1 /*
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 3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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25 
26 package jdk.incubator.code.analysis;
27 
28 import jdk.incubator.code.*;
29 
30 /**
31  * Functionality to transform a code model into pure SSA form, replacing operations that declare variables and
32  * access them with the use of values they depend on or additional block parameters.
33  */
34 public final class SSA {
35     private SSA() {
36     }
37 
38     /**
39      * Applies an SSA transformation to an operation with bodies, replacing operations that declare variables and
40      * access them with the use of values they depend on or additional block parameters.
41      * <p>
42      * The operation should first be in lowered form before applying this transformation.
43      * <p>
44      * Note: this implementation does not currently work correctly when a variable is stored to within an exception
45      * region and read from outside as a result of catching an exception. In such cases a complete transformation may be
46      * not possible and such variables will need to be retained.
47      *
48      * @param nestedOp the operation with bodies
49      * @return the transformed operation
50      * @param <T> the operation type
51      */
52     public static <T extends Op & Op.Nested> T transform(T nestedOp) {
53         // @@@ property is used to test both impls
54         if (!"cytron".equalsIgnoreCase(System.getProperty("babylon.ssa"))) {
55             return SSABraun.transform(nestedOp);
56         } else {
57             return SSACytron.transform(nestedOp);
58         }
59     }
60 }