Generate code for
a < b or c < d and e < f
Using the rules given in the previous two slides, we finally get the values of E.t and E.f by bottom up evaluation of the tree.
from E => E1 or M E 2
{ backpatch(E 1 .falselist, M.quad); ...}
=>
{ backpatch({101}, 102); ...}
gives
101: goto 102
from E => E1 and M E 2
{ backpatch(E 1 .truelist, M.quad); ...}
=>
{ backpatch({102}, 104); ...} gives
102: if c < d goto 104
Note that:
. the entire expression is true if the gotos of statements 100 or 104 are reached,
. the entire expression is false if the gotos of statements 103 or 105 are reached, and
. these targets will be filled in later when the action depending on the true/false is known.
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