i386.c

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  if (ix86_align_loops_string)
    {
      warning (0, "-malign-loops is obsolete, use -falign-loops");
      if (align_loops == 0)
	{
	  i = atoi (ix86_align_loops_string);
	  if (i < 0 || i > MAX_CODE_ALIGN)
	    error ("-malign-loops=%d is not between 0 and %d", i, MAX_CODE_ALIGN);
	  else
	    align_loops = 1 << i;
	}
    }

  if (ix86_align_jumps_string)
    {
      warning (0, "-malign-jumps is obsolete, use -falign-jumps");
      if (align_jumps == 0)
	{
	  i = atoi (ix86_align_jumps_string);
	  if (i < 0 || i > MAX_CODE_ALIGN)
	    error ("-malign-loops=%d is not between 0 and %d", i, MAX_CODE_ALIGN);
	  else
	    align_jumps = 1 << i;
	}
    }

  if (ix86_align_funcs_string)
    {
      warning (0, "-malign-functions is obsolete, use -falign-functions");
      if (align_functions == 0)
	{
	  i = atoi (ix86_align_funcs_string);
	  if (i < 0 || i > MAX_CODE_ALIGN)
	    error ("-malign-loops=%d is not between 0 and %d", i, MAX_CODE_ALIGN);
	  else
	    align_functions = 1 << i;
	}
    }

  /* Default align_* from the processor table.  */
  if (align_loops == 0)
    {
      align_loops = processor_target_table[ix86_tune].align_loop;
      align_loops_max_skip = processor_target_table[ix86_tune].align_loop_max_skip;
    }
  if (align_jumps == 0)
    {
      align_jumps = processor_target_table[ix86_tune].align_jump;
      align_jumps_max_skip = processor_target_table[ix86_tune].align_jump_max_skip;
    }
  if (align_functions == 0)
    {
      align_functions = processor_target_table[ix86_tune].align_func;
    }

  /* Validate -mpreferred-stack-boundary= value, or provide default.
     The default of 128 bits is for Pentium III's SSE __m128, but we
     don't want additional code to keep the stack aligned when
     optimizing for code size.  */
  ix86_preferred_stack_boundary = (optimize_size
				   ? TARGET_64BIT ? 128 : 32
				   : 128);
  if (ix86_preferred_stack_boundary_string)
    {
      i = atoi (ix86_preferred_stack_boundary_string);
      if (i < (TARGET_64BIT ? 4 : 2) || i > 12)
	error ("-mpreferred-stack-boundary=%d is not between %d and 12", i,
	       TARGET_64BIT ? 4 : 2);
      else
	ix86_preferred_stack_boundary = (1 << i) * BITS_PER_UNIT;
    }

  /* Validate -mbranch-cost= value, or provide default.  */
  ix86_branch_cost = processor_target_table[ix86_tune].cost->branch_cost;
  if (ix86_branch_cost_string)
    {
      i = atoi (ix86_branch_cost_string);
      if (i < 0 || i > 5)
	error ("-mbranch-cost=%d is not between 0 and 5", i);
      else
	ix86_branch_cost = i;
    }
  if (ix86_section_threshold_string)
    {
      i = atoi (ix86_section_threshold_string);
      if (i < 0)
	error ("-mlarge-data-threshold=%d is negative", i);
      else
	ix86_section_threshold = i;
    }

  if (ix86_tls_dialect_string)
    {
      if (strcmp (ix86_tls_dialect_string, "gnu") == 0)
	ix86_tls_dialect = TLS_DIALECT_GNU;
      else if (strcmp (ix86_tls_dialect_string, "sun") == 0)
	ix86_tls_dialect = TLS_DIALECT_SUN;
      else
	error ("bad value (%s) for -mtls-dialect= switch",
	       ix86_tls_dialect_string);
    }

  /* Keep nonleaf frame pointers.  */
  if (flag_omit_frame_pointer)
    target_flags &= ~MASK_OMIT_LEAF_FRAME_POINTER;
  else if (TARGET_OMIT_LEAF_FRAME_POINTER)
    flag_omit_frame_pointer = 1;

  /* If we're doing fast math, we don't care about comparison order
     wrt NaNs.  This lets us use a shorter comparison sequence.  */
  if (flag_unsafe_math_optimizations)
    target_flags &= ~MASK_IEEE_FP;

  /* If the architecture always has an FPU, turn off NO_FANCY_MATH_387,
     since the insns won't need emulation.  */
  if (x86_arch_always_fancy_math_387 & (1 << ix86_arch))
    target_flags &= ~MASK_NO_FANCY_MATH_387;

