fdct_sse2_skal.asm

这是一个Xvid的源代码

  movdqa xmm3, [sqrt2]
  movdqa xmm7, xmm4
  movdqa xmm6, xmm2
  psubsw xmm4, xmm1       ; tp17-tp35 = t1
  psubsw xmm2, xmm0       ; tm17-tm35 = b3
  paddsw xmm1, xmm7       ; tp17+tp35 = b0
  paddsw xmm0, xmm6       ; tm17+tm35 = t2

    ; xmm1 = b0, xmm2 = b3. preserved

  movdqa xmm6, xmm4
  psubsw xmm4, xmm0       ; t1-t2
  paddsw xmm0, xmm6       ; t1+t2

  pmulhw xmm4, xmm3       ; (t1-t2)/(2.sqrt2)
  pmulhw xmm0, xmm3       ; (t1+t2)/(2.sqrt2)

  paddsw xmm0, xmm0       ; 2.(t1+t2) = b1
  paddsw xmm4, xmm4       ; 2.(t1-t2) = b2

  movdqa xmm7, [tan2]    ; t2
  movdqa xmm3, [%1+2*16] ; x2
  movdqa xmm6, [%1+6*16] ; x6
  movdqa xmm5, xmm7       ; t2

  pmulhw xmm7, xmm6       ; x6*t2
  pmulhw xmm5, xmm3       ; x2*t2

  paddsw xmm7, xmm3       ; x2+x6*t2 = tp26
  psubsw xmm5, xmm6       ; x2*t2-x6 = tm26


  ; use:xmm3,xmm5,xmm6,xmm7   frozen: xmm0,xmm4,xmm1,xmm2

  movdqa xmm3, [%1+0*16] ; x0
  movdqa xmm6, [%1+4*16] ; x4

  psubsw xmm3, xmm6   ; x0-x4 = tm04
  paddsw xmm6, xmm6   ; 2.x4
  paddsw xmm6, xmm3   ; x0+x4 = tp04

  psubsw xmm3, xmm5   ; tm04-tm26 = a2
  psubsw xmm6, xmm7   ; tp04-tp26 = a3
  paddsw xmm5, xmm5   ; 2.tm26
  paddsw xmm7, xmm7   ; 2.tp26
  paddsw xmm5, xmm3   ; tm04+tm26 = a1
  paddsw xmm7, xmm6   ; tp04+tp26 = a0

  psubsw xmm5, xmm0   ; a1-b1
  psubsw xmm3, xmm4   ; a2-b2
  paddsw xmm0, xmm0   ; 2.b1
  paddsw xmm4, xmm4   ; 2.b2
  paddsw xmm0, xmm5   ; a1+b1
  paddsw xmm4, xmm3   ; a2+b2

  psraw  xmm5, 6     ; out6
  psraw  xmm3, 6     ; out5
  psraw  xmm0, 6     ; out1
  psraw  xmm4, 6     ; out2

  movdqa [%1+6*16], xmm5
  movdqa [%1+5*16], xmm3
  movdqa [%1+1*16], xmm0
  movdqa [%1+2*16], xmm4

    ; reminder: xmm1=b0, xmm2=b3, xmm7=a0, xmm6=a3

  movdqa xmm0, xmm7
  movdqa xmm4, xmm6
  psubsw xmm7, xmm1   ; a0-b0
  psubsw xmm6, xmm2   ; a3-b3
  paddsw xmm1, xmm0   ; a0+b0
  paddsw xmm2, xmm4   ; a3+b3

  psraw  xmm1, 6     ; out0
  psraw  xmm7, 6     ; out7
  psraw  xmm2, 6     ; out3
  psraw  xmm6, 6     ; out4

  movdqa [%1+0*16], xmm1
  movdqa [%1+3*16], xmm2
  movdqa [%1+4*16], xmm6
  movdqa [%1+7*16], xmm7
%endmacro

