E  E1 or M E 2
backpatch(E 1 .falselist, M.quad)
E.truelist = merge(E1 .truelist, E2 .truelist)
E.falselist = E2 .falselist
E E 1 and M E2
backpatch(E1 .truelist, M.quad)
E.truelist = E 2 .truelist
E.falselist = merge(E1 .falselist, E2 .falselist)
E not E1
E.truelist = E 1 falselist
E.falselist = E1 .truelist
E ( E 1 )
E.truelist = E 1 .truelist
E.falselist = E1 .falselist
This is the backpatching translation scheme, continued through to the next slide.
E E1 or M E2
In this case
. if E1 is false then E2 will be looked into. Hence backpatch(E 1 .falselist, M.quad)
. If one of E1 or E2 is true then E is true, hence E.truelist = merge(E 1 .truelist, E2 .truelist)
. If E2 is checked then E1 must have been found to be false, hence Es falselist will be same as E1s falselist. Hence E.falselist = E2 .falselist
E E 1 and M E 2
. In this case if E1 is true then E2 will be looked into. Hence backpatch(E1 .truelist, M.quad)
. If one of E1 or E2 is false then E is false, hence E.falselist = merge(E1 .falselist, E 2 .falselist)
. If E2 checked then E1 must have been found to be true, hence Es truelist will be same as E2s truelist. Hence E.truelist = E2 .truelist
Similarly we can conclude for other two cases given above.
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