aix: implement TLS relocation for gas and ld

Add support for TLS in XCOFF. Amongst the things done by this commit:
 - Update XCOFF auxialiary header to match new version and allow TLS
   sections.
 - Add TLS sections (.tdata and .tbss) support in gas and ld.
 - Add support for the TLS relocations in gas and ld.
   Two different types BFD_RELOC are created for PPC and PPC64 as
   the size is a pointer, thus distinct in 32 or 64bit.

The addresses given by ld to .tdata and .tbss is a bit special. In
XCOFF, these addresses are actually offsets from the TLS pointer
computed at runtime. AIX assembly and linker does the same. In
top of that, the .tdata must be before .data (this is mandatory for AIX
loader). Thus, the aix ld script is recomputing "." before .data to restore
its original value. There might be a simpler way, but this one is working.

Optimisation linked to TLS relocations aren't yet implemented.

bfd/
	* reloc.c (BFD_RELOC_PPC_TLS_LE, BFD_RELOC_PPC_TLS_IE,
	BFD_RELOC_PPC_TLS_M, BFD_RELOC_PPC_TLS_ML, BFD_RELOC_PPC64_TLS_GD,
	BFD_RELOC_PPC64_TLS_LD, BFD_RELOC_PPC64_TLS_LE,
	BFD_RELOC_PPC64_TLS_IE, BFD_RELOC_PPC64_TLS_M,
	BFD_RELOC_PPC64_TLS_ML): New relocations.
	* bfd-in2.h: Regenerate.
	* libbfd.h: Regenerate.
	* coff-rs6000.c (xcoff_calculate_relocation): Call
	xcoff_reloc_type_tls for TLS relocations.
	(xcoff_howto_table): Implement TLS relocations.
	(_bfd_xcoff_reloc_type_lookup): Add cases TLS relocations.
	(xcoff_reloc_type_tls): New function.
	* coff64-rs6000.c (xcoff_calculate_relocation): Likewise.
	(xcoff_howto_table): Likewise.
	(_bfd_xcoff_reloc_type_lookup): Likewise.
	* coffcode.h (sec_to_styp_flags): Handle TLS sections.
	(styp_to_sec_flags): Likewise.
	(coff_compute_section_file_positions): Avoid file offset
	optimisation for .data when the previous section is .tdata.
	(coff_write_object_contents): Handle TLS sections.
	* coffswap.h (coff_swap_aouthdr_out): Add support for
	new fields in aouthdr.
	* libxcoff.h (xcoff_reloc_type_tls): Add prototype.
	* xcofflink.c (xcoff_link_add_symbols): Handle XMC_UL.
	(xcoff_need_ldrel_p): Add cases for TLS relocations.
	(xcoff_create_ldrel): Add l_symndx for TLS sections.
gas/
	* config/tc-ppc.c (ppc_xcoff_text_section, ppc_xcoff_data_section,
	(ppc_xcoff_bss_section, ppc_xcoff_tdata_section,
	(ppc_xcoff_tbss_section): New variables.
	(ppc_text_subsegment, ppc_text_csects, ppc_data_subgments,
	(ppc_data_csects): Removed.
	(ppc_xcoff_section_is_initialized, ppc_init_xcoff_section,
	ppc_xcoff_parse_cons): New functions.
	(md_being): Initialize XCOFF sections.
	(ppc_xcoff_suffix): Add support for TLS relocations
	(fixup_size, md_apply_fix): Add support for new BFD_RELOC.
	(ppc_change_csect): Handle XMC_TL, XMC_UL.  Correctly, add XMC_BS
	to .bss section.  Handle new XCOFF section variables.
	(ppc_comm): Likewise.
	(ppc_toc): Likewise.
	(ppc_symbol_new_hook): Likewise.
	(ppc_frob_symbol): Likewise.
	(ppc_fix_adjustable): Add tbss support.
	* config/tc-ppc.h (TC_PARSE_CONS_EXPRESSION): New define.
	(ppc_xcoff_parse_cons): Add prototype.
	(struct ppc_xcoff_section): New structure.
ld/
	* emultempl/aix.em: Ensure .tdata section is removed
	if empty, even with -r flag.
	* scripttempl/aix.sc: Handle TLS sections.
	* testsuite/ld-powerpc/aix52.exp: Add new tests.
	* testsuite/ld-powerpc/aix-tls-reloc-32.d: New test.
	* testsuite/ld-powerpc/aix-tls-reloc-64.d: New test.
	* testsuite/ld-powerpc/aix-tls-reloc.ex: New test.
	* testsuite/ld-powerpc/aix-tls-reloc.s: New test.
	* testsuite/ld-powerpc/aix-tls-section-32.d: New test.
	* testsuite/ld-powerpc/aix-tls-section-64.d: New test.
	* testsuite/ld-powerpc/aix-tls-section.ex: New test.
	* testsuite/ld-powerpc/aix-tls-section.s: New test.
include/
	* coff/internal.h (struct internal_aouthdr): Add new fields.
	* coff/rs6000.h (AOUTHDRÃ): Add new fields.
	* coff/rs6k64.h (struct external_filehdr): Likewise.
	* coff/xcoff.h (_TDATA), _TBSS): New defines
	(RS6K_AOUTHDR_TLS_LE, RS6K_AOUTHDR_RAS, RS6K_AOUTHDR_ALGNTDATA,
	RS6K_AOUTHDR_SHR_SYMTAB, RS6K_AOUTHDR_FORK_POLICY,
	RS6K_AOUTHDR_FORK_COR): New defines.
	(XMC_TU): Removed.
	(XMC_UL): New define.

