aboutsummaryrefslogtreecommitdiff
path: root/simd/jimmxfst.asm
diff options
context:
space:
mode:
Diffstat (limited to 'simd/jimmxfst.asm')
-rw-r--r--simd/jimmxfst.asm500
1 files changed, 500 insertions, 0 deletions
diff --git a/simd/jimmxfst.asm b/simd/jimmxfst.asm
new file mode 100644
index 0000000..3b05572
--- /dev/null
+++ b/simd/jimmxfst.asm
@@ -0,0 +1,500 @@
+;
+; jimmxfst.asm - fast integer IDCT (MMX)
+;
+; Copyright 2009 Pierre Ossman <ossman@cendio.se> for Cendio AB
+;
+; Based on
+; x86 SIMD extension for IJG JPEG library
+; Copyright (C) 1999-2006, MIYASAKA Masaru.
+; For conditions of distribution and use, see copyright notice in jsimdext.inc
+;
+; This file should be assembled with NASM (Netwide Assembler),
+; can *not* be assembled with Microsoft's MASM or any compatible
+; assembler (including Borland's Turbo Assembler).
+; NASM is available from http://nasm.sourceforge.net/ or
+; http://sourceforge.net/project/showfiles.php?group_id=6208
+;
+; This file contains a fast, not so accurate integer implementation of
+; the inverse DCT (Discrete Cosine Transform). The following code is
+; based directly on the IJG's original jidctfst.c; see the jidctfst.c
+; for more details.
+;
+; [TAB8]
+
+%include "jsimdext.inc"
+%include "jdct.inc"
+
+; --------------------------------------------------------------------------
+
+%define CONST_BITS 8 ; 14 is also OK.
+%define PASS1_BITS 2
+
+%if IFAST_SCALE_BITS != PASS1_BITS
+%error "'IFAST_SCALE_BITS' must be equal to 'PASS1_BITS'."
+%endif
+
+%if CONST_BITS == 8
+F_1_082 equ 277 ; FIX(1.082392200)
+F_1_414 equ 362 ; FIX(1.414213562)
+F_1_847 equ 473 ; FIX(1.847759065)
+F_2_613 equ 669 ; FIX(2.613125930)
+F_1_613 equ (F_2_613 - 256) ; FIX(2.613125930) - FIX(1)
+%else
+; NASM cannot do compile-time arithmetic on floating-point constants.
+%define DESCALE(x,n) (((x)+(1<<((n)-1)))>>(n))
+F_1_082 equ DESCALE(1162209775,30-CONST_BITS) ; FIX(1.082392200)
+F_1_414 equ DESCALE(1518500249,30-CONST_BITS) ; FIX(1.414213562)
+F_1_847 equ DESCALE(1984016188,30-CONST_BITS) ; FIX(1.847759065)
+F_2_613 equ DESCALE(2805822602,30-CONST_BITS) ; FIX(2.613125930)
+F_1_613 equ (F_2_613 - (1 << CONST_BITS)) ; FIX(2.613125930) - FIX(1)
+%endif
+
+; --------------------------------------------------------------------------
+ SECTION SEG_CONST
+
+; PRE_MULTIPLY_SCALE_BITS <= 2 (to avoid overflow)
+; CONST_BITS + CONST_SHIFT + PRE_MULTIPLY_SCALE_BITS == 16 (for pmulhw)
+
+%define PRE_MULTIPLY_SCALE_BITS 2
+%define CONST_SHIFT (16 - PRE_MULTIPLY_SCALE_BITS - CONST_BITS)
+
+ alignz 16
+ global EXTN(jconst_idct_ifast_mmx)
+
+EXTN(jconst_idct_ifast_mmx):
+
+PW_F1414 times 4 dw F_1_414 << CONST_SHIFT
+PW_F1847 times 4 dw F_1_847 << CONST_SHIFT
+PW_MF1613 times 4 dw -F_1_613 << CONST_SHIFT
+PW_F1082 times 4 dw F_1_082 << CONST_SHIFT
+PB_CENTERJSAMP times 8 db CENTERJSAMPLE
+
+ alignz 16
+
+; --------------------------------------------------------------------------
+ SECTION SEG_TEXT
+ BITS 32
+;
+; Perform dequantization and inverse DCT on one block of coefficients.