;-----------------------------------------------------------------------------
; Function idct (the straight forward version)
;-----------------------------------------------------------------------------

ALIGN 16
idct_sse2_skal:
  mov ecx, [esp+4]
  iMTX_MULT  0, iTab1, Idct_Rnd0, 11
  iMTX_MULT  1, iTab2, Idct_Rnd1, 11
  iMTX_MULT  2, iTab3, Idct_Rnd2, 11
  iMTX_MULT  3, iTab4, Idct_Rnd3, 11
  iMTX_MULT  4, iTab1, Idct_Rnd4, 11
  iMTX_MULT  5, iTab4, Idct_Rnd5, 11
  iMTX_MULT  6, iTab3, Idct_Rnd6, 11
  iMTX_MULT  7, iTab2, Idct_Rnd7, 11
  iLLM_PASS ecx+0
  ret

;-----------------------------------------------------------------------------
; Helper macro TEST_ROW (test a null row)
;-----------------------------------------------------------------------------

%macro TEST_ROW 2     ; %1:src,  %2:label x8
  mov eax, [%1   ]
  mov edx, [%1+ 8]
  or  eax, [%1+ 4]
  or  edx, [%1+12]
  or  eax, edx
  jz near %2
%endmacro

;-----------------------------------------------------------------------------
; Function idct (this one skips null rows)
;-----------------------------------------------------------------------------

ALIGN 16
idct_sse2_sparse_skal:

  mov ecx, [esp+ 4]  ; Src

  TEST_ROW ecx, .Row0_Round
  iMTX_MULT  0, iTab1, Idct_Rnd0, 11
  jmp .Row1
.Row0_Round
  movq mm0, [Idct_Sparse_Rnd0]
  movq [ecx  ], mm0
  movq [ecx+8], mm0

.Row1
  TEST_ROW ecx+16, .Row1_Round
  iMTX_MULT  1, iTab2, Idct_Rnd1, 11
  jmp .Row2
.Row1_Round
  movq mm0, [Idct_Sparse_Rnd1]
  movq [ecx+16  ], mm0
  movq [ecx+16+8], mm0

.Row2
  TEST_ROW ecx+32, .Row2_Round
  iMTX_MULT  2, iTab3, Idct_Rnd2, 11
  jmp .Row3
.Row2_Round
  movq mm0, [Idct_Sparse_Rnd2]
  movq [ecx+32  ], mm0
  movq [ecx+32+8], mm0

.Row3
  TEST_ROW ecx+48, .Row4
  iMTX_MULT  3, iTab4, Idct_Rnd3, 11
  jmp .Row4

.Row4
  TEST_ROW ecx+64, .Row5
  iMTX_MULT  4, iTab1, Idct_Rnd4, 11
  jmp .Row5

.Row5
  TEST_ROW ecx+80, .Row6
  iMTX_MULT  5, iTab4, Idct_Rnd5, 11

.Row6
  TEST_ROW ecx+96, .Row7
  iMTX_MULT  6, iTab3, Idct_Rnd6, 11

.Row7
  TEST_ROW ecx+112, .End
  iMTX_MULT  7, iTab2, Idct_Rnd7, 11
.End

  iLLM_PASS ecx+0
  ret

;-----------------------------------------------------------------------------
; Helper macro fLLM_PASS
;-----------------------------------------------------------------------------

%macro fLLM_PASS 2  ; %1: src/dst, %2:Shift

  movdqa xmm0, [%1+0*16]   ; In0
  movdqa xmm2, [%1+2*16]   ; In2
  movdqa xmm3, xmm0
  movdqa xmm4, xmm2
  movdqa xmm7, [%1+7*16]   ; In7
  movdqa xmm5, [%1+5*16]   ; In5

  psubsw xmm0, xmm7         ; t7 = In0-In7
  paddsw xmm7, xmm3         ; t0 = In0+In7
  psubsw xmm2, xmm5         ; t5 = In2-In5
  paddsw xmm5, xmm4         ; t2 = In2+In5

