errata ch. 2 from Michael Vanier

book.tex

@@ -1150,7 +1150,7 @@ code~\citep{Intel:2015aa}. The subset, named \LangVar{}, includes
 integer arithmetic and local variable binding.  We often refer to
 x86-64 simply as x86.  The chapter begins with a description of the
 \LangVar{} language (Section~\ref{sec:s0}) followed by an introduction
-to of x86 assembly (Section~\ref{sec:x86}). The x86 assembly language
+to x86 assembly (Section~\ref{sec:x86}). The x86 assembly language
 is large so we discuss only the instructions needed for compiling
 \LangVar{}. We introduce more x86 instructions in later chapters.
 After introducing \LangVar{} and x86, we reflect on their differences
@@ -1498,14 +1498,14 @@ $\ldots$ are used to indicate a sequence of items, e.g., $\Instr
 \ldots$ is a sequence of instructions.\index{instruction}
 %
 An x86 program is stored in the computer's memory.  For our purposes,
-the computer's memory is as a mapping of 64-bit addresses to 64-bit
+the computer's memory is a mapping of 64-bit addresses to 64-bit
 values.  The computer has a \emph{program counter} (PC)\index{program
   counter}\index{PC} stored in the \code{rip} register that points to
 the address of the next instruction to be executed.  For most
 instructions, the program counter is incremented after the instruction
 is executed, so it points to the next instruction in memory.  Most x86
 instructions take two operands, where each operand is either an
-integer constant (called \emph{immediate value}\index{immediate
+integer constant (called an \emph{immediate value}\index{immediate
   value}), a \emph{register}\index{register}, or a memory location.
 
 \newcommand{\allregisters}{\key{rsp} \mid \key{rbp} \mid \key{rax} \mid \key{rbx} \mid \key{rcx}
@@ -1598,7 +1598,7 @@ main:
 \label{fig:p0-x86}
 \end{figure}
 
-The x86 assembly language varies in a couple ways depending on what
+The x86 assembly language varies in a couple of ways depending on what
 operating system it is assembled in. The code examples shown here are
 correct on Linux and most Unix-like platforms, but when assembled on
 Mac OS X, labels like \key{main} must be prefixed with an underscore,
@@ -1714,7 +1714,7 @@ programs, so we define an abstract syntax for x86 in
 Figure~\ref{fig:x86-int-ast}. We refer to this language as
 \LangXInt{}. The main difference compared to the concrete syntax of
 \LangXInt{} (Figure~\ref{fig:x86-int-concrete}) is that labels are not
-allowed in front of every instructions. Instead instructions are
+allowed in front of every instruction. Instead instructions are
 grouped into \emph{blocks}\index{block}\index{basic block} with a
 label associated with every block, which is why the \key{X86Program}
 struct includes an alist mapping labels to blocks. The reason for this
@@ -1771,7 +1771,7 @@ and x86 assembly? Here are some of the most important ones:
 
 \item[(b)] An argument of an \LangVar{} operator can be a deeply-nested
   expression, whereas x86 instructions restrict their arguments to be
-  integers constants, registers, and memory locations.
+  integer constants, registers, and memory locations.
 
 \item[(c)] The order of execution in x86 is explicit in the syntax: a
   sequence of instructions and jumps to labeled positions, whereas in
@@ -1781,7 +1781,7 @@ and x86 assembly? Here are some of the most important ones:
 \item[(d)] A program in \LangVar{} can have any number of variables
   whereas x86 has 16 registers and the procedure calls stack.
 
-\item[(e)] Variables in \LangVar{} can overshadow other variables with the
+\item[(e)] Variables in \LangVar{} can shadow other variables with the
   same name. In x86, registers have unique names and memory locations
   have unique addresses.
 \end{enumerate}
@@ -2083,10 +2083,10 @@ in the support code.
 
 \begin{exercise}
 \normalfont % I don't like the italics for exercises. -Jeremy
-
+\label{ex:Rvar}
 Create five \LangVar{} programs that exercise the most interesting
 parts of the \key{uniquify} pass, that is, the programs should include
-\key{let} forms, variables, and variables that overshadow each other.
+\key{let} forms, variables, and variables that shadow each other.
 The five programs should be placed in the subdirectory named
 \key{tests} and the file names should start with \code{var\_test\_}
 followed by a unique integer and end with the file extension
@@ -2175,7 +2175,7 @@ functions, \code{rco-atom} and \code{rco-exp}. The idea is to apply
 apply \code{rco-exp} to subexpressions that do not.  Both functions
 take an \LangVar{} expression as input.  The \code{rco-exp} function
 returns an expression.  The \code{rco-atom} function returns two
-things: an atomic expression and alist mapping temporary variables to
+things: an atomic expression and an alist mapping temporary variables to
 complex subexpressions. You can return multiple things from a function
 using Racket's \key{values} form and you can receive multiple things
 from a function call using the \key{define-values} form. If you are
@@ -2250,8 +2250,8 @@ Implement the \code{remove-complex-opera*} function in
 \code{compiler.rkt}.
 %
 Create three new \LangInt{} programs that exercise the interesting
-code in the \code{remove-complex-opera*} pass (Following the same file
-name guidelines as before.).
+code in the \code{remove-complex-opera*} pass.  Follow the guidelines
+regarding file names described in Exercise~\ref{ex:Rvar}.
 %
 In the \code{run-tests.rkt} script, add the following entry to the
 list of \code{passes} and then run the script to test your compiler.
@@ -2260,7 +2260,7 @@ list of \code{passes} and then run the script to test your compiler.
 \end{lstlisting}
 While debugging your compiler, it is often useful to see the
 intermediate programs that are output from each pass. To print the
-intermeidate programs, place the following before the call to
+intermediate programs, place the following before the call to
 \code{interp-tests} in \code{run-tests.rkt}.
 \begin{lstlisting}
 (debug-level 1)  
@@ -2401,7 +2401,7 @@ recommend implementing the \code{select-instructions} with
 three auxiliary functions, one for each of the non-terminals of
 \LangCVar{}: $\Atm$, $\Stmt$, and $\Tail$.
 
-The cases for $\Atm$ are straightforward, variables stay
+The cases for $\Atm$ are straightforward; variables stay
 the same and integer constants are changed to immediates:
 $\INT{n}$ changes to $\IMM{n}$.