[Committed] S/390: Make TLS work without -fpic

["Andreas Krebbel" <krebbel at linux dot vnet dot ibm dot com>]

Hi,

this fixes the tls testsuite fails on s390.  Calls to __tls_get_offset
require the GOT pointer to be loaded what so far only happened when
building pic code.  With the attached patch the GOT pointer is loaded
"on demand" when calling __tls_get_offset.

Committed to mainline.

Bye,

-Andreas-


2011-10-07  Andreas Krebbel  <Andreas.Krebbel@de.ibm.com>

	* config/s390/s390.c (s390_emit_tls_call_insn): Remove assertion.
	Load GOT pointer for non-pic builds.
	(s390_load_got): Replace pic_offset_table_rtx with hardcoded r12.
	(s390_emit_call): Likewise.


Index: gcc/config/s390/s390.c
===================================================================
*** gcc/config/s390/s390.c.orig
--- gcc/config/s390/s390.c
*************** s390_emit_tls_call_insn (rtx result_reg,
*** 3604,3610 ****
  {
    rtx insn;
  
!   gcc_assert (flag_pic);
  
    if (!s390_tls_symbol)
      s390_tls_symbol = gen_rtx_SYMBOL_REF (Pmode, "__tls_get_offset");
--- 3604,3611 ----
  {
    rtx insn;
  
!   if (!flag_pic)
!     emit_insn (s390_load_got ());
  
    if (!s390_tls_symbol)
      s390_tls_symbol = gen_rtx_SYMBOL_REF (Pmode, "__tls_get_offset");
*************** s390_load_got (void)
*** 7859,7864 ****
--- 7860,7871 ----
  {
    rtx insns;
  
+   /* We cannot use pic_offset_table_rtx here since we use this
+      function also for non-pic if __tls_get_offset is called and in
+      that case PIC_OFFSET_TABLE_REGNUM as well as pic_offset_table_rtx
+      aren't usable.  */
+   rtx got_rtx = gen_rtx_REG (Pmode, 12);
+ 
    if (!got_symbol)
      {
        got_symbol = gen_rtx_SYMBOL_REF (Pmode, "_GLOBAL_OFFSET_TABLE_");
*************** s390_load_got (void)
*** 7869,7875 ****
  
    if (TARGET_CPU_ZARCH)
      {
!       emit_move_insn (pic_offset_table_rtx, got_symbol);
      }
    else
      {
--- 7876,7882 ----
  
    if (TARGET_CPU_ZARCH)
      {
!       emit_move_insn (got_rtx, got_symbol);
      }
    else
      {
*************** s390_load_got (void)
*** 7880,7892 ****
        offset = gen_rtx_CONST (Pmode, offset);
        offset = force_const_mem (Pmode, offset);
  
!       emit_move_insn (pic_offset_table_rtx, offset);
  
        offset = gen_rtx_UNSPEC (Pmode, gen_rtvec (1, XEXP (offset, 0)),
  			       UNSPEC_LTREL_BASE);
!       offset = gen_rtx_PLUS (Pmode, pic_offset_table_rtx, offset);
  
!       emit_move_insn (pic_offset_table_rtx, offset);
      }
  
    insns = get_insns ();
--- 7887,7899 ----
        offset = gen_rtx_CONST (Pmode, offset);
        offset = force_const_mem (Pmode, offset);
  
!       emit_move_insn (got_rtx, offset);
  
        offset = gen_rtx_UNSPEC (Pmode, gen_rtvec (1, XEXP (offset, 0)),
  			       UNSPEC_LTREL_BASE);
!       offset = gen_rtx_PLUS (Pmode, got_rtx, offset);
  
!       emit_move_insn (got_rtx, offset);
      }
  
    insns = get_insns ();
*************** s390_emit_call (rtx addr_location, rtx t
*** 9827,9834 ****
        /* s390_function_ok_for_sibcall should
  	 have denied sibcalls in this case.  */
        gcc_assert (retaddr_reg != NULL_RTX);
! 
!       use_reg (&CALL_INSN_FUNCTION_USAGE (insn), pic_offset_table_rtx);
      }
    return insn;
  }
--- 9834,9840 ----
        /* s390_function_ok_for_sibcall should
  	 have denied sibcalls in this case.  */
        gcc_assert (retaddr_reg != NULL_RTX);
!       use_reg (&CALL_INSN_FUNCTION_USAGE (insn), gen_rtx_REG (Pmode, 12));
      }
    return insn;
  }