Implement target hook for loop unrolling

Implement target hook for loop unrolling

2010-04-08  Christian Borntraeger  <borntraeger@de.ibm.com>
            Wolfgang Gellerich  <gellerich@de.ibm.com>

        Implement target hook for loop unrolling
        * target.h (loop_unroll_adjust): Add a new target hook function.
        * target-def.h (TARGET_LOOP_UNROLL_ADJUST): Likewise.
        * doc/tm.texi (TARGET_LOOP_UNROLL_ADJUST): Document it.
        * config/s390/s390.c (TARGET_LOOP_UNROLL_ADJUST): Define it.
        (s390_loop_unroll_adjust): Implement the new target hook for s390.
        * loop-unroll.c (decide_unroll_runtime_iterations): Call loop unroll target hook
        (decide_unroll_stupid): Likewise.

Co-Authored-By: Wolfgang Gellerich <gellerich@de.ibm.com>
From-SVN: r158132