arm.md

这是一个linux 嵌入式系统中很重要的GCC编译器程序

		(match_operand:SI 1 "s_register_operand" "r")
		(match_operand:SI 2 "const_int_operand" "n")
		(match_operand:SI 3 "const_int_operand" "n"))
	       (const_int 0)))]
  "INTVAL (operands[3]) >= 0 && INTVAL (operands[3]) < 32
   && INTVAL (operands[2]) > 0 
   && INTVAL (operands[2]) + (INTVAL (operands[3]) & 1) <= 8
   && INTVAL (operands[2]) + INTVAL (operands[3]) <= 32"
  "*
  operands[2] = GEN_INT (((1 << INTVAL (operands[2])) - 1)
			 << INTVAL (operands[3]));
  output_asm_insn (\"ands\\t%0, %1, %2\", operands);
  return \"movne\\t%0, #1\";
"
[(set_attr "conds" "clob")
 (set_attr "length" "8")])

;;; ??? This pattern is bogus.  If operand3 has bits outside the range
;;; represented by the bitfield, then this will produce incorrect results.
;;; Somewhere, the value needs to be truncated.  On targets like the m68k,
;;; which have a real bitfield insert instruction, the truncation happens
;;; in the bitfield insert instruction itself.  Since arm does not have a
;;; bitfield insert instruction, we would have to emit code here to truncate
;;; the value before we insert.  This loses some of the advantage of having
;;; this insv pattern, so this pattern needs to be reevalutated.

(define_expand "insv"
  [(set (zero_extract:SI (match_operand:SI 0 "s_register_operand" "")
                         (match_operand:SI 1 "general_operand" "")
                         (match_operand:SI 2 "general_operand" ""))
        (match_operand:SI 3 "nonmemory_operand" ""))]
  ""
  "
{
  int start_bit = INTVAL (operands[2]);
  int width = INTVAL (operands[1]);
  HOST_WIDE_INT mask = (((HOST_WIDE_INT)1) << width) - 1;
  rtx target, subtarget;
  
  target = operands[0];
  /* Avoid using a subreg as a subtarget, and avoid writing a paradoxical 
     subreg as the final target.  */
  if (GET_CODE (target) == SUBREG)
    {
      subtarget = gen_reg_rtx (SImode);
      if (GET_MODE_SIZE (GET_MODE (SUBREG_REG (target)))
	  < GET_MODE_SIZE (SImode))
        target = SUBREG_REG (target);
    }
  else
    subtarget = target;    
    
  if (GET_CODE (operands[3]) == CONST_INT)
    {
      /* Since we are inserting a known constant, we may be able to
	 reduce the number of bits that we have to clear so that
	 the mask becomes simple.  */
      /* ??? This code does not check to see if the new mask is actually
	 simpler.  It may not be.  */
      rtx op1 = gen_reg_rtx (SImode);
      /* ??? Truncate operand3 to fit in the bitfield.  See comment before
	 start of this pattern.  */
      HOST_WIDE_INT op3_value = mask & INTVAL (operands[3]);
      HOST_WIDE_INT mask2 = ((mask & ~op3_value) << start_bit);

      emit_insn (gen_andsi3 (op1, operands[0], GEN_INT (~mask2)));
      emit_insn (gen_iorsi3 (subtarget, op1,
			     GEN_INT (op3_value << start_bit)));
    }
  else if (start_bit == 0
	   && ! (const_ok_for_arm (mask)
		 || const_ok_for_arm (~mask)))
    {
      /* A Trick, since we are setting the bottom bits in the word,
	 we can shift operand[3] up, operand[0] down, OR them together
	 and rotate the result back again.  This takes 3 insns, and
	 the third might be mergable into another op.  */
      /* The shift up copes with the possibility that operand[3] is
         wider than the bitfield.  */
      rtx op0 = gen_reg_rtx (SImode);
      rtx op1 = gen_reg_rtx (SImode);

      emit_insn (gen_ashlsi3 (op0, operands[3], GEN_INT (32 - width)));
      emit_insn (gen_iorsi3 (op1, gen_rtx_LSHIFTRT (SImode, operands[0],
							    operands[1]),
			     op0));
      emit_insn (gen_rotlsi3 (subtarget, op1, operands[1]));
    }
  else if ((width + start_bit == 32)
	   && ! (const_ok_for_arm (mask)
		 || const_ok_for_arm (~mask)))
    {
      /* Similar trick, but slightly less efficient.  */

      rtx op0 = gen_reg_rtx (SImode);
      rtx op1 = gen_reg_rtx (SImode);