+;
+; GLOBAL(void)
+; jsimd_idct_ifast_mmx (void * dct_table, JCOEFPTR coef_block,
+; JSAMPARRAY output_buf, JDIMENSION output_col)
+;
+
+%define dct_table(b) (b)+8 ; jpeg_component_info * compptr
+%define coef_block(b) (b)+12 ; JCOEFPTR coef_block
+%define output_buf(b) (b)+16 ; JSAMPARRAY output_buf
+%define output_col(b) (b)+20 ; JDIMENSION output_col
+
+%define original_ebp ebp+0
+%define wk(i) ebp-(WK_NUM-(i))*SIZEOF_MMWORD ; mmword wk[WK_NUM]
+%define WK_NUM 2
+%define workspace wk(0)-DCTSIZE2*SIZEOF_JCOEF
+ ; JCOEF workspace[DCTSIZE2]
+
+ align 16
+ global EXTN(jsimd_idct_ifast_mmx)
+
+EXTN(jsimd_idct_ifast_mmx):
+ push ebp
+ mov eax,esp ; eax = original ebp
+ sub esp, byte 4
+ and esp, byte (-SIZEOF_MMWORD) ; align to 64 bits
+ mov [esp],eax
+ mov ebp,esp ; ebp = aligned ebp
+ lea esp, [workspace]
+ push ebx
+; push ecx ; need not be preserved
+; push edx ; need not be preserved
+ push esi
+ push edi
+
+ get_GOT ebx ; get GOT address
+
+ ; ---- Pass 1: process columns from input, store into work array.
+
+; mov eax, [original_ebp]
+ mov edx, POINTER [dct_table(eax)] ; quantptr
+ mov esi, JCOEFPTR [coef_block(eax)] ; inptr
+ lea edi, [workspace] ; JCOEF * wsptr
+ mov ecx, DCTSIZE/4 ; ctr
+ alignx 16,7
+.columnloop:
+%ifndef NO_ZERO_COLUMN_TEST_IFAST_MMX
+ mov eax, DWORD [DWBLOCK(1,0,esi,SIZEOF_JCOEF)]
+ or eax, DWORD [DWBLOCK(2,0,esi,SIZEOF_JCOEF)]
+ jnz short .columnDCT
+
+ movq mm0, MMWORD [MMBLOCK(1,0,esi,SIZEOF_JCOEF)]
+ movq mm1, MMWORD [MMBLOCK(2,0,esi,SIZEOF_JCOEF)]
+ por mm0, MMWORD [MMBLOCK(3,0,esi,SIZEOF_JCOEF)]
+ por mm1, MMWORD [MMBLOCK(4,0,esi,SIZEOF_JCOEF)]
+ por mm0, MMWORD [MMBLOCK(5,0,esi,SIZEOF_JCOEF)]
+ por mm1, MMWORD [MMBLOCK(6,0,esi,SIZEOF_JCOEF)]
+ por mm0, MMWORD [MMBLOCK(7,0,esi,SIZEOF_JCOEF)]
+ por mm1,mm0
+ packsswb mm1,mm1
+ movd eax,mm1
+ test eax,eax
+ jnz short .columnDCT
+
+ ; -- AC terms all zero
+
+ movq mm0, MMWORD [MMBLOCK(0,0,esi,SIZEOF_JCOEF)]
+ pmullw mm0, MMWORD [MMBLOCK(0,0,edx,SIZEOF_IFAST_MULT_TYPE)]
+
+ movq mm2,mm0 ; mm0=in0=(00 01 02 03)
+ punpcklwd mm0,mm0 ; mm0=(00 00 01 01)
+ punpckhwd mm2,mm2 ; mm2=(02 02 03 03)
+
+ movq mm1,mm0
+ punpckldq mm0,mm0 ; mm0=(00 00 00 00)
+ punpckhdq mm1,mm1 ; mm1=(01 01 01 01)
+ movq mm3,mm2
+ punpckldq mm2,mm2 ; mm2=(02 02 02 02)
+ punpckhdq mm3,mm3 ; mm3=(03 03 03 03)
