UVM_DEFAULT：all field operations turned on
------------------------ AYFS D K R P M C（细节见下）
UVM_DEFAULT='b000010101010101;
UVM_ALL_ON = 'b000000101010101;
两者基本函数都一样，不同之处在于BIT[10]，BIT[10]代表DEEP，object field will be deep copied，比较少用（后续更新）
A=ABSTRACT
Y=PHYSICAL
F=REFERENCE
S=SHALLOW
D=DEEP,object field will be deep copied;
K=PACK
R=RECORD
P=PRINT
M=COMPARE
C=COPY
标签：区别,DEFAULT,object,DEEP,field,UVM,BIT From： https://www.cnblogs.com/icer-dave/p/17115674.html