Optimize String Manipulation
The handling of string operations can affect the performance
of your program.
- When you store strings into allocated storage, align the
start of the string on a 4-byte boundary. This allows the
best performance of the string functions. The compiler
performs this alignment for all strings it allocates.
- Keep track of the length of your strings. If you know the
length of your string, you can use mem functions instead
of str functions For example, memcpy is faster than
strcpy because it does not have to search for the end of
the string.
- Avoid using strtok. Because this function is very
general, you can probably write a function more specific
to your application and get better performance.
- When manipulating strings using mem functions, the code
you generate will be faster if the count parameter is a
constant, rather than a variable.This is especially true
for small count values.
Strings are read-only by default. Placing strings into
read-only memory allows for certain types of optimizations and
also causes the compiler to put out only one copy of strings that
are used in more than one place. If you use the intrinsic string
functions, the compiler can better optimize them if it knows that
any string literals it is operating on will not be changed.
Note: You can explicitly set strings to read-only by
using #pragma strings
(readonly) in your source files or the /qro compiler option
to avoid changing your source files.

Overview of Optimization

Optimize Your Application