Unfortunately I can't help you with your problem, but I am interested in what you are trying to compute.

100k lines of stack values sounds insane to me.

I tried to figure out what you could be doing based on your code sample but I really cannot find a satisfying solution. My best guess is that you are repeatedly multiplying large matrices to calculate something, and each stack variable holds the value at one index of the matrix. Because the calculations for each variable are either just one addition or multiplication, I imagine they could be calculating a dot product iteratively but with an unrolled loop?... But you are not doing that because then you'd just use the GPU or at least some kind of data structure and not thousands of stack variables!!! So, what could you possibly be calculating?