Reordering instructions

Question

I have a question about reordering legal instructions in C # /. NET

Let's start with this example. We have this method defined in some class, where _a, _b and _c are fields.

int _a;
int _b;
int _c;
void Foo()
{
   _a = 1; // Write 1
   _b = 1; // Write 2
   _c = 1; // Write 3
}

And our calling environment will look something like this.

//memory operations
ClassInstance.Foo();
//memory operations

I wonder what kind of legal team reorganization is possible when this method call is built in against the function call. In particular, I am wondering if / when it is legal to reorder memory operations inside Foo () with memory operations outside it (from our previous example, memory operations).

Also, a function call (no built-in), in a sense, "creates memory barriers." As in the case, memory operations that occur before or after a function call cannot be redirected to memory operations in a function call.

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Answer 1

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Answer 2

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void Foo()
{
   ↑
   _a = 1; // Write 1
   ↑
   _b = 1; // Write 2
   ↑
   _c = 1; // Write 3
}

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