2_isa/conds.tex

   1 \section{Conditions}
   2
   3 \begin{table}[ht]
   4         \centering
   5         \begin{tabular}{|c|c|c|}\hline
   6                 Bitcode & Condition             & Bits to test \\ \hline
   7                 0000    & equal / zero          & ZF = 0\\ \hline
   8                 0001    & not equal / not zero  & ZF = 1\\ \hline
   9                 0010    & not overflow          & OF = 0\\ \hline
  10                 0011    & overflow              & OF = 1\\ \hline
  11                 0100    & not carry             & CF = 0\\ \hline
  12                 0101    & carry                 & CF = 1\\ \hline
  13                 0110    & not signed / not neg. & SF = 0\\ \hline
  14                 0111    & signed / neg.         & SF = 1\\ \hline
  15                 1000    & below (?)             & \\ \hline
  16                 1001    & above (?)             & \\ \hline
  17                 1010    & greater than or equal & SF == OF\\ \hline
  18                 1011    & less than             & SF != OF \\ \hline
  19                 1100    & greater than          & (ZF == 0 $\wedge$ SF == OF) \\ \hline
  20                 1101    & less than or equal    & (ZF == 1 $\vee$ SF != OF) \\ \hline
  21                 1110    & never                 & \\ \hline
  22                 1111    & always                & \\ \hline
  23         \end{tabular}
  24         \caption{codierung von conditions}
  25 \end{table}
  26
  27 \begin{table}
  28         \centering
  29         \begin{tabular}{|l|c|c|c|c|} \hline
  30                 Bit  & 3  & 2  & 1  & 0  \\ \hline
  31                 Flag & SF & CF & OF & ZF \\ \hline
  32         \end{tabular}
  33         \caption{billig PSW bitorder}
  34 \end{table}