relocate_section (bfd *output_bfd, break; from = TOCstart + htab->sec_info[input_section->id].toc_off; if (relocation + addend - from + 0x8000 < 0x10000 + && sec != NULL + && sec->output_section != NULL + && !discarded_section (sec) && (h == NULL || SYMBOL_REFERENCES_LOCAL (info, &h->elf))) { insn = bfd_get_32 (input_bfd, contents + (rel->r_offset & ~3)); @@ -16101,6 +16104,9 @@ ppc64_elf_relocate_section (bfd *output_bfd, break; from = TOCstart + htab->sec_info[input_section->id].toc_off; if (relocation + addend - from + 0x80008000ULL < 0x100000000ULL + && sec != NULL + && sec->output_section != NULL + && !discarded_section (sec) && (h == NULL || SYMBOL_REFERENCES_LOCAL (info, &h->elf))) { insn = bfd_get_32 (input_bfd, contents + (rel->r_offset & ~3)); @@ -16129,6 +16135,9 @@ ppc64_elf_relocate_section (bfd *output_bfd, + input_section->output_section->vma + input_section->output_offset); if (!(relocation - from + (1ULL << 33) < 1ULL << 34 + && sec != NULL + && sec->output_section != NULL + && !discarded_section (sec) && (h == NULL || SYMBOL_REFERENCES_LOCAL (info, &h->elf)))) break; diff --git a/ld/ChangeLog b/ld/ChangeLog index e43f7fa17a6..2bb97bd2809 100644 --- a/ld/ChangeLog +++ b/ld/ChangeLog @@ -1,3 +1,12 @@ +2021-03-02 Alan Modra + + * testsuite/ld-powerpc/weak1.d, + * testsuite/ld-powerpc/weak1.r, + * testsuite/ld-powerpc/weak1.s, + * testsuite/ld-powerpc/weak1so.d, + * testsuite/ld-powerpc/weak1so.r: New tests. + * testsuite/ld-powerpc/powerpc.exp: Run them. + 2021-03-01 Hannes Domani Nick Clifton diff --git a/ld/testsuite/ld-powerpc/powerpc.exp b/ld/testsuite/ld-powerpc/powerpc.exp index 45485e6c5d1..8aa0eccfa0e 100644 --- a/ld/testsuite/ld-powerpc/powerpc.exp +++ b/ld/testsuite/ld-powerpc/powerpc.exp @@ -344,6 +344,12 @@ set ppc64elftests { {"group3" "-melf64ppc -e foo" "" "-a64" {group3.s group2.s group1.s} {{objdump {-d} group2.d} {readelf {-s} group3.sym}} "group3"} + {"weak1" "-melf64ppc --hash-style=both" "" + "-a64 -mpower10" {weak1.s} + {{objdump -d weak1.d} {readelf {-srW} weak1.r}} "weak1"} + {"weak1.so" "-shared -melf64ppc --hash-style=both" "" + "-a64 -mpower10" {weak1.s} + {{objdump -d weak1so.d} {readelf {-srW} weak1so.r}} "weak1.so"} } set ppceabitests { diff --git a/ld/testsuite/ld-powerpc/weak1.d b/ld/testsuite/ld-powerpc/weak1.d new file mode 100644 index 00000000000..c0127539ddd --- /dev/null +++ b/ld/testsuite/ld-powerpc/weak1.d @@ -0,0 +1,26 @@ + +.*: file format .* + +Disassembly of section \.text: + +.*0c0 <_start>: +.*0c0: (04 10 00 01|01 00 10 04) pld r3,65888 +.*0c4: (e4 60 01 60|60 01 60 e4) +.*0c8: (04 10 00 01|01 00 10 04) pld r3,65856 +.*0cc: (e4 60 01 40|40 01 60 e4) +.*0d0: (04 10 00 01|01 00 10 04) pld r3,65864 +.*0d4: (e4 60 01 48|48 01 60 e4) +.*0d8: (04 10 00 01|01 00 10 04) pld r3,65848 +.*0dc: (e4 60 01 38|38 01 60 e4) +.*0e0: (e8 62 80 20|20 80 62 e8) ld r3,-32736\(r2\) +.