+
+ movq MMWORD [MMBLOCK(0,0,edi,SIZEOF_JCOEF)], mm0
+ movq MMWORD [MMBLOCK(0,1,edi,SIZEOF_JCOEF)], mm0
+ movq MMWORD [MMBLOCK(1,0,edi,SIZEOF_JCOEF)], mm1
+ movq MMWORD [MMBLOCK(1,1,edi,SIZEOF_JCOEF)], mm1
+ movq MMWORD [MMBLOCK(2,0,edi,SIZEOF_JCOEF)], mm2
+ movq MMWORD [MMBLOCK(2,1,edi,SIZEOF_JCOEF)], mm2
+ movq MMWORD [MMBLOCK(3,0,edi,SIZEOF_JCOEF)], mm3
+ movq MMWORD [MMBLOCK(3,1,edi,SIZEOF_JCOEF)], mm3
+ jmp near .nextcolumn
+ alignx 16,7
+%endif
+.columnDCT:
+
+ ; -- Even part
+
+ movq mm0, MMWORD [MMBLOCK(0,0,esi,SIZEOF_JCOEF)]
+ movq mm1, MMWORD [MMBLOCK(2,0,esi,SIZEOF_JCOEF)]
+ pmullw mm0, MMWORD [MMBLOCK(0,0,edx,SIZEOF_IFAST_MULT_TYPE)]
+ pmullw mm1, MMWORD [MMBLOCK(2,0,edx,SIZEOF_IFAST_MULT_TYPE)]
+ movq mm2, MMWORD [MMBLOCK(4,0,esi,SIZEOF_JCOEF)]
+ movq mm3, MMWORD [MMBLOCK(6,0,esi,SIZEOF_JCOEF)]
+ pmullw mm2, MMWORD [MMBLOCK(4,0,edx,SIZEOF_IFAST_MULT_TYPE)]
+ pmullw mm3, MMWORD [MMBLOCK(6,0,edx,SIZEOF_IFAST_MULT_TYPE)]
+
+ movq mm4,mm0
+ movq mm5,mm1
+ psubw mm0,mm2 ; mm0=tmp11
+ psubw mm1,mm3
+ paddw mm4,mm2 ; mm4=tmp10
+ paddw mm5,mm3 ; mm5=tmp13
+
+ psllw mm1,PRE_MULTIPLY_SCALE_BITS
+ pmulhw mm1,[GOTOFF(ebx,PW_F1414)]
+ psubw mm1,mm5 ; mm1=tmp12
+
+ movq mm6,mm4
+ movq mm7,mm0
+ psubw mm4,mm5 ; mm4=tmp3
+ psubw mm0,mm1 ; mm0=tmp2
+ paddw mm6,mm5 ; mm6=tmp0
+ paddw mm7,mm1 ; mm7=tmp1
+
+ movq MMWORD [wk(1)], mm4 ; wk(1)=tmp3
+ movq MMWORD [wk(0)], mm0 ; wk(0)=tmp2
+
+ ; -- Odd part
+
+ movq mm2, MMWORD [MMBLOCK(1,0,esi,SIZEOF_JCOEF)]
+ movq mm3, MMWORD [MMBLOCK(3,0,esi,SIZEOF_JCOEF)]
+ pmullw mm2, MMWORD [MMBLOCK(1,0,edx,SIZEOF_IFAST_MULT_TYPE)]
+ pmullw mm3, MMWORD [MMBLOCK(3,0,edx,SIZEOF_IFAST_MULT_TYPE)]
+ movq mm5, MMWORD [MMBLOCK(5,0,esi,SIZEOF_JCOEF)]
+ movq mm1, MMWORD [MMBLOCK(7,0,esi,SIZEOF_JCOEF)]
+ pmullw mm5, MMWORD [MMBLOCK(5,0,edx,SIZEOF_IFAST_MULT_TYPE)]
+ pmullw mm1, MMWORD [MMBLOCK(7,0,edx,SIZEOF_IFAST_MULT_TYPE)]
+
+ movq mm4,mm2
+ movq mm0,mm5
+ psubw mm2,mm1 ; mm2=z12
+ psubw mm5,mm3 ; mm5=z10
+ paddw mm4,mm1 ; mm4=z11
+ paddw mm0,mm3 ; mm0=z13
+
+ movq mm1,mm5 ; mm1=z10(unscaled)
+ psllw mm2,PRE_MULTIPLY_SCALE_BITS
+ psllw mm5,PRE_MULTIPLY_SCALE_BITS
+
+ movq mm3,mm4
+ psubw mm4,mm0
+ paddw mm3,mm0 ; mm3=tmp7
+
+ psllw mm4,PRE_MULTIPLY_SCALE_BITS
+ pmulhw mm4,[GOTOFF(ebx,PW_F1414)] ; mm4=tmp11
+
+ ; To avoid overflow...
