VPDPBUSDS

VPDPBUSDS — Multiply and Add Unsigned and Signed Bytes with Saturation

Opcode/ Instruction	Op/ En	64/32 bit Mode Support	CPUID Feature Flag	Description
EVEX.DDS.128.66.0F38.W0 51 /r VPDPBUSDS xmm1{k1}{z}, xmm2, xmm3/m128/m32bcst	A	V/V	AVX512_VNNI AVX512VL	Multiply groups of 4 pairs signed bytes in xmm3/m128/m32bcst with corresponding unsigned bytes of xmm2, summing those products and adding them to doubleword result, with signed saturation in xmm1, under writemask k1.
EVEX.DDS.256.66.0F38.W0 51 /r VPDPBUSDS ymm1{k1}{z}, ymm2, ymm3/m256/m32bcst	A	V/V	AVX512_VNNI AVX512VL	Multiply groups of 4 pairs signed bytes in ymm3/m256/m32bcst with corresponding unsigned bytes of ymm2, summing those products and adding them to doubleword result, with signed saturation in ymm1, under writemask k1.
EVEX.DDS.512.66.0F38.W0 51 /r VPDPBUSDS zmm1{k1}{z}, zmm2, zmm3/m512/m32bcst	A	V/V	AVX512_VNNI	Multiply groups of 4 pairs signed bytes in zmm3/m512/m32bcst with corresponding unsigned bytes of zmm2, summing those products and adding them to doubleword result, with signed saturation in zmm1, under writemask k1.

Instruction Operand Encoding

Op/En	Tuple	Operand 1	Operand 2	Operand 3	Operand 4
A	Full	ModRM:reg (r, w)	EVEX.vvvv (r)	ModRM:r/m (r)	NA

Description

Multiplies the individual unsigned bytes of the first source operand by the corresponding signed bytes of the second source operand, producing intermediate signed word results. The word results are then summed and accumulated in the destination dword element size operand. If the intermediate sum overflows a 32b signed number the result is saturated to either 0x7FFF_FFFF for positive numbers of 0x8000_0000 for negative numbers.

This instruction supports memory fault suppression.

Operation

VPDPBUSDS dest, src1, src2

(KL,VL)=(4,128), (8,256), (16,512)
ORIGDEST ← DEST
FOR i ← 0 TO KL-1:
    IF k1[i] or *no writemask*:
        // Byte elements of SRC1 are zero-extended to 16b and
        // byte elements of SRC2 are sign extended to 16b before multiplication.
        IF SRC2 is memory and EVEX.b == 1:
            t ← SRC2.dword[0]
        ELSE:
            t ← SRC2.dword[i]
        p1word ← ZERO_EXTEND(SRC1.byte[4*i]) * SIGN_EXTEND(t.byte[0])
        p2word ← ZERO_EXTEND(SRC1.byte[4*i+1]) * SIGN_EXTEND(t.byte[1])
        p3word ← ZERO_EXTEND(SRC1.byte[4*i+2]) * SIGN_EXTEND(t.byte[2])
        p4word ← ZERO_EXTEND(SRC1.byte[4*i+3]) *SIGN_EXTEND(t.byte[3])
        DEST.dword[i] ← SIGNED_DWORD_SATURATE(ORIGDEST.dword[i] + p1word + p2word + p3word + p4word)
    ELSE IF *zeroing*:
        DEST.dword[i] ← 0
    ELSE: 
            // Merge masking, dest element unchanged
        DEST.dword[i] ← ORIGDEST.dword[i]
DEST[MAX_VL-1:VL] ← 0

Intel C/C++ Compiler Intrinsic Equivalent

VPDPBUSDS __m128i _mm_dpbusds_epi32(__m128i, __m128i, __m128i);
VPDPBUSDS __m128i _mm_mask_dpbusds_epi32(__m128i, __mmask8, __m128i, __m128i);
VPDPBUSDS __m128i _mm_maskz_dpbusds_epi32(__mmask8, __m128i, __m128i, __m128i);
VPDPBUSDS __m256i _mm256_dpbusds_epi32(__m256i, __m256i, __m256i);
VPDPBUSDS __m256i _mm256_mask_dpbusds_epi32(__m256i, __mmask8, __m256i, __m256i);
VPDPBUSDS __m256i _mm256_maskz_dpbusds_epi32(__mmask8, __m256i, __m256i, __m256i);
VPDPBUSDS __m512i _mm512_dpbusds_epi32(__m512i, __m512i, __m512i);
VPDPBUSDS __m512i _mm512_mask_dpbusds_epi32(__m512i, __mmask16, __m512i, __m512i);
VPDPBUSDS __m512i _mm512_maskz_dpbusds_epi32(__mmask16, __m512i, __m512i, __m512i);

SIMD Floating-Point Exceptions

None.

Other Exceptions

See Exceptions Type E4.

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Source: Intel® Architecture Instruction Set Extensions and Future Features Programming Reference (May 2018)
Generated: 5-6-2018