stormy16.c

Mac OS X 10.4.9 for x86 Source Code gcc 实现源代码

   saves of the caller saved registers.  In some cases, it might be
   necessary to emit a barrier instruction as the last insn to prevent
   such scheduling.  */

void
xstormy16_expand_epilogue (void)
{
  struct xstormy16_stack_layout layout;
  rtx mem_pop_rtx, insn;
  int regno;
  const int ifun = xstormy16_interrupt_function_p ();
  
  mem_pop_rtx = gen_rtx_PRE_DEC (Pmode, stack_pointer_rtx);
  mem_pop_rtx = gen_rtx_MEM (HImode, mem_pop_rtx);
  
  layout = xstormy16_compute_stack_layout ();

  /* Pop the stack for the locals.  */
  if (layout.locals_size)
    {
      if (frame_pointer_needed && layout.sp_minus_fp == layout.locals_size)
	emit_move_insn (stack_pointer_rtx, hard_frame_pointer_rtx);
      else
        {
	  insn = emit_addhi3_postreload (stack_pointer_rtx, stack_pointer_rtx,
					 GEN_INT (- layout.locals_size));
	  RTX_FRAME_RELATED_P (insn) = 1;
	}
    }

  /* Restore any call-saved registers.  */
  for (regno = FIRST_PSEUDO_REGISTER - 1; regno >= 0; regno--)
    if (REG_NEEDS_SAVE (regno, ifun))
      {
        rtx dwarf;

	insn = emit_move_insn (gen_rtx_REG (HImode, regno), mem_pop_rtx);
	RTX_FRAME_RELATED_P (insn) = 1;
	dwarf = gen_rtx_SET (Pmode, stack_pointer_rtx,
			     plus_constant (stack_pointer_rtx,
					    -GET_MODE_SIZE (Pmode)));
	REG_NOTES (insn) = gen_rtx_EXPR_LIST (REG_FRAME_RELATED_EXPR,
					      dwarf,
					      REG_NOTES (insn));
      }
  
  /* Pop the stack for the stdarg save area.  */
  if (layout.stdarg_save_size)
    {
      insn = emit_addhi3_postreload (stack_pointer_rtx, stack_pointer_rtx,
				     GEN_INT (- layout.stdarg_save_size));
      RTX_FRAME_RELATED_P (insn) = 1;
    }

  /* Return.  */
  if (ifun)
    emit_jump_insn (gen_return_internal_interrupt ());
  else
    emit_jump_insn (gen_return_internal ());
}

int
xstormy16_epilogue_uses (int regno)
{
  if (reload_completed && call_used_regs[regno])
    {
      const int ifun = xstormy16_interrupt_function_p ();
      return REG_NEEDS_SAVE (regno, ifun);
    }
  return 0;
}

void
xstormy16_function_profiler (void)
{
  sorry ("function_profiler support");
}


/* Return an updated summarizer variable CUM to advance past an
   argument in the argument list.  The values MODE, TYPE and NAMED
   describe that argument.  Once this is done, the variable CUM is
   suitable for analyzing the *following* argument with
   `FUNCTION_ARG', etc.

   This function need not do anything if the argument in question was
   passed on the stack.  The compiler knows how to track the amount of
   stack space used for arguments without any special help.  However,
   it makes life easier for xstormy16_build_va_list if it does update
   the word count.  */
CUMULATIVE_ARGS
xstormy16_function_arg_advance (CUMULATIVE_ARGS cum, enum machine_mode mode,
				tree type, int named ATTRIBUTE_UNUSED)
{
  /* If an argument would otherwise be passed partially in registers,
     and partially on the stack, the whole of it is passed on the
     stack.  */
  if (cum < NUM_ARGUMENT_REGISTERS
      && cum + XSTORMY16_WORD_SIZE (type, mode) > NUM_ARGUMENT_REGISTERS)
    cum = NUM_ARGUMENT_REGISTERS;
  
  cum += XSTORMY16_WORD_SIZE (type, mode);
  
  return cum;
}

rtx
xstormy16_function_arg (CUMULATIVE_ARGS cum, enum machine_mode mode,
			tree type, int named ATTRIBUTE_UNUSED)
{
  if (mode == VOIDmode)
    return const0_rtx;
  if (targetm.calls.must_pass_in_stack (mode, type)
      || cum + XSTORMY16_WORD_SIZE (type, mode) > NUM_ARGUMENT_REGISTERS)
    return 0;
  return gen_rtx_REG (mode, cum + 2);
}

/* Build the va_list type.

