From: Segher Boessenkool Date: Wed, 13 May 2015 11:26:45 +0000 (+0200) Subject: combine.c (simplify_set): When generating a CC set... X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=313b2cc05048521c3825e6a866860d6825bb4864;p=gcc.git combine.c (simplify_set): When generating a CC set... * combine.c (simplify_set): When generating a CC set, if the source already is in the correct mode, do not wrap it in a compare. Simplify the rest of that code. From-SVN: r223146 --- diff --git a/gcc/ChangeLog b/gcc/ChangeLog index d9a4fe43173..2f8a0205754 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,9 @@ +2015-05-13 Segher Boessenkool + + * combine.c (simplify_set): When generating a CC set, if the + source already is in the correct mode, do not wrap it in a + compare. Simplify the rest of that code. + 2015-05-13 Richard Biener PR tree-optimization/66123 diff --git a/gcc/combine.c b/gcc/combine.c index 1c1a74fdaa6..5bb49cbc538 100644 --- a/gcc/combine.c +++ b/gcc/combine.c @@ -6705,20 +6705,16 @@ simplify_set (rtx x) if (other_changed) undobuf.other_insn = other_insn; - /* Otherwise, if we didn't previously have a COMPARE in the - correct mode, we need one. */ - if (GET_CODE (src) != COMPARE || GET_MODE (src) != compare_mode) - { - SUBST (SET_SRC (x), gen_rtx_COMPARE (compare_mode, op0, op1)); - src = SET_SRC (x); - } - else if (GET_MODE (op0) == compare_mode && op1 == const0_rtx) + /* Don't generate a compare of a CC with 0, just use that CC. */ + if (GET_MODE (op0) == compare_mode && op1 == const0_rtx) { SUBST (SET_SRC (x), op0); src = SET_SRC (x); } - /* Otherwise, update the COMPARE if needed. */ - else if (XEXP (src, 0) != op0 || XEXP (src, 1) != op1) + /* Otherwise, if we didn't previously have the same COMPARE we + want, create it from scratch. */ + else if (GET_CODE (src) != COMPARE || GET_MODE (src) != compare_mode + || XEXP (src, 0) != op0 || XEXP (src, 1) != op1) { SUBST (SET_SRC (x), gen_rtx_COMPARE (compare_mode, op0, op1)); src = SET_SRC (x);