Add ELFv2 .localentry support.

This defines the ELF symbol st_other field used to encode the number
of instructions between a function "global entry" and its "local entry",
and adds support related to the local entry offset.

include/elf/
	* ppc64.h (STO_PPC64_LOCAL_BIT, STO_PPC64_LOCAL_MASK): Define.
	(ppc64_decode_local_entry, ppc64_encode_local_entry): New functions.
	(PPC64_LOCAL_ENTRY_OFFSET, PPC64_SET_LOCAL_ENTRY_OFFSET): Define.
bfd/
	* elf64-ppc.c (struct ppc_stub_hash_entry): Add "other".
	(stub_hash_newfunc): Init new ppc_stub_hash_entry field, and one
	we forgot, "plt_ent".
	(ppc64_elf_add_symbol_hook): Check ELFv1 objects don't have
	st_other bits only valid in ELFv2.
	(ppc64_elf_merge_symbol_attribute): New function.
	(ppc_type_of_stub): Add local_off param to test branch range.
	(ppc_build_one_stub): Adjust destinations for ELFv2 locals.
	(ppc_size_one_stub, toc_adjusting_stub_needed): Similarly.
	(ppc64_elf_size_stubs): Pass local_off to ppc_type_of_stub.
	Set "other" field.
	(ppc64_elf_relocate_section): Adjust destination for ELFv2 local
	calls.
gas/
	* config/tc-ppc.c (md_pseudo_table): Add .localentry.
	(ppc_elf_localentry): New function.
	(ppc_force_relocation): Force relocs on all branches to localenty
	symbols.
	(ppc_fix_adjustable): Don't reduce such symbols to section+offset.
binutils/
	* readelf.c (get_ppc64_symbol_other): New function.
	(get_symbol_other): Use it for EM_PPC64.

1 files changed, 106 insertions, 0 deletions

diff --git a/gas/config/tc-ppc.c b/gas/config/tc-ppc.c
index c249cec..822f5a2 100644
--- a/gas/config/tc-ppc.c
+++ b/gas/config/tc-ppc.c
@@ -134,6 +134,7 @@ static void ppc_vbyte (int);
 static void ppc_elf_cons (int);
 static void ppc_elf_rdata (int);
 static void ppc_elf_lcomm (int);
+static void ppc_elf_localentry (int);
 static void ppc_elf_abiversion (int);
 #endif
 
@@ -266,6 +267,7 @@ const pseudo_typeS md_pseudo_table[] =
   { "rdata",	ppc_elf_rdata,	0 },
   { "rodata",	ppc_elf_rdata,	0 },
   { "lcomm",	ppc_elf_lcomm,	0 },
+  { "localentry", ppc_elf_localentry,	0 },
   { "abiversion", ppc_elf_abiversion,	0 },
 #endif
 
@@ -2226,6 +2228,68 @@ ppc_elf_lcomm (int xxx ATTRIBUTE_UNUSED)
   demand_empty_rest_of_line ();
 }
 
