# ------------------------------------------------------------------------------
# Access to the CodeHawk Binary Analyzer Analysis Results
# Author: Henny Sipma
# ------------------------------------------------------------------------------
# The MIT License (MIT)
#
# Copyright (c) 2016-2020 Kestrel Technology LLC
#
# Permission is hereby granted, free of charge, to any person obtaining a copy
# of this software and associated documentation files (the "Software"), to deal
# in the Software without restriction, including without limitation the rights
# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
# copies of the Software, and to permit persons to whom the Software is
# furnished to do so, subject to the following conditions:
#
# The above copyright notice and this permission notice shall be included in all
# copies or substantial portions of the Software.
# 
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
# SOFTWARE.
# ------------------------------------------------------------------------------

import chb.asm.X86OpcodeBase as X
import chb.simulate.SimulationState as S
import chb.simulate.SimUtil as SU
import chb.simulate.SimValue as SV

class X86Mul(X.X86OpcodeBase):

    # tags: [ 'mul' ]
    # args: [ size, dst-op, src1-op, src2-op ]
    def __init__(self,x86d,index,tags,args):
        X.X86OpcodeBase.__init__(self,x86d,index,tags,args)

    def get_size(self): return int(self.args[0])

    def get_dst_operand(self): return self.x86d.get_operand(self.args[1])

    def get_src1_operand(self): return self.x86d.get_operand(self.args[2])

    def get_src2_operand(self): return self.x86d.get_operand(self.args[3])

    def get_operands(self):
        return  [ self.get_dst_operand(), self.get_src1_operand(),
                      self.get_src2_operand() ]

    # xdata: [ "a:vxxxx": lhs, rhs1, rhs2, product, product-simplified ]
    def get_annotation(self,xdata):
        (xtags,xargs,xprs) = xdata.get_xprdata()
        lhs = str(xprs[0])
        rhs = str(xprs[3])
        rrhs = str(xprs[4])
        rhs = X.simplify_result(xargs[3],xargs[4],rhs,rrhs)
        return lhs + ' = ' + rhs

    def get_lhs(self,xdata):
        (xtags,xargs,xprs) = xdata.get_xprdata()
        return [ xprs[0] ]

    def get_rhs(self,xdata):
        (xtags,xargs,xprs) = xdata.get_xprdata()
        return [ xprs[4] ]

    # --------------------------------------------------------------------------
    # Performs an unsigned multiplication of the first operand (destination
    # operand) and the second operand (source operand) and stores the result
    # in the destination operand. The destination operand is an implied operand
    # located in register AL, AX or EAX (depending on the size of the operand);
    # the source operand is located in a general-purpose register or a memory
    # location.
    #
    # The result is stored in register AX, register pair DX:AX, or register pair
    # EDX:EAX (depending on the operand size), with the high-order bits of the
    # product contained in register AH, DX, or EDX, respectively. If the high-order
    # bits of the product are 0, the CF and OF flags are cleared; otherwise,
    # the flags are set.
    #
    # Flags affected:
    # The OF and CF flags are set to 0 if the upper half of the result is 0;
    # otherwise, they are set to 1. The SF, ZF, AF, and PF flags are undefined.
    # --------------------------------------------------------------------------
    def simulate(self,iaddr,simstate):
        src1op = self.get_src1_operand()
        src2op = self.get_src2_operand()
        dstop = self.get_dst_operand()
        src1val = simstate.get_rhs(iaddr,src1op)
        src2val = simstate.get_rhs(iaddr,src2op)
        result = src1val.mul(src2val)
        simstate.set(iaddr,dstop,result)
        highresult = result.get_high_half()
        simstate.update_flag('CF',not highresult.is_zero())
        simstate.update_flag('OF',not highresult.is_zero())
        simstate.undefine_flag('SF')
        simstate.undefine_flag('ZF')
        simstate.undefine_flag('PF')

    
