Avoid exponential execution time behavior in arith_expr_type() #971
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arith_expr_type() queries the expression type of its two child nodes up to two times. Since the child nodes might also need to query their child nodes expression type to determine their own this can lead to an exponential runtime. For complex expressions this can easily result in very long elaboration time. Avoid this by querying the expression type only once for each child node. Signed-off-by: Lars-Peter Clausen <[email protected]>
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arith_expr_type() queries the expression type of its two child nodes up to two times. Since the child nodes might also need to query their child nodes expression type to determine their own this can lead to an exponential runtime.
For complex expressions this can easily result in very long elaboration time.
Avoid this by querying the expression type only once for each child node.
Resolves #967