vcs加载sdf文件时报了四种错误

往生无量劫

Warning-[SDFCOM_SWC] Simple Wire Connection
../output/DC/32bit_FPGA_with_Masked_AES/NP/0_7/Masked_AES_32bit_with_GF_Sbox_NP_with_CSE_0.sdf, 8831
module: XOR2X1, "instance: Mask_AES_enc_dec_testbench.AES_topmodule.round_Iround32.IRound32.Iaffine.Iaffine0.U11"
  SDF Warning: The path from
  round_Iround32.IRound32.Iaffine.Iaffine0.U11.Y to
  round_Iround32.IRound32.I_subBytes.sbox0.invMul8_0.mul_Mask4_0.U79.A doesn't
  have a simple wire connection, delay will still be annotated.

Warning-[SDFCOM_IWSBA] INTERCONNECT will still be annotated
../output/DC/32bit_FPGA_with_Masked_AES/NP/0_7/Masked_AES_32bit_with_GF_Sbox_NP_with_CSE_0.sdf, 8821
module: XOR2X1, "instance: Mask_AES_enc_dec_testbench.AES_topmodule.round_Iround32.IRound32.I_subBytes.sbox0.invMul8_0.add_Mask4_0.U5"
  SDF Warning: INTERCONNECT from
  round_Iround32.IRound32.I_subBytes.sbox0.invMul8_0.add_Mask4_0.U5.Y to
  round_Iround32.IRound32.I_subBytes.sbox0.invMul8_0.add_Mask4_1.U5.A has
  Instance at
  ../output/DC/32bit_FPGA_with_Masked_AES/NP/0_7/Masked_AES_32bit_with_GF_Sbox_NP_with_CSE_0.net:16007,
  delay will still be annotated.


Warning-[SDFCOM_INF] IOPATH not found
../output/DC/32bit_FPGA_with_Masked_AES/NP/0_7/Masked_AES_32bit_with_GF_Sbox_NP_with_CSE_0.sdf, 102974
module: XOR2X1, "instance: Mask_AES_enc_dec_testbench.AES_topmodule.round_Iround32.IRound32.I_subBytes.sbox0.invMul8_0.mul_Mask4_2.U65"
  SDF Warning: IOPATH from B to Y is not found.



Warning-[SDFCOM_NNTC] Need timing check option +neg_tchk
../output/DC/32bit_FPGA_with_Masked_AES/NP/0_7/Masked_AES_32bit_with_GF_Sbox_NP_with_CSE_0.sdf, 401151
module: DFFRHQX1, "instance: Mask_AES_enc_dec_testbench.AES_topmodule.mux_Imux32.Imux32.Mask_out_reg_reg_110_"
  SDF Error: Negative HOLD value replaced by 0.         
  Add +neg_tchk to consider Negative delay value.



  Total errors: 6539
          Total warnings: 46911


求大佬建议，尤其是最后一个