match_asm_constraints: Use copy_rtx where needed (PR88001)

The new insn here (temporarily) illegally shares RTL.  This fixes it.


	PR rtl-optimization/88001
	* function.c (match_asm_constraints_1): Don't invalidly share RTL.

From-SVN: r267122

gcc/ChangeLog

+2018-12-14  Segher Boessenkool  <segher@kernel.crashing.org>
+
+	PR rtl-optimization/88001
+	* function.c (match_asm_constraints_1): Don't invalidly share RTL.
+
 2018-12-14  Bin Cheng  <bin.cheng@linux.alibaba.com>
 
 	* auto-profile.c (afdo_annotate_cfg): Call update_max_bb_count even

gcc/function.c

@@ -6529,7 +6529,7 @@ match_asm_constraints_1 (rtx_insn *insn, rtx *p_sets, int noutputs)
       output_matched[match] = true;
 
       start_sequence ();
-      emit_move_insn (output, input);
+      emit_move_insn (output, copy_rtx (input));
       insns = get_insns ();
       end_sequence ();
       emit_insn_before (insns, insn);