CompilerAsserts.java

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package com.oracle.truffle.api;

/**
 * Assertions about the code produced by the Truffle compiler. All operations have no effect when
 * either executed in the interpreter or in the compiled code. The assertions are checked during
 * code generation and the Truffle compiler produces for failing assertions a stack trace that
 * identifies the code position of the assertion in the context of the current compilation.
 *
 * @since 0.8 or earlier
 */
public final class CompilerAsserts {
    private CompilerAsserts() {
    }

    /**
     * Assertion that this code position should never be reached during compilation. It can be used
     * for exceptional code paths or rare code paths that should never be included in a compilation
     * unit. See {@link CompilerDirectives#transferToInterpreter()} for the corresponding compiler
     * directive.
     * 
     * @since 0.8 or earlier
     */
    public static void neverPartOfCompilation() {
    }

    /**
     * Assertion that this code position should never be reached during compilation. It can be used
     * for exceptional code paths or rare code paths that should never be included in a compilation
     * unit. See {@link CompilerDirectives#transferToInterpreter()} for the corresponding compiler
     * directive.
     *
     * @param message text associated with the bailout exception
     * @since 0.8 or earlier
     */
    public static void neverPartOfCompilation(String message) {
    }

    /**
     * Assertion that the corresponding value is reduced to a constant during compilation.
     *
     * @param value the value that must be constant during compilation
     * @since 0.8 or earlier
     */
    public static <T> void compilationConstant(Object value) {
        if (!CompilerDirectives.isCompilationConstant(value)) {
            neverPartOfCompilation("Value is not compilation constant");
        }
    }

    /**
     * Assertion that the corresponding value is reduced to a constant during the initial partial
     * evaluation phase.
     *
     * @param value the value that must be constant during compilation
     * @since 0.8 or earlier
     */
    public static <T> void partialEvaluationConstant(Object value) {
    }
}