Apr 19, 2016 · how to draw a control flow graph for the above code segment? Thanks in advance :) I am studying for a test on this and it's still kind of vague, so I might be wrong, but I think it should be this: O< /| \ >O. Please let me know if you got the same result, or if the graph is unclear I'll make a proper one.

• Combining two loops together (loop fusion) • Switching the order of a nested loop ( loop interchange ) • Completely changing the traversal order of a loop ( loop

A control flow graph is typically constructed by identifying leaders and target labels of loops. Hence, there is a possibility for this control flow graph to be reduced to make it an optimized one.

Unless two loops have the same header, they are disjoint or one is nested within the other. A nested loop is an inner loop if it contains no other loop. Algorithm 35.1 elucidates the construction of natural loop for any control flow graph. Algorithm 35.1 – Natural loop identification . Input: A flow graph G and a back edge n à d

Nov 1, 2017 · With the addition of these five control-flow primitives, high-level programming constructs such as cond and while_loop can now be compiled into dataflow graphs that can be executed by TensorFlow runtime.

•Structured control-flow constructs give rise to reducible CFGs •Value of reducibility: –Dominance useful in identifying loops –Simplifies code transformations (every loop has a single header) –Permits interval analysis

Normal control-flow constructs produce reducible flow graphs with the number of back edges at most the nesting depth of loops. Nesting depth tends to be small.

Disjoint and Nested Loops • Property: for any two natural loops in the flow graph, one of the following is true: 1. They are disjoint 2. They are nested 3. They have the same header • Eliminate alternative 3: if two loops have the same header and none is nested in the other, combine all nodes into a single loop 1 23 Two loops: {1,2} and {1,3}

Assuming that any two loops only intersect when one is nested inside the other, the loops in the CFG form a control tree in which the nodes are loops and the edges define the nesting relationship. Control-flow analysis builds on the key idea of …

What does a loop look like in a CFG? Nested Loops. Control-flow graphs may contain many loops. Loops may contain other loops: Loop Nesting Tree: We can abstract the program as the tree of loops it contains (if we only care about the loops). Once we do this, we can optimize all of the loops, starting from the ones with the deepest nesting.