Loop Transformations

The loop transformation techniques include:

• loop normalization

• loop reversal

• loop interchange and permutation

• loop distribution

• loop fusion

• scalar replacement

• absence of loop-carried memory dependency with the IVDEP directive

• runtime data dependencies checking (Itanium®-based systems only)

The loop transformations listed above are supported by data dependence. The loop transformation techniques also include:

• induction variable elimination

• constant propagation

• copy propagation

• forward substitution

• and dead code elimination.

In addition to the loop transformations listed for both IA-32 and Itanium® architectures above, the Itanium architecture enables implementation of the collapsing techniques.