  movdqa xmm3, [%1+3*16]   ; In3
  movdqa xmm4, [%1+4*16]   ; In4
  movdqa xmm1, xmm3
  psubsw xmm3, xmm4         ; t4 = In3-In4
  paddsw xmm4, xmm1         ; t3 = In3+In4
  movdqa xmm6, [%1+6*16]   ; In6
  movdqa xmm1, [%1+1*16]   ; In1
  psubsw xmm1, xmm6         ; t6 = In1-In6
  paddsw xmm6, [%1+1*16]   ; t1 = In1+In6

  psubsw xmm7, xmm4         ; tm03 = t0-t3
  psubsw xmm6, xmm5         ; tm12 = t1-t2
  paddsw xmm4, xmm4         ; 2.t3
  paddsw xmm5, xmm5         ; 2.t2
  paddsw xmm4, xmm7         ; tp03 = t0+t3
  paddsw xmm5, xmm6         ; tp12 = t1+t2

  psllw  xmm2, %2+1        ; shift t5 (shift +1 to..
  psllw  xmm1, %2+1        ; shift t6  ..compensate cos4/2)
  psllw  xmm4, %2          ; shift t3
  psllw  xmm5, %2          ; shift t2
  psllw  xmm7, %2          ; shift t0
  psllw  xmm6, %2          ; shift t1
  psllw  xmm3, %2          ; shift t4
  psllw  xmm0, %2          ; shift t7

  psubsw xmm4, xmm5         ; out4 = tp03-tp12
  psubsw xmm1, xmm2         ; xmm1: t6-t5
  paddsw xmm5, xmm5
  paddsw xmm2, xmm2
  paddsw xmm5, xmm4         ; out0 = tp03+tp12
  movdqa [%1+4*16], xmm4   ; => out4
  paddsw xmm2, xmm1         ; xmm2: t6+t5
  movdqa [%1+0*16], xmm5   ; => out0

  movdqa xmm4, [tan2]      ; xmm4 <= tan2
  pmulhw xmm4, xmm7         ; tm03*tan2
  movdqa xmm5, [tan2]      ; xmm5 <= tan2
  psubsw xmm4, xmm6         ; out6 = tm03*tan2 - tm12
  pmulhw xmm5, xmm6         ; tm12*tan2
  paddsw xmm5, xmm7         ; out2 = tm12*tan2 + tm03

  movdqa xmm6, [sqrt2]  
  movdqa xmm7, [Rounder1]

  pmulhw xmm2, xmm6         ; xmm2: tp65 = (t6 + t5)*cos4
  por    xmm5, xmm7         ; correct out2
  por    xmm4, xmm7         ; correct out6
  pmulhw xmm1, xmm6         ; xmm1: tm65 = (t6 - t5)*cos4
  por    xmm2, xmm7         ; correct tp65

  movdqa [%1+2*16], xmm5   ; => out2
  movdqa xmm5, xmm3         ; save t4
  movdqa [%1+6*16], xmm4   ; => out6
  movdqa xmm4, xmm0         ; save t7
  
  psubsw xmm3, xmm1         ; xmm3: tm465 = t4 - tm65
  psubsw xmm0, xmm2         ; xmm0: tm765 = t7 - tp65
  paddsw xmm2, xmm4         ; xmm2: tp765 = t7 + tp65
  paddsw xmm1, xmm5         ; xmm1: tp465 = t4 + tm65

  movdqa xmm4, [tan3]      ; tan3 - 1
  movdqa xmm5, [tan1]      ; tan1

  movdqa xmm7, xmm3         ; save tm465
  pmulhw xmm3, xmm4         ; tm465*(tan3-1)
  movdqa xmm6, xmm1         ; save tp465
  pmulhw xmm1, xmm5         ; tp465*tan1

