Debugger: Pretty print the name of a function when using lldb

This is achieved by calling "po" on an address value casted to a
simple function pointer type, regardless of the actual type of
the function pointer. lldb does not complain, and reports the
library where the function is defined, its name, and location
in the source code if available.

Change-Id: I23ccce62e33bcf213ccdcb55c9836d54333f3c86
Reviewed-by: hjk <hjk@qt.io>

share/qtcreator/debugger/lldbbridge.py

@@ -457,7 +457,7 @@ class Dumper(DumperBase):
                     self.listMembers(value, nativeType)
                 tdata.templateArguments = self.listTemplateParametersHelper(nativeType)
             elif code == lldb.eTypeClassFunction:
-                tdata.code = TypeCodeFunction,
+                tdata.code = TypeCodeFunction
             elif code == lldb.eTypeClassMemberPointer:
                 tdata.code = TypeCodeMemberPointer
 
@@ -649,6 +649,21 @@ class Dumper(DumperBase):
     def isMsvcTarget(self):
         return False
 
+    def prettySymbolByAddress(self, address):
+        try:
+            result = lldb.SBCommandReturnObject()
+            # Cast the address to a function pointer to get the name and location of the function.
+            expression = 'po (void (*)()){}'
+            self.debugger.GetCommandInterpreter().HandleCommand(expression.format(address), result)
+            output = ''
+            if result.Succeeded():
+                output = result.GetOutput().strip()
+            if output:
+                return output
+        except:
+            pass
+        return '0x%x' % address
+
     def qtVersionAndNamespace(self):
         for func in self.target.FindFunctions('qVersion'):
             name = func.GetSymbol().GetName()