From 0572433b5beb636de1a49ec6b4fdab830c38cdc5 Mon Sep 17 00:00:00 2001 From: Alan Modra Date: Wed, 14 Jun 2017 10:47:25 +0930 Subject: PowerPC64 ELFv2 PPC64_OPT_LOCALENTRY ELFv2 functions with localentry:0 are those with a single entry point, ie. global entry == local entry, that have no requirement on r2 or r12 and guarantee r2 is unchanged on return. Such an external function can be called via the PLT without saving r2 or restoring it on return, avoiding a common load-hit-store for small functions. This patch implements the ld.so changes necessary for this optimization. ld.so needs to check that an optimized plt call sequence is in fact calling a function implemented with localentry:0, end emit a fatal error otherwise. The elf/testobj6.c change is to stop "error while loading shared libraries: expected localentry:0 `preload'" when running elf/preloadtest, which we'd get otherwise. * elf/elf.h (PPC64_OPT_LOCALENTRY): Define. * sysdeps/alpha/dl-machine.h (elf_machine_fixup_plt): Add refsym and sym parameters. Adjust callers. * sysdeps/aarch64/dl-machine.h (elf_machine_fixup_plt): Likewise. * sysdeps/arm/dl-machine.h (elf_machine_fixup_plt): Likewise. * sysdeps/generic/dl-machine.h (elf_machine_fixup_plt): Likewise. * sysdeps/hppa/dl-machine.h (elf_machine_fixup_plt): Likewise. * sysdeps/i386/dl-machine.h (elf_machine_fixup_plt): Likewise. * sysdeps/ia64/dl-machine.h (elf_machine_fixup_plt): Likewise. * sysdeps/m68k/dl-machine.h (elf_machine_fixup_plt): Likewise. * sysdeps/microblaze/dl-machine.h (elf_machine_fixup_plt): Likewise. * sysdeps/mips/dl-machine.h (elf_machine_fixup_plt): Likewise. * sysdeps/nios2/dl-machine.h (elf_machine_fixup_plt): Likewise. * sysdeps/powerpc/powerpc32/dl-machine.h (elf_machine_fixup_plt): Likewise. * sysdeps/s390/s390-32/dl-machine.h (elf_machine_fixup_plt): Likewise. * sysdeps/s390/s390-64/dl-machine.h (elf_machine_fixup_plt): Likewise. * sysdeps/sh/dl-machine.h (elf_machine_fixup_plt): Likewise. * sysdeps/sparc/sparc32/dl-machine.h (elf_machine_fixup_plt): Likewise. * sysdeps/sparc/sparc64/dl-machine.h (elf_machine_fixup_plt): Likewise. * sysdeps/tile/dl-machine.h (elf_machine_fixup_plt): Likewise. * sysdeps/x86_64/dl-machine.h (elf_machine_fixup_plt): Likewise. * sysdeps/powerpc/powerpc64/dl-machine.c (_dl_error_localentry): New. (_dl_reloc_overflow): Increase buffser size. Formatting. * sysdeps/powerpc/powerpc64/dl-machine.h (ppc64_local_entry_offset): Delete reloc param, add refsym and sym. Check optimized plt call stubs for localentry:0 functions. Adjust callers. (elf_machine_fixup_plt, elf_machine_plt_conflict): Add refsym and sym parameters. Adjust callers. (_dl_reloc_overflow): Move attribute. (_dl_error_localentry): Declare. * elf/dl-runtime.c (_dl_fixup): Save original sym. Pass refsym and sym to elf_machine_fixup_plt. * elf/testobj6.c (preload): Call printf. --- sysdeps/sparc/sparc32/dl-machine.h | 1 + sysdeps/sparc/sparc64/dl-machine.h | 1 + 2 files changed, 2 insertions(+) (limited to 'sysdeps/sparc') diff --git a/sysdeps/sparc/sparc32/dl-machine.h b/sysdeps/sparc/sparc32/dl-machine.h index 95f673270e..436e4e6cc3 100644 --- a/sysdeps/sparc/sparc32/dl-machine.h +++ b/sysdeps/sparc/sparc32/dl-machine.h @@ -294,6 +294,7 @@ _dl_start_user:\n\ static inline Elf32_Addr elf_machine_fixup_plt (struct link_map *map, lookup_t t, + const ElfW(Sym) *refsym, const ElfW(Sym) *sym, const Elf32_Rela *reloc, Elf32_Addr *reloc_addr, Elf32_Addr value) { diff --git a/sysdeps/sparc/sparc64/dl-machine.h b/sysdeps/sparc/sparc64/dl-machine.h index 1b59d78a25..c2871dca3a 100644 --- a/sysdeps/sparc/sparc64/dl-machine.h +++ b/sysdeps/sparc/sparc64/dl-machine.h @@ -85,6 +85,7 @@ elf_machine_load_address (void) static inline Elf64_Addr __attribute__ ((always_inline)) elf_machine_fixup_plt (struct link_map *map, lookup_t t, + const ElfW(Sym) *refsym, const ElfW(Sym) *sym, const Elf64_Rela *reloc, Elf64_Addr *reloc_addr, Elf64_Addr value) { -- cgit v1.2.3