diff --git a/gcc/expmed.c b/gcc/expmed.c index a57992e487e..f828e7f07a0 100644 --- a/gcc/expmed.c +++ b/gcc/expmed.c @@ -2560,8 +2560,9 @@ expand_divmod (rem_flag, code, mode, op0, op1, target, unsignedp) int op1_is_constant, op1_is_pow2; op1_is_constant = GET_CODE (op1) == CONST_INT; - op1_is_pow2 = (EXACT_POWER_OF_2_OR_ZERO_P (INTVAL (op1)) - || EXACT_POWER_OF_2_OR_ZERO_P (-INTVAL (op1))); + op1_is_pow2 = (op1_is_constant + && ((EXACT_POWER_OF_2_OR_ZERO_P (INTVAL (op1)) + || EXACT_POWER_OF_2_OR_ZERO_P (-INTVAL (op1))))); /* This is the structure of expand_divmod: @@ -3112,6 +3113,24 @@ expand_divmod (rem_flag, code, mode, op0, op1, target, unsignedp) case CEIL_MOD_EXPR: if (unsignedp) { + if (op1_is_constant && EXACT_POWER_OF_2_OR_ZERO_P (INTVAL (op1))) + { + rtx t1, t2, t3; + unsigned HOST_WIDE_INT d = INTVAL (op1); + t1 = expand_shift (RSHIFT_EXPR, compute_mode, op0, + build_int_2 (floor_log2 (d), 0), + NULL_RTX, 1); + t2 = expand_binop (compute_mode, and_optab, op0, + GEN_INT (d - 1), + NULL_RTX, 1, OPTAB_LIB_WIDEN); + t3 = gen_reg_rtx (compute_mode); + t3 = emit_store_flag (t3, NE, t2, const0_rtx, + compute_mode, 1, 1); + quotient = force_operand (gen_rtx (PLUS, compute_mode, + t1, t3), + tquotient); + break; + } /* Try using an instruction that produces both the quotient and remainder, using truncation. We can easily compensate the