+ ;
+ ; (Original)
+ ; tmp12 = -2.613125930 * z10 + z5;
+ ;
+ ; (This implementation)
+ ; tmp12 = (-1.613125930 - 1) * z10 + z5;
+ ; = -1.613125930 * z10 - z10 + z5;
+
+ movq mm0,mm5
+ paddw mm5,mm2
+ pmulhw mm5,[GOTOFF(ebx,PW_F1847)] ; mm5=z5
+ pmulhw mm0,[GOTOFF(ebx,PW_MF1613)]
+ pmulhw mm2,[GOTOFF(ebx,PW_F1082)]
+ psubw mm0,mm1
+ psubw mm2,mm5 ; mm2=tmp10
+ paddw mm0,mm5 ; mm0=tmp12
+
+ ; -- Final output stage
+
+ psubw mm0,mm3 ; mm0=tmp6
+ movq mm1,mm6
+ movq mm5,mm7
+ paddw mm6,mm3 ; mm6=data0=(00 01 02 03)
+ paddw mm7,mm0 ; mm7=data1=(10 11 12 13)
+ psubw mm1,mm3 ; mm1=data7=(70 71 72 73)
+ psubw mm5,mm0 ; mm5=data6=(60 61 62 63)
+ psubw mm4,mm0 ; mm4=tmp5
+
+ movq mm3,mm6 ; transpose coefficients(phase 1)
+ punpcklwd mm6,mm7 ; mm6=(00 10 01 11)
+ punpckhwd mm3,mm7 ; mm3=(02 12 03 13)
+ movq mm0,mm5 ; transpose coefficients(phase 1)
+ punpcklwd mm5,mm1 ; mm5=(60 70 61 71)
+ punpckhwd mm0,mm1 ; mm0=(62 72 63 73)
+
+ movq mm7, MMWORD [wk(0)] ; mm7=tmp2
+ movq mm1, MMWORD [wk(1)] ; mm1=tmp3
+
+ movq MMWORD [wk(0)], mm5 ; wk(0)=(60 70 61 71)
+ movq MMWORD [wk(1)], mm0 ; wk(1)=(62 72 63 73)
+
+ paddw mm2,mm4 ; mm2=tmp4
+ movq mm5,mm7
+ movq mm0,mm1
+ paddw mm7,mm4 ; mm7=data2=(20 21 22 23)
+ paddw mm1,mm2 ; mm1=data4=(40 41 42 43)
+ psubw mm5,mm4 ; mm5=data5=(50 51 52 53)
+ psubw mm0,mm2 ; mm0=data3=(30 31 32 33)
+
+ movq mm4,mm7 ; transpose coefficients(phase 1)
+ punpcklwd mm7,mm0 ; mm7=(20 30 21 31)
+ punpckhwd mm4,mm0 ; mm4=(22 32 23 33)
+ movq mm2,mm1 ; transpose coefficients(phase 1)
+ punpcklwd mm1,mm5 ; mm1=(40 50 41 51)
+ punpckhwd mm2,mm5 ; mm2=(42 52 43 53)
+
+ movq mm0,mm6 ; transpose coefficients(phase 2)
+ punpckldq mm6,mm7 ; mm6=(00 10 20 30)
+ punpckhdq mm0,mm7 ; mm0=(01 11 21 31)
+ movq mm5,mm3 ; transpose coefficients(phase 2)
+ punpckldq mm3,mm4 ; mm3=(02 12 22 32)
+ punpckhdq mm5,mm4 ; mm5=(03 13 23 33)
+
+ movq mm7, MMWORD [wk(0)] ; mm7=(60 70 61 71)
+ movq mm4, MMWORD [wk(1)] ; mm4=(62 72 63 73)
+
