Induction Variable Substitution
Induction variable substitution is a compiler transformation to recognize variables which can be expressed as functions of the indices of enclosing loops and replace them with induction variables with the expressions involving loop indices.
This transformation makes the relationship between the variables and loop indices explicit, which helps other compiler analysis, such as dependence analysis.
Example.
Input code:
int c, i; c = 10; for (i=0; i<10; i++) { c = c + 5; // c is incremented by 5 for each loop iteration }Output code
int c, i; c = 10; for (i=0; i<10; i++) { c = 10 + 5*i; // c is explicitly expressed as a function of loop index }Read more about this topic: Induction Variable
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