[API Proposal]: Expose remaining AVX512-VBMI2 hardware instructions

[MadProbe]

Background and motivation

There are approved and soon to be added AVX512-VBMI2 Compress & Expand intrinsics as part of new vector mask proposal. There is little reason if at all to not to add the left-over instructions from AVX512-VBMI2 instruction set.
Notice:

1. LeftLower and RightUpeer versions don't exist and can be replaced by lower << count and upper >> count, which produce the same result and the other operand is unused.

API Proposal

namespace System.Runtime.Intrinsics.X86
{
    [Intrinsic]
    public abstract class Avx512Vbmi2 : Avx512BW
    {
        public static new bool IsSupported { get => IsSupported; }

        [Intrinsic]
        public new abstract class X64 : Avx512BW.X64
        {
            public static new bool IsSupported { get => IsSupported; }
        }

        [Intrinsic]
        public new abstract class VL : Avx512BW.VL
        {
            public static new bool IsSupported { get => IsSupported; }

            /// <summary>
            /// __m128i _mm512_shldi_epi16 (__m128i a, __m128i b, int imm8)
            /// VPSHLDW xmm, xmm, xmm/m128, imm8
            /// </summary>
            public static Vector128<ushort> ConcatenateShiftLeftUpper(Vector128<ushort> upper, Vector128<ushort> lower, [ConstantExpected] byte count) => ConcatenateShiftLeftUpper(upper, lower, count);

            /// <summary>
            /// __m256i _mm512_shldi_epi16 (__m256i a, __m256i b, int imm8)
            /// VPSHLDW ymm, ymm, ymm/m256, imm8
            /// </summary>
            public static Vector256<ushort> ConcatenateShiftLeftUpper(Vector256<ushort> upper, Vector256<ushort> lower, [ConstantExpected] byte count) => ConcatenateShiftLeftUpper(upper, lower, count);

            /// <summary>
            /// __m128i _mm512_shldi_epi32 (__m128i a, __m128i b, int imm8)
            /// VPSHLDD xmm, xmm, xmm/m128, imm8
            /// </summary>
            public static Vector128<uint> ConcatenateShiftLeftUpper(Vector128<uint> upper, Vector128<uint> lower, [ConstantExpected] byte count) => ConcatenateShiftLeftUpper(upper, lower, count);

            /// <summary>
            /// __m256i _mm512_shldi_epi32 (__m256i a, __m256i b, int imm8)
            /// VPSHLDD ymm, ymm, ymm/m256, imm8
            /// </summary>
            public static Vector256<uint> ConcatenateShiftLeftUpper(Vector256<uint> upper, Vector256<uint> lower, [ConstantExpected] byte count) => ConcatenateShiftLeftUpper(upper, lower, count);

            /// <summary>
            /// __m128i _mm512_shldi_epi64 (__m128i a, __m128i b, int imm8)
            /// VPSHLDQ xmm, xmm, xmm/m128, imm8
            /// </summary>
            public static Vector128<ulong> ConcatenateShiftLeftUpper(Vector128<ulong> upper, Vector128<ulong> lower, [ConstantExpected] byte count) => ConcatenateShiftLeftUpper(upper, lower, count);

            /// <summary>
            /// __m256i _mm512_shldi_epi64 (__m256i a, __m256i b, int imm8)
            /// VPSHLDQ ymm, ymm, ymm/m256, imm8
            /// </summary>
            public static Vector256<ulong> ConcatenateShiftLeftUpper(Vector256<ulong> upper, Vector256<ulong> lower, [ConstantExpected] byte count) => ConcatenateShiftLeftUpper(upper, lower, count);

            /// <summary>
            /// __m128i _mm512_shrdi_epi16 (__m128i a, __m128i b, int imm8)
            /// VPSHRDW xmm, xmm, xmm/m128, imm8
            /// </summary>
            public static Vector128<ushort> ConcatenateShiftRightLower(Vector128<ushort> upper, Vector128<ushort> lower, [ConstantExpected] byte count) => ConcatenateShiftRightLower(upper, lower, count);