+ movq MMWORD [MMBLOCK(0,0,edi,SIZEOF_JCOEF)], mm6
+ movq MMWORD [MMBLOCK(1,0,edi,SIZEOF_JCOEF)], mm0
+ movq MMWORD [MMBLOCK(2,0,edi,SIZEOF_JCOEF)], mm3
+ movq MMWORD [MMBLOCK(3,0,edi,SIZEOF_JCOEF)], mm5
+
+ movq mm6,mm1 ; transpose coefficients(phase 2)
+ punpckldq mm1,mm7 ; mm1=(40 50 60 70)
+ punpckhdq mm6,mm7 ; mm6=(41 51 61 71)
+ movq mm0,mm2 ; transpose coefficients(phase 2)
+ punpckldq mm2,mm4 ; mm2=(42 52 62 72)
+ punpckhdq mm0,mm4 ; mm0=(43 53 63 73)
+
+ movq MMWORD [MMBLOCK(0,1,edi,SIZEOF_JCOEF)], mm1
+ movq MMWORD [MMBLOCK(1,1,edi,SIZEOF_JCOEF)], mm6
+ movq MMWORD [MMBLOCK(2,1,edi,SIZEOF_JCOEF)], mm2
+ movq MMWORD [MMBLOCK(3,1,edi,SIZEOF_JCOEF)], mm0
+
+.nextcolumn:
+ add esi, byte 4*SIZEOF_JCOEF ; coef_block
+ add edx, byte 4*SIZEOF_IFAST_MULT_TYPE ; quantptr
+ add edi, byte 4*DCTSIZE*SIZEOF_JCOEF ; wsptr
+ dec ecx ; ctr
+ jnz near .columnloop
+
+ ; ---- Pass 2: process rows from work array, store into output array.
+
+ mov eax, [original_ebp]
+ lea esi, [workspace] ; JCOEF * wsptr
+ mov edi, JSAMPARRAY [output_buf(eax)] ; (JSAMPROW *)
+ mov eax, JDIMENSION [output_col(eax)]
+ mov ecx, DCTSIZE/4 ; ctr
+ alignx 16,7
+.rowloop:
+
+ ; -- Even part
+
+ movq mm0, MMWORD [MMBLOCK(0,0,esi,SIZEOF_JCOEF)]
+ movq mm1, MMWORD [MMBLOCK(2,0,esi,SIZEOF_JCOEF)]
+ movq mm2, MMWORD [MMBLOCK(4,0,esi,SIZEOF_JCOEF)]
+ movq mm3, MMWORD [MMBLOCK(6,0,esi,SIZEOF_JCOEF)]
+
+ movq mm4,mm0
+ movq mm5,mm1
+ psubw mm0,mm2 ; mm0=tmp11
+ psubw mm1,mm3
+ paddw mm4,mm2 ; mm4=tmp10
+ paddw mm5,mm3 ; mm5=tmp13
+
+ psllw mm1,PRE_MULTIPLY_SCALE_BITS
+ pmulhw mm1,[GOTOFF(ebx,PW_F1414)]
+ psubw mm1,mm5 ; mm1=tmp12
+
+ movq mm6,mm4
+ movq mm7,mm0
+ psubw mm4,mm5 ; mm4=tmp3
+ psubw mm0,mm1 ; mm0=tmp2
+ paddw mm6,mm5 ; mm6=tmp0
+ paddw mm7,mm1 ; mm7=tmp1
+
+ movq MMWORD [wk(1)], mm4 ; wk(1)=tmp3
+ movq MMWORD [wk(0)], mm0 ; wk(0)=tmp2
+
+ ; -- Odd part
+
+ movq mm2, MMWORD [MMBLOCK(1,0,esi,SIZEOF_JCOEF)]
+ movq mm3, MMWORD [MMBLOCK(3,0,esi,SIZEOF_JCOEF)]
