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Add the rest of the extended alu operations

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Andreas Traber 2015-12-22 16:13:20 +01:00
parent 5a0e624be7
commit cfc1a17419
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docs/datasheet/content/aluext.tex
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@ -257,3 +257,197 @@ Computes the absolute value of the signed 32-bit operand rs1.
\end{bytefield}
\end{center}
\textbf{Operation:} \texttt{rD = RotateRight(rs1, rs2)}
\subsection{p.exths rD, rs1}
\begin{center}
\begin{bytefield}[endianness=big,bitwidth=1.3em]{32}
\bitheader{31,25,24,20,19,15,14,12,11,7,6,0} \\
\bitbox{7}{ funct7 }
\bitbox{5}{ 00000 }
\bitbox{5}{ rs1 }
\bitbox{3}{ funct3 }
\bitbox{5}{ rd }
\bitbox{7}{ opcode } \\
\bitbox[]{7}{ 000 1000}
\bitbox[]{5}{ 00000 }
\bitbox[]{5}{ src1 }
\bitbox[]{3}{ 100 }
\bitbox[]{5}{ dest }
\bitbox[]{7}{ 011 0011 }
\end{bytefield}
\end{center}
\textbf{Operation:} \texttt{rD = Sext(rs1[15:0])}
\subsection{p.exthz rD, rs1}
\begin{center}
\begin{bytefield}[endianness=big,bitwidth=1.3em]{32}
\bitheader{31,25,24,20,19,15,14,12,11,7,6,0} \\
\bitbox{7}{ funct7 }
\bitbox{5}{ 00000 }
\bitbox{5}{ rs1 }
\bitbox{3}{ funct3 }
\bitbox{5}{ rd }
\bitbox{7}{ opcode } \\
\bitbox[]{7}{ 000 1000}
\bitbox[]{5}{ 00000 }
\bitbox[]{5}{ src1 }
\bitbox[]{3}{ 101 }
\bitbox[]{5}{ dest }
\bitbox[]{7}{ 011 0011 }
\end{bytefield}
\end{center}
\textbf{Operation:} \texttt{rD = Zext(rs1[15:0])}
\subsection{p.extbs rD, rs1}
\begin{center}
\begin{bytefield}[endianness=big,bitwidth=1.3em]{32}
\bitheader{31,25,24,20,19,15,14,12,11,7,6,0} \\
\bitbox{7}{ funct7 }
\bitbox{5}{ 00000 }
\bitbox{5}{ rs1 }
\bitbox{3}{ funct3 }
\bitbox{5}{ rd }
\bitbox{7}{ opcode } \\
\bitbox[]{7}{ 000 1000}
\bitbox[]{5}{ 00000 }
\bitbox[]{5}{ src1 }
\bitbox[]{3}{ 110 }
\bitbox[]{5}{ dest }
\bitbox[]{7}{ 011 0011 }
\end{bytefield}
\end{center}
\textbf{Operation:} \texttt{rD = Sext(rs1[7:0])}
\subsection{p.extbz rD, rs1}
\begin{center}
\begin{bytefield}[endianness=big,bitwidth=1.3em]{32}
\bitheader{31,25,24,20,19,15,14,12,11,7,6,0} \\
\bitbox{7}{ funct7 }
\bitbox{5}{ 00000 }
\bitbox{5}{ rs1 }
\bitbox{3}{ funct3 }
\bitbox{5}{ rd }
\bitbox{7}{ opcode } \\
\bitbox[]{7}{ 000 1000}
\bitbox[]{5}{ 00000 }
\bitbox[]{5}{ src1 }
\bitbox[]{3}{ 111 }
\bitbox[]{5}{ dest }
\bitbox[]{7}{ 011 0011 }
\end{bytefield}
\end{center}
\textbf{Operation:} \texttt{rD = Zext(rs1[7:0])}
\subsection{p.ff1 rD, rs1}
Returns position of first bit that is \texttt{1} starting from LSB, 32 if none.
\begin{center}
\begin{bytefield}[endianness=big,bitwidth=1.3em]{32}
\bitheader{31,25,24,20,19,15,14,12,11,7,6,0} \\
\bitbox{7}{ funct7 }
\bitbox{5}{ 00000 }
\bitbox{5}{ rs1 }
\bitbox{3}{ funct3 }
\bitbox{5}{ rd }
\bitbox{7}{ opcode } \\
\bitbox[]{7}{ 000 1000}
\bitbox[]{5}{ 00000 }
\bitbox[]{5}{ src1 }
\bitbox[]{3}{ 000 }
\bitbox[]{5}{ dest }
\bitbox[]{7}{ 011 0011 }
\end{bytefield}
\end{center}
\textbf{Operation:} \texttt{rD = FindFirst1(rs1)}
\subsection{p.fl1 rD, rs1}
Returns position of first bit that is \texttt{1} starting from MSB, 32 if none.
\begin{center}
\begin{bytefield}[endianness=big,bitwidth=1.3em]{32}
\bitheader{31,25,24,20,19,15,14,12,11,7,6,0} \\
\bitbox{7}{ funct7 }
\bitbox{5}{ 00000 }
\bitbox{5}{ rs1 }
\bitbox{3}{ funct3 }
\bitbox{5}{ rd }
\bitbox{7}{ opcode } \\
\bitbox[]{7}{ 000 1000}
\bitbox[]{5}{ 00000 }
\bitbox[]{5}{ src1 }
\bitbox[]{3}{ 001 }
\bitbox[]{5}{ dest }
\bitbox[]{7}{ 011 0011 }
\end{bytefield}
\end{center}
\textbf{Operation:} \texttt{rD = FindLast1(rs1)}
\subsection{p.clb rD, rs1}
Count leading bits in rs1, i.e. the number of consecutive \texttt{1} or
\texttt{0} bits from MSB.
\begin{center}
\begin{bytefield}[endianness=big,bitwidth=1.3em]{32}
\bitheader{31,25,24,20,19,15,14,12,11,7,6,0} \\
\bitbox{7}{ funct7 }
\bitbox{5}{ 00000 }
\bitbox{5}{ rs1 }
\bitbox{3}{ funct3 }
\bitbox{5}{ rd }
\bitbox{7}{ opcode } \\
\bitbox[]{7}{ 000 1000}
\bitbox[]{5}{ 00000 }
\bitbox[]{5}{ src1 }
\bitbox[]{3}{ 010 }
\bitbox[]{5}{ dest }
\bitbox[]{7}{ 011 0011 }
\end{bytefield}
\end{center}
\textbf{Operation:} \texttt{rD = CountLeadingBits(rs1)}
\subsection{p.cnt rD, rs1}
Count the number of bits set to \texttt{1} in rs1. This is also known as
population count.
\begin{center}
\begin{bytefield}[endianness=big,bitwidth=1.3em]{32}
\bitheader{31,25,24,20,19,15,14,12,11,7,6,0} \\
\bitbox{7}{ funct7 }
\bitbox{5}{ 00000 }
\bitbox{5}{ rs1 }
\bitbox{3}{ funct3 }
\bitbox{5}{ rd }
\bitbox{7}{ opcode } \\
\bitbox[]{7}{ 000 1000}
\bitbox[]{5}{ 00000 }
\bitbox[]{5}{ src1 }
\bitbox[]{3}{ 011 }
\bitbox[]{5}{ dest }
\bitbox[]{7}{ 011 0011 }
\end{bytefield}
\end{center}
\textbf{Operation:} \texttt{rD = PopCount(rs1)}