20 lines
944 B
Plaintext
20 lines
944 B
Plaintext
__undefined
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===========
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:title: Shellcode Compiler Runtime
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---------------------------------------------
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__undefined;
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---------------------------------------------
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This intrinsic can be used in place of any value. It gives undefined results, usually by omitting
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code. The runtime result will vary based on the choices of the optimizer and code generator. The compiler
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will typically leave the register or memory location being targeted in its original state, completely
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omitting any instructions that would have been required to update it. Any arithmetic performed with
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`__undefined` as part of the computation will optimized down to a single usage of the `__undefined`
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intrinsic, as the results are by definition undefined.
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One of the most common uses of this intrinsic is to exit the program while treating the exit code as
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a "don't care" value, using `exit(__undefined)`. A `main` function that returns `void` implicitly
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does this.
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