Fixed bug in x86-atom fast interpreter. Adds guard for potential null pointer.
Adds guard for potential null pointer when checking for debugger active on return from method.

Change-Id: Iaef2b6815fe6c64450cc0cc36f8920e4c38f40e6
diff --git a/vm/mterp/out/InterpAsm-x86-atom.S b/vm/mterp/out/InterpAsm-x86-atom.S
index 9d384dd..5db130e 100644
--- a/vm/mterp/out/InterpAsm-x86-atom.S
+++ b/vm/mterp/out/InterpAsm-x86-atom.S
@@ -18237,7 +18237,10 @@
     movl        rGLUE, rINST            # %ecx<- pMterpGlue
     movl        offGlue_pSelfSuspendCount(rINST), %edx # %ebx<- pSuspendCount (int)
     movl        offGlue_pDebuggerActive(rINST), %eax # %eax<- pDebuggerActive
+    testl       %eax, %eax
+    je          5f
     movl        (%eax), %eax            # %eax<- get debuggerActive (boolean)
+5:
     and         $7, %eax               # %eax<- mask for boolean (just how many bits does it take?)
     cmp         $0, (%edx)             # check if suspend is pending
     jne         2f                      # handle suspend
diff --git a/vm/mterp/x86-atom/footer.S b/vm/mterp/x86-atom/footer.S
index cb9970d..20acfb9 100644
--- a/vm/mterp/x86-atom/footer.S
+++ b/vm/mterp/x86-atom/footer.S
@@ -353,7 +353,10 @@
     movl        rGLUE, rINST            # %ecx<- pMterpGlue
     movl        offGlue_pSelfSuspendCount(rINST), %edx # %ebx<- pSuspendCount (int)
     movl        offGlue_pDebuggerActive(rINST), %eax # %eax<- pDebuggerActive
+    testl       %eax, %eax
+    je          5f
     movl        (%eax), %eax            # %eax<- get debuggerActive (boolean)
+5:
     and         $$7, %eax               # %eax<- mask for boolean (just how many bits does it take?)
     cmp         $$0, (%edx)             # check if suspend is pending
     jne         2f                      # handle suspend