Mercurial > sdl-ios-xcode
view src/audio/mint/SDL_mintaudio_dma8.h @ 1542:a8bf1aa21020
Fixed bug #15
SDL_blit_A.mmx-speed.patch.txt --
Speed improvements and a bugfix for the current GCC inline mmx
asm code:
- Changed some ops and removed some resulting useless ones.
- Added some instruction parallelism (some gain)
The resulting speed on my Xeon improved upto 35% depending on
the function (measured in fps).
- Fixed a bug where BlitRGBtoRGBSurfaceAlphaMMX() was
setting the alpha component on the destination surfaces (to
opaque-alpha) even when the surface had none.
SDL_blit_A.mmx-msvc.patch.txt --
MSVC mmx intrinsics version of the same GCC asm code.
MSVC compiler tries to parallelize the code and to avoid
register stalls, but does not always do a very good job.
Per-surface blending MSVC functions run quite a bit faster
than their pure-asm counterparts (upto 55% faster for 16bit
ones), but the per-pixel blending runs somewhat slower than asm.
- BlitRGBtoRGBSurfaceAlphaMMX and BlitRGBtoRGBPixelAlphaMMX (and all
variants) can now also handle formats other than (A)RGB8888. Formats
like RGBA8888 and some quite exotic ones are allowed -- like
RAGB8888, or actually anything having channels aligned on 8bit
boundary and full 8bit alpha (for per-pixel alpha blending).
The performance cost of this change is virtually 0 for per-surface
alpha blending (no extra ops inside the loop) and a single non-MMX
op inside the loop for per-pixel blending. In testing, the per-pixel
alpha blending takes a ~2% performance hit, but it still runs much
faster than the current code in CVS. If necessary, a separate function
with this functionality can be made.
This code requires Processor Pack for VC6.
author | Sam Lantinga <slouken@libsdl.org> |
---|---|
date | Wed, 15 Mar 2006 15:39:29 +0000 |
parents | d910939febfa |
children | 782fd950bd46 a1b03ba2fcd0 |
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/* SDL - Simple DirectMedia Layer Copyright (C) 1997-2004 Sam Lantinga This library is free software; you can redistribute it and/or modify it under the terms of the GNU Library General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. This library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Library General Public License for more details. You should have received a copy of the GNU Library General Public License along with this library; if not, write to the Free Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA Sam Lantinga slouken@libsdl.org */ #include "SDL_config.h" /* DMA 8bits and Falcon Codec audio definitions Patrice Mandin, Didier Méquignon */ #ifndef _SDL_mintaudio_dma8_h #define _SDL_mintaudio_dma8_h #define DMAAUDIO_IO_BASE (0xffff8900) struct DMAAUDIO_IO_S { unsigned char int_ctrl; unsigned char control; unsigned char dummy1; unsigned char start_high; unsigned char dummy2; unsigned char start_mid; unsigned char dummy3; unsigned char start_low; unsigned char dummy4; unsigned char cur_high; unsigned char dummy5; unsigned char cur_mid; unsigned char dummy6; unsigned char cur_low; unsigned char dummy7; unsigned char end_high; unsigned char dummy8; unsigned char end_mid; unsigned char dummy9; unsigned char end_low; unsigned char dummy10[12]; unsigned char track_ctrl; /* CODEC only */ unsigned char sound_ctrl; unsigned short sound_data; unsigned short sound_mask; unsigned char dummy11[10]; unsigned short dev_ctrl; unsigned short dest_ctrl; unsigned short sync_div; unsigned char track_rec; unsigned char adderin_input; unsigned char channel_input; unsigned char channel_amplification; unsigned char channel_reduction; unsigned char dummy12[6]; unsigned char data_direction; unsigned char dummy13; unsigned char dev_data; }; #define DMAAUDIO_IO ((*(volatile struct DMAAUDIO_IO_S *)DMAAUDIO_IO_BASE)) #endif /* _SDL_mintaudio_dma8_h */