Add support for passing '-target armv8' through the Driver.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@184970 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Driver/ToolChain.cpp b/lib/Driver/ToolChain.cpp
index 5bc41f9..8676f7f 100644
--- a/lib/Driver/ToolChain.cpp
+++ b/lib/Driver/ToolChain.cpp
@@ -195,6 +195,7 @@
     .Cases("armv7r", "armv7-r", "cortex-r4")
     .Cases("armv7m", "armv7-m", "cortex-m3")
     .Cases("armv7em", "armv7e-m", "cortex-m4")
+    .Cases("armv8", "armv8a", "armv8-a", "cortex-a53")
     .Case("ep9312", "ep9312")
     .Case("iwmmxt", "iwmmxt")
     .Case("xscale", "xscale")
@@ -230,6 +231,7 @@
     .Case("cortex-m4", "v7em")
     .Case("cortex-a9-mp", "v7f")
     .Case("swift", "v7s")
+    .Case("cortex-a53", "v8")
     .Default("");
 }