Remove IRT entries and use the JRT entries.

-// Definitions for IRT (Interpreter Runtime)
-// (thread is an argument passed in to all these routines)
-
-#define IRT_ENTRY(result_type, header) \
- result_type header { \
- ThreadInVMfromJava __tiv(thread); \
- VM_ENTRY_BASE(result_type, header, thread) \
- debug_only(VMEntryWrapper __vew;)
-
-
-#define IRT_LEAF(result_type, header) \
- result_type header { \
- VM_LEAF_BASE(result_type, header) \
- debug_only(NoSafepointVerifier __nspv(true);)
-
-
-#define IRT_ENTRY_NO_ASYNC(result_type, header) \
- result_type header { \
- ThreadInVMfromJavaNoAsyncException __tiv(thread); \
- VM_ENTRY_BASE(result_type, header, thread) \
- debug_only(VMEntryWrapper __vew;)
-
-#define IRT_END }