avr.c

linux下的gcc编译器

  if (cum->nregs && bytes <= cum->nregs)
    return gen_rtx (REG, mode, cum->regno - bytes);

  return NULL_RTX;
}

/* Update the summarizer variable CUM to advance past an argument
   in the argument list.  */
   
void
function_arg_advance (cum, mode, type, named)
     CUMULATIVE_ARGS *cum;      /* current arg information */
     enum machine_mode mode;    /* current arg mode */
     tree type;                 /* type of the argument or 0 if lib support */
     int named ATTRIBUTE_UNUSED; /* whether or not the argument was named */
{
  int bytes = avr_num_arg_regs (mode, type);

  cum->nregs -= bytes;
  cum->regno -= bytes;

  if (cum->nregs <= 0)
    {
      cum->nregs = 0;
      cum->regno = FIRST_CUM_REG;
    }
}

/***********************************************************************
  Functions for outputting various mov's for a various modes
************************************************************************/
const char *
output_movqi (insn, operands, l)
     rtx insn;
     rtx operands[];
     int *l;
{
  int dummy;
  rtx dest = operands[0];
  rtx src = operands[1];
  int *real_l = l;
  
  if (!l)
    l = &dummy;

  *l = 1;
  
  if (register_operand (dest, QImode))
    {
      if (register_operand (src, QImode)) /* mov r,r */
	{
	  if (test_hard_reg_class (STACK_REG, dest))
	    return AS2 (out,%0,%1);
	  else if (test_hard_reg_class (STACK_REG, src))
	    return AS2 (in,%0,%1);
	  
	  return AS2 (mov,%0,%1);
	}
      else if (CONSTANT_P (src))
	{
	  if (test_hard_reg_class (LD_REGS, dest)) /* ldi d,i */
	    return AS2 (ldi,%0,lo8(%1));
	  
	  if (GET_CODE (src) == CONST_INT)
	    {
	      if (src == const0_rtx) /* mov r,L */
		return AS1 (clr,%0);
	      else if (src == const1_rtx)
		{
		  if (reg_was_0 (insn, dest))
		    return AS1 (inc,%0 ; reg_was_0);

		  *l = 2;
		  return (AS1 (clr,%0) CR_TAB
			  AS1 (inc,%0));
		}
	      else if (src == constm1_rtx)
		{
		  /* Immediate constants -1 to any register */
		  if (reg_was_0 (insn, dest))
		    return AS1 (dec,%0 ; reg_was_0);

		  *l = 2;
		  return (AS1 (clr,%0) CR_TAB
			  AS1 (dec,%0));
		}
	      else
		{
		  int bit_nr = exact_log2 (INTVAL (src));

		  if (bit_nr >= 0)
		    {
		      if (reg_was_0 (insn, dest))
			{
			  *l = 2;
			  if (!real_l)
			    output_asm_insn ("set ; reg_was_0", operands);
			}
		      else
			{
			  *l = 3;
			  if (!real_l)
			    output_asm_insn ((AS1 (clr,%0) CR_TAB
					      "set"), operands);
			}
		      if (!real_l)
			avr_output_bld (operands, bit_nr);

		      return "";
		    }
		}
	    }
	  
	  /* Last resort, larger than loading from memory.  */
	  *l = 4;
	  return (AS2 (mov,__tmp_reg__,r31) CR_TAB
		  AS2 (ldi,r31,lo8(%1))     CR_TAB
		  AS2 (mov,%0,r31)          CR_TAB
		  AS2 (mov,r31,__tmp_reg__));
	}
      else if (GET_CODE (src) == MEM)
	return out_movqi_r_mr (insn, operands, real_l); /* mov r,m */
    }
  else if (GET_CODE (dest) == MEM)
    {
      const char *template;

      if (src == const0_rtx)
	operands[1] = zero_reg_rtx;

      template = out_movqi_mr_r (insn, operands, real_l);

      if (!real_l)
	output_asm_insn (template, operands);

      operands[1] = src;
    }
  return "";
}


const char *
output_movhi (insn, operands, l)
     rtx insn;
     rtx operands[];
     int *l;
{
  int dummy;
  rtx dest = operands[0];
  rtx src = operands[1];
  int *real_l = l;
  
  if (!l)
    l = &dummy;
  
  if (register_operand (dest, HImode))
    {
      if (register_operand (src, HImode)) /* mov r,r */
	{
	  if (test_hard_reg_class (STACK_REG, dest))
	    {
	      if (TARGET_TINY_STACK)
		{
		  *l = 1;
		  return AS2 (out,__SP_L__,%A1);
		}
	      else if (TARGET_NO_INTERRUPTS)
		{
		  *l = 2;
		  return (AS2 (out,__SP_H__,%B1) CR_TAB
			  AS2 (out,__SP_L__,%A1));
		}

