From: Alan Modra <amodra@gmail.com>
Date: Thu, 16 Apr 2020 01:13:25 +0000 (+0930)
Subject: PowerPC64 GOT reloc optimisation
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=06507dab6172582d3924a3d7dc92a9e7d4ab60ff;p=binutils-gdb.git

PowerPC64 GOT reloc optimisation

When the symbol referenced by a GOT reloc is an ifunc, we can't
optimise away the GOT indirection.  Well, we can, but only if a global
entry stub is created with the ifunc symbol redefined to the stub.
But that results in slower code and an indirection via the PLT so
there isn't much to like about that solution.

	* elf64-ppc.c (ppc64_elf_edit_toc): Exclude ifunc from GOT
	optimisation.
	(ppc64_elf_relocate_section): Likewise.
---

diff --git a/bfd/elf64-ppc.c b/bfd/elf64-ppc.c
index 945f83c7e61..25a3e468a73 100644
--- a/bfd/elf64-ppc.c
+++ b/bfd/elf64-ppc.c
@@ -9371,6 +9371,9 @@ ppc64_elf_edit_toc (struct bfd_link_info *info)
 		  || discarded_section (sym_sec))
 		continue;
 
+	      if ((h ? h->type : ELF_ST_TYPE (sym->st_info)) == STT_GNU_IFUNC)
+		continue;
+
 	      if (!SYMBOL_REFERENCES_LOCAL (info, h))
 		continue;
 
@@ -15886,6 +15889,8 @@ ppc64_elf_relocate_section (bfd *output_bfd,
 	  break;
 
 	case R_PPC64_GOT16_DS:
+	  if ((h ? h->elf.type : ELF_ST_TYPE (sym->st_info)) == STT_GNU_IFUNC)
+	    break;
 	  from = TOCstart + htab->sec_info[input_section->id].toc_off;
 	  if (relocation + addend - from + 0x8000 < 0x10000
 	      && SYMBOL_REFERENCES_LOCAL (info, &h->elf))
@@ -15903,6 +15908,8 @@ ppc64_elf_relocate_section (bfd *output_bfd,
 
 	case R_PPC64_GOT16_LO_DS:
 	case R_PPC64_GOT16_HA:
+	  if ((h ? h->elf.type : ELF_ST_TYPE (sym->st_info)) == STT_GNU_IFUNC)
+	    break;
 	  from = TOCstart + htab->sec_info[input_section->id].toc_off;
 	  if (relocation + addend - from + 0x80008000ULL < 0x100000000ULL
 	      && SYMBOL_REFERENCES_LOCAL (info, &h->elf))
@@ -15924,6 +15931,8 @@ ppc64_elf_relocate_section (bfd *output_bfd,
 	  break;
 
 	case R_PPC64_GOT_PCREL34:
+	  if ((h ? h->elf.type : ELF_ST_TYPE (sym->st_info)) == STT_GNU_IFUNC)
+	    break;
 	  from = (rel->r_offset
 		  + input_section->output_section->vma
 		  + input_section->output_offset);