1. A method for execution on an SISD machine for ascertaining any source code procedural language statements which are amenable to being compiled into object code for execution on an SIMD machine, comprising the steps of: (a) mapping in said SISD machine said source code statements onto n counterpart nodes of a dependence graph, said graph (FIGS. 2A, 2B) having directed edges, the edges connecting nodes according to dependences and selectively forming closed traverses or loops, the edges further being selectively nested and labeled with a level number (FIGS. 2A, 3A, edges labeled 4) indicating the level of any node (1, 2,. .. , n) causing the dependence, each edge (FIG. 2B) being further labeled with indicia as to whether it is either innermost-sensitive or innermost-preventing; (b) identifying in said SISD machine the statements at the nodes bounding each level of any innermost-sensitive and loop-independent edges of the graph, if at that level, the edges having the labeled dependences can be reordered to operate as an innermost loop and if there are no cycles in the graph after recording; and (c) generating in said SISD machine object code obtained from any statements identified in step (b).