mirror of https://github.com/nmlgc/ReC98.git
18 lines
774 B
Markdown
18 lines
774 B
Markdown
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## Limits of decompilability
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### `MOV BX, SP`-style functions, no stack frame
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These almost certainly weren't compiled from C. By disabling stack frames
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using `#pragma option -k-`, it *might* be possible to still get the exact same
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code out of Turbo C++ – even though it will most certainly look horrible, and
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barely more readable than assembly (or even less so), with tons of inline ASM
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and register pseudovariables. However, it's futile to even try if the function
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contains one of the following:
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* A reference to the `DI` register. In that case, Turbo C++ always inserts a
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`PUSH DI` at the beginning (before the `MOV BX, SP`), and a `POP DI` before
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returning.
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**Certainty:** Confirmed through reverse-engineering `TCC.EXE`, no way
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around it.
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