1 files changed, 198 insertions, 19 deletions

diff --git a/bfd/coff-rs6000.c b/bfd/coff-rs6000.c
index b77ff0c234a..a29cf5b958d 100644
--- a/bfd/coff-rs6000.c
+++ b/bfd/coff-rs6000.c
@@ -190,12 +190,12 @@ xcoff_calculate_relocation[XCOFF_MAX_CALCULATE_RELOCATION] =
   xcoff_reloc_type_fail, /*           (0x1d) */
   xcoff_reloc_type_fail, /*           (0x1e) */
   xcoff_reloc_type_fail, /*           (0x1f) */
-  xcoff_reloc_type_fail, /* R_TLS     (0x20) */
-  xcoff_reloc_type_fail, /* R_TLS_IE  (0x21) */
-  xcoff_reloc_type_fail, /* R_TLS_LD  (0x22) */
-  xcoff_reloc_type_fail, /* R_TLS_LE  (0x23) */
-  xcoff_reloc_type_fail, /* R_TLSM    (0x24) */
-  xcoff_reloc_type_fail, /* R_TLSML   (0x25) */
+  xcoff_reloc_type_tls,  /* R_TLS     (0x20) */
+  xcoff_reloc_type_tls,  /* R_TLS_IE  (0x21) */
+  xcoff_reloc_type_tls,  /* R_TLS_LD  (0x22) */
+  xcoff_reloc_type_tls,  /* R_TLS_LE  (0x23) */
+  xcoff_reloc_type_tls,  /* R_TLSM    (0x24) */
+  xcoff_reloc_type_tls,  /* R_TLSML   (0x25) */
   xcoff_reloc_type_fail, /*           (0x26) */
   xcoff_reloc_type_fail, /*           (0x27) */
   xcoff_reloc_type_fail, /*           (0x28) */
@@ -1064,22 +1064,95 @@ reloc_howto_type xcoff_howto_table[] =
   EMPTY_HOWTO (0x1f),
 
   /* 0x20: General-dynamic TLS relocation.  */
-  EMPTY_HOWTO (R_TLS),
+  HOWTO (R_TLS,			/* type */
+	 0,			/* rightshift */
+	 2,			/* size (0 = byte, 1 = short, 2 = long) */
+	 32,			/* bitsize */
+	 FALSE,			/* pc_relative */
+	 0,			/* bitpos */
+	 complain_overflow_bitfield, /* complain_on_overflow */
+	 0,			/* special_function */
+	 "R_TLS",		/* name */
+	 TRUE,			/* partial_inplace */
+	 0xffffffff,		/* src_mask */
+	 0xffffffff,		/* dst_mask */
+	 FALSE),		/* pcrel_offset */
 
   /* 0x21: Initial-exec TLS relocation.  */
-  EMPTY_HOWTO (R_TLS_IE),
+  HOWTO (R_TLS_IE,		/* type */
+	 0,			/* rightshift */
+	 2,			/* size (0 = byte, 1 = short, 2 = long) */
+	 32,			/* bitsize */
+	 FALSE,			/* pc_relative */
+	 0,			/* bitpos */
+	 complain_overflow_bitfield, /* complain_on_overflow */
+	 0,			/* special_function */
+	 "R_TLS_IE",		/* name */
+	 TRUE,			/* partial_inplace */
+	 0xffffffff,		/* src_mask */
+	 0xffffffff,		/* dst_mask */
+	 FALSE),		/* pcrel_offset */
 