*0e4: (e8 62 80 08|08 80 62 e8) ld r3,-32760\(r2\) +.*0e8: (e8 62 80 18|18 80 62 e8) ld r3,-32744\(r2\) +.*0ec: (e8 62 80 10|10 80 62 e8) ld r3,-32752\(r2\) +.*0f0: (60 00 00 00|00 00 00 60) nop +.*0f4: (e8 62 80 20|20 80 62 e8) ld r3,-32736\(r2\) +.*0f8: (60 00 00 00|00 00 00 60) nop +.*0fc: (e8 62 80 08|08 80 62 e8) ld r3,-32760\(r2\) +.*100: (60 00 00 00|00 00 00 60) nop +.*104: (e8 62 80 18|18 80 62 e8) ld r3,-32744\(r2\) +.*108: (60 00 00 00|00 00 00 60) nop +.*10c: (e8 62 80 10|10 80 62 e8) ld r3,-32752\(r2\) diff --git a/ld/testsuite/ld-powerpc/weak1.r b/ld/testsuite/ld-powerpc/weak1.r new file mode 100644 index 00000000000..7d73f38cbb3 --- /dev/null +++ b/ld/testsuite/ld-powerpc/weak1.r @@ -0,0 +1,5 @@ + +There are no relocations in this file. + +Symbol table '\.symtab' .* +#pass diff --git a/ld/testsuite/ld-powerpc/weak1.s b/ld/testsuite/ld-powerpc/weak1.s new file mode 100644 index 00000000000..0f370d974ba --- /dev/null +++ b/ld/testsuite/ld-powerpc/weak1.s @@ -0,0 +1,22 @@ + .weak x1, x2, x3, x4 + .protected x2 + .hidden x3 + .internal x4 + .global _start +_start: + pld 3,x1@got@pcrel + pld 3,x2@got@pcrel + pld 3,x3@got@pcrel + pld 3,x4@got@pcrel + ld 3,x1@got(2) + ld 3,x2@got(2) + ld 3,x3@got(2) + ld 3,x4@got(2) + addis 9,2,x1@got@ha + ld 3,x1@got@l(9) + addis 9,2,x2@got@ha + ld 3,x2@got@l(9) + addis 9,2,x3@got@ha + ld 3,x3@got@l(9) + addis 9,2,x4@got@ha + ld 3,x4@got@l(9) diff --git a/ld/testsuite/ld-powerpc/weak1so.d b/ld/testsuite/ld-powerpc/weak1so.d new file mode 100644 index 00000000000..0d34b3b4840 --- /dev/null +++ b/ld/testsuite/ld-powerpc/weak1so.d @@ -0,0 +1,26 @@ + +.*: file format .* + +Disassembly of section \.text: + +0+1c0 <_start>: + 1c0: (04 10 00 01|01 00 10 04) pld r3,66144 + 1c4: (e4 60 02 60|60 02 60 e4) + 1c8: (04 10 00 01|01 00 10 04) pld r3,66112 + 1cc: (e4 60 02 40|40 02 60 e4) + 1d0: (04 10 00 01|01 00 10 04) pld r3,66120 + 1d4: (e4 60 02 48|48 02 60 e4) + 1d8: (04 10 00 01|01 00 10 04) pld r3,66104 + 1dc: (e4 60 02 38|38 02 60 e4) + 1e0: (e8 62 80 20|20 80 62 e8) ld r3,-32736\(r2\) + 1e4: (e8 62 80 08|08 80 62 e8) ld r3,-32760\(r2\) + 1e8: (e8 62 80 18|18 80 62 e8) ld r3,-32744\(r2\) + 1ec: (e8 62 80 10|10 80 62 e8) ld r3,-32752\(r2\) + 1f0: (60 00 00 00|00 00 00 60) nop + 1f4: (e8 62 80 20|20 80 62 e8) ld r3,-32736\(r2\) + 1f8: (60 00 00 00|00 00 00 60) nop + 1fc: (e8 62 80 08|08 80 62 e8) ld r3,-32760\(r2\) + 200: (60 00 00 00|00 00 00 60) nop + 204: (e8 62 80 18|18 80 62 e8) ld r3,-32744\(r2\) + 208: (60 00 00 00|00 00 00 60) nop + 20c: (e8 62 80 10|10 80 62 e8) ld r3,-32752\(r2\) diff --git a/ld/testsuite/ld-powerpc/weak1so.r b/ld/testsuite/ld-powerpc/weak1so.r new file mode 100644 index 00000000000..dcc91f1879a --- /dev/null +++ b/ld/testsuite/ld-powerpc/weak1so.r @@ -0,0 +1,7 @@ +#... +.* R_PPC64_GLOB_DAT +0+ x1 \+ 0 +#... +.* 0+ +0 NOTYPE +WEAK +DEFAULT +UND x1 +#... +.* 0+ +0 NOTYPE +WEAK +DEFAULT +UND x1 +#pass -- 2.30.2