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@@ -1 +1,31 @@
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+(** Convert boolean operations to equivalent operations on different CiviC data
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+ types. *)
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+
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+(** This phase transforms operations on boolean values to equivalent operations
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+ no different data types. This transformation is necessary, because the CiviC
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+ VM does not define some operations for boolean arguments.
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+
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+ This phase also handles the first step of short-circuit evaluation, by
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+ transforming conjunction and disjunction operators into conditional
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+ operations of the form [a ? b : c]. This operation is supported by the
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+ assembly phase, which handles them similarly to if-else statements. The
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+ benefit of using conditional operations, is that thiese are still
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+ expressions. A transformation into actual if-else statements would retuire
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+ adding additional statements, which creates other problems which we will not
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+ discuss here.
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+
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+ The applied transformations are as follows:
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+{v b1 == b2 ==> (int)b1 == (int)b2
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+b1 != b2 ==> (int)b1 != (int)b2
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+b1 && b2 ==> b1 ? b2 : false
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+b1 || b2 ==> b1 ? true : b2
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+b1 + b2 ==> (bool)((int)b1 + (int)b2)
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+b1 * b2 ==> (bool)((int)b1 * (int)b2)
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+(bool)i ==> i != 0
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+(bool)f ==> f != 0.0
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+(int)b1 ==> b1 ? 1 : 0
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+(float)b1 ==> b1 ? 1.0 : 0.0 v}
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+ *)
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+
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+(** Main phase function, called by {!Main}. *)
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val phase : Main.phase_func
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Taddeus Kroes