The following patch solves PR63448.  The problem is described on

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63448

   The patch is safe and was bootstrapped and tested on x86/x86-64.

   Committed as rev. 216270 to the trunk and as rev. 216271 to gcc-4.9 
branch.

2014-10-15  Vladimir Makarov  <vmakarov@redhat.com>

         PR rtl-optimization/63448
         * lra-int.h (LRA_MAX_CONSTRAINT_ITERATION_NUMBER): Remove.
         (LRA_MAX_ASSIGNMENT_ITERATION_NUMBER): New.
         (LRA_MAX_INHERITANCE_PASSES): Use it.
         (lra_constraint_iter_after_spill): Remove.
         (lra_assignment_iter): New.
         (lra_assignment_iter_after_spill): New.
         * lra-assigns.c (lra_assignment_iter): New.
         (lra_assignment_iter_after_spill): New.
         (former_reload_pseudo_spill_p): New.
         (spill_for): Set up former_reload_pseudo_spill_p.
         (setup_live_pseudos_and_spill_after_risky): Ditto.
         (assign_by_spills): Ditto.
         (lra_assign): Increment lra_assignment_iter.  Print the iteration
         number.  Reset former_reload_pseudo_spill_p.  Check
         lra_assignment_iter_after_spill.
         * lra.c (lra): Remove lra_constraint_iter_after_spill.  Initialize
         lra_assignment_iter and lra_assignment_iter_after_spill.
         * lra-constraints.c (lra_constraint_iter_after_spill): Remove.
         (lra_constraints): Remove code with
         lra_assignment_iter_after_spill.

2014-10-15  Vladimir Makarov  <vmakarov@redhat.com>

         PR rtl-optimization/63448
         * gcc.target/i386/pr63448.c: New test.