PR target/42894
	* varasm.c (force_const_mem): Store copy of x in desc->constant
	instead of x itself.
	* expr.c (emit_move_insn): Add a copy of y_cst instead of y_cst
	itself into REG_EQUAL note.

	* gcc.dg/tls/pr42894.c: New test.

From-SVN: r169370