When Modelsim simulates, it can automatically optimize the waveform that cannot be obtained

When using Modelsim to simulate Verilog code, Modelsim automatically optimizes the waveform that cannot be generated

The following simulation information:

vsim work.SDRAM_interface_tb
# vsim 
# Start time: 14:57:38 on Mar 28,2020
# ** Note: (vsim-8009) Loading existing optimized design _opt
# 
# Loading work.SDRAM_interface_tb(fast)

Then just stuck here.

Solution:

1. Enter the following script in the Transcript command window in Modelsim to cancel the optimization:

   vsim work.顶层模块名 -novopt    或者
   vsim -novopt 顶层模块名

2. 
   Uncheck Enable optimization under Modelsim software->Simulate->Start Simulation and click OK to start the simulation.