re PR target/84209 ([avr] Don't split SP in split2)

	PR target/84209
	* config/avr/avr.h (GENERAL_REGNO_P, GENERAL_REG_P): New macros.
	* config/avr/avr.md: Only post-reload split REG-REG moves if
	either register is REGERAL_REG_P.

From-SVN: r257440

gcc/ChangeLog

+2018-02-07  Georg-Johann Lay  <avr@gjlay.de>
+
+	PR target/84209
+	* config/avr/avr.h (GENERAL_REGNO_P, GENERAL_REG_P): New macros.
+	* config/avr/avr.md: Only post-reload split REG-REG moves if
+	either register is REGERAL_REG_P.
+
 2018-02-07  Jakub Jelinek  <jakub@redhat.com>
 
 	PR tree-optimization/84235

gcc/config/avr/avr.h

@@ -153,6 +153,9 @@ FIXME: DRIVER_SELF_SPECS has changed.
 
 #define FIRST_PSEUDO_REGISTER 36
 
+#define GENERAL_REGNO_P(N)	IN_RANGE (N, 2, 31)
+#define GENERAL_REG_P(X)	(REG_P (X) && GENERAL_REGNO_P (REGNO (X)))
+
 #define FIXED_REGISTERS {\
   1,1,/* r0 r1 */\
   0,0,/* r2 r3 */\

gcc/config/avr/avr.md

@@ -3368,6 +3368,8 @@
         (match_operand:HI 1 "reg_or_0_operand"))]
   "optimize
    && reload_completed
+   && GENERAL_REG_P (operands[0])
+   && (operands[1] == const0_rtx || GENERAL_REG_P (operands[1]))
    && (!AVR_HAVE_MOVW
        || const0_rtx == operands[1])"
   [(set (match_dup 2) (match_dup 3))