| Opcode/Instruction | Op /En | 64/32 bit Mode Support | CPUID Feature Flag | Description |
|---|---|---|---|---|
| EVEX.128.F3.0F38.W0 31 /r VPMOVDB xmm1/m32 {k1}{z}, xmm2 | A | V/V | AVX512VL AVX512F | Converts 4 packed double-word integers from xmm2 into 4 packed byte integers in xmm1/m32 with truncation under writemask k1. |
| EVEX.128.F3.0F38.W0 21 /r VPMOVSDB xmm1/m32 {k1}{z}, xmm2 | A | V/V | AVX512VL AVX512F | Converts 4 packed signed double-word integers from xmm2 into 4 packed signed byte integers in xmm1/m32 using signed saturation under writemask k1. |
| EVEX.128.F3.0F38.W0 11 /r VPMOVUSDB xmm1/m32 {k1}{z}, xmm2 | A | V/V | AVX512VL AVX512F | Converts 4 packed unsigned double-word integers from xmm2 into 4 packed unsigned byte integers in xmm1/m32 using unsigned saturation under writemask k1. |
| EVEX.256.F3.0F38.W0 31 /r VPMOVDB xmm1/m64 {k1}{z}, ymm2 | A | V/V | AVX512VL AVX512F | Converts 8 packed double-word integers from ymm2 into 8 packed byte integers in xmm1/m64 with truncation under writemask k1. |
| EVEX.256.F3.0F38.W0 21 /r VPMOVSDB xmm1/m64 {k1}{z}, ymm2 | A | V/V | AVX512VL AVX512F | Converts 8 packed signed double-word integers from ymm2 into 8 packed signed byte integers in xmm1/m64 using signed saturation under writemask k1. |
| EVEX.256.F3.0F38.W0 11 /r VPMOVUSDB xmm1/m64 {k1}{z}, ymm2 | A | V/V | AVX512VL AVX512F | Converts 8 packed unsigned double-word integers from ymm2 into 8 packed unsigned byte integers in xmm1/m64 using unsigned saturation under writemask k1. |
| EVEX.512.F3.0F38.W0 31 /r VPMOVDB xmm1/m128 {k1}{z}, zmm2 | A | V/V | AVX512F | Converts 16 packed double-word integers from zmm2 into 16 packed byte integers in xmm1/m128 with truncation under writemask k1. |
| EVEX.512.F3.0F38.W0 21 /r VPMOVSDB xmm1/m128 {k1}{z}, zmm2 | A | V/V | AVX512F | Converts 16 packed signed double-word integers from zmm2 into 16 packed signed byte integers in xmm1/m128 using signed saturation under writemask k1. |
| EVEX.512.F3.0F38.W0 11 /r VPMOVUSDB xmm1/m128 {k1}{z}, zmm2 | A | V/V | AVX512F | Converts 16 packed unsigned double-word integers from zmm2 into 16 packed unsigned byte integers in xmm1/m128 using unsigned saturation under writemask k1. |
| Op/En | Tuple Type | Operand 1 | Operand 2 | Operand 3 | Operand 4 |
|---|---|---|---|---|---|
| A | Quarter Mem | ModRM:r/m (w) | ModRM:reg (r) | N/A | N/A |
Description
VPMOVDB down converts 32-bit integer elements in the source operand (the second operand) into packed bytes using truncation. VPMOVSDB converts signed 32-bit integers into packed signed bytes using signed saturation. VPMOVUSDB convert unsigned double-word values into unsigned byte values using unsigned saturation.
The source operand is a ZMM/YMM/XMM register. The destination operand is a XMM register or a 128/64/32-bit memory location.
Down-converted byte elements are written to the destination operand (the first operand) from the least-significant byte. Byte elements of the destination operand are updated according to the writemask. Bits (MAXVL-1:128/64/32) of the register destination are zeroed.
EVEX.vvvv is reserved and must be 1111b otherwise instructions will #UD.