      emit_insn (gen_ashlsi3 (op0, operands[3], GEN_INT (32 - width)));
      emit_insn (gen_ashlsi3 (op1, operands[0], operands[1]));
      emit_insn (gen_iorsi3 (subtarget,
			     gen_rtx_LSHIFTRT (SImode, op1, operands[1]),
			     op0));
    }
  else
    {
      rtx op0 = GEN_INT (mask);
      rtx op1 = gen_reg_rtx (SImode);
      rtx op2 = gen_reg_rtx (SImode);

      if (! (const_ok_for_arm (mask) || const_ok_for_arm (~mask)))
	{
	  rtx tmp = gen_reg_rtx (SImode);

	  emit_insn (gen_movsi (tmp, op0));
	  op0 = tmp;
	}

      /* Mask out any bits in operand[3] that are not needed.  */
      emit_insn (gen_andsi3 (op1, operands[3], op0));

      if (GET_CODE (op0) == CONST_INT
	  && (const_ok_for_arm (mask << start_bit)
	      || const_ok_for_arm (~ (mask << start_bit))))
	{
	  op0 = GEN_INT (~(mask << start_bit));
	  emit_insn (gen_andsi3 (op2, operands[0], op0));
	}
      else
	{
	  if (GET_CODE (op0) == CONST_INT)
	    {
	      rtx tmp = gen_reg_rtx (SImode);

	      emit_insn (gen_movsi (tmp, op0));
	      op0 = tmp;
	    }

	  if (start_bit != 0)
	    op0 = gen_rtx_ASHIFT (SImode, op0, operands[2]);
	    
	  emit_insn (gen_andsi_notsi_si (op2, operands[0], op0));
	}

      if (start_bit != 0)
	op1 = gen_rtx_ASHIFT (SImode, op1, operands[2]);

      emit_insn (gen_iorsi3 (subtarget, op1, op2));
    }

  if (subtarget != target)
    {
      /* If TARGET is still a SUBREG, then it must be wider than a word,
	 so we must be careful only to set the subword we were asked to. */
      if (GET_CODE (target) == SUBREG)
	emit_move_insn (target, subtarget);
      else
	emit_move_insn (target, gen_lowpart (GET_MODE (target), subtarget));
    }

  DONE;
}
")

;; constants for op 2 will never be given to these patterns.
(define_insn "*anddi_notdi_di"
  [(set (match_operand:DI 0 "s_register_operand" "=&r,&r")
	(and:DI (not:DI (match_operand:DI 2 "s_register_operand" "r,0"))
		(match_operand:DI 1 "s_register_operand" "0,r")))]
  ""
  "bic%?\\t%Q0, %Q1, %Q2\;bic%?\\t%R0, %R1, %R2"
[(set_attr "length" "8")])
  
(define_insn "*anddi_notzesidi_di"
  [(set (match_operand:DI 0 "s_register_operand" "=&r,&r")
	(and:DI (not:DI (zero_extend:DI
			 (match_operand:SI 2 "s_register_operand" "r,r")))
		(match_operand:DI 1 "s_register_operand" "0,?r")))]
  ""
  "@
   bic%?\\t%Q0, %Q1, %2
   bic%?\\t%Q0, %Q1, %2\;mov%?\\t%R0, %R1"
[(set_attr "length" "4,8")])
  
(define_insn "*anddi_notsesidi_di"
  [(set (match_operand:DI 0 "s_register_operand" "=&r,&r")
	(and:DI (not:DI (sign_extend:DI
			 (match_operand:SI 2 "s_register_operand" "r,r")))
		(match_operand:DI 1 "s_register_operand" "?r,0")))]
  ""
  "bic%?\\t%Q0, %Q1, %2\;bic%?\\t%R0, %R1, %2, asr #31"
[(set_attr "length" "8")])
  
(define_insn "andsi_notsi_si"
  [(set (match_operand:SI 0 "s_register_operand" "=r")
	(and:SI (not:SI (match_operand:SI 2 "s_register_operand" "r"))
		(match_operand:SI 1 "s_register_operand" "r")))]
  ""
  "bic%?\\t%0, %1, %2")

(define_insn "andsi_not_shiftsi_si"
  [(set (match_operand:SI 0 "s_register_operand" "=r")
	(and:SI (not:SI (match_operator:SI 4 "shift_operator"
			 [(match_operand:SI 2 "s_register_operand" "r")
			  (match_operand:SI 3 "arm_rhs_operand" "rM")]))
		(match_operand:SI 1 "s_register_operand" "r")))]
  ""
  "bic%?\\t%0, %1, %2%S4")

