+ /* For constants M and N, if M == (1LL << cst) - 1 && (N & M) == M,
+ ((A & N) + B) & M -> (A + B) & M
+ Similarly if (N & M) == 0,
+ ((A | N) + B) & M -> (A + B) & M
+ and for - instead of + and/or ^ instead of |. */
+ if (GET_CODE (trueop1) == CONST_INT
+ && GET_MODE_BITSIZE (mode) <= HOST_BITS_PER_WIDE_INT
+ && ~INTVAL (trueop1)
+ && (INTVAL (trueop1) & (INTVAL (trueop1) + 1)) == 0
+ && (GET_CODE (op0) == PLUS || GET_CODE (op0) == MINUS))
+ {
+ rtx pmop[2];
+ int which;
+
+ pmop[0] = XEXP (op0, 0);
+ pmop[1] = XEXP (op0, 1);
+
+ for (which = 0; which < 2; which++)
+ {
+ tem = pmop[which];
+ switch (GET_CODE (tem))
+ {
+ case AND:
+ if (GET_CODE (XEXP (tem, 1)) == CONST_INT
+ && (INTVAL (XEXP (tem, 1)) & INTVAL (trueop1))
+ == INTVAL (trueop1))
+ pmop[which] = XEXP (tem, 0);
+ break;
+ case IOR:
+ case XOR:
+ if (GET_CODE (XEXP (tem, 1)) == CONST_INT
+ && (INTVAL (XEXP (tem, 1)) & INTVAL (trueop1)) == 0)
+ pmop[which] = XEXP (tem, 0);
+ break;
+ default:
+ break;
+ }
+ }
+
+ if (pmop[0] != XEXP (op0, 0) || pmop[1] != XEXP (op0, 1))
+ {
+ tem = simplify_gen_binary (GET_CODE (op0), mode,
+ pmop[0], pmop[1]);
+ return simplify_gen_binary (code, mode, tem, op1);
+ }
+ }