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Stack pointer operation (enables putting putd in std.porth)
#117
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the ref operation pushes a pointer to the variable that is currently on the top of the stack. (Only works in compilation mode, but it sould be trivial to implement it in simulation mode if real pointers are used for `mem` after the bootstrapping.)
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Stack should be used for storing values that size know in compile time. |
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you can alternatively call the mmap syscall and get some memory, this is obviously a bit overkill but unless there isnt any malloc functionality this is the only way to not clobber any memory. Also don forget to call munmap |
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yep, makes sense to me. |
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here another way you can implement putd without mem |
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A simple operation that pushes a pointer to the element that is currenlty on the top of the stack.
With this functionality it's possible to allocate a temporary buffer on the stack by repeatedly pushing 0, and this enables to implement putd without a static buffer in memory, so putd can now be in the standard library.
As a sidenote, building
gol.porthwill now fail due to the macro name collision.There is one drawback, and that is that this will create a discrepancy between simulation and compilation, as there is no easy way to implement this in python I think.
Assuming that the stack is contiguous in memory in the bootstrapped version, there should really be no problem after that.