Sun Studio 12: C User's Guide

B.2.103 -xloopinfo

(SPARC) Shows which loops are parallelized and which are not. Gives a short reason for not parallelizing a loop. The -xloopinfo option is valid only if -xautopar, or -xparallel, or -xexplicitpar is specified; otherwise, the compiler issues a warning.

To achieve faster execution, this option requires a multiprocessor system. On a single-processor system, the generated code usually runs slower.