  /* Likewise, if the target doesn't have a 387, or we've specified
     software floating point, don't use 387 inline intrinsics.  */
  if (!TARGET_80387)
    target_flags |= MASK_NO_FANCY_MATH_387;

  /* Turn on SSE2 builtins for -msse3.  */
  if (TARGET_SSE3)
    target_flags |= MASK_SSE2;

  /* Turn on SSE builtins for -msse2.  */
  if (TARGET_SSE2)
    target_flags |= MASK_SSE;

  /* Turn on MMX builtins for -msse.  */
  if (TARGET_SSE)
    {
      target_flags |= MASK_MMX & ~target_flags_explicit;
      x86_prefetch_sse = true;
    }

  /* Turn on MMX builtins for 3Dnow.  */
  if (TARGET_3DNOW)
    target_flags |= MASK_MMX;

  if (TARGET_64BIT)
    {
      if (TARGET_ALIGN_DOUBLE)
	error ("-malign-double makes no sense in the 64bit mode");
      if (TARGET_RTD)
	error ("-mrtd calling convention not supported in the 64bit mode");

      /* Enable by default the SSE and MMX builtins.  Do allow the user to
	 explicitly disable any of these.  In particular, disabling SSE and
	 MMX for kernel code is extremely useful.  */
      target_flags
	|= ((MASK_SSE2 | MASK_SSE | MASK_MMX | MASK_128BIT_LONG_DOUBLE)
	    & ~target_flags_explicit);
     }
  else
    {
      /* i386 ABI does not specify red zone.  It still makes sense to use it
         when programmer takes care to stack from being destroyed.  */
      if (!(target_flags_explicit & MASK_NO_RED_ZONE))
        target_flags |= MASK_NO_RED_ZONE;
    }

  /* Accept -msseregparm only if at least SSE support is enabled.  */
  if (TARGET_SSEREGPARM
      && ! TARGET_SSE)
    error ("-msseregparm used without SSE enabled");

  ix86_fpmath = TARGET_FPMATH_DEFAULT;

  if (ix86_fpmath_string != 0)
    {
      if (! strcmp (ix86_fpmath_string, "387"))
	ix86_fpmath = FPMATH_387;
      else if (! strcmp (ix86_fpmath_string, "sse"))
	{
	  if (!TARGET_SSE)
	    {
	      warning (0, "SSE instruction set disabled, using 387 arithmetics");
	      ix86_fpmath = FPMATH_387;
	    }
	  else
	    ix86_fpmath = FPMATH_SSE;
	}
      else if (! strcmp (ix86_fpmath_string, "387,sse")
	       || ! strcmp (ix86_fpmath_string, "sse,387"))
	{
	  if (!TARGET_SSE)
	    {
	      warning (0, "SSE instruction set disabled, using 387 arithmetics");
	      ix86_fpmath = FPMATH_387;
	    }
	  else if (!TARGET_80387)
	    {
	      warning (0, "387 instruction set disabled, using SSE arithmetics");
	      ix86_fpmath = FPMATH_SSE;
	    }
	  else
	    ix86_fpmath = FPMATH_SSE | FPMATH_387;
	}
      else
	error ("bad value (%s) for -mfpmath= switch", ix86_fpmath_string);
    }

  /* If the i387 is disabled, then do not return values in it. */
  if (!TARGET_80387)
    target_flags &= ~MASK_FLOAT_RETURNS;

  if ((x86_accumulate_outgoing_args & TUNEMASK)
      && !(target_flags_explicit & MASK_ACCUMULATE_OUTGOING_ARGS)
      && !optimize_size)
    target_flags |= MASK_ACCUMULATE_OUTGOING_ARGS;

  /* ??? Unwind info is not correct around the CFG unless either a frame
     pointer is present or M_A_O_A is set.  Fixing this requires rewriting
     unwind info generation to be aware of the CFG and propagating states
     around edges.  */
  if ((flag_unwind_tables || flag_asynchronous_unwind_tables
       || flag_exceptions || flag_non_call_exceptions)
      && flag_omit_frame_pointer
      && !(target_flags & MASK_ACCUMULATE_OUTGOING_ARGS))
    {
      if (target_flags_explicit & MASK_ACCUMULATE_OUTGOING_ARGS)
	warning (0, "unwind tables currently require either a frame pointer "
		 "or -maccumulate-outgoing-args for correctness");
      target_flags |= MASK_ACCUMULATE_OUTGOING_ARGS;
    }

  /* Figure out what ASM_GENERATE_INTERNAL_LABEL builds as a prefix.  */
  {
    char *p;
    ASM_GENERATE_INTERNAL_LABEL (internal_label_prefix, "LX", 0);
    p = strchr (internal_label_prefix, 'X');
    internal_label_prefix_len = p - internal_label_prefix;
    *p = '\0';
  }