(define_insn "*andsi_notsi_si_compare0"
  [(set (reg:CC_NOOV 24)
	(compare:CC_NOOV
	 (and:SI (not:SI (match_operand:SI 2 "s_register_operand" "r"))
		 (match_operand:SI 1 "s_register_operand" "r"))
	 (const_int 0)))
   (set (match_operand:SI 0 "s_register_operand" "=r")
	(and:SI (not:SI (match_dup 2)) (match_dup 1)))]
  ""
  "bic%?s\\t%0, %1, %2"
[(set_attr "conds" "set")])

(define_insn "*andsi_notsi_si_compare0_scratch"
  [(set (reg:CC_NOOV 24)
	(compare:CC_NOOV
	 (and:SI (not:SI (match_operand:SI 2 "s_register_operand" "r"))
		 (match_operand:SI 1 "s_register_operand" "r"))
	 (const_int 0)))
   (clobber (match_scratch:SI 0 "=r"))]
  ""
  "bic%?s\\t%0, %1, %2"
[(set_attr "conds" "set")])

(define_insn "iordi3"
  [(set (match_operand:DI 0 "s_register_operand" "=&r")
	(ior:DI (match_operand:DI 1 "s_register_operand" "%0")
		(match_operand:DI 2 "s_register_operand" "r")))]
  ""
  "orr%?\\t%Q0, %Q1, %Q2\;orr%?\\t%R0, %R1, %R2"
[(set_attr "length" "8")])

(define_insn "*iordi_zesidi_di"
  [(set (match_operand:DI 0 "s_register_operand" "=&r,&r")
	(ior:DI (zero_extend:DI
		 (match_operand:SI 2 "s_register_operand" "r,r"))
		(match_operand:DI 1 "s_register_operand" "0,?r")))]
  ""
  "@
   orr%?\\t%Q0, %Q1, %2
   orr%?\\t%Q0, %Q1, %2\;mov%?\\t%R0, %R1"
[(set_attr "length" "4,8")])

(define_insn "*iordi_sesidi_di"
  [(set (match_operand:DI 0 "s_register_operand" "=&r,&r")
	(ior:DI (sign_extend:DI
		 (match_operand:SI 2 "s_register_operand" "r,r"))
		(match_operand:DI 1 "s_register_operand" "?r,0")))]
  ""
  "orr%?\\t%Q0, %Q1, %2\;orr%?\\t%R0, %R1, %2, asr #31"
[(set_attr "length" "8")])

(define_expand "iorsi3"
  [(set (match_operand:SI 0 "s_register_operand" "")
	(ior:SI (match_operand:SI 1 "s_register_operand" "")
		(match_operand:SI 2 "reg_or_int_operand" "")))]
  ""
  "
  if (GET_CODE (operands[2]) == CONST_INT)
    {
      arm_split_constant (IOR, SImode, INTVAL (operands[2]), operands[0],
			  operands[1],
			  (reload_in_progress || reload_completed
			   ? 0 : preserve_subexpressions_p ()));
      DONE;
    }
")

(define_insn "*iorsi3_insn"
  [(set (match_operand:SI 0 "s_register_operand" "=r,r")
	(ior:SI (match_operand:SI 1 "s_register_operand" "r,r")
		(match_operand:SI 2 "reg_or_int_operand" "rI,?n")))]
  ""
  "@
   orr%?\\t%0, %1, %2
   #"
[(set_attr "length" "4,16")])

(define_split
  [(set (match_operand:SI 0 "s_register_operand" "")
	(ior:SI (match_operand:SI 1 "s_register_operand" "")
		(match_operand:SI 2 "const_int_operand" "")))]
  "! const_ok_for_arm (INTVAL (operands[2]))"
  [(clobber (const_int 0))]
  "
  arm_split_constant (IOR, SImode, INTVAL (operands[2]), operands[0],
		      operands[1], 0);
  DONE;
")
  
(define_insn "*iorsi3_compare0"
  [(set (reg:CC_NOOV 24)
	(compare:CC_NOOV (ior:SI (match_operand:SI 1 "s_register_operand" "%r")
				 (match_operand:SI 2 "arm_rhs_operand" "rI"))
			 (const_int 0)))
   (set (match_operand:SI 0 "s_register_operand" "=r")
	(ior:SI (match_dup 1) (match_dup 2)))]
  ""
  "orr%?s\\t%0, %1, %2"
[(set_attr "conds" "set")])

