The SimGrid model checker uses memory introspection (of the heap,
stack and global variables) in order to detect the equality of the
state of a distributed application at the different nodes of its
execution graph. One difficulty is to deal with uninitialised
variables. The uninitialised global variables are usually not a big
problem as their initial value is 0. The heap variables are dealt with
by memseting to 0 the content of the buffers returned by malloc
and friends. The case of uninitialised stack variables is more
problematic as their value is whatever was at this place on the stack
before. In order to evaluate the impact of those uninitialised
variables, we would like to clean each stack frame before using
them. This could be done with a LLVM plugin. Here is my first attempt
to write a LLVM pass to modify the code of a function.
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Adding a basic LLVM pass
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