+ movq mm5, MMWORD [MMBLOCK(5,0,esi,SIZEOF_JCOEF)]
+ movq mm1, MMWORD [MMBLOCK(7,0,esi,SIZEOF_JCOEF)]
+
+ movq mm4,mm2
+ movq mm0,mm5
+ psubw mm2,mm1 ; mm2=z12
+ psubw mm5,mm3 ; mm5=z10
+ paddw mm4,mm1 ; mm4=z11
+ paddw mm0,mm3 ; mm0=z13
+
+ movq mm1,mm5 ; mm1=z10(unscaled)
+ psllw mm2,PRE_MULTIPLY_SCALE_BITS
+ psllw mm5,PRE_MULTIPLY_SCALE_BITS
+
+ movq mm3,mm4
+ psubw mm4,mm0
+ paddw mm3,mm0 ; mm3=tmp7
+
+ psllw mm4,PRE_MULTIPLY_SCALE_BITS
+ pmulhw mm4,[GOTOFF(ebx,PW_F1414)] ; mm4=tmp11
+
+ ; To avoid overflow...
+ ;
+ ; (Original)
+ ; tmp12 = -2.613125930 * z10 + z5;
+ ;
+ ; (This implementation)
+ ; tmp12 = (-1.613125930 - 1) * z10 + z5;
+ ; = -1.613125930 * z10 - z10 + z5;
+
+ movq mm0,mm5
+ paddw mm5,mm2
+ pmulhw mm5,[GOTOFF(ebx,PW_F1847)] ; mm5=z5
+ pmulhw mm0,[GOTOFF(ebx,PW_MF1613)]
+ pmulhw mm2,[GOTOFF(ebx,PW_F1082)]
+ psubw mm0,mm1
+ psubw mm2,mm5 ; mm2=tmp10
+ paddw mm0,mm5 ; mm0=tmp12
+
+ ; -- Final output stage
+
+ psubw mm0,mm3 ; mm0=tmp6
+ movq mm1,mm6
+ movq mm5,mm7
+ paddw mm6,mm3 ; mm6=data0=(00 10 20 30)
+ paddw mm7,mm0 ; mm7=data1=(01 11 21 31)
+ psraw mm6,(PASS1_BITS+3) ; descale
+ psraw mm7,(PASS1_BITS+3) ; descale
+ psubw mm1,mm3 ; mm1=data7=(07 17 27 37)
+ psubw mm5,mm0 ; mm5=data6=(06 16 26 36)
+ psraw mm1,(PASS1_BITS+3) ; descale
+ psraw mm5,(PASS1_BITS+3) ; descale
+ psubw mm4,mm0 ; mm4=tmp5
+
+ packsswb mm6,mm5 ; mm6=(00 10 20 30 06 16 26 36)
+ packsswb mm7,mm1 ; mm7=(01 11 21 31 07 17 27 37)
+
+ movq mm3, MMWORD [wk(0)] ; mm3=tmp2
+ movq mm0, MMWORD [wk(1)] ; mm0=tmp3
+
+ paddw mm2,mm4 ; mm2=tmp4
+ movq mm5,mm3
+ movq mm1,mm0
+ paddw mm3,mm4 ; mm3=data2=(02 12 22 32)
+ paddw mm0,mm2 ; mm0=data4=(04 14 24 34)
+ psraw mm3,(PASS1_BITS+3) ; descale
+ psraw mm0,(PASS1_BITS+3) ; descale
+ psubw mm5,mm4 ; mm5=data5=(05 15 25 35)
+ psubw mm1,mm2 ; mm1=data3=(03 13 23 33)
+ psraw mm5,(PASS1_BITS+3) ; descale
+ psraw mm1,(PASS1_BITS+3) ; descale
+
+ movq mm4,[GOTOFF(ebx,PB_CENTERJSAMP)] ; mm4=[PB_CENTERJSAMP]
+
