From 7b57d1d3179b303355eee52b733acc7762a66e67 Mon Sep 17 00:00:00 2001
From: Richard Kenner <kenner@gcc.gnu.org>
Date: Sat, 3 Jun 1995 22:08:38 -0400
Subject: [PATCH] (attach_deaths): Don't add a REG_DEAD note if a REG_UNUSED
 note is already present.

From-SVN: r9871
---
 gcc/sched.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/gcc/sched.c b/gcc/sched.c
index 97332280f40..ccd8b563a7a 100644
--- a/gcc/sched.c
+++ b/gcc/sched.c
@@ -2864,7 +2864,12 @@ attach_deaths (x, insn, set_p)
 #endif
 		&& regno != STACK_POINTER_REGNUM)
 	      {
-		if (! all_needed && ! dead_or_set_p (insn, x))
+		/* ??? It is perhaps a dead_or_set_p bug that it does
+		   not check for REG_UNUSED notes itself.  This is necessary
+		   for the case where the SET_DEST is a subreg of regno, as
+		   dead_or_set_p handles subregs specially.  */
+		if (! all_needed && ! dead_or_set_p (insn, x)
+		    && ! find_regno_note (insn, REG_UNUSED, regno))
 		  {
 		    /* Check for the case where the register dying partially
 		       overlaps the register set by this insn.  */
-- 
2.30.2