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Compiler Design: Difference between revisions
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→Control Flow Analysis
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* either b immediately follows a, and a does not end in an unconditional branch, | * either b immediately follows a, and a does not end in an unconditional branch, | ||
* or a ends in a branch, of which b is a potential target. | * or a ends in a branch, of which b is a potential target. | ||
Note that an indirect branch, without context information, trivializes all blocks (every instruction becomes a leader) and flows to them all from at least that point (an arborescence is | Note that an indirect branch, without context information, trivializes all blocks (every instruction becomes a leader) and flows to them all from at least that point (an arborescence is induced)! | ||
The directed multigraph defined by interpreting basic blocks as vertices, and flow relationships as edges, yields its control flow graph (CFG). A start node exists for each CFG, corresponding to the basic block whose header is the first instruction of the program. | The directed multigraph defined by interpreting basic blocks as vertices, and flow relationships as edges, yields its control flow graph (CFG). A start node exists for each CFG, corresponding to the basic block whose header is the first instruction of the program. | ||