	      *l = 5;
	      return (AS2 (in,__tmp_reg__,__SREG__)  CR_TAB
		      "cli"                          CR_TAB
		      AS2 (out,__SP_H__,%B1)         CR_TAB
		      AS2 (out,__SREG__,__tmp_reg__) CR_TAB
		      AS2 (out,__SP_L__,%A1));
	    }
	  else if (test_hard_reg_class (STACK_REG, src))
	    {
	      *l = 2;	
	      return (AS2 (in,%A0,__SP_L__) CR_TAB
		      AS2 (in,%B0,__SP_H__));
	    }

	  if (AVR_ENHANCED)
	    {
	      *l = 1;
	      return (AS2 (movw,%0,%1));
	    }

	  if (true_regnum (dest) > true_regnum (src))
	    {
	      *l = 2;
	      return (AS2 (mov,%B0,%B1) CR_TAB
		      AS2 (mov,%A0,%A1));
	    }
	  else
	    {
	      *l = 2;
	      return (AS2 (mov,%A0,%A1) CR_TAB
		      AS2 (mov,%B0,%B1));
	    }
	}
      else if (CONSTANT_P (src))
	{
	  if (test_hard_reg_class (LD_REGS, dest)) /* ldi d,i */
	    {
	      if (byte_immediate_operand (src, HImode)
		  && reg_was_0 (insn, dest))
		{
		  *l = 1;
		  return (AS2 (ldi,%A0,lo8(%1) ; reg_was_0));
		}

	      *l = 2;
	      return (AS2 (ldi,%A0,lo8(%1)) CR_TAB
		      AS2 (ldi,%B0,hi8(%1)));
	    }
	  
	  if (GET_CODE (src) == CONST_INT)
	    {
	      if (src == const0_rtx) /* mov r,L */
		{
		  *l = 2;
		  return (AS1 (clr,%A0) CR_TAB
			  AS1 (clr,%B0));
		}
	      else if (src == const1_rtx)
		{
		  if (reg_was_0 (insn, dest))
		    {
		      *l = 1;
		      return AS1 (inc,%0 ; reg_was_0);
		    }

		  *l = 3;
		  return (AS1 (clr,%A0) CR_TAB
			  AS1 (clr,%B0) CR_TAB
			  AS1 (inc,%A0));
		}
	      else if (src == constm1_rtx)
		{
		  /* Immediate constants -1 to any register */
		  if (reg_was_0 (insn, dest))
		    {
		      *l = 2;
		      return (AS1 (dec,%A0 ; reg_was_0) CR_TAB
			      AS1 (dec,%B0));
		    }

		  *l = 3;
		  return (AS1 (clr,%0)  CR_TAB
			  AS1 (dec,%A0) CR_TAB
			  AS2 (mov,%B0,%A0));
		}
	      else
		{
		  int bit_nr = exact_log2 (INTVAL (src));

		  if (bit_nr >= 0)
		    {
		      if (reg_was_0 (insn, dest))
			{
			  *l = 2;
			  if (!real_l)
			    output_asm_insn ("set ; reg_was_0", operands);
			}
		      else
			{
			  *l = 4;
			  if (!real_l)
			    output_asm_insn ((AS1 (clr,%A0) CR_TAB
					      AS1 (clr,%B0) CR_TAB
					      "set"), operands);
			}
		      if (!real_l)
			avr_output_bld (operands, bit_nr);

