Fix a bug in optimizing when the null constant has been DCE.
If it has been DCE, we should create a new one, instead of
using the old one.
Also move the first DCE to a place where it could actually
be useful.
bug:21870788
Change-Id: I28fc52ae481ef92cba45fc1b5abcf07c995f524c
diff --git a/test/501-null-constant-dce/info.txt b/test/501-null-constant-dce/info.txt
new file mode 100644
index 0000000..2c4a686
--- /dev/null
+++ b/test/501-null-constant-dce/info.txt
@@ -0,0 +1 @@
+Regression test for the optimizing compiler. See comment in smali file.