diff --git a/gcc/combine.c b/gcc/combine.c index 2af4949e054f..5d21de343617 100644 --- a/gcc/combine.c +++ b/gcc/combine.c @@ -4652,6 +4652,19 @@ make_compound_operation (x, in_code) code == LSHIFTRT, 0, in_code == COMPARE); } + /* Similarly for (ashiftrt (neg (ashift FOO C1)) C2). */ + if (GET_CODE (XEXP (x, 1)) == CONST_INT + && GET_CODE (XEXP (x, 0)) == NEG + && GET_CODE (XEXP (XEXP (x, 0), 0)) == ASHIFT + && GET_CODE (XEXP (XEXP (XEXP (x, 0), 0), 1)) == CONST_INT + && INTVAL (XEXP (x, 1)) >= INTVAL (XEXP (XEXP (XEXP (x, 0), 0), 1))) + new = make_extraction (mode, + gen_unary (GET_CODE (XEXP (x, 0)), mode, + XEXP (XEXP (XEXP (x, 0), 0), 0)), + (INTVAL (XEXP (x, 1)) + - INTVAL (XEXP (XEXP (XEXP (x, 0), 0), 1))), + NULL_RTX, mode_width - INTVAL (XEXP (x, 1)), + code == LSHIFTRT, 0, in_code == COMPARE); break; }