lra: fix spill_hard_reg_in_range clobber check

lra: fix spill_hard_reg_in_range clobber check

FROM..TO range might contain NOTE_INSN_DELETED insns, for which the
corresponding entries in lra_insn_recog_data[] are NULLs.  Example from
the problematic code from PR87596:

    (note 148 154 68 7 NOTE_INSN_DELETED)

lra_insn_recog_data[] is used directly only when the insn in question
is taken from insn_bitmap, which is not the case here.  In other
situations lra_get_insn_recog_data () guarded by INSN_P () or other
stricter predicate are used.  So we need to do this here as well.

A tiny detail worth noting: I put the INSN_P () check before the
insn_bitmap check, because I believe that insn_bitmap can contain only
real insns anyway.

gcc/ChangeLog:

2018-10-19  Ilya Leoshkevich  <iii@linux.ibm.com>

	PR rtl-optimization/87596
	* lra-constraints.c (spill_hard_reg_in_range): Use INSN_P () +
	lra_get_insn_recog_data () instead of lra_insn_recog_data[]
	for instructions in FROM..TO range.

gcc/testsuite/ChangeLog:

2018-10-19  Ilya Leoshkevich  <iii@linux.ibm.com>

	PR rtl-optimization/87596
	* gcc.target/i386/pr87596.c: New test.

From-SVN: r265306