[LLDB] Added support for PHI nodes to IR interpreter

This allows expressions such as 'i == 1 || i == 2` to be executed using the IR interpreter, instead of relying on JIT code injection (which may not be available on some platforms).

Patch by cameron314

Differential Revision: http://reviews.llvm.org/D19124

llvm-svn: 269340
diff --git a/lldb/source/Commands/CommandObjectExpression.h b/lldb/source/Commands/CommandObjectExpression.h
index 312e9fe6..3445aef 100644
--- a/lldb/source/Commands/CommandObjectExpression.h
+++ b/lldb/source/Commands/CommandObjectExpression.h
@@ -57,6 +57,7 @@
         bool        top_level;
         bool        unwind_on_error;
         bool        ignore_breakpoints;
+        bool        allow_jit;
         bool        show_types;
         bool        show_summary;
         bool        debug;