            /// <summary>
            /// __m256i _mm512_shrdi_epi16 (__m256i a, __m256i b, int imm8)
            /// VPSHRDW ymm, ymm, ymm/m256, imm8
            /// </summary>
            public static Vector256<ushort> ConcatenateShiftRightLower(Vector256<ushort> upper, Vector256<ushort> lower, [ConstantExpected] byte count) => ConcatenateShiftRightLower(upper, lower, count);

            /// <summary>
            /// __m128i _mm512_shrdi_epi32 (__m128i a, __m128i b, int imm8)
            /// VPSHRDD xmm, xmm, xmm/m128, imm8
            /// </summary>
            public static Vector128<uint> ConcatenateShiftRightLower(Vector128<uint> upper, Vector128<uint> lower, [ConstantExpected] byte count) => ConcatenateShiftRightLower(upper, lower, count);

            /// <summary>
            /// __m256i _mm512_shrdi_epi32 (__m256i a, __m256i b, int imm8)
            /// VPSHRDD ymm, ymm, ymm/m256, imm8
            /// </summary>
            public static Vector256<uint> ConcatenateShiftRightLower(Vector256<uint> upper, Vector256<uint> lower, [ConstantExpected] byte count) => ConcatenateShiftRightLower(upper, lower, count);

            /// <summary>
            /// __m128i _mm512_shrdi_epi64 (__m128i a, __m128i b, int imm8)
            /// VPSHRDQ xmm, xmm, xmm/m128, imm8
            /// </summary>
            public static Vector128<ulong> ConcatenateShiftRightLower(Vector128<ulong> upper, Vector128<ulong> lower, [ConstantExpected] byte count) => ConcatenateShiftRightLower(upper, lower, count);

            /// <summary>
            /// __m256i _mm512_shrdi_epi64 (__m256i a, __m256i b, int imm8)
            /// VPSHRDQ ymm, ymm, ymm/m256, imm8
            /// </summary>
            public static Vector256<ulong> ConcatenateShiftRightLower(Vector256<ulong> upper, Vector256<ulong> lower, [ConstantExpected] byte count) => ConcatenateShiftRightLower(upper, lower, count);

            /// <summary>
            /// __m128i _mm512_shldv_epi16 (__m128i a, __m128i b, __m128i c)
            /// VPSHLDVW xmm, xmm, xmm/m128
            /// </summary>
            public static Vector128<ushort> ConcatenateShiftLeftUpperVariable(Vector128<ushort> upper, Vector128<ushort> lower, Vector128<ushort> count) => ConcatenateShiftLeftUpperVariable(upper, lower, count);

            /// <summary>
            /// __m256i _mm512_shldv_epi16 (__m256i a, __m256i b, __m256i c)
            /// VPSHLDVW ymm, ymm, ymm/m256
            /// </summary>
            public static Vector256<ushort> ConcatenateShiftLeftUpperVariable(Vector256<ushort> upper, Vector256<ushort> lower, Vector256<ushort> count) => ConcatenateShiftLeftUpperVariable(upper, lower, count);

            /// <summary>
            /// __m128i _mm512_shldv_epi32 (__m128i a, __m128i b, __m128i c)
            /// VPSHLDVD xmm, xmm, xmm/m128
            /// </summary>
            public static Vector128<uint> ConcatenateShiftLeftUpperVariable(Vector128<uint> upper, Vector128<uint> lower, Vector128<uint> count) => ConcatenateShiftLeftUpperVariable(upper, lower, count);

            /// <summary>
            /// __m256i _mm512_shldv_epi32 (__m256i a, __m256i b, __m256i c)
            /// VPSHLDVD ymm, ymm, ymm/m256
            /// </summary>
            public static Vector256<uint> ConcatenateShiftLeftUpperVariable(Vector256<uint> upper, Vector256<uint> lower, Vector256<uint> count) => ConcatenateShiftLeftUpperVariable(upper, lower, count);

            /// <summary>
            /// __m128i _mm512_shldv_epi64 (__m128i a, __m128i b, __m128i c)
            /// VPSHLDVQ xmm, xmm, xmm/m128
            /// </summary>
            public static Vector128<ulong> ConcatenateShiftLeftUpperVariable(Vector128<ulong> upper, Vector128<ulong> lower, Vector128<ulong> count) => ConcatenateShiftLeftUpperVariable(upper, lower, count);