  /* When scheduling description is not available, disable scheduler pass
     so it won't slow down the compilation and make x87 code slower.  */
  if (!TARGET_SCHEDULE)
    flag_schedule_insns_after_reload = flag_schedule_insns = 0;
}

/* switch to the appropriate section for output of DECL.
   DECL is either a `VAR_DECL' node or a constant of some sort.
   RELOC indicates whether forming the initial value of DECL requires
   link-time relocations.  */

static void
x86_64_elf_select_section (tree decl, int reloc,
		         unsigned HOST_WIDE_INT align)
{
  if ((ix86_cmodel == CM_MEDIUM || ix86_cmodel == CM_MEDIUM_PIC)
      && ix86_in_large_data_p (decl))
    {
      const char *sname = NULL;
      unsigned int flags = SECTION_WRITE;
      switch (categorize_decl_for_section (decl, reloc, flag_pic))
	{
	case SECCAT_DATA:
	  sname = ".ldata";
	  break;
	case SECCAT_DATA_REL:
	  sname = ".ldata.rel";
	  break;
	case SECCAT_DATA_REL_LOCAL:
	  sname = ".ldata.rel.local";
	  break;
	case SECCAT_DATA_REL_RO:
	  sname = ".ldata.rel.ro";
	  break;
	case SECCAT_DATA_REL_RO_LOCAL:
	  sname = ".ldata.rel.ro.local";
	  break;
	case SECCAT_BSS:
	  sname = ".lbss";
	  flags |= SECTION_BSS;
	  break;
	case SECCAT_RODATA:
	case SECCAT_RODATA_MERGE_STR:
	case SECCAT_RODATA_MERGE_STR_INIT:
	case SECCAT_RODATA_MERGE_CONST:
	  sname = ".lrodata";
	  flags = 0;
	  break;
	case SECCAT_SRODATA:
	case SECCAT_SDATA:
	case SECCAT_SBSS:
	  gcc_unreachable ();
	case SECCAT_TEXT:
	case SECCAT_TDATA:
	case SECCAT_TBSS:
	  /* We don't split these for medium model.  Place them into
	     default sections and hope for best.  */
	  break;
	}
      if (sname)
	{
	  /* We might get called with string constants, but named_section
	     doesn't like them as they are not DECLs.  Also, we need to set
	     flags in that case.  */
	  if (!DECL_P (decl))
	    named_section_flags (sname, flags);
	  else
	    named_section (decl, sname, reloc);
	  return;
	}
    }
  default_elf_select_section (decl, reloc, align);
}

/* Build up a unique section name, expressed as a
   STRING_CST node, and assign it to DECL_SECTION_NAME (decl).
   RELOC indicates whether the initial value of EXP requires
   link-time relocations.  */

static void
x86_64_elf_unique_section (tree decl, int reloc)
{
  if ((ix86_cmodel == CM_MEDIUM || ix86_cmodel == CM_MEDIUM_PIC)
      && ix86_in_large_data_p (decl))
    {
      const char *prefix = NULL;
      /* We only need to use .gnu.linkonce if we don't have COMDAT groups.  */
      bool one_only = DECL_ONE_ONLY (decl) && !HAVE_COMDAT_GROUP;

      switch (categorize_decl_for_section (decl, reloc, flag_pic))
	{
	case SECCAT_DATA:
	case SECCAT_DATA_REL:
	case SECCAT_DATA_REL_LOCAL:
	case SECCAT_DATA_REL_RO:
	case SECCAT_DATA_REL_RO_LOCAL:
          prefix = one_only ? ".gnu.linkonce.ld." : ".ldata.";
	  break;
	case SECCAT_BSS:
          prefix = one_only ? ".gnu.linkonce.lb." : ".lbss.";
	  break;
	case SECCAT_RODATA:
	case SECCAT_RODATA_MERGE_STR:
	case SECCAT_RODATA_MERGE_STR_INIT:
	case SECCAT_RODATA_MERGE_CONST:
          prefix = one_only ? ".gnu.linkonce.lr." : ".lrodata.";
	  break;
	case SECCAT_SRODATA:
	case SECCAT_SDATA:
	case SECCAT_SBSS:
	  gcc_unreachable ();
	case SECCAT_TEXT:
	case SECCAT_TDATA:
	case SECCAT_TBSS:
	  /* We don't split these for medium model.  Place them into
	     default sections and hope for best.  */
	  break;
	}
      if (prefix)
	{
	  const char