(define_insn "*iorsi3_compare0_scratch"
  [(set (reg:CC_NOOV 24)
	(compare:CC_NOOV (ior:SI (match_operand:SI 1 "s_register_operand" "%r")
				 (match_operand:SI 2 "arm_rhs_operand" "rI"))
			 (const_int 0)))
   (clobber (match_scratch:SI 0 "=r"))]
  ""
  "orr%?s\\t%0, %1, %2"
[(set_attr "conds" "set")])

(define_insn "xordi3"
  [(set (match_operand:DI 0 "s_register_operand" "=&r,&r")
	(xor:DI (match_operand:DI 1 "s_register_operand" "%0,0")
		(match_operand:DI 2 "s_register_operand" "r,0")))]
  ""
  "eor%?\\t%Q0, %Q1, %Q2\;eor%?\\t%R0, %R1, %R2"
[(set_attr "length" "8")])

(define_insn "*xordi_zesidi_di"
  [(set (match_operand:DI 0 "s_register_operand" "=&r,&r")
	(xor:DI (zero_extend:DI
		 (match_operand:SI 2 "s_register_operand" "r,r"))
		(match_operand:DI 1 "s_register_operand" "0,?r")))]
  ""
  "@
   eor%?\\t%Q0, %Q1, %2
   eor%?\\t%Q0, %Q1, %2\;mov%?\\t%R0, %R1"
[(set_attr "length" "4,8")])

(define_insn "*xordi_sesidi_di"
  [(set (match_operand:DI 0 "s_register_operand" "=&r,&r")
	(xor:DI (sign_extend:DI
		 (match_operand:SI 2 "s_register_operand" "r,r"))
		(match_operand:DI 1 "s_register_operand" "?r,0")))]
  ""
  "eor%?\\t%Q0, %Q1, %2\;eor%?\\t%R0, %R1, %2, asr #31"
[(set_attr "length" "8")])

(define_insn "xorsi3"
  [(set (match_operand:SI 0 "s_register_operand" "=r")
	(xor:SI (match_operand:SI 1 "s_register_operand" "r")
		(match_operand:SI 2 "arm_rhs_operand" "rI")))]
  ""
  "eor%?\\t%0, %1, %2")

(define_insn "*xorsi3_compare0"
  [(set (reg:CC_NOOV 24)
	(compare:CC_NOOV (xor:SI (match_operand:SI 1 "s_register_operand" "r")
				 (match_operand:SI 2 "arm_rhs_operand" "rI"))
			 (const_int 0)))
   (set (match_operand:SI 0 "s_register_operand" "=r")
	(xor:SI (match_dup 1) (match_dup 2)))]
  ""
  "eor%?s\\t%0, %1, %2"
[(set_attr "conds" "set")])

(define_insn "*xorsi3_compare0_scratch"
  [(set (reg:CC_NOOV 24)
	(compare:CC_NOOV (xor:SI (match_operand:SI 0 "s_register_operand" "r")
				 (match_operand:SI 1 "arm_rhs_operand" "rI"))
			 (const_int 0)))]
  ""
  "teq%?\\t%0, %1"
[(set_attr "conds" "set")])

;; by splitting (IOR (AND (NOT A) (NOT B)) C) as D = AND (IOR A B) (NOT C), 
;; (NOT D) we can sometimes merge the final NOT into one of the following
;; insns

(define_split
  [(set (match_operand:SI 0 "s_register_operand" "=r")
	(ior:SI (and:SI (not:SI (match_operand:SI 1 "s_register_operand" "r"))
			(not:SI (match_operand:SI 2 "arm_rhs_operand" "rI")))
		(match_operand:SI 3 "arm_rhs_operand" "rI")))
   (clobber (match_operand:SI 4 "s_register_operand" "=r"))]
  ""
  [(set (match_dup 4) (and:SI (ior:SI (match_dup 1) (match_dup 2))
			      (not:SI (match_dup 3))))
   (set (match_dup 0) (not:SI (match_dup 4)))]
  ""
)

(define_insn "*andsi_iorsi3_notsi"
  [(set (match_operand:SI 0 "s_register_operand" "=&r,&r,&r")
	(and:SI (ior:SI (match_operand:SI 1 "s_register_operand" "r,r,0")
			(match_operand:SI 2 "arm_rhs_operand" "rI,0,rI"))
		(not:SI (match_operand:SI 3 "arm_rhs_operand" "rI,rI,rI"))))]
  ""
  "orr%?\\t%0, %1, %2\;bic%?\\t%0, %0, %3"
[(set_attr "length" "8")])