Blocks

Blocks are parts of a function. They are in itself dict with a mapping from instruction address to instruction.

Finding a block

import quokka

# Load the program and get a function
prog = quokka.Program('docs/samples/qb-crackme.quokka', 'docs/samples/qb-crackme')
func = prog.fun_names['level_1']

block_start: int = 0x80494e8

# Method 1: Get a block through the function (dict-style access)
block = func[block_start]

# Method 2: Get a block from an instruction
inst = prog.get_instruction(block_start)
block = inst.block

Block attributes

It should be no suprise that a Block is also a mapping. Indeed, it holds a mapping from address to Instructions.

However, it still has some properties

CFG

A block maintains a list of successors and predecessors (from the CFG).

successor: int
for successor in block.successors:
   assert(successor in block.parent)

Strings, constants and comments

Strings, constants (and other data) are accessible with the eponyms attributes. Moreover, if a comment has been defined in the disassembler, it is accessible through comments.

Type

Basic blocks have types which are exported by quokka. Use block.type to access it.