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* corrected some spelling errors in the optimizations part

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* added another tip to get faster code
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Jonas Maebe 1998-12-14 19:05:20 +00:00
parent c91c9bb341
commit 91877d698d
1 changed files with 9 additions and 6 deletions
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docs/prog.tex
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@ -3060,12 +3060,12 @@ requested, things aren't aligned on 4-byte boundaries. When speed is
requested, things are aligned on 4-byte boundaries as much as possible.
\item Fast optimizations (\var{-O1}): activate the peephole optimizer
\item Slower optimizations (\var{-O2}): also activate the common subexpression
elimination (formaerly called the "reloading optimizer)
elimination (formerly called the "reloading optimizer")
\item Uncertain optimizations (\var{-Ou}): With this switch, the common subexpression
elimination algorithm can be forced into making uncertain optimizations.
Although you can enable uncertain optimizations in most cases, for people who
do not understand the follwong technical explanation, it might be the safes to
do not understand the following technical explanation, it might be the safest to
leave them off.
\begin{quote}
@ -3218,8 +3218,8 @@ when they cannot be used.
\end{description}
\section{Tips to get faster code}
Here some general tips for getting better code are presented. They are
mainly concerned with coding style.
Here some general tips for getting better code are presented. They
mainly concern coding style.
\begin{itemize}
\item Find a better algorithm. No matter how much you and the compiler
@ -3232,9 +3232,12 @@ using longint and cardinal variables.
\item Turn on the optimizer.
\item Write your if/then/else statements so that the code in the "then"-part
gets executed most of the time (improves the rate of successful jump prediction).
\item If you are allocating and disposing a lot of small memory blocks,
check out the heapblocks variable. (heapblocks are on by default from
release 0.99.8 on)
check out the heapblocks variable (heapblocks are on by default from
release 0.99.8 and later)
\item Profile your code (see the -pg switch) to find out where the
bottlenecks are. If you want, you can rewrite those parts in assembler.