From 21e16bd6bb7a838a70cad9f4f4c3f0fbdf824052 Mon Sep 17 00:00:00 2001 From: Richard Henderson Date: Tue, 8 Jan 2002 17:07:13 -0800 Subject: [PATCH] * regrename.c (copy_value): Ignore overlapping copies. From-SVN: r48669 --- gcc/ChangeLog | 4 ++++ gcc/regrename.c | 8 ++++++++ 2 files changed, 12 insertions(+) diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 72e514420a1..426d2db160c 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,7 @@ +2002-01-08 Richard Henderson + + * regrename.c (copy_value): Ignore overlapping copies. + 2002-01-08 Richard Henderson * config/alpha/alpha.c (alpha_split_conditional_move): Call copy_rtx diff --git a/gcc/regrename.c b/gcc/regrename.c index 45f5b8552ef..0079dc1e316 100644 --- a/gcc/regrename.c +++ b/gcc/regrename.c @@ -1214,6 +1214,7 @@ copy_value (dest, src, vd) { unsigned int dr = REGNO (dest); unsigned int sr = REGNO (src); + unsigned int dn, sn; unsigned int i; /* ??? At present, it's possible to see noop sets. It'd be nice if @@ -1230,6 +1231,13 @@ copy_value (dest, src, vd) if (frame_pointer_needed && dr == HARD_FRAME_POINTER_REGNUM) return; + /* If SRC and DEST overlap, don't record anything. */ + dn = HARD_REGNO_NREGS (dr, GET_MODE (dest)); + sn = HARD_REGNO_NREGS (sr, GET_MODE (dest)); + if ((dr > sr && dr < sr + sn) + || (sr > dr && sr < dr + dn)) + return; + /* If SRC had no assigned mode (i.e. we didn't know it was live) assign it now and assume the value came from an input argument or somesuch. */ -- 2.30.2