Mercurial > sdl-ios-xcode
view src/hermes/x86p_16.asm @ 4216:5b99971a27b4 SDL-1.2
Fixed bug #698
Hans de Goede 2009-02-13 01:10:52 PST
Since the new "glitch free" version of pulseaudio (used in Fedora 10 amongst
others), the sound of SDL using apps (like a simple playmus call) has been
crackling.
While looking in to fixing this I noticed that the current pulseaudio code in
SDL uses pa_simple. However pa_simple uses a thread to pump pulseaudio events
and ipc, given that SDL already has its own thread for audio handling this is
clearly suboptimal, leading to unnecessary context switching IPC, etc. Also
pa_simple does not allow one to implement the WaitAudio() callback for SDL
audiodrivers properly.
Given that my work is mostly a rewrite (although some original pieces remain)
I'm attaching the new .c and .h file, as that is easier to review then the huge
diff.
Let me know if you also want the diff.
This new version has the following features:
-no longer use an additional thread next to the SDL sound thread
-do not crackle with glitch free audio
-when used with a newer pulse, which does glitch free audio, the total latency
is
the same as with the alsa driver
-proper WaitAudio() implementation, saving another mixlen worth of latency
-adds a WaitDone() implementation
This patch has been written in consultancy with Lennart Poetering (the
pulseaudio author) and has been reviewed by him for correct use of the pa API.
author | Sam Lantinga <slouken@libsdl.org> |
---|---|
date | Mon, 21 Sep 2009 09:27:08 +0000 |
parents | 540466e900db |
children |
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line source
; ; x86 format converters for HERMES ; Copyright (c) 1998 Glenn Fielder (gaffer@gaffer.org) ; This source code is licensed under the GNU LGPL ; ; Please refer to the file COPYING.LIB contained in the distribution for ; licensing conditions ; ; Routines adjusted for Hermes by Christian Nentwich (brn@eleet.mcb.at) ; Used with permission. ; BITS 32 %include "common.inc" SDL_FUNC _ConvertX86p16_16BGR565 SDL_FUNC _ConvertX86p16_16RGB555 SDL_FUNC _ConvertX86p16_16BGR555 SDL_FUNC _ConvertX86p16_8RGB332 EXTERN _ConvertX86 SECTION .text _ConvertX86p16_16BGR565: ; check short cmp ecx,BYTE 16 ja .L3 .L1 ; short loop mov al,[esi] mov ah,[esi+1] mov ebx,eax mov edx,eax shr eax,11 and eax,BYTE 11111b and ebx,11111100000b shl edx,11 add eax,ebx add eax,edx mov [edi],al mov [edi+1],ah add esi,BYTE 2 add edi,BYTE 2 dec ecx jnz .L1 .L2 retn .L3 ; head mov eax,edi and eax,BYTE 11b jz .L4 mov al,[esi] mov ah,[esi+1] mov ebx,eax mov edx,eax shr eax,11 and eax,BYTE 11111b and ebx,11111100000b shl edx,11 add eax,ebx add eax,edx mov [edi],al mov [edi+1],ah add esi,BYTE 2 add edi,BYTE 2 dec ecx .L4 ; save count push ecx ; unroll twice shr ecx,1 ; point arrays to end lea esi,[esi+ecx*4] lea edi,[edi+ecx*4] ; negative counter neg ecx jmp SHORT .L6 .L5 mov [edi+ecx*4-4],eax .L6 mov eax,[esi+ecx*4] mov ebx,[esi+ecx*4] and eax,07E007E0h mov edx,[esi+ecx*4] and ebx,0F800F800h shr ebx,11 and edx,001F001Fh shl edx,11 add eax,ebx add eax,edx inc ecx jnz .L5 mov [edi+ecx*4-4],eax ; tail pop ecx and ecx,BYTE 1 jz .L7 mov al,[esi] mov ah,[esi+1] mov ebx,eax mov edx,eax shr eax,11 and eax,BYTE 11111b and ebx,11111100000b shl edx,11 add eax,ebx add eax,edx mov [edi],al mov [edi+1],ah add esi,BYTE 2 add edi,BYTE 2 .L7 retn _ConvertX86p16_16RGB555: ; check short cmp ecx,BYTE 32 ja .L3 .L1 ; short loop mov al,[esi] mov ah,[esi+1] mov ebx,eax shr ebx,1 and ebx, 0111111111100000b and eax,BYTE 0000000000011111b add eax,ebx mov [edi],al mov [edi+1],ah add esi,BYTE 2 add edi,BYTE 2 dec ecx jnz .L1 .L2 retn .L3 ; head mov eax,edi and eax,BYTE 11b jz .L4 mov al,[esi] mov ah,[esi+1] mov ebx,eax shr ebx,1 and ebx, 