Implement a SIMD spilling slot.

Rationale:
The last ART vectorizer break-out CL    \O/
This ensures spilling on x86 and x86_4 is correct.
Also, it paves the way to wider SIMD on ARM and MIPS.

Test: test-art-host
Bug: 34083438

Change-Id: I5b27d18c2045f3ab70b64c335423b3ff2a507ac2
diff --git a/compiler/optimizing/graph_visualizer.cc b/compiler/optimizing/graph_visualizer.cc
index 2bf5c53..0dfae11 100644
--- a/compiler/optimizing/graph_visualizer.cc
+++ b/compiler/optimizing/graph_visualizer.cc
@@ -322,9 +322,11 @@
       codegen_.DumpCoreRegister(stream, location.high());
     } else if (location.IsUnallocated()) {
       stream << "unallocated";
-    } else {
-      DCHECK(location.IsDoubleStackSlot());
+    } else if (location.IsDoubleStackSlot()) {
       stream << "2x" << location.GetStackIndex() << "(sp)";
+    } else {
+      DCHECK(location.IsSIMDStackSlot());
+      stream << "4x" << location.GetStackIndex() << "(sp)";
     }
   }