Add lldbToolBox.py scaffolding in ./utils for adding lldb python helpers to use when debugging swift.

Currently this file just imports lldbDataFormatters.py from llvm without the
user needing to know about it. I want to begin adding more utility (for
instance, graphing an assembly CFG without needing to copy/paste) to this file.

To use this in lldb run:

command script import $SWIFT_DIR/utils/lldbToolBox.py

Author: gottesmm

utils/lldbToolBox.py

@@ -0,0 +1,30 @@
+"""
+LLDB Helpers for working with the swift compiler.
+
+Load into LLDB with 'command script import /path/to/lldbToolBox.py'
+
+This will also import LLVM data formatters as well, assuming that llvm is next
+to the swift checkout.
+"""
+
+import os
+
+REPO_BASE = os.path.abspath(os.path.join(__file__, os.pardir, os.pardir,
+                                         os.pardir))
+SWIFT_REPO = os.path.join(REPO_BASE, "swift")
+LLVM_REPO = os.path.join(REPO_BASE, "llvm")
+LLVM_DATAFORMATTER_PATH = os.path.join(LLVM_REPO, "utils",
+                                       "lldbDataFormatters.py")
+
+
+def import_llvm_dataformatters(debugger):
+    if not os.access(LLVM_DATAFORMATTER_PATH, os.F_OK):
+        print("WARNING! Could not find LLVM data formatters!")
+        return
+    cmd = 'command script import {}'.format(LLVM_DATAFORMATTER_PATH)
+    debugger.HandleCommand(cmd)
+    print("Loaded LLVM data formatters.")
+
+
+def __lldb_init_module(debugger, internal_dict):
+    import_llvm_dataformatters(debugger)