   For this chip, va_list is a record containing a counter and a pointer.
   The counter is of type 'int' and indicates how many bytes
   have been used to date.  The pointer indicates the stack position
   for arguments that have not been passed in registers.  
   To keep the layout nice, the pointer is first in the structure.  */

static tree
xstormy16_build_builtin_va_list (void)
{
  tree f_1, f_2, record, type_decl;

  record = (*lang_hooks.types.make_type) (RECORD_TYPE);
  type_decl = build_decl (TYPE_DECL, get_identifier ("__va_list_tag"), record);

  f_1 = build_decl (FIELD_DECL, get_identifier ("base"),
		      ptr_type_node);
  f_2 = build_decl (FIELD_DECL, get_identifier ("count"), 
		      unsigned_type_node);

  DECL_FIELD_CONTEXT (f_1) = record;
  DECL_FIELD_CONTEXT (f_2) = record;

  TREE_CHAIN (record) = type_decl;
  TYPE_NAME (record) = type_decl;
  TYPE_FIELDS (record) = f_1;
  TREE_CHAIN (f_1) = f_2;

  layout_type (record);

  return record;
}

/* Implement the stdarg/varargs va_start macro.  STDARG_P is nonzero if this
   is stdarg.h instead of varargs.h.  VALIST is the tree of the va_list
   variable to initialize.  NEXTARG is the machine independent notion of the
   'next' argument after the variable arguments.  */
void
xstormy16_expand_builtin_va_start (tree valist, rtx nextarg ATTRIBUTE_UNUSED)
{
  tree f_base, f_count;
  tree base, count;
  tree t;

  if (xstormy16_interrupt_function_p ())
    error ("cannot use va_start in interrupt function");
  
  f_base = TYPE_FIELDS (va_list_type_node);
  f_count = TREE_CHAIN (f_base);
  
  base = build (COMPONENT_REF, TREE_TYPE (f_base), valist, f_base, NULL_TREE);
  count = build (COMPONENT_REF, TREE_TYPE (f_count), valist, f_count,
		 NULL_TREE);

  t = make_tree (TREE_TYPE (base), virtual_incoming_args_rtx);
  t = build (PLUS_EXPR, TREE_TYPE (base), t, 
	     build_int_cst (NULL_TREE, INCOMING_FRAME_SP_OFFSET));
  t = build (MODIFY_EXPR, TREE_TYPE (base), base, t);
  TREE_SIDE_EFFECTS (t) = 1;
  expand_expr (t, const0_rtx, VOIDmode, EXPAND_NORMAL);

  t = build (MODIFY_EXPR, TREE_TYPE (count), count, 
	     build_int_cst (NULL_TREE,
			    current_function_args_info * UNITS_PER_WORD));
  TREE_SIDE_EFFECTS (t) = 1;
  expand_expr (t, const0_rtx, VOIDmode, EXPAND_NORMAL);
}

/* Implement the stdarg/varargs va_arg macro.  VALIST is the variable
   of type va_list as a tree, TYPE is the type passed to va_arg.
   Note:  This algorithm is documented in stormy-abi.  */
   
static tree
xstormy16_expand_builtin_va_arg (tree valist, tree type, tree *pre_p,
				 tree *post_p ATTRIBUTE_UNUSED)
{
  tree f_base, f_count;
  tree base, count;
  tree count_tmp, addr, t;
  tree lab_gotaddr, lab_fromstack;
  int size, size_of_reg_args, must_stack;
  tree size_tree;

  f_base = TYPE_FIELDS (va_list_type_node);
  f_count = TREE_CHAIN (f_base);
  
  base = build (COMPONENT_REF, TREE_TYPE (f_base), valist, f_base, NULL_TREE);
  count = build (COMPONENT_REF, TREE_TYPE (f_count), valist, f_count,
		 NULL_TREE);

  must_stack = targetm.calls.must_pass_in_stack (TYPE_MODE (type), type);
  size_tree = round_up (size_in_bytes (type), UNITS_PER_WORD);
  gimplify_expr (&size_tree, pre_p, NULL, is_gimple_val, fb_rvalue);
  
  size_of_reg_args = NUM_ARGUMENT_REGISTERS * UNITS_PER_WORD;

  count_tmp = get_initialized_tmp_var (count, pre_p, NULL);
  lab_gotaddr = create_artificial_label ();
  lab_fromstack = create_artificial_label ();
  addr = create_tmp_var (ptr_type_node, NULL);

  if (!must_stack)
    {
      tree r;

