re PR rtl-optimization/69014 (gcc.c-torture/execute/991023-1.c FAILs with -Os -fmodulo-sched -fno-tree-vrp)

PR rtl-opt/69014

  * loop-doloop.c (record_reg_sets): New.
  (doloop_optimize): Reject the transform if the sequence
  clobbers registers live at the end of the loop block.
  (doloop_optimize_loops): Enable df_live if needed.

From-SVN: r232395