Von: Thomas Zimmermann Betreff: [SDL] [PATCH] Make static variables const Datum: Tue, 19 May 2009 19:45:37 +0200 Hi, this is a set of simple changes which make some of SDL's internal static arrays constant. The purpose is to shrink the number of write-able static bytes and thus increase the number of memory pages shared between SDL applications. The patch set is against trunk@4513. Each of the attached patch files is specific to a sub-system. The set is completed by a second mail, because of the list's 40 KiB limit. The files readelf-r4513.txt and readelf-const-patch.txt where made by calling 'readelf -S libSDL.so'. They show the difference in ELF sections without and with the patch. Some numbers measured on my x86-64: Before [13] .rodata PROGBITS 00000000000eaaa0 000eaaa0 0000000000008170 0000000000000000 A 0 0 32 [19] .data.rel.ro PROGBITS 00000000003045e0 001045e0 00000000000023d0 0000000000000000 WA 0 0 32 [23] .data PROGBITS 00000000003076e0 001076e0 0000000000004988 0000000000000000 WA 0 0 32 After [13] .rodata PROGBITS 00000000000eaaa0 000eaaa0 0000000000009a50 0000000000000000 A 0 0 32 [19] .data.rel.ro PROGBITS 0000000000306040 00106040 0000000000002608 0000000000000000 WA 0 0 32 [23] .data PROGBITS 0000000000309360 00109360 0000000000002e88 0000000000000000 WA 0 0 32 The size of the write-able data section decreased considerably. Some entries became const-after-relocation, while most of its content went straight into the read-only data section. Best regards, Thomas

.TH "SDL_Quit" "3" "Tue 11 Sep 2001, 23:00" "SDL" "SDL API Reference" 
.SH "NAME"
SDL_Quit \- Shut down SDL
.SH "SYNOPSIS"
.PP
\fB#include "SDL\&.h"
.sp
\fBvoid \fBSDL_Quit\fP\fR(\fBvoid\fR);
.SH "DESCRIPTION"
.PP
\fBSDL_Quit\fP shuts down all SDL subsystems and frees the resources allocated to them\&. This should always be called before you exit\&. For the sake of simplicity you can set \fBSDL_Quit\fP as your \fBatexit\fP call, like: 
.PP
.nf
\f(CWSDL_Init(SDL_INIT_VIDEO|SDL_INIT_AUDIO);
atexit(SDL_Quit);
\&.
\&.\fR
.fi
.PP
.PP
.RS
\fBNote:  
.PP
While using \fBatexit\fP maybe be fine for small programs, more advanced users should shut down SDL in their own cleanup code\&. Plus, using \fBatexit\fP in a library is a sure way to crash dynamically loaded code
.RE
.SH "SEE ALSO"
.PP
\fI\fBSDL_QuitSubsystem\fP\fR, \fI\fBSDL_Init\fP\fR
...\" created by instant / docbook-to-man, Tue 11 Sep 2001, 23:00