		      return "";
		    }
		}

	      if ((INTVAL (src) & 0xff) == 0)
		{
		  *l = 5;
		  return (AS2 (mov,__tmp_reg__,r31) CR_TAB
			  AS1 (clr,%A0)             CR_TAB
			  AS2 (ldi,r31,hi8(%1))     CR_TAB
			  AS2 (mov,%B0,r31)         CR_TAB
			  AS2 (mov,r31,__tmp_reg__));
		}
	      else if ((INTVAL (src) & 0xff00) == 0)
		{
		  *l = 5;
		  return (AS2 (mov,__tmp_reg__,r31) CR_TAB
			  AS2 (ldi,r31,lo8(%1))     CR_TAB
			  AS2 (mov,%A0,r31)         CR_TAB
			  AS1 (clr,%B0)             CR_TAB
			  AS2 (mov,r31,__tmp_reg__));
		}
	    }
	  
	  /* Last resort, equal to loading from memory.  */
	  *l = 6;
	  return (AS2 (mov,__tmp_reg__,r31) CR_TAB
		  AS2 (ldi,r31,lo8(%1))     CR_TAB
		  AS2 (mov,%A0,r31)         CR_TAB
		  AS2 (ldi,r31,hi8(%1))     CR_TAB
		  AS2 (mov,%B0,r31)         CR_TAB
		  AS2 (mov,r31,__tmp_reg__));
	}
      else if (GET_CODE (src) == MEM)
	return out_movhi_r_mr (insn, operands, real_l); /* mov r,m */
    }
  else if (GET_CODE (dest) == MEM)
    {
      const char *template;

      if (src == const0_rtx)
	operands[1] = zero_reg_rtx;

      template = out_movhi_mr_r (insn, operands, real_l);

      if (!real_l)
	output_asm_insn (template, operands);

      operands[1] = src;
      return "";
    }
  fatal_insn ("invalid insn:", insn);
  return "";
}

const char *
out_movqi_r_mr (insn, op, l)
     rtx insn;
     rtx op[];
     int *l; /* instruction length */
{
  rtx dest = op[0];
  rtx src = op[1];
  rtx x = XEXP (src, 0);
  int dummy;
  
  if (!l)
    l = &dummy;
  
  if (CONSTANT_ADDRESS_P (x))
    {
      if (avr_io_address_p (x, 1))
	{
	  *l = 1;
	  return AS2 (in,%0,%1-0x20);
	}
      *l = 2;
      return AS2 (lds,%0,%1);
    }
  /* memory access by reg+disp */
  else if (GET_CODE (x) == PLUS
      && REG_P (XEXP (x,0))
      && GET_CODE (XEXP (x,1)) == CONST_INT)
    {
      if ((INTVAL (XEXP (x,1)) - GET_MODE_SIZE (GET_MODE (src))) >= 63)
	{
	  int disp = INTVAL (XEXP (x,1));
	  if (REGNO (XEXP (x,0)) != REG_Y)
	    fatal_insn ("incorrect insn:",insn);

	  if (disp <= 63 + MAX_LD_OFFSET (GET_MODE (src)))
	    return *l = 3, (AS2 (adiw,r28,%o1-63) CR_TAB
			    AS2 (ldd,%0,Y+63)     CR_TAB
			    AS2 (sbiw,r28,%o1-63));

	  return *l = 5, (AS2 (subi,r28,lo8(-%o1)) CR_TAB
			  AS2 (sbci,r29,hi8(-%o1)) CR_TAB
			  AS2 (ld,%0,Y)            CR_TAB
			  AS2 (subi,r28,lo8(%o1))  CR_TAB
			  AS2 (sbci,r29,hi8(%o1)));
	}
      else if (REGNO (XEXP (x,0)) == REG_X)
	{
	  /* This is a paranoid case LEGITIMIZE_RELOAD_ADDRESS must exclude
	     it but I have this situation with extremal optimizing options.  */
	  if (reg_overlap_mentioned_p (dest, XEXP (x,0))
	      || reg_unused_after (insn, XEXP (x,0)))
	    return *l = 2, (AS2 (adiw,r26,%o1) CR_TAB
			    AS2 (ld,%0,X));

	  return *l = 3, (AS2 (adiw,r26,%o1) CR_TAB
			  AS2 (ld,%0,X)      CR_TAB
			  AS2 (sbiw,r26,%o1));
	}
      *l = 1;
      return AS2 (ldd,%0,%1);
    }
  *l = 1;
  return AS2 (ld,%0,%1);
}

