Beginner Compilers & Programming Language Theory
Q20 / 100

What is SSA (Static Single Assignment) form?

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Incorrect.

The correct answer is B) An IR form where every variable is defined (assigned) exactly once, with φ-functions merging values at control flow joins

B

Correct Answer

An IR form where every variable is defined (assigned) exactly once, with φ-functions merging values at control flow joins

Explanation

SSA (Rosen et al., 1988): x₁=...; x₂=...; y=x₁+x₂. φ-functions at join points: x₃=φ(x₁,x₂) depending on control flow. Makes data flow obvious, simplifies optimizations (DCE, constant propagation, LICM).

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