VDBPSADBW - Double Block Packed Sum-Absolute-Differences (SAD) on Unsigned Bytes

Opcode/ Instruction

Op / En

64/32 bit Mode Support

CPUID Feature Flag

Description

EVEX.128.66.0F3A.W0 42 /r ib VDBPSADBW xmm1 {k1}{z}, xmm2, xmm3/m128, imm8

A

V/V

AVX512VL AVX512BW

Compute packed SAD word results of unsigned bytes in dword block from xmm2 with unsigned bytes of dword blocks transformed from xmm3/m128 using the shuffle controls in imm8. Results are written to xmm1 under the writemask k1.

EVEX.256.66.0F3A.W0 42 /r ib VDBPSADBW ymm1 {k1}{z}, ymm2, ymm3/m256, imm8

A

V/V

AVX512VL AVX512BW

Compute packed SAD word results of unsigned bytes in dword block from ymm2 with unsigned bytes of dword blocks transformed from ymm3/m256 using the shuffle controls in imm8. Results are written to ymm1 under the writemask k1.

EVEX.512.66.0F3A.W0 42 /r ib VDBPSADBW zmm1 {k1}{z}, zmm2, zmm3/m512, imm8

A

V/V

AVX512BW

Compute packed SAD word results of unsigned bytes in dword block from zmm2 with unsigned bytes of dword blocks transformed from zmm3/m512 using the shuffle controls in imm8. Results are written to zmm1 under the writemask k1.

Instruction Operand Encoding

Op/En

Tuple Type

Operand 1

Operand 2

Operand 3

Operand 4

A

Full Mem

ModRM:reg (w)

EVEX.vvvv (r)

ModRM:r/m (r)

imm8

Description

Compute packed SAD (sum of absolute differences) word results of unsigned bytes from two 32-bit dword elements. Packed SAD word results are calculated in multiples of qword superblocks, producing 4 SAD word results in each 64-bit superblock of the destination register.

Within each super block of packed word results, the SAD results from two 32-bit dword elements are calculated as follows:

The first source operand is a ZMM/YMM/XMM register. The second source operand is a ZMM/YMM/XMM register, or a 512/256/128-bit memory location. The destination operand is conditionally updated based on writemask k1 at 16-bit word granularity.

127+128*n

95+128*n

63+128*n

31+128*n

128*n

128-bit Lane of Src2

DW0

DW3

DW1

DW2

00B: DW0 01B: DW1 10B: DW2

imm8 shuffle control

11B: DW3

7

5

3

1

0

127+128*n

95+128*n

63+128*n

31+128*n

128*n

128-bit Lane of Tmp1

Tmp1 qword superblock

39

31

23

15

8

55

47

39

31

24

Tmp1 sliding dword

Tmp1 sliding dword

31

23

15

7

0

63

55

47

39

32

Src1 stationary dword 0

Src1 stationary dword 1

_

_

_

_

_

_

_

_

abs

abs

abs

abs

abs

abs

abs

abs

+

+

47

39

31

23

16

31

23

15

7

0

Tmp1 sliding dword

Tmp1 sliding dword

63

55

47

39

32

31

23

15

7

0

Src1 stationary dword 1

Src1 stationary dword 0

_

_

_

_

_

_

_

_

abs

abs

abs

abs

abs

abs

abs

abs

+

+

63

47

31

15

0

Destination qword superblock

Figure 5-8. 64-bit Super Block of SAD Operation in VDBPSADBW

Operation

VDBPSADBW (EVEX Encoded Versions)

(KL, VL) = (8, 128), (16, 256), (32, 512)
Selection of quadruplets:
FOR I = 0 to VL step 128
   TMP1[I+31:I] := select (SRC2[I+127: I], imm8[1:0])
   TMP1[I+63: I+32] := select (SRC2[I+127: I], imm8[3:2])
   TMP1[I+95: I+64] := select (SRC2[I+127: I], imm8[5:4])
   TMP1[I+127: I+96]  := select (SRC2[I+127: I], imm8[7:6])
END FOR
SAD of quadruplets:
FOR I =0 to VL step 64
   TMP_DEST[I+15:I] := ABS(SRC1[I+7: I] - TMP1[I+7: I]) +
       ABS(SRC1[I+15: I+8]- TMP1[I+15: I+8]) +
       ABS(SRC1[I+23: I+16]- TMP1[I+23: I+16]) +
       ABS(SRC1[I+31: I+24]- TMP1[I+31: I+24]) 
   TMP_DEST[I+31: I+16] := ABS(SRC1[I+7: I] - TMP1[I+15: I+8]) +
       ABS(SRC1[I+15: I+8]- TMP1[I+23: I+16]) +
       ABS(SRC1[I+23: I+16]- TMP1[I+31: I+24]) +
       ABS(SRC1[I+31: I+24]- TMP1[I+39: I+32])
   TMP_DEST[I+47: I+32] := ABS(SRC1[I+39: I+32] - TMP1[I+23: I+16]) +
       ABS(SRC1[I+47: I+40]- TMP1[I+31: I+24]) +
       ABS(SRC1[I+55: I+48]- TMP1[I+39: I+32]) +
       ABS(SRC1[I+63: I+56]- TMP1[I+47: I+40]) 
   TMP_DEST[I+63: I+48] := ABS(SRC1[I+39: I+32] - TMP1[I+31: I+24]) +
       ABS(SRC1[I+47: I+40] - TMP1[I+39: I+32]) +
       ABS(SRC1[I+55: I+48] - TMP1[I+47: I+40]) +
       ABS(SRC1[I+63: I+56] - TMP1[I+55: I+48])
ENDFOR
FOR j :=  0 TO KL-1
   i :=   j * 16
   IF k1[j] OR *no writemask*
       THEN DEST[i+15:i] :=  TMP_DEST[i+15:i]
       ELSE 
            IF *merging-masking*                ; merging-masking
                THEN *DEST[i+15:i] remains unchanged*
                ELSE                            ; zeroing-masking
                     DEST[i+15:i] :=  0
            FI
   FI;
ENDFOR
DEST[MAXVL-1:VL] :=  0

Intel C/C++ Compiler Intrinsic Equivalent

VDBPSADBW __m512i _mm512_dbsad_epu8(__m512i a, __m512i b int imm8);
VDBPSADBW __m512i _mm512_mask_dbsad_epu8(__m512i s, __mmask32 m, __m512i a, __m512i b int imm8);
VDBPSADBW __m512i _mm512_maskz_dbsad_epu8(__mmask32 m, __m512i a, __m512i b int imm8);
VDBPSADBW __m256i _mm256_dbsad_epu8(__m256i a, __m256i b int imm8);
VDBPSADBW __m256i _mm256_mask_dbsad_epu8(__m256i s, __mmask16 m, __m256i a, __m256i b int imm8);
VDBPSADBW __m256i _mm256_maskz_dbsad_epu8(__mmask16 m, __m256i a, __m256i b int imm8);
VDBPSADBW __m128i _mm_dbsad_epu8(__m128i a, __m128i b int imm8);
VDBPSADBW __m128i _mm_mask_dbsad_epu8(__m128i s, __mmask8 m, __m128i a, __m128i b int imm8);
VDBPSADBW __m128i _mm_maskz_dbsad_epu8(__mmask8 m, __m128i a, __m128i b int imm8);

SIMD Floating-Point Exceptions

None.

Other Exceptions

See Exceptions Type E4NF.nb in Table 2-50, "Type E4NF Class Exception Conditions."