const char *
out_movhi_r_mr (insn, op, l)
     rtx insn;
     rtx op[];
     int *l; /* instruction length */
{
  rtx dest = op[0];
  rtx src = op[1];
  rtx base = XEXP (src, 0);
  int reg_dest = true_regnum (dest);
  int reg_base = true_regnum (base);
  int tmp;

  if (!l)
    l = &tmp;

  if (reg_base > 0)
    {
      if (reg_dest == reg_base)         /* R = (R) */
	{
	  *l = 3;
	  return (AS2 (ld,__tmp_reg__,%1+) CR_TAB
		  AS2 (ld,%B0,%1) CR_TAB
		  AS2 (mov,%A0,__tmp_reg__));
	}
      else if (reg_base == REG_X)        /* (R26) */
        {
          if (reg_unused_after (insn, base))
	    {
	      *l = 2;
	      return (AS2 (ld,%A0,X+) CR_TAB
		      AS2 (ld,%B0,X));
	    }
	  *l  = 3;
	  return (AS2 (ld,%A0,X+) CR_TAB
		  AS2 (ld,%B0,X) CR_TAB
		  AS2 (sbiw,r26,1));
        }
      else                      /* (R)  */
	{
	  *l = 2;
	  return (AS2 (ld,%A0,%1)    CR_TAB
		  AS2 (ldd,%B0,%1+1));
	}
    }
  else if (GET_CODE (base) == PLUS) /* (R + i) */
    {
      int disp = INTVAL (XEXP (base, 1));
      int reg_base = true_regnum (XEXP (base, 0));
      
      if (disp > MAX_LD_OFFSET (GET_MODE (src)))
	{
	  if (REGNO (XEXP (base, 0)) != REG_Y)
	    fatal_insn ("incorrect insn:",insn);
	  
	  if (disp <= 63 + MAX_LD_OFFSET (GET_MODE (src)))
	    return *l = 4, (AS2 (adiw,r28,%o1-62) CR_TAB
			    AS2 (ldd,%A0,Y+62)    CR_TAB
			    AS2 (ldd,%B0,Y+63)    CR_TAB
			    AS2 (sbiw,r28,%o1-62));

	  return *l = 6, (AS2 (subi,r28,lo8(-%o1)) CR_TAB
			  AS2 (sbci,r29,hi8(-%o1)) CR_TAB
			  AS2 (ld,%A0,Y)           CR_TAB
			  AS2 (ldd,%B0,Y+1)        CR_TAB
			  AS2 (subi,r28,lo8(%o1))  CR_TAB
			  AS2 (sbci,r29,hi8(%o1)));
	}
      if (reg_base == REG_X)
	{
	  /* This is a paranoid case. LEGITIMIZE_RELOAD_ADDRESS must exclude
	     it but I have this situation with extremal
	     optimization options.  */
	  
	  *l = 4;
	  if (reg_base == reg_dest)
	    return (AS2 (adiw,r26,%o1)      CR_TAB
		    AS2 (ld,__tmp_reg__,X+) CR_TAB
		    AS2 (ld,%B0,X)          CR_TAB
		    AS2 (mov,%A0,__tmp_reg__));

	  return (AS2 (adiw,r26,%o1) CR_TAB
		  AS2 (ld,%A0,X+)    CR_TAB
		  AS2 (ld,%B0,X)     CR_TAB
		  AS2 (sbiw,r26,%o1+1));
	}

      if (reg_base == reg_dest)
	{
	  *l = 3;
	  return (AS2 (ldd,__tmp_reg__,%A1) CR_TAB
		  AS2 (ldd,%B0,%B1)         CR_TAB
		  AS2 (mov,%A0,__tmp_reg__));
	}
      
      *l = 2;
      return (AS2 (ldd,%A0,%A1) CR_TAB
	      AS2 (ldd,%B0,%B1));
    }
  else if (GET_CODE (base) == PRE_DEC) /* (--R) */
    {
      if (reg_overlap_mentioned_p (dest, XEXP (base, 0)))
	fatal_insn ("incorrect insn:", insn);

      *l = 2;
      return (AS2 (ld,%B0,%1) CR_TAB
	      AS2 (ld,%A0,%1));