Handle failed jumps a little more loudly

README.md

@@ -47,17 +47,9 @@ The Medium Level IL functions at a significantly higher level than the Lifted IL
 
 This plugin has only been tested on 64-bit Ubuntu 16.04. However, since it does not rely on any strictly os-dependent code, it will likely work on other platforms.
 
-## Installation
-If available, this plugin uses PyQt5 to display the explanation window. If no working PyQt5 installation is found, it will fall back to using the `show_message_box` feature of the Binary Ninja API, which displays a window that behaves more or less the same, but is not resizable, and blocks any other interaction with Binary Ninja.
-1. [Optional]: Install PyQt5 for your platform (`apt install python-pyqt5` on Ubuntu. For other platforms, see [this guide](https://github.com/nbsdx/binja-ui-api/blob/master/HowToPyQt5.pdf).)
-2. Clone this repository into your [Binary Ninja Plugins Folder](https://github.com/Vector35/binaryninja-api/tree/dev/python/examples#loading-plugins)
-
 ## Contributing
 This plugin is designed to make it simple to add support for new LLIL instructions or additional architectures. See [CONTRIBUTING.md](https://github.com/ehennenfent/binja_explain_instruction/blob/master/CONTRIBUTING.md). If you come across any inaccuracies, feel free to file a pull request or create an issue.
 
 ## Open Source
 This plugin incorporates [code by Ryan Stortz (@withzombies)](https://gist.github.com/withzombies/d4f0502754407b22da02664d4eb2fbae) that is used to display information about the CPU state before the selected instruction is executed. See instruction_state.py
 
-## Dependencies
-* PyQt5 [Optional]
-* Binary Ninja

__init__.py

@@ -138,8 +138,8 @@ def explain_instruction(bv, addr):
     # Display what information we can calculate about the program state before the instruction is executed
     try:
         explain_window().state = get_state(bv, addr)
-    except AttributeError:
-        log_error("No instruction state support for this architecture")
+    except (AttributeError, TypeError) as e:
+        log_error("Failed to extract instruction state")
 
     explain_window().show()
 

instruction_state.py

@@ -57,7 +57,7 @@ def get_state(bv, addr):
 
     sp_max = func.get_reg_value_at(addr, sp).offset
     # TODO: What happens when sp_max is None?
-    for i in range(sp_max if sp_max is not None else 0, 1):
+    for i in range(sp_max, 1):
         out = func.get_stack_contents_at(addr, i, 1)
         if IsRegisterValueInteresting(out):
             output.append("[SP{:#x}] = {}".format(i, out))