mirror of
https://github.com/idapython/src
synced 2026-06-08 14:47:00 +00:00
Arnaud Diederen
71 lines
2.2 KiB
Python
71 lines
2.2 KiB
Python
"""
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summary: add a custom microcode instruction optimization rule
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description:
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Installs a custom microcode instruction optimization rule,
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to transform:
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x | ~x
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into
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-1
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To see this plugin in action please use be_ornot_be.idb
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level: advanced
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"""
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import ida_hexrays
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import ida_idaapi
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# recognize "x | ~x" and replace by -1
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class subinsn_optimizer_t(ida_hexrays.minsn_visitor_t):
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cnt = 0
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def visit_minsn(self): # for each instruction...
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ins = self.curins # take a reference to the current instruction
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# THE CORE OF THE PLUGIN IS HERE:
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# check the pattern "x | ~x"
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if ins.opcode == ida_hexrays.m_or and ins.r.is_insn(ida_hexrays.m_bnot) and ins.l == ins.r.d.l:
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if not ins.l.has_side_effects(): # avoid destroying side effects
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# pattern matched, convert to "mov -1, ..."
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ins.opcode = ida_hexrays.m_mov
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ins.l.make_number(-1, ins.r.size)
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ins.r = ida_hexrays.mop_t()
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self.cnt = self.cnt + 1 # number of changes we made
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return 0 # continue traversal
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# a custom instruction optimizer, boilerplate code
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class sample_optimizer_t(ida_hexrays.optinsn_t):
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def func(self, blk, ins, optflags):
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opt = subinsn_optimizer_t()
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ins.for_all_insns(opt)
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if opt.cnt != 0: # if we modified microcode,
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blk.mba.verify(True) # run the verifier
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return opt.cnt # report the number of changes
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# a plugin interface, boilerplate code
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class my_plugin_t(ida_idaapi.plugin_t):
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flags = ida_idaapi.PLUGIN_HIDE
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wanted_name = "optimize x|~x"
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wanted_hotkey = ""
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comment = ""
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help = ""
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def init(self):
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if ida_hexrays.init_hexrays_plugin():
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self.optimizer = sample_optimizer_t()
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self.optimizer.install()
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print("Installed sample optimizer for 'x | ~x'")
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return ida_idaapi.PLUGIN_KEEP # keep us in the memory
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def term(self):
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self.optimizer.remove()
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def run(self, arg):
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if arg == 1:
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return self.optimizer.remove()
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elif arg == 2:
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return self.optimizer.install()
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def PLUGIN_ENTRY():
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return my_plugin_t()
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