            /// <summary>
            /// __m256i _mm512_shldv_epi64 (__m256i a, __m256i b, __m256i c)
            /// VPSHLDVQ ymm, ymm, ymm/m256
            /// </summary>
            public static Vector256<ulong> ConcatenateShiftLeftUpperVariable(Vector256<ulong> upper, Vector256<ulong> lower, Vector256<ulong> count) => ConcatenateShiftLeftUpperVariable(upper, lower, count);

            /// <summary>
            /// __m128i _mm512_shrdv_epi16 (__m128i a, __m128i b, __m128i c)
            /// VPSHLDVW xmm, xmm, xmm/m128
            /// </summary>
            public static Vector128<ushort> ConcatenateShiftRightLowerVariable(Vector128<ushort> upper, Vector128<ushort> lower, Vector128<ushort> count) => ConcatenateShiftRightLowerVariable(upper, lower, count);

            /// <summary>
            /// __m256i _mm512_shrdv_epi16 (__m256i a, __m256i b, __m256i c)
            /// VPSHLDVW ymm, ymm, ymm/m256
            /// </summary>
            public static Vector256<ushort> ConcatenateShiftRightLowerVariable(Vector256<ushort> upper, Vector256<ushort> lower, Vector256<ushort> count) => ConcatenateShiftRightLowerVariable(upper, lower, count);

            /// <summary>
            /// __m128i _mm512_shrdv_epi32 (__m128i a, __m128i b, __m128i c)
            /// VPSHLDVD xmm, xmm, xmm/m128
            /// </summary>
            public static Vector128<uint> ConcatenateShiftRightLowerVariable(Vector128<uint> upper, Vector128<uint> lower, Vector128<uint> count) => ConcatenateShiftRightLowerVariable(upper, lower, count);

            /// <summary>
            /// __m256i _mm512_shrdv_epi32 (__m256i a, __m256i b, __m256i c)
            /// VPSHLDVD ymm, ymm, ymm/m256
            /// </summary>
            public static Vector256<uint> ConcatenateShiftRightLowerVariable(Vector256<uint> upper, Vector256<uint> lower, Vector256<uint> count) => ConcatenateShiftRightLowerVariable(upper, lower, count);

            /// <summary>
            /// __m128i _mm512_shrdv_epi64 (__m128i a, __m128i b, __m128i c)
            /// VPSHLDVQ xmm, xmm, xmm/m128
            /// </summary>
            public static Vector128<ulong> ConcatenateShiftRightLowerVariable(Vector128<ulong> upper, Vector128<ulong> lower, Vector128<ulong> count) => ConcatenateShiftRightLowerVariable(upper, lower, count);

            /// <summary>
            /// __m256i _mm512_shrdv_epi64 (__m256i a, __m256i b, __m256i c)
            /// VPSHLDVQ ymm, ymm, ymm/m256
            /// </summary>
            public static Vector256<ulong> ConcatenateShiftRightLowerVariable(Vector256<ulong> upper, Vector256<ulong> lower, Vector256<ulong> count) => ConcatenateShiftRightLowerVariable(upper, lower, count);
        }

        /// <summary>
        /// __m512i _mm512_shldi_epi16 (__m512i a, __m512i b, int imm8)
        /// VPSHLDW zmm, zmm, zmm/m512, imm8
        /// </summary>
        public static Vector512<ushort> ConcatenateShiftLeftUpper(Vector512<ushort> upper, Vector512<ushort> lower, [ConstantExpected] byte count) => ConcatenateShiftLeftUpper(upper, lower, count);

        /// <summary>
        /// __m512i _mm512_shldi_epi32 (__m512i a, __m512i b, int imm8)
        /// VPSHLDD zmm, zmm, zmm/m512, imm8
        /// </summary>
        public static Vector512<uint> ConcatenateShiftLeftUpper(Vector512<uint> upper, Vector512<uint> lower, [ConstantExpected] byte count) => ConcatenateShiftLeftUpper(upper, lower, count);