Operation
VPMOVDB instruction (EVEX encoded versions) when dest is a register
(KL, VL) = (4, 128), (8, 256), (16, 512)
FOR j := 0 TO KL-1
i := j * 8
m := j * 32
IF k1[j] OR *no writemask*
THEN DEST[i+7:i] := TruncateDoubleWordToByte (SRC[m+31:m])
ELSE
IF *merging-masking*
; merging-masking
THEN *DEST[i+7:i] remains unchanged*
ELSE *zeroing-masking*
; zeroing-masking
DEST[i+7:i] := 0
FI
FI;
ENDFOR
DEST[MAXVL-1:VL/4] := 0;
VPMOVDB instruction (EVEX encoded versions) when dest is memory
(KL, VL) = (4, 128), (8, 256), (16, 512)
FOR j := 0 TO KL-1
i := j * 8
m := j * 32
IF k1[j] OR *no writemask*
THEN DEST[i+7:i] := TruncateDoubleWordToByte (SRC[m+31:m])
ELSE *DEST[i+7:i] remains unchanged*
; merging-masking
FI;
ENDFOR
VPMOVSDB instruction (EVEX encoded versions) when dest is a register
(KL, VL) = (4, 128), (8, 256), (16, 512)
FOR j := 0 TO KL-1
i := j * 8
m := j * 32
IF k1[j] OR *no writemask*
THEN DEST[i+7:i] := SaturateSignedDoubleWordToByte (SRC[m+31:m])
ELSE
IF *merging-masking*
; merging-masking
THEN *DEST[i+7:i] remains unchanged*
ELSE *zeroing-masking*
; zeroing-masking
DEST[i+7:i] := 0
FI
FI;
ENDFOR
DEST[MAXVL-1:VL/4] := 0;
VPMOVSDB instruction (EVEX encoded versions) when dest is memory
(KL, VL) = (4, 128), (8, 256), (16, 512)
FOR j := 0 TO KL-1
i := j * 8
m := j * 32
IF k1[j] OR *no writemask*
THEN DEST[i+7:i] := SaturateSignedDoubleWordToByte (SRC[m+31:m])
ELSE *DEST[i+7:i] remains unchanged*
; merging-masking
FI;
ENDFOR
VPMOVUSDB instruction (EVEX encoded versions) when dest is a register
(KL, VL) = (4, 128), (8, 256), (16, 512)
FOR j := 0 TO KL-1
i := j * 8
m := j * 32
IF k1[j] OR *no writemask*
THEN DEST[i+7:i] := SaturateUnsignedDoubleWordToByte (SRC[m+31:m])
ELSE
IF *merging-masking*
; merging-masking
THEN *DEST[i+7:i] remains unchanged*
ELSE *zeroing-masking*
; zeroing-masking
DEST[i+7:i] := 0
FI
FI;
ENDFOR
DEST[MAXVL-1:VL/4] := 0;
VPMOVUSDB instruction (EVEX encoded versions) when dest is memory
(KL, VL) = (4, 128), (8, 256), (16, 512)
FOR j := 0 TO KL-1
i := j * 8
m := j * 32
IF k1[j] OR *no writemask*
THEN DEST[i+7:i] := SaturateUnsignedDoubleWordToByte (SRC[m+31:m])
ELSE *DEST[i+7:i] remains unchanged*
; merging-masking
FI;
ENDFOR
Intel C/C++ Compiler Intrinsic Equivalents
VPMOVDB __m128i _mm512_cvtepi32_epi8( __m512i a);
VPMOVDB __m128i _mm512_mask_cvtepi32_epi8(__m128i s, __mmask16 k, __m512i a);
VPMOVDB __m128i _mm512_maskz_cvtepi32_epi8( __mmask16 k, __m512i a);