      t = fold_convert (TREE_TYPE (count), size_tree);
      t = build (PLUS_EXPR, TREE_TYPE (count), count_tmp, t);
      r = fold_convert (TREE_TYPE (count), size_int (size_of_reg_args));
      t = build (GT_EXPR, boolean_type_node, t, r);
      t = build (COND_EXPR, void_type_node, t,
		 build (GOTO_EXPR, void_type_node, lab_fromstack),
		 NULL);
      gimplify_and_add (t, pre_p);
  
      t = fold_convert (ptr_type_node, count_tmp);
      t = build (PLUS_EXPR, ptr_type_node, base, t);
      t = build (MODIFY_EXPR, void_type_node, addr, t);
      gimplify_and_add (t, pre_p);

      t = build (GOTO_EXPR, void_type_node, lab_gotaddr);
      gimplify_and_add (t, pre_p);

      t = build (LABEL_EXPR, void_type_node, lab_fromstack);
      gimplify_and_add (t, pre_p);
    }
  
  /* Arguments larger than a word might need to skip over some
     registers, since arguments are either passed entirely in
     registers or entirely on the stack.  */
  size = PUSH_ROUNDING (int_size_in_bytes (type));
  if (size > 2 || size < 0 || must_stack)
    {
      tree r, u;

      r = size_int (NUM_ARGUMENT_REGISTERS * UNITS_PER_WORD);
      u = build (MODIFY_EXPR, void_type_node, count_tmp, r);

      t = fold_convert (TREE_TYPE (count), r);
      t = build (GE_EXPR, boolean_type_node, count_tmp, t);
      t = build (COND_EXPR, void_type_node, t, NULL, u);
      gimplify_and_add (t, pre_p);
    }

  t = size_int (NUM_ARGUMENT_REGISTERS * UNITS_PER_WORD
		- INCOMING_FRAME_SP_OFFSET);
  t = fold_convert (TREE_TYPE (count), t);
  t = build (MINUS_EXPR, TREE_TYPE (count), count_tmp, t);
  t = build (PLUS_EXPR, TREE_TYPE (count), t,
	     fold_convert (TREE_TYPE (count), size_tree));
  t = fold_convert (TREE_TYPE (base), fold (t));
  t = build (MINUS_EXPR, TREE_TYPE (base), base, t);
  t = build (MODIFY_EXPR, void_type_node, addr, t);
  gimplify_and_add (t, pre_p);

  t = build (LABEL_EXPR, void_type_node, lab_gotaddr);
  gimplify_and_add (t, pre_p);

  t = fold_convert (TREE_TYPE (count), size_tree);
  t = build (PLUS_EXPR, TREE_TYPE (count), count_tmp, t);
  t = build (MODIFY_EXPR, TREE_TYPE (count), count, t);
  gimplify_and_add (t, pre_p);
  
  addr = fold_convert (build_pointer_type (type), addr);
  return build_fold_indirect_ref (addr);
}

/* Initialize the variable parts of a trampoline.  ADDR is an RTX for
   the address of the trampoline; FNADDR is an RTX for the address of
   the nested function; STATIC_CHAIN is an RTX for the static chain
   value that should be passed to the function when it is called.  */
void
xstormy16_initialize_trampoline (rtx addr, rtx fnaddr, rtx static_chain)
{
  rtx reg_addr = gen_reg_rtx (Pmode);
  rtx temp = gen_reg_rtx (HImode);
  rtx reg_fnaddr = gen_reg_rtx (HImode);
  rtx reg_addr_mem;

  reg_addr_mem = gen_rtx_MEM (HImode, reg_addr);
    
  emit_move_insn (reg_addr, addr);
  emit_move_insn (temp, GEN_INT (0x3130 | STATIC_CHAIN_REGNUM));
  emit_move_insn (reg_addr_mem, temp);
  emit_insn (gen_addhi3 (reg_addr, reg_addr, const2_rtx));
  emit_move_insn (temp, static_chain);
  emit_move_insn (reg_addr_mem, temp);
  emit_insn (gen_addhi3 (reg_addr, reg_addr, const2_rtx));
  emit_move_insn (reg_fnaddr, fnaddr);
  emit_move_insn (temp, reg_fnaddr);
  emit_insn (gen_andhi3 (temp, temp, GEN_INT (0xFF)));
  emit_insn (gen_iorhi3 (temp, temp, GEN_INT (0x0200)));
  emit_move_insn (reg_addr_mem, temp);
  emit_insn (gen_addhi3 (reg_addr, reg_addr, const2_rtx));
  emit_insn (gen_lshrhi3 (reg_fnaddr, reg_fnaddr, GEN_INT (8)));
  emit_move_insn (reg_addr_mem, reg_fnaddr);
}