   /* 0x22: Local-dynamic TLS relocation.  */
-  EMPTY_HOWTO (R_TLS_LD),
+  HOWTO (R_TLS_LD,		/* type */
+	 0,			/* rightshift */
+	 2,			/* size (0 = byte, 1 = short, 2 = long) */
+	 32,			/* bitsize */
+	 FALSE,			/* pc_relative */
+	 0,			/* bitpos */
+	 complain_overflow_bitfield, /* complain_on_overflow */
+	 0,			/* special_function */
+	 "R_TLS_LD",		/* name */
+	 TRUE,			/* partial_inplace */
+	 0xffffffff,		/* src_mask */
+	 0xffffffff,		/* dst_mask */
+	 FALSE),		/* pcrel_offset */
 
   /* 0x23: Local-exec TLS relocation.  */
-  EMPTY_HOWTO (R_TLS_LE),
+  HOWTO (R_TLS_LE,		/* type */
+	 0,			/* rightshift */
+	 2,			/* size (0 = byte, 1 = short, 2 = long) */
+	 32,			/* bitsize */
+	 FALSE,			/* pc_relative */
+	 0,			/* bitpos */
+	 complain_overflow_bitfield, /* complain_on_overflow */
+	 0,			/* special_function */
+	 "R_TLS_LE",		/* name */
+	 TRUE,			/* partial_inplace */
+	 0xffffffff,		/* src_mask */
+	 0xffffffff,		/* dst_mask */
+	 FALSE),		/* pcrel_offset */
 
   /* 0x24: TLS relocation.  */
-  EMPTY_HOWTO(R_TLSM),
+  HOWTO (R_TLSM,		/* type */
+	 0,			/* rightshift */
+	 2,			/* size (0 = byte, 1 = short, 2 = long) */
+	 32,			/* bitsize */
+	 FALSE,			/* pc_relative */
+	 0,			/* bitpos */
+	 complain_overflow_bitfield, /* complain_on_overflow */
+	 0,			/* special_function */
+	 "R_TLSM",		/* name */
+	 TRUE,			/* partial_inplace */
+	 0xffffffff,		/* src_mask */
+	 0xffffffff,		/* dst_mask */
+	 FALSE),		/* pcrel_offset */
+
 
   /* 0x25: TLS module relocation.  */
-  EMPTY_HOWTO(R_TLSML),
+  HOWTO (R_TLSML,		/* type */
+	 0,			/* rightshift */
+	 2,			/* size (0 = byte, 1 = short, 2 = long) */
+	 32,			/* bitsize */
+	 FALSE,			/* pc_relative */
+	 0,			/* bitpos */
+	 complain_overflow_bitfield, /* complain_on_overflow */
+	 0,			/* special_function */
+	 "R_TLSM",		/* name */
+	 TRUE,			/* partial_inplace */
+	 0xffffffff,		/* src_mask */
+	 0xffffffff,		/* dst_mask */
+	 FALSE),		/* pcrel_offset */
 
   EMPTY_HOWTO(0x26),
   EMPTY_HOWTO(0x27),
@@ -1180,6 +1253,18 @@ _bfd_xcoff_reloc_type_lookup (bfd *abfd ATTRIBUTE_UNUSED,
       return &xcoff_howto_table[0];
     case BFD_RELOC_NONE:
       return &xcoff_howto_table[0xf];
+    case BFD_RELOC_PPC_TLSGD:
+      return &xcoff_howto_table[0x20];
+    case BFD_RELOC_PPC_TLSIE:
+      return &xcoff_howto_table[0x21];
+    case BFD_RELOC_PPC_TLSLD:
+      return &xcoff_howto_table[0x22];
+    case BFD_RELOC_PPC_TLSLE:
+      return &xcoff_howto_table[0x23];
+    case BFD_RELOC_PPC_TLSM:
+      return &xcoff_howto_table[0x24];
+    case BFD_RELOC_PPC_TLSML:
+      return &xcoff_howto_table[0x25];
     default:
       return NULL;
     }
@@ -3127,6 +3212,88 @@ xcoff_reloc_type_crel (bfd *input_bfd ATTRIBUTE_UNUSED,
   return TRUE;
 }
 