  paddsw xmm3, xmm7         ; tm465*tan3
  pmulhw xmm4, xmm0         ; tm765*(tan3-1)
  paddsw xmm4, xmm0         ; tm765*tan3
  pmulhw xmm5, xmm2         ; tp765*tan1

  paddsw xmm1, xmm2         ; out1 = tp765 + tp465*tan1
  psubsw xmm0, xmm3         ; out3 = tm765 - tm465*tan3
  paddsw xmm7, xmm4         ; out5 = tm465 + tm765*tan3
  psubsw xmm5, xmm6         ; out7 =-tp465 + tp765*tan1

  movdqa [%1+1*16], xmm1   ; => out1
  movdqa [%1+3*16], xmm0   ; => out3
  movdqa [%1+5*16], xmm7   ; => out5
  movdqa [%1+7*16], xmm5   ; => out7

%endmacro

;-----------------------------------------------------------------------------
;Helper macro fMTX_MULT
;-----------------------------------------------------------------------------

%macro fMTX_MULT 3   ; %1=src, %2 = Coeffs, %3=rounders

  movdqa   xmm0, [ecx+%1*16+0]   ; xmm0 = [0123][4567]
  pshufhw  xmm1, xmm0, 00011011b ; xmm1 = [----][7654]
  pshufd   xmm0, xmm0, 01000100b
  pshufd   xmm1, xmm1, 11101110b

  movdqa   xmm2, xmm0
  paddsw  xmm0, xmm1              ; xmm0 = [a0 a1 a2 a3]
  psubsw  xmm2, xmm1              ; xmm2 = [b0 b1 b2 b3]

  punpckldq xmm0, xmm2            ; xmm0 = [a0 a1 b0 b1][a2 a3 b2 b3]
  pshufd    xmm2, xmm0, 01001110b ; xmm2 = [a2 a3 b2 b3][a0 a1 b0 b1]

    ;  [M00 M01    M16 M17] [M06 M07    M22 M23]  x mm0 = [0 /1 /2'/3']
    ;  [M02 M03    M18 M19] [M04 M05    M20 M21]  x mm2 = [0'/1'/2 /3 ]
    ;  [M08 M09    M24 M25] [M14 M15    M30 M31]  x mm0 = [4 /5 /6'/7']
    ;  [M10 M11    M26 M27] [M12 M13    M28 M29]  x mm2 = [4'/5'/6 /7 ]

  movdqa  xmm1, [%2+16]
  movdqa  xmm3, [%2+32]
  pmaddwd xmm1, xmm2
  pmaddwd xmm3, xmm0
  pmaddwd xmm2, [%2+48]
  pmaddwd xmm0, [%2+ 0]

  paddd   xmm0, xmm1             ;  [ out0 | out1 ][ out2 | out3 ]
  paddd   xmm2, xmm3             ;  [ out4 | out5 ][ out6 | out7 ]
  psrad   xmm0, 16
  psrad   xmm2, 16
  
  packssdw xmm0, xmm2            ;  [ out0 .. out7 ]
  paddsw   xmm0, [%3]            ;  Round

  psraw    xmm0, 4               ; => [-2048, 2047]

  movdqa  [ecx+%1*16+0], xmm0
%endmacro

;-----------------------------------------------------------------------------
; Function Forward DCT
;-----------------------------------------------------------------------------

ALIGN 16
fdct_sse2_skal:
  mov ecx, [esp+4]
  fLLM_PASS ecx+0, 3
  fMTX_MULT  0, fTab1, Fdct_Rnd0
  fMTX_MULT  1, fTab2, Fdct_Rnd2
  fMTX_MULT  2, fTab3, Fdct_Rnd1
  fMTX_MULT  3, fTab4, Fdct_Rnd1
  fMTX_MULT  4, fTab1, Fdct_Rnd0
  fMTX_MULT  5, fTab4, Fdct_Rnd1
  fMTX_MULT  6, fTab3, Fdct_Rnd1
  fMTX_MULT  7, fTab2, Fdct_Rnd1
  ret