Paul Schlie wrote:
What about optimising x*2/2 to x?
Given that "C" requires the above be evaluated as (x*2)/2, as the language
specifies that the syntax defines the precedence of the operations, and that
no optimization should alter the behavior as specified by the program; I'd
say that unless it was known that the value range of x was between 0
and INT_MAX, the optimization is simply invalid.
the optimization is indeed valid
optimizations may most certainly alter behavior of undefined
code. think about uninitialized local variables.