        /// <summary>
        /// __m512i _mm512_shldi_epi64 (__m512i a, __m512i b, int imm8)
        /// VPSHLDQ zmm, zmm, zmm/m512, imm8
        /// </summary>
        public static Vector512<ulong> ConcatenateShiftLeftUpper(Vector512<ulong> upper, Vector512<ulong> lower, [ConstantExpected] byte count) => ConcatenateShiftLeftUpper(upper, lower, count);

        /// <summary>
        /// __m512i _mm512_shrdi_epi16 (__m512i a, __m512i b, int imm8)
        /// VPSHRDW zmm, zmm, zmm/m512, imm8
        /// </summary>
        public static Vector512<ushort> ConcatenateShiftRightLower(Vector512<ushort> upper, Vector512<ushort> lower, [ConstantExpected] byte count) => ConcatenateShiftRightLower(upper, lower, count);

        /// <summary>
        /// __m512i _mm512_shrdi_epi32 (__m512i a, __m512i b, int imm8)
        /// VPSHRDD zmm, zmm, zmm/m512, imm8
        /// </summary>
        public static Vector512<uint> ConcatenateShiftRightLower(Vector512<uint> upper, Vector512<uint> lower, [ConstantExpected] byte count) => ConcatenateShiftRightLower(upper, lower, count);

        /// <summary>
        /// __m512i _mm512_shrdi_epi64 (__m512i a, __m512i b, int imm8)
        /// VPSHRDQ zmm, zmm, zmm/m512, imm8
        /// </summary>
        public static Vector512<ulong> ConcatenateShiftRightLower(Vector512<ulong> upper, Vector512<ulong> lower, [ConstantExpected] byte count) => ConcatenateShiftRightLower(upper, lower, count);

        /// <summary>
        /// __m512i _mm512_shldv_epi16 (__m512i a, __m512i b, __m512i c)
        /// VPSHLDVW zmm, zmm, zmm/m512
        /// </summary>
        public static Vector512<ushort> ConcatenateShiftLeftUpperVariable(Vector512<ushort> upper, Vector512<ushort> lower, Vector512<ushort> count) => ConcatenateShiftLeftUpperVariable(upper, lower, count);

        /// <summary>
        /// __m512i _mm512_shldv_epi32 (__m512i a, __m512i b, __m512i c)
        /// VPSHLDVD zmm, zmm, zmm/m512
        /// </summary>
        public static Vector512<uint> ConcatenateShiftLeftUpperVariable(Vector512<uint> upper, Vector512<uint> lower, Vector512<uint> count) => ConcatenateShiftLeftUpperVariable(upper, lower, count);

        /// <summary>
        /// __m512i _mm512_shldv_epi64 (__m512i a, __m512i b, __m512i c)
        /// VPSHLDVQ zmm, zmm, zmm/m512
        /// </summary>
        public static Vector512<ulong> ConcatenateShiftLeftUpperVariable(Vector512<ulong> upper, Vector512<ulong> lower, Vector512<ulong> count) => ConcatenateShiftLeftUpperVariable(upper, lower, count);

        /// <summary>
        /// __m512i _mm512_shrdv_epi16 (__m512i a, __m512i b, __m512i c)
        /// VPSHLDVW zmm, zmm, zmm/m512
        /// </summary>
        public static Vector512<ushort> ConcatenateShiftRightLowerVariable(Vector512<ushort> upper, Vector512<ushort> lower, Vector512<ushort> count) => ConcatenateShiftRightLowerVariable(upper, lower, count);

        /// <summary>
        /// __m512i _mm512_shrdv_epi32 (__m512i a, __m512i b, __m512i c)
        /// VPSHLDVD zmm, zmm, zmm/m512
        /// </summary>
        public static Vector512<uint> ConcatenateShiftRightLowerVariable(Vector512<uint> upper, Vector512<uint> lower, Vector512<uint> count) => ConcatenateShiftRightLowerVariable(upper, lower, count);

        /// <summary>
        /// __m512i _mm512_shrdv_epi64 (__m512i a, __m512i b, __m512i c)
        /// VPSHLDVQ zmm, zmm, zmm/m512
        /// </summary>
        public static Vector512<ulong> ConcatenateShiftRightLowerVariable(Vector512<ulong> upper, Vector512<ulong> lower, Vector512<ulong> count) => ConcatenateShiftRightLowerVariable(upper, lower, count);
    }
}

