diff options
Diffstat (limited to 'gcc/combine.c')
| -rw-r--r-- | gcc/combine.c | 25 |
1 files changed, 3 insertions, 22 deletions
diff --git a/gcc/combine.c b/gcc/combine.c index d702d31..90a02cf 100644 --- a/gcc/combine.c +++ b/gcc/combine.c @@ -8029,28 +8029,9 @@ simplify_comparison (code, pop0, pop1) continue; } - /* If we have NEG of something that is the result of a - SIGN_EXTEND, SIGN_EXTRACT, or ASHIFTRT, we know that the - two high-order bits must be the same and hence that - "(-a) < 0" is equivalent to "a > 0". Otherwise, we can't - do this. */ - if (GET_CODE (XEXP (op0, 0)) == SIGN_EXTEND - || (GET_CODE (XEXP (op0, 0)) == SIGN_EXTRACT - && GET_CODE (XEXP (XEXP (op0, 0), 1)) == CONST_INT - && (INTVAL (XEXP (XEXP (op0, 0), 1)) - < GET_MODE_BITSIZE (GET_MODE (XEXP (XEXP (op0, 0), 0))))) - || (GET_CODE (XEXP (op0, 0)) == ASHIFTRT - && GET_CODE (XEXP (XEXP (op0, 0), 1)) == CONST_INT - && XEXP (XEXP (op0, 0), 1) != const0_rtx) - || ((tem = get_last_value (XEXP (op0, 0))) != 0 - && (GET_CODE (tem) == SIGN_EXTEND - || (GET_CODE (tem) == SIGN_EXTRACT - && GET_CODE (XEXP (tem, 1)) == CONST_INT - && (INTVAL (XEXP (tem, 1)) - < GET_MODE_BITSIZE (GET_MODE (XEXP (tem, 0))))) - || (GET_CODE (tem) == ASHIFTRT - && GET_CODE (XEXP (tem, 1)) == CONST_INT - && XEXP (tem, 1) != const0_rtx)))) + /* If we have NEG of something whose two high-order bits are the + same, we know that "(-a) < 0" is equivalent to "a > 0". */ + if (num_sign_bit_copies (op0, mode) >= 2) { op0 = XEXP (op0, 0); code = swap_condition (code); |