re PR rtl-optimization/63384 (scheduler loops on endless fence list with -fselective-scheduling2 on x86)

gcc/

	PR rtl-optimization/63384
	* sel-sched.c (invoke_aftermath_hooks): Do not decrease issue_more
	on DEBUG_INSN_P insns.

testsuite/

	PR rtl-optimization/63384
	* g++.dg/pr63384.C: New test.

From-SVN: r234217