VPMOVDB void _mm512_mask_cvtepi32_storeu_epi8(void * d, __mmask16 k, __m512i a);
VPMOVSDB __m128i _mm512_cvtsepi32_epi8( __m512i a);
VPMOVSDB __m128i _mm512_mask_cvtsepi32_epi8(__m128i s, __mmask16 k, __m512i a);
VPMOVSDB __m128i _mm512_maskz_cvtsepi32_epi8( __mmask16 k, __m512i a);
VPMOVSDB void _mm512_mask_cvtsepi32_storeu_epi8(void * d, __mmask16 k, __m512i a);
VPMOVUSDB __m128i _mm512_cvtusepi32_epi8( __m512i a);
VPMOVUSDB __m128i _mm512_mask_cvtusepi32_epi8(__m128i s, __mmask16 k, __m512i a);
VPMOVUSDB __m128i _mm512_maskz_cvtusepi32_epi8( __mmask16 k, __m512i a);
VPMOVUSDB void _mm512_mask_cvtusepi32_storeu_epi8(void * d, __mmask16 k, __m512i a);
VPMOVUSDB __m128i _mm256_cvtusepi32_epi8(__m256i a);
VPMOVUSDB __m128i _mm256_mask_cvtusepi32_epi8(__m128i a, __mmask8 k, __m256i b);
VPMOVUSDB __m128i _mm256_maskz_cvtusepi32_epi8( __mmask8 k, __m256i b);
VPMOVUSDB void _mm256_mask_cvtusepi32_storeu_epi8(void * , __mmask8 k, __m256i b);
VPMOVUSDB __m128i _mm_cvtusepi32_epi8(__m128i a);
VPMOVUSDB __m128i _mm_mask_cvtusepi32_epi8(__m128i a, __mmask8 k, __m128i b);
VPMOVUSDB __m128i _mm_maskz_cvtusepi32_epi8( __mmask8 k, __m128i b);
VPMOVUSDB void _mm_mask_cvtusepi32_storeu_epi8(void * , __mmask8 k, __m128i b);
VPMOVSDB __m128i _mm256_cvtsepi32_epi8(__m256i a);
VPMOVSDB __m128i _mm256_mask_cvtsepi32_epi8(__m128i a, __mmask8 k, __m256i b);
VPMOVSDB __m128i _mm256_maskz_cvtsepi32_epi8( __mmask8 k, __m256i b);
VPMOVSDB void _mm256_mask_cvtsepi32_storeu_epi8(void * , __mmask8 k, __m256i b);
VPMOVSDB __m128i _mm_cvtsepi32_epi8(__m128i a);
VPMOVSDB __m128i _mm_mask_cvtsepi32_epi8(__m128i a, __mmask8 k, __m128i b);
VPMOVSDB __m128i _mm_maskz_cvtsepi32_epi8( __mmask8 k, __m128i b);
VPMOVSDB void _mm_mask_cvtsepi32_storeu_epi8(void * , __mmask8 k, __m128i b);
VPMOVDB __m128i _mm256_cvtepi32_epi8(__m256i a);
VPMOVDB __m128i _mm256_mask_cvtepi32_epi8(__m128i a, __mmask8 k, __m256i b);
VPMOVDB __m128i _mm256_maskz_cvtepi32_epi8( __mmask8 k, __m256i b);
VPMOVDB void _mm256_mask_cvtepi32_storeu_epi8(void * , __mmask8 k, __m256i b);
VPMOVDB __m128i _mm_cvtepi32_epi8(__m128i a);
VPMOVDB __m128i _mm_mask_cvtepi32_epi8(__m128i a, __mmask8 k, __m128i b);
VPMOVDB __m128i _mm_maskz_cvtepi32_epi8( __mmask8 k, __m128i b);
VPMOVDB void _mm_mask_cvtepi32_storeu_epi8(void * , __mmask8 k, __m128i b);
SIMD Floating-Point Exceptions
None.
Other Exceptions
EVEX-encoded instruction, see Table 2-53, “Type E6 Class Exception Conditions.”
Additionally:
| #UD | If EVEX.vvvv != 1111B. |