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[SPCA] Fixes a few errors

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Janis Hutz
2026-01-25 08:11:16 +01:00
parent eb6240c26e
commit 0770c76ef3
11 changed files with 30 additions and 11 deletions
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4
semester3/spca/parts/00_asm/01_syntax/00_intro.tex
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@@ -1,6 +1,8 @@
\newpage
\subsection{The syntax}
There are two common styles: AT\&T syntax (common on UNIX) and Intel syntax (common on Windows)
There are two common styles: AT\&T syntax (common on UNIX) and Intel syntax (common on Windows).
The most obvious difference between the two is that they invert the order of operands,
i.e. where the AT\&T syntax has the destination as the second argument, the Intel syntax puts it first.
The state that is visible to us is:
\begin{itemize}

6
semester3/spca/parts/00_asm/02_dtype-dstruct/00_data-types.tex
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@@ -1,6 +1,6 @@
\subsection{Data types}
Assembly supports the following integer types (where GAS stands for GNU Assembly).
If they are signed or unsigned does not matter (as we have seen), so it's up to you to interpret them as one or the other
If they are signed or unsigned does not matter (as we will see in section \ref{sec:c-integers}), so it's up to you to interpret them as one or the other
\begin{tables}{llll}{Intel & GAS & Bytes & \lC}
byte & \texttt{b} & 1 & \texttt{[unsigned] char} \\
word & \texttt{w} & 2 & \texttt{[unsigned] short} \\
@@ -15,5 +15,5 @@ They are stored and operated on in floating point registers.
double & \texttt{l} & 8 & \texttt{double} \\
extended & \texttt{t} & 16 & \texttt{long double} \\
\end{tables}
Assembly does not support any aggregate types (such as arrays, structs, etc) natively.
You can however (obviously) make your own. In the following section we will cover how \lC\ datatypes are compiled into assembly.
Assembly does not support any aggregate types (such as arrays, structs, etc) natively. You can however (obviously) make your own.
In the following section we will cover how \lC\ datatypes are compiled into assembly.

3
semester3/spca/parts/00_asm/02_dtype-dstruct/03_nested-arrays.tex
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@@ -1,7 +1,8 @@
\newpage
\subsubsection{Nested / Multidimensional arrays, Struct arrays}
All of these arrays have similar underlying concepts in the way they are allocated, yet all are a bit different
\content{Common ideas} Each of the array's elements are allocated in contiguous regions of memory, with the elemnts also in contiguous regions of memory.
\content{Common ideas} Each of the array's elements are allocated in contiguous regions of memory, with the elements also in contiguous regions of memory.
(Imagine it as lining up all elements on a band, i.e. as going through the array in a nested loop and printing all the elements into a single line.)
The size of the array is determined by \texttt{n * sizeof(T)}, where \texttt{T} is the type of the elements of the array (or outer array).
This is what is different for the lot (as well as accessing elements):

7
semester3/spca/parts/00_asm/03_operations/02_condition-codes.tex
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@@ -20,6 +20,9 @@ and \texttt{OF} is set as above, where \texttt{t = a - b}.
Another instruction that is used is \texttt{testX src2, src1} (X again a size postfix, easier: \texttt{testX b, a}), and acts like computing \texttt{a \& b} and where \texttt{ZF} is set if \texttt{a \& b == 0}
and \texttt{SF} is set if \texttt{a \& b < 0}.
\content{Zeroing register} We can use a move instruction, but that is less efficient than using \texttt{xorl reg, reg}, where \texttt{reg} is the 32-bit version of the reg we want to zero.
\content{Zeroing register} We can use a move instruction, but that is less efficient than using \texttt{xorl reg, reg},
where \texttt{reg} is the 32-bit version of the reg we want to zero. This works because on 32-bit operations,
the upper 32 bit of the 64 bit register will be zeroed.
\content{Reading condition codes} To read condition codes, we can use the \texttt{setC} instructions, where the \texttt{C} is to be substituted by an element of table \ref{tab:condition-codes}
\content{Reading condition codes} To read condition codes, we can use the \texttt{setC} instructions,
where the \texttt{C} is to be substituted by an element of table \ref{tab:condition-codes}