aarch64: Fix store-exclusive in load-operate LSE helpers

	PR target/91834
	* config/aarch64/lse.S (LDNM): Ensure STXR output does not
	overlap the inputs.

From-SVN: r276133

libgcc/ChangeLog

+2019-09-25  Richard Henderson  <richard.henderson@linaro.org>
+
+	PR target/91834
+	* config/aarch64/lse.S (LDNM): Ensure STXR output does not
+	overlap the inputs.
+
 2019-09-25  Shaokun Zhang  <zhangshaokun@hisilicon.com>
 
 	* config/aarch64/sync-cache.c (__aarch64_sync_cache_range): Add support for

libgcc/config/aarch64/lse.S

@@ -227,8 +227,8 @@ STARTFN	NAME(LDNM)
 8:	mov		s(tmp0), s(0)
 0:	LDXR		s(0), [x1]
 	OP		s(tmp1), s(0), s(tmp0)
-	STXR		w(tmp1), s(tmp1), [x1]
-	cbnz		w(tmp1), 0b
+	STXR		w(tmp2), s(tmp1), [x1]
+	cbnz		w(tmp2), 0b
 	ret
 
 ENDFN	NAME(LDNM)