0111111111100000b and eax,BYTE 0000000000011111b add eax,ebx mov [edi],al mov [edi+1],ah add esi,BYTE 2 add edi,BYTE 2 dec ecx .L4 ; save ebp push ebp ; save count push ecx ; unroll four times shr ecx,2 ; point arrays to end lea esi,[esi+ecx*8] lea edi,[edi+ecx*8] ; negative counter xor ebp,ebp sub ebp,ecx .L5 mov eax,[esi+ebp*8] ; agi? mov ecx,[esi+ebp*8+4] mov ebx,eax mov edx,ecx and eax,0FFC0FFC0h and ecx,0FFC0FFC0h shr eax,1 and ebx,001F001Fh shr ecx,1 and edx,001F001Fh add eax,ebx add ecx,edx mov [edi+ebp*8],eax mov [edi+ebp*8+4],ecx inc ebp jnz .L5 ; tail pop ecx .L6 and ecx,BYTE 11b jz .L7 mov al,[esi] mov ah,[esi+1] mov ebx,eax shr ebx,1 and ebx, 0111111111100000b and eax,BYTE 0000000000011111b add eax,ebx mov [edi],al mov [edi+1],ah add esi,BYTE 2 add edi,BYTE 2 dec ecx jmp SHORT .L6 .L7 pop ebp retn _ConvertX86p16_16BGR555: ; check short cmp ecx,BYTE 16 ja .L3 .L1 ; short loop mov al,[esi] mov ah,[esi+1] mov ebx,eax mov edx,eax shr eax,11 and eax,BYTE 11111b shr ebx,1 and ebx,1111100000b shl edx,10 and edx,0111110000000000b add eax,ebx add eax,edx mov [edi],al mov [edi+1],ah add esi,BYTE 2 add edi,BYTE 2 dec ecx jnz .L1 .L2 retn .L3 ; head mov eax,edi and eax,BYTE 11b jz .L4 mov al,[esi] mov ah,[esi+1] mov ebx,eax mov edx,eax shr eax,11 and eax,BYTE 11111b shr ebx,1 and ebx,1111100000b shl edx,10 and edx,0111110000000000b add eax,ebx add eax,edx mov [edi],al mov [edi+1],ah add esi,BYTE 2 add edi,BYTE 2 dec ecx .L4 ; save count push ecx ; unroll twice shr ecx,1 ; point arrays to end lea esi,[esi+ecx*4] lea edi,[edi+ecx*4] ; negative counter neg ecx jmp SHORT .L6 .L5 mov [edi+ecx*4-4],eax .L6 mov eax,[esi+ecx*4] shr eax,1 mov ebx,[esi+ecx*4] and eax,03E003E0h mov edx,[esi+ecx*4] and ebx,0F800F800h shr ebx,11 and edx,001F001Fh shl edx,10 add eax,ebx add eax,edx inc ecx jnz .L5 mov [edi+ecx*4-4],eax ; tail pop ecx and ecx,BYTE 1 jz .L7 mov al,[esi] mov ah,[esi+1] mov ebx,eax mov edx,eax shr eax,11 and eax,BYTE 11111b shr ebx,1 and ebx,1111100000b shl edx,10 and edx,0111110000000000b add eax,ebx add eax,edx mov [edi],al mov [edi+1],ah add esi,BYTE 2 add edi,BYTE 2 .L7 retn _ConvertX86p16_8RGB332: ; check short cmp ecx,BYTE 16 ja .L3 .L1 ; short loop mov al,[esi+0] mov ah,[esi+1] mov ebx,eax mov edx,eax and eax,BYTE 11000b ; blue shr eax,3 and ebx,11100000000b ; green shr ebx,6 and edx,1110000000000000b ; red shr edx,8 add eax,ebx add eax,edx mov [edi],al add esi,BYTE 2 inc edi dec ecx jnz .L1 .L2 retn .L3 mov eax,edi and eax,BYTE 11b jz .L4 mov al,[esi+0] mov ah,[esi+1] mov ebx,eax mov edx,eax and eax,BYTE 11000b ; blue shr eax,3 and ebx,11100000000b ; green shr ebx,6 and edx,1110000000000000b ; red shr edx,8 add eax,ebx add eax,edx mov [edi],al add esi,BYTE 2 inc edi dec ecx jmp SHORT .L3 .L4 ; save ebp push ebp ; save count push ecx ; unroll 4 times shr ecx,2 ; prestep mov dl,[esi+0] mov bl,[esi+1] mov dh,[esi+2] .L5 shl edx,16 mov bh,[esi+3] shl ebx,16 mov dl,[esi+4] mov dh,[esi+6] mov bl,[esi+5] and edx,00011000000110000001100000011000b mov bh,[esi+7] ror edx,16+3 mov eax,ebx ; setup eax for reds and ebx,00000111000001110000011100000111b and eax,11100000111000001110000011100000b ; reds ror ebx,16-2 add esi,BYTE 8 ror eax,16 add edi,BYTE 4 add eax,ebx mov bl,[esi+1] ; greens add eax,edx mov dl,[esi+0] ; blues mov [edi-4],eax mov dh,[esi+2] dec ecx jnz .L5 ; check tail pop ecx and ecx,BYTE 11b jz .L7 .L6 ; tail mov al,[esi+0] mov ah,[esi+1] mov ebx,eax mov edx,eax and eax,BYTE 11000b ; blue shr eax,3 and ebx,11100000000b ; green shr ebx,6 and edx,1110000000000000b ; red shr edx,8 add eax,ebx add eax,edx mov [edi],al add esi,BYTE 2 inc edi dec ecx jnz .L6 .L7 pop ebp retn %ifidn __OUTPUT_FORMAT__,elf section .note.GNU-stack noalloc noexec nowrite progbits %endif