diff options
Diffstat (limited to 'gcc/combine.c')
| -rw-r--r-- | gcc/combine.c | 41 |
1 files changed, 0 insertions, 41 deletions
diff --git a/gcc/combine.c b/gcc/combine.c index 313a3d90d23..89866e0fa3d 100644 --- a/gcc/combine.c +++ b/gcc/combine.c @@ -3768,47 +3768,6 @@ combine_simplify_rtx (rtx x, enum machine_mode op0_mode, int in_dest) SUBST (XEXP (x, 1), temp); } - /* If this is a PLUS, MINUS, or MULT, and the first operand is the - sign extension of a PLUS with a constant, reverse the order of the sign - extension and the addition. Note that this not the same as the original - code, but overflow is undefined for signed values. Also note that the - PLUS will have been partially moved "inside" the sign-extension, so that - the first operand of X will really look like: - (ashiftrt (plus (ashift A C4) C5) C4). - We convert this to - (plus (ashiftrt (ashift A C4) C2) C4) - and replace the first operand of X with that expression. Later parts - of this function may simplify the expression further. - - For example, if we start with (mult (sign_extend (plus A C1)) C2), - we swap the SIGN_EXTEND and PLUS. Later code will apply the - distributive law to produce (plus (mult (sign_extend X) C1) C3). - - We do this to simplify address expressions. */ - - if ((code == PLUS || code == MINUS || code == MULT) - && GET_CODE (XEXP (x, 0)) == ASHIFTRT - && GET_CODE (XEXP (XEXP (x, 0), 0)) == PLUS - && GET_CODE (XEXP (XEXP (XEXP (x, 0), 0), 0)) == ASHIFT - && GET_CODE (XEXP (XEXP (XEXP (XEXP (x, 0), 0), 0), 1)) == CONST_INT - && GET_CODE (XEXP (XEXP (x, 0), 1)) == CONST_INT - && XEXP (XEXP (XEXP (XEXP (x, 0), 0), 0), 1) == XEXP (XEXP (x, 0), 1) - && GET_CODE (XEXP (XEXP (XEXP (x, 0), 0), 1)) == CONST_INT - && (temp = simplify_binary_operation (ASHIFTRT, mode, - XEXP (XEXP (XEXP (x, 0), 0), 1), - XEXP (XEXP (x, 0), 1))) != 0) - { - rtx new - = simplify_shift_const (NULL_RTX, ASHIFT, mode, - XEXP (XEXP (XEXP (XEXP (x, 0), 0), 0), 0), - INTVAL (XEXP (XEXP (x, 0), 1))); - - new = simplify_shift_const (NULL_RTX, ASHIFTRT, mode, new, - INTVAL (XEXP (XEXP (x, 0), 1))); - - SUBST (XEXP (x, 0), simplify_gen_binary (PLUS, mode, new, temp)); - } - /* If this is a simple operation applied to an IF_THEN_ELSE, try applying it to the arms of the IF_THEN_ELSE. This often simplifies things. Check for cases where both arms are testing the same |