make-any select instr

book.tex

@@ -10377,51 +10377,31 @@ C_4 & ::= & \gray{ \PROGRAMDEFS{\itm{info}}{\LP\Def\ldots\RP} }
 \section{Instruction Selection}
 \label{sec:select-r6}
 
-\paragraph{Inject}
-
-We recommend compiling an \key{inject} as follows if the type is
-\key{Integer} or \key{Boolean}.  The \key{salq} instruction shifts the
-destination to the left by the number of bits specified its source
-argument (in this case $3$, the length of the tag) and it preserves
-the sign of the integer. We use the \key{orq} instruction to combine
-the tag and the value to form the tagged value.  \\
-\begin{tabular}{lll}
-\begin{minipage}{0.4\textwidth}
-\begin{lstlisting}
-(assign |\itm{lhs}| (inject |$e$| |$T$|))
-\end{lstlisting}
-\end{minipage}
-&
-$\Rightarrow$
-&
-\begin{minipage}{0.5\textwidth}
+\paragraph{Make-Any}
+
+We recommend compiling the \key{make-any} primitive as follows if the
+tag is for \key{Integer} or \key{Boolean}.  The \key{salq} instruction
+shifts the destination to the left by the number of bits specified its
+source argument (in this case $3$, the length of the tag) and it
+preserves the sign of the integer. We use the \key{orq} instruction to
+combine the tag and the value to form the tagged value.  \\
 \begin{lstlisting}
+(Assign |\itm{lhs}| (Prim 'make-any (list |$e$| (Int |$\itm{tag}$|))))
+|$\Rightarrow$|
 (movq |$e'$| |\itm{lhs}'|)
 (salq (int 3) |\itm{lhs}'|)
-(orq (int |$\itm{tagof}(T)$|) |\itm{lhs}'|)
+(orq (int |$\itm{tag}$|) |\itm{lhs}'|)
 \end{lstlisting}
-\end{minipage}
-\end{tabular}  \\
 The instruction selection for vectors and procedures is different
 because their is no need to shift them to the left. The rightmost 3
 bits are already zeros as described above. So we just combine the
 value and the tag using \key{orq}.  \\
-\begin{tabular}{lll}
-\begin{minipage}{0.4\textwidth}
-\begin{lstlisting}
-(assign |\itm{lhs}| (inject |$e$| |$T$|))
-\end{lstlisting}
-\end{minipage}
-&
-$\Rightarrow$
-&
-\begin{minipage}{0.5\textwidth}
 \begin{lstlisting}
+(Assign |\itm{lhs}| (Prim 'make-any (list |$e$| (Int |$\itm{tag}$|))))
+|$\Rightarrow$|
 (movq |$e'$| |\itm{lhs}'|)
 (orq (int |$\itm{tagof}(T)$|) |\itm{lhs}'|)
 \end{lstlisting}
-\end{minipage}
-\end{tabular} 
 
 \paragraph{Tag of Any}