/* Worker function for FUNCTION_VALUE.  */

rtx
xstormy16_function_value (tree valtype, tree func ATTRIBUTE_UNUSED)
{
  enum machine_mode mode;
  mode = TYPE_MODE (valtype);
  PROMOTE_MODE (mode, 0, valtype);
  return gen_rtx_REG (mode, RETURN_VALUE_REGNUM);
}

/* A C compound statement that outputs the assembler code for a thunk function,
   used to implement C++ virtual function calls with multiple inheritance.  The
   thunk acts as a wrapper around a virtual function, adjusting the implicit
   object parameter before handing control off to the real function.

   First, emit code to add the integer DELTA to the location that contains the
   incoming first argument.  Assume that this argument contains a pointer, and
   is the one used to pass the `this' pointer in C++.  This is the incoming
   argument *before* the function prologue, e.g. `%o0' on a sparc.  The
   addition must preserve the values of all other incoming arguments.

   After the addition, emit code to jump to FUNCTION, which is a
   `FUNCTION_DECL'.  This is a direct pure jump, not a call, and does not touch
   the return address.  Hence returning from FUNCTION will return to whoever
   called the current `thunk'.

   The effect must be as if @var{function} had been called directly
   with the adjusted first argument.  This macro is responsible for
   emitting all of the code for a thunk function;
   TARGET_ASM_FUNCTION_PROLOGUE and TARGET_ASM_FUNCTION_EPILOGUE are
   not invoked.

   The THUNK_FNDECL is redundant.  (DELTA and FUNCTION have already been
   extracted from it.)  It might possibly be useful on some targets, but
   probably not.  */

static void
xstormy16_asm_output_mi_thunk (FILE *file,
			       tree thunk_fndecl ATTRIBUTE_UNUSED,
			       HOST_WIDE_INT delta,
			       HOST_WIDE_INT vcall_offset ATTRIBUTE_UNUSED,
			       tree function)
{
  int regnum = FIRST_ARGUMENT_REGISTER;
  
  /* There might be a hidden first argument for a returned structure.  */
  if (aggregate_value_p (TREE_TYPE (TREE_TYPE (function)), function))
    regnum += 1;
  
  fprintf (file, "\tadd %s,#0x%x\n", reg_names[regnum], (int) delta & 0xFFFF);
  fputs ("\tjmpf ", file);
  assemble_name (file, XSTR (XEXP (DECL_RTL (function), 0), 0));
  putc ('\n', file);
}

/* The purpose of this function is to override the default behavior of
   BSS objects.  Normally, they go into .bss or .sbss via ".common"
   directives, but we need to override that and put them in
   .bss_below100.  We can't just use a section override (like we do
   for .data_below100), because that makes them initialized rather
   than uninitialized.  */
void
xstormy16_asm_output_aligned_common (FILE *stream,
				     tree decl ATTRIBUTE_UNUSED,
				     const char *name,
				     int size,
				     int align,
				     int global)
{
  if (name[0] == '@' && name[2] == '.')
    {
      const char *op = 0;
      switch (name[1])
	{
	case 'b':
	  bss100_section();
	  op = "space";
	  break;
	}
      if (op)
	{
	  const char *name2;
	  int p2align = 0;

	  while (align > 8)
	    {
	      align /= 2;
	      p2align ++;
	    }
	  name2 = xstormy16_strip_name_encoding (name);
	  if (global)
	    fprintf (stream, "\t.globl\t%s\n", name2);
	  if (p2align)
	    fprintf (stream, "\t.p2align %d\n", p2align);
	  fprintf (stream, "\t.type\t%s, @object\n", name2);
	  fprintf (stream, "\t.size\t%s, %d\n", name2, size);
	  fprintf (stream, "%s:\n\t.%s\t%d\n", name2, op, size);
	  return;
	}
    }

  if (!global)
    {
      fprintf (stream, "\t.local\t");
      assemble_name (stream, name);
      fprintf (stream, "\n");
    }
  fprintf (stream, "\t.comm\t");
  assemble_name (stream, name);
  fprintf (stream, ",%u,%u\n", size, align / BITS_PER_UNIT);
}

/* Mark symbols with the "below100" attribute so that we can use the
   special addressing modes for them.  */

static void
xstormy16_encode_section_info (tree decl,
			       rtx r,
			       int first ATTRIBUTE_UNUSED)
{
  if (TREE_CODE (decl) == VAR_DECL