From 0f2f71b552e7c1136401c3b7c7d8a28d92aed1bc Mon Sep 17 00:00:00 2001 From: Roger Sayle Date: Fri, 3 Mar 2006 05:55:02 +0000 Subject: [PATCH] simplify-rtx.c (simplify_unary_operation): When simplifying (neg (lt X 0)) into (ashiftrt X C) or (lshiftrt X C)... * simplify-rtx.c (simplify_unary_operation): When simplifying (neg (lt X 0)) into (ashiftrt X C) or (lshiftrt X C), make sure that we perform the right shift in the appropriate mode, and then extend or truncate the result to requested mode. From-SVN: r111671 --- gcc/ChangeLog | 10 +++++++++- gcc/simplify-rtx.c | 24 ++++++++++++++++++++---- 2 files changed, 29 insertions(+), 5 deletions(-) diff --git a/gcc/ChangeLog b/gcc/ChangeLog index a2508b6..7b330e5 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,10 @@ +2006-03-02 Roger Sayle + + * simplify-rtx.c (simplify_unary_operation): When simplifying + (neg (lt X 0)) into (ashiftrt X C) or (lshiftrt X C), make sure + that we perform the right shift in the appropriate mode, and + then extend or truncate the result to requested mode. + 2006-03-03 Zdenek Dvorak * gengtype.c (main): Handle double_int type. @@ -16,7 +23,8 @@ 2006-03-02 Zdenek Dvorak - * tree-vrp.c (remove_range_assertions): Do not update statements unnecessarily. + * tree-vrp.c (remove_range_assertions): Do not update statements + unnecessarily. 2006-03-02 Zdenek Dvorak diff --git a/gcc/simplify-rtx.c b/gcc/simplify-rtx.c index aded68e..754464d 100644 --- a/gcc/simplify-rtx.c +++ b/gcc/simplify-rtx.c @@ -590,12 +590,28 @@ simplify_unary_operation_1 (enum rtx_code code, enum machine_mode mode, rtx op) if (GET_CODE (op) == LT && XEXP (op, 1) == const0_rtx) { + enum machine_mode inner = GET_MODE (XEXP (op, 0)); + int isize = GET_MODE_BITSIZE (inner); if (STORE_FLAG_VALUE == 1) - return simplify_gen_binary (ASHIFTRT, mode, XEXP (op, 0), - GEN_INT (GET_MODE_BITSIZE (mode) - 1)); + { + temp = simplify_gen_binary (ASHIFTRT, inner, XEXP (op, 0), + GEN_INT (isize - 1)); + if (mode == inner) + return temp; + if (GET_MODE_BITSIZE (mode) > isize) + return simplify_gen_unary (SIGN_EXTEND, mode, temp, inner); + return simplify_gen_unary (TRUNCATE, mode, temp, inner); + } else if (STORE_FLAG_VALUE == -1) - return simplify_gen_binary (LSHIFTRT, mode, XEXP (op, 0), - GEN_INT (GET_MODE_BITSIZE (mode) - 1)); + { + temp = simplify_gen_binary (LSHIFTRT, inner, XEXP (op, 0), + GEN_INT (isize - 1)); + if (mode == inner) + return temp; + if (GET_MODE_BITSIZE (mode) > isize) + return simplify_gen_unary (ZERO_EXTEND, mode, temp, inner); + return simplify_gen_unary (TRUNCATE, mode, temp, inner); + } } break; -- 2.7.4