% Posted c
true @$\lhd$@ -[c]
% Propagated c = true
c @$\mapsfrom$@ mkvar(0,1) @$\sep$@ []
true @$\lhd$@ +[c]
% Simplified bool_or(b1, true) = true
b2 @$\mapsfrom$@ bool_or(b1, c) @$\sep$@ []
true @$\lhd$@ +[b2]
% b1 became unused...
b1 @$\mapsfrom$@ int_gt(t, y) @$\sep$@ []
% causing t, then b0 and finally z to become unused
t @$\mapsfrom$@ z @$\sep$@ [b0]
b0 @$\mapsfrom$@ int_abs(x, z) @$\sep$@ []
z @$\mapsfrom$@ mkvar(-infinity,infinity) @$\sep$@ []