+bfd_boolean
+xcoff_reloc_type_tls (bfd *input_bfd ATTRIBUTE_UNUSED,
+		      asection *input_section ATTRIBUTE_UNUSED,
+		      bfd *output_bfd ATTRIBUTE_UNUSED,
+		      struct internal_reloc *rel ATTRIBUTE_UNUSED,
+		      struct internal_syment *sym ATTRIBUTE_UNUSED,
+		      struct reloc_howto_struct *howto,
+		      bfd_vma val,
+		      bfd_vma addend,
+		      bfd_vma *relocation,
+		      bfd_byte *contents ATTRIBUTE_UNUSED)
+{
+  struct xcoff_link_hash_entry *h;
+
+  if (0 > rel->r_symndx)
+    return FALSE;
+
+  h = obj_xcoff_sym_hashes (input_bfd)[rel->r_symndx];
+
+  /* FIXME: R_TLSML is targeting a internal TOC symbol, which will
+     make the following checks failing. It should be moved with
+     R_TLSM bellow once it works.  */
+  if (howto->type == R_TLSML)
+    {
+      *relocation = 0;
+      return TRUE;
+    }
+
+  /* FIXME: h is sometimes null, if the TLS symbol is not exported.  */
+  if (!h)
+    {
+      _bfd_error_handler
+	(_("%pB: TLS relocation at (0x%" BFD_VMA_FMT "x) over "
+	   "internal symbols (C_HIDEXT) not yet possible\n"),
+	 input_bfd, rel->r_vaddr);
+      return FALSE;
+    }
+
+
+  /* TLS relocations must target a TLS symbol.  */
+  if (h->smclas != XMC_TL && h->smclas != XMC_UL)
+    {
+      _bfd_error_handler
+	(_("%pB: TLS relocation at (0x%" BFD_VMA_FMT "x) over "
+	   "non-TLS symbol %s (0x%x)\n"),
+	 input_bfd, rel->r_vaddr, h->root.root.string, h->smclas);
+      return FALSE;
+    }
+
+  /* Local TLS relocations must target a local symbol, ie
+     non-imported. */
+  if ((rel->r_type == R_TLS_LD || rel->r_type == R_TLS_LE)
+      && (((h->flags & XCOFF_DEF_REGULAR) == 0
+       && (h->flags & XCOFF_DEF_DYNAMIC) != 0)
+	  || (h->flags & XCOFF_IMPORT) != 0))
+    {
+      _bfd_error_handler
+	(_("%pB: TLS local relocation at (0x%" BFD_VMA_FMT "x) over "
+	   "imported symbol %s\n"),
+	 input_bfd, rel->r_vaddr, h->root.root.string);
+      return FALSE;
+    }
+
+  /* R_TLSM and R_TLSML are relocations used by the loader.
+     The value must be 0.
+     FIXME: move R_TLSML here.  */
+  if (howto->type == R_TLSM)
+    {
+      *relocation = 0;
+      return TRUE;
+    }
+
+  /* Other TLS relocations aims to put offsets from TLS pointers
+     starting at -0x7c00 (or -0x7800 in XCOFF64).  It becomes a
+     simple R_POS relocation as long as .tdata and .tbss addresses
+     start at the same value. This is done in aix ld scripts.
+     TODO: implement optimization when tls size is < 62K.  */
+  *relocation = val + addend;
+
+  return TRUE;
+}
+
 static bfd_boolean
 xcoff_complain_overflow_dont_func (bfd *input_bfd ATTRIBUTE_UNUSED,
 				   bfd_vma val ATTRIBUTE_UNUSED,
@@ -3335,13 +3502,6 @@ xcoff_complain_overflow_unsigned_func (bfd *input_bfd,
    quite figure out when this is useful.  These relocs are
    not defined by the PowerOpen ABI.
 
-   R_TLS
-   R_TLS_IE
-   R_TLS_LD
-   R_TLSLE
-
-   Not yet implemented.
-
    Supported r_type's
 
    R_POS:
@@ -3437,6 +3597,25 @@ xcoff_complain_overflow_unsigned_func (bfd *input_bfd,
    fixed address which may be modified to a relative branch.
    The PowerOpen ABI does not define this relocation type.
 
+   R_TLS:
+   Thread-local storage relocation using general-dynamic
+   model.
+
+   R_TLS_IE:
+   Thread-local storage relocation using initial-exec model.
+
+   R_TLS_LD:
+   Thread-local storage relocation using local-dynamic model.
+
+   R_TLS_LE:
+   Thread-local storage relocation using local-exec model.
+
+   R_TLS:
+   Tread-local storage relocation used by the loader.
+
+   R_TLSM:
+   Tread-local storage relocation used by the loader.
+
    R_TOCU:
    Upper TOC relative relocation. The value is the
    high-order 16 bit of a TOC relative relocation.