+/* Pseudo op to set symbol local entry point.  */
+static void
+ppc_elf_localentry (int ignore ATTRIBUTE_UNUSED)
+{
+  char *name = input_line_pointer;
+  char c = get_symbol_end ();
+  char *p;
+  expressionS exp;
+  symbolS *sym;
+  asymbol *bfdsym;
+  elf_symbol_type *elfsym;
+
+  p = input_line_pointer;
+  *p = c;
+  SKIP_WHITESPACE ();
+  if (*input_line_pointer != ',')
+    {
+      *p = 0;
+      as_bad (_("expected comma after name `%s' in .localentry directive"),
+	      name);
+      *p = c;
+      ignore_rest_of_line ();
+      return;
+    }
+  input_line_pointer++;
+  expression (&exp);
+  if (exp.X_op == O_absent)
+    {
+      as_bad (_("missing expression in .localentry directive"));
+      exp.X_op = O_constant;
+      exp.X_add_number = 0;
+    }
+  *p = 0;
+  sym = symbol_find_or_make (name);
+  *p = c;
+
+  if (resolve_expression (&exp)
+      && exp.X_op == O_constant)
+    {
+      unsigned char encoded = PPC64_SET_LOCAL_ENTRY_OFFSET (exp.X_add_number);
+
+      if (exp.X_add_number != PPC64_LOCAL_ENTRY_OFFSET (encoded))
+        as_bad (_(".localentry expression for `%s' "
+		  "is not a valid power of 2"), S_GET_NAME (sym));
+      else
+	{
+	  bfdsym = symbol_get_bfdsym (sym);
+	  elfsym = elf_symbol_from (bfd_asymbol_bfd (bfdsym), bfdsym);
+	  gas_assert (elfsym);
+	  elfsym->internal_elf_sym.st_other &= ~STO_PPC64_LOCAL_MASK;
+	  elfsym->internal_elf_sym.st_other |= encoded;
+	  if (ppc_abiversion == 0)
+	    ppc_abiversion = 2;
+	}
+    }
+  else
+    as_bad (_(".localentry expression for `%s' "
+	      "does not evaluate to a constant"), S_GET_NAME (sym));
+
+  demand_empty_rest_of_line ();
+}
+
 /* Pseudo op to set ABI version.  */
 static void
 ppc_elf_abiversion (int ignore ATTRIBUTE_UNUSED)
@@ -6229,6 +6293,22 @@ ppc_force_relocation (fixS *fix)
     case BFD_RELOC_24_PLT_PCREL:
     case BFD_RELOC_PPC64_TOC:
       return 1;
+    case BFD_RELOC_PPC_B26:
+    case BFD_RELOC_PPC_BA26:
+    case BFD_RELOC_PPC_B16:
+    case BFD_RELOC_PPC_BA16:
+      /* All branch fixups targeting a localentry symbol must
+         force a relocation.  */
+      if (fix->fx_addsy)
+	{
+	  asymbol *bfdsym = symbol_get_bfdsym (fix->fx_addsy);
+	  elf_symbol_type *elfsym
+	    = elf_symbol_from (bfd_asymbol_bfd (bfdsym), bfdsym);
+	  gas_assert (elfsym);
+	  if ((STO_PPC64_LOCAL_MASK & elfsym->internal_elf_sym.st_other) != 0)
+	    return 1;
+	}
+      break;
     default:
       break;
     }
@@ -6243,6 +6323,32 @@ ppc_force_relocation (fixS *fix)
 int
 ppc_fix_adjustable (fixS *fix)
 {
+  switch (fix->fx_r_type)
+    {
+      /* All branch fixups targeting a localentry symbol must
+         continue using the symbol.  */
+    case BFD_RELOC_PPC_B26:
+    case BFD_RELOC_PPC_BA26:
+    case BFD_RELOC_PPC_B16:
+    case BFD_RELOC_PPC_BA16:
+    case BFD_RELOC_PPC_B16_BRTAKEN:
+    case BFD_RELOC_PPC_B16_BRNTAKEN:
+    case BFD_RELOC_PPC_BA16_BRTAKEN:
+    case BFD_RELOC_PPC_BA16_BRNTAKEN:
+      if (fix->fx_addsy)
+	{
+	  asymbol *bfdsym = symbol_get_bfdsym (fix->fx_addsy);
+	  elf_symbol_type *elfsym
+	    = elf_symbol_from (bfd_asymbol_bfd (bfdsym), bfdsym);
+	  gas_assert (elfsym);
+	  if ((STO_PPC64_LOCAL_MASK & elfsym->internal_elf_sym.st_other) != 0)
+	    return 0;
+	}
+      break;
+    default:
+      break;
+    }
+
   return (fix->fx_r_type != BFD_RELOC_16_GOTOFF
 	  && fix->fx_r_type != BFD_RELOC_LO16_GOTOFF
 	  && fix->fx_r_type != BFD_RELOC_HI16_GOTOFF