get_operand
LLVMValueRef result = get_operand(fn, insn->type, pseudo);
src2 = get_operand(fn, insn->type, insn->src2);
src3 = get_operand(fn, insn->type, insn->src3);
func = get_operand(fn, ctype, insn->func);
v = get_operand(fn, insn->type, insn->phi_src);
src = get_operand(fn, otype, insn->src);
src = get_operand(fn, otype, insn->src);
src = get_operand(fn, otype, insn->src);