cbp_sse2.asm

视频压缩标准MPEG4的视频参考代码xvid9.1

;/**************************************************************************
; *
; *  XVID MPEG-4 VIDEO CODEC
; *  sse2 cbp calc
; *
; *  This file is part of XviD, a free MPEG-4 video encoder/decoder
; *
; *  XviD is free software; you can redistribute it and/or modify it
; *  under the terms of the GNU General Public License as published by
; *  the Free Software Foundation; either version 2 of the License, or
; *  (at your option) any later version.
; *
; *  This program 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 General Public License for more details.
; *
; *  You should have received a copy of the GNU General Public License
; *  along with this program; if not, write to the Free Software
; *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
; *
; *  Under section 8 of the GNU General Public License, the copyright
; *  holders of XVID explicitly forbid distribution in the following
; *  countries:
; *
; *    - Japan
; *    - United States of America
; *
; *  Linking XviD statically or dynamically with other modules is making a
; *  combined work based on XviD.  Thus, the terms and conditions of the
; *  GNU General Public License cover the whole combination.
; *
; *  As a special exception, the copyright holders of XviD give you
; *  permission to link XviD with independent modules that communicate with
; *  XviD solely through the VFW1.1 and DShow interfaces, regardless of the
; *  license terms of these independent modules, and to copy and distribute
; *  the resulting combined work under terms of your choice, provided that
; *  every copy of the combined work is accompanied by a complete copy of
; *  the source code of XviD (the version of XviD used to produce the
; *  combined work), being distributed under the terms of the GNU General
; *  Public License plus this exception.  An independent module is a module
; *  which is not derived from or based on XviD.
; *
; *  Note that people who make modified versions of XviD are not obligated
; *  to grant this special exception for their modified versions; it is
; *  their choice whether to do so.  The GNU General Public License gives
; *  permission to release a modified version without this exception; this
; *  exception also makes it possible to release a modified version which
; *  carries forward this exception.
; *
; * $Id: cbp_sse2.asm,v 1.2 2002/11/17 00:57:58 edgomez Exp $
; *
; *************************************************************************/

bits 32

section .data

%macro cglobal 1
	%ifdef PREFIX
		global _%1
		%define %1 _%1
	%else
		global %1
	%endif
%endmacro

align 16

ignore_dc	dw		0, -1, -1, -1, -1, -1, -1, -1

section .text

cglobal calc_cbp_sse2

;===========================================================================
;
; uint32_t calc_cbp_sse2(const int16_t coeff[6][64]);
;
; not enabled - slower than mmx?
;
;===========================================================================

%macro LOOP_SSE2 1
    movdqa	xmm0, [edx+(%1)*128]
	pand	xmm0, xmm7
	movdqa	xmm1, [edx+(%1)*128+16]

	por		xmm0, [edx+(%1)*128+32]
	por		xmm1, [edx+(%1)*128+48]
	por		xmm0, [edx+(%1)*128+64]
	por		xmm1, [edx+(%1)*128+80]
	por		xmm0, [edx+(%1)*128+96]
	por		xmm1, [edx+(%1)*128+112]

	por		xmm0, xmm1     ; xmm0 = xmm1 = 128 bits worth of info
	psadbw	xmm0, xmm6     ; contains 2 dwords with sums
	movhlps	xmm1, xmm0     ; move high dword from xmm0 to low xmm1
	por		xmm0, xmm1     ; combine
	movd	ecx, xmm0      ; if ecx set, values were found
	test    ecx, ecx
%endmacro

align 16

calc_cbp_sse2:
    mov     edx, [esp+4]        ; coeff[]
    xor		eax, eax		    ; cbp = 0

	movdqu	xmm7, [ignore_dc]	; mask to ignore dc value
	pxor	xmm6, xmm6          ; zero

  LOOP_SSE2 0
	test ecx, ecx	
	jz		.blk2
    or eax, (1<<5)
.blk2
  LOOP_SSE2 1
	test ecx, ecx	
	jz		.blk3
  or eax, (1<<4)
.blk3
  LOOP_SSE2 2
	test ecx, ecx	
	jz		.blk4
  or eax, (1<<3)
.blk4
  LOOP_SSE2 3
	test ecx, ecx	
	jz		.blk5
  or eax, (1<<2)
.blk5
  LOOP_SSE2 4
	test ecx, ecx	
	jz		.blk6
  or eax, (1<<1)
.blk6
  LOOP_SSE2 5
	test ecx, ecx	
	jz		.finished
  or eax, (1<<0)
.finished
				
  ret