[(set_attr "type" "cmp")])
;; If we are comparing a register for equality with a large constant,
-;; we can do this with an XOR followed by a compare. But we need a scratch
-;; register for the result of the XOR.
+;; we can do this with an XOR followed by a compare. But this is profitable
+;; only if the large constant is only used for the comparison (and in this
+;; case we already have a register to reuse as scratch).
-(define_split
- [(set (match_operand:CC 0 "cc_reg_operand" "")
- (compare:CC (match_operand:SI 1 "gpc_reg_operand" "")
- (match_operand:SI 2 "non_short_cint_operand" "")))
- (clobber (match_operand:SI 3 "gpc_reg_operand" ""))]
- "find_single_use (operands[0], insn, 0)
- && (GET_CODE (*find_single_use (operands[0], insn, 0)) == EQ
- || GET_CODE (*find_single_use (operands[0], insn, 0)) == NE)"
- [(set (match_dup 3) (xor:SI (match_dup 1) (match_dup 4)))
- (set (match_dup 0) (compare:CC (match_dup 3) (match_dup 5)))]
- "
-{
- /* Get the constant we are comparing against, C, and see what it looks like
- sign-extended to 16 bits. Then see what constant could be XOR'ed
- with C to get the sign-extended value. */
-
- HOST_WIDE_INT c = INTVAL (operands[2]);
+(define_peephole2
+ [(set (match_operand:GPR 0 "register_operand")
+ (match_operand:GPR 1 "logical_operand" ""))
+ (set (match_dup 0) (match_operator:GPR 3 "boolean_or_operator"
+ [(match_dup 0)
+ (match_operand:GPR 2 "logical_operand" "")]))
+ (set (match_operand:CC 4 "cc_reg_operand" "")
+ (compare:CC (match_operand:GPR 5 "gpc_reg_operand" "")
+ (match_dup 0)))
+ (set (pc)
+ (if_then_else (match_operator 6 "equality_operator"
+ [(match_dup 4) (const_int 0)])
+ (match_operand 7 "" "")
+ (match_operand 8 "" "")))]
+ "peep2_reg_dead_p (3, operands[0])"
+ [(set (match_dup 0) (xor:GPR (match_dup 5) (match_dup 9)))
+ (set (match_dup 4) (compare:CC (match_dup 0) (match_dup 10)))
+ (set (pc) (if_then_else (match_dup 6) (match_dup 7) (match_dup 8)))]
+
+{
+ /* Get the constant we are comparing against, and see what it looks like
+ when sign-extended from 16 to 32 bits. Then see what constant we could
+ XOR with SEXTC to get the sign-extended value. */
+ rtx cnst = simplify_const_binary_operation (GET_CODE (operands[3]),
+ GET_MODE (operands[3]),
+ operands[1], operands[2]);
+ HOST_WIDE_INT c = INTVAL (cnst);
HOST_WIDE_INT sextc = ((c & 0xffff) ^ 0x8000) - 0x8000;
HOST_WIDE_INT xorv = c ^ sextc;
- operands[4] = GEN_INT (xorv);
- operands[5] = GEN_INT (sextc);
-}")
+ operands[9] = GEN_INT (xorv);
+ operands[10] = GEN_INT (sextc);
+})
(define_insn "*cmpsi_internal2"
[(set (match_operand:CCUNS 0 "cc_reg_operand" "=y")