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Updated reentrancy documentation

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Karol Stasiak 2018-08-01 18:49:15 +02:00
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docs/lang/reentrancy.md
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@ -59,7 +59,23 @@ and assigning all parameters to variables as soon as possible. This is slow thou
A function is interrupt-safe if it can be safely called, either directly or indirectly, A function is interrupt-safe if it can be safely called, either directly or indirectly,
simultaneously by the main code and by an interrupt routine. simultaneously by the main code and by an interrupt routine.
The only way to make a function interrupt-safe is to have no parameters and make all local variables stack-allocated. The only way to make a function interrupt-safe is:
* have either no parameters, or just one parameter passed via registers that is immediately assigned to a local stack-allocated variable
* if there is a parameter: enable optimizations
* make all local variables stack-allocated,
* have a return type that can be returned via registers.
The size limit on the parameter and the return type depends on architecture:
* for 6502-like architectures: 2 bytes
* for 8080-like architectures: 4 bytes
All built-in functions and operators are designed to be interrupt-safe.
# Reentrancy safety violations # Reentrancy safety violations