+ packsswb mm3,mm0 ; mm3=(02 12 22 32 04 14 24 34)
+ packsswb mm1,mm5 ; mm1=(03 13 23 33 05 15 25 35)
+
+ paddb mm6,mm4
+ paddb mm7,mm4
+ paddb mm3,mm4
+ paddb mm1,mm4
+
+ movq mm2,mm6 ; transpose coefficients(phase 1)
+ punpcklbw mm6,mm7 ; mm6=(00 01 10 11 20 21 30 31)
+ punpckhbw mm2,mm7 ; mm2=(06 07 16 17 26 27 36 37)
+ movq mm0,mm3 ; transpose coefficients(phase 1)
+ punpcklbw mm3,mm1 ; mm3=(02 03 12 13 22 23 32 33)
+ punpckhbw mm0,mm1 ; mm0=(04 05 14 15 24 25 34 35)
+
+ movq mm5,mm6 ; transpose coefficients(phase 2)
+ punpcklwd mm6,mm3 ; mm6=(00 01 02 03 10 11 12 13)
+ punpckhwd mm5,mm3 ; mm5=(20 21 22 23 30 31 32 33)
+ movq mm4,mm0 ; transpose coefficients(phase 2)
+ punpcklwd mm0,mm2 ; mm0=(04 05 06 07 14 15 16 17)
+ punpckhwd mm4,mm2 ; mm4=(24 25 26 27 34 35 36 37)
+
+ movq mm7,mm6 ; transpose coefficients(phase 3)
+ punpckldq mm6,mm0 ; mm6=(00 01 02 03 04 05 06 07)
+ punpckhdq mm7,mm0 ; mm7=(10 11 12 13 14 15 16 17)
+ movq mm1,mm5 ; transpose coefficients(phase 3)
+ punpckldq mm5,mm4 ; mm5=(20 21 22 23 24 25 26 27)
+ punpckhdq mm1,mm4 ; mm1=(30 31 32 33 34 35 36 37)
+
+ pushpic ebx ; save GOT address
+
+ mov edx, JSAMPROW [edi+0*SIZEOF_JSAMPROW]
+ mov ebx, JSAMPROW [edi+1*SIZEOF_JSAMPROW]
+ movq MMWORD [edx+eax*SIZEOF_JSAMPLE], mm6
+ movq MMWORD [ebx+eax*SIZEOF_JSAMPLE], mm7
+ mov edx, JSAMPROW [edi+2*SIZEOF_JSAMPROW]
+ mov ebx, JSAMPROW [edi+3*SIZEOF_JSAMPROW]
+ movq MMWORD [edx+eax*SIZEOF_JSAMPLE], mm5
+ movq MMWORD [ebx+eax*SIZEOF_JSAMPLE], mm1
+
+ poppic ebx ; restore GOT address
+
+ add esi, byte 4*SIZEOF_JCOEF ; wsptr
+ add edi, byte 4*SIZEOF_JSAMPROW
+ dec ecx ; ctr
+ jnz near .rowloop
+
+ emms ; empty MMX state
+
+ pop edi
+ pop esi
+; pop edx ; need not be preserved
+; pop ecx ; need not be preserved
+ pop ebx
+ mov esp,ebp ; esp <- aligned ebp
+ pop esp ; esp <- original ebp
+ pop ebp
+ ret
+
+; For some reason, the OS X linker does not honor the request to align the
+; segment unless we do this.
+ align 16