API Usage

// Avx512Vbmi2.ConcatenateShift(LeftUpper/RightLower)(...) example
Vector512<ushort> some_data = GetData(), some_data2 = GetData();
// result consists of lower 8 bit part of ushort data in upper_data and upper 8 bit of ushort data in lower_data
// shift count can be changed to get count of lower bits of ushort data in upper_data and upper 16 - count bit of ushort data in lower_data
var result = Avx512Vbmi2.ConcatenateShiftLeftUpper(upper_data, lower_data, 8);

Alternative Designs

N/A

Risks

N/A

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Issue Details

---

Background and motivation

There is already present AVX512-VBMI PermuteVar64x8(x2) intrinsics and approved and soon to be added AVX512-VBMI2 Compress & Expand intrinsics as part of new vector mask proposal. There is little reason if at all to not to add the left-over instructions from aforementioned instruction sets.
Notice:

1. LeftLower and RightUpeer versions don't exist and can be replaced by lower << count and upper >> count, which produce the same result and the other operand is unused.
2. I saw MultipleShift discussed in API Review stream, but I can't find it anywhere: Am I not searching hard enough or is it lost into oblivion?

API Proposal

namespace System.Runtime.Intrinsics.X86
{
    [Intrinsic]
    public abstract class Avx512Vbmi : Avx512BW
    {
        public static new bool IsSupported { get => IsSupported; }

        [Intrinsic]
        public new abstract class X64 : Avx512BW.X64
        {
            public static new bool IsSupported { get => IsSupported; }
        }

        [Intrinsic]
        public new abstract class VL : Avx512BW.VL
        {
            public static new bool IsSupported { get => IsSupported; }

            /// <summary>
            /// __m128i _mm128_multishift_epi64_epi8 (__m128i a, __m128i b)
            /// VPMULTISHIFTQB xmm, xmm, xmm
            /// </summary>
            public static Vector128<byte> MultipleShift(Vector128<byte> control, Vector128<byte> source) => MultipleShift(control, source);

            /// <summary>
            /// __m256i _mm256_multishift_epi64_epi8 (__m256i a, __m256i b)
            /// VPMULTISHIFTQB ymm, ymm, ymm
            /// </summary>
            public static Vector256<byte> MultipleShift(Vector256<byte> control, Vector256<byte> source) => MultipleShift(control, source);
        }

        /// <summary>
        /// __m512i _mm512_multishift_epi64_epi8 (__m512i a, __m512i b)
        /// VPMULTISHIFTQB zmm, zmm, zmm
        /// </summary>
        public static Vector512<byte> MultipleShift(Vector512<byte> control, Vector512<byte> source) => MultipleShift(control, source);
    }
    [Intrinsic]
    public abstract class Avx512Vbmi2 : Avx512BW
    {
        public static new bool IsSupported { get => IsSupported; }

        [Intrinsic]
        public new abstract class X64 : Avx512BW.X64
        {
            public static new bool IsSupported { get => IsSupported; }
        }

        [Intrinsic]
        public new abstract class VL : Avx512BW.VL
        {
            public static new bool IsSupported { get => IsSupported; }

            /// <summary>
            /// __m128i _mm512_shldi_epi16 (__m128i a, __m128i b, int imm8)
            /// VPSHLDW xmm, xmm, xmm, imm8
            /// </summary>
            public static Vector128<ushort> ConcatenateShiftLeftUpper(Vector128<ushort> upper, Vector128<ushort> lower, [ConstantExpected] byte count) => ConcatenateShiftLeftUpper(upper, lower, count);

            /// <summary>
            /// __m256i _mm512_shldi_epi16 (__m256i a, __m256i b, int imm8)
            /// VPSHLDW ymm, ymm, ymm, imm8
            /// </summary>
            public static Vector256<ushort> ConcatenateShiftLeftUpper(Vector256<ushort> upper, Vector256<ushort> lower, [ConstantExpected] byte count) => ConcatenateShiftLeftUpper(upper, lower, count);

            /// <summary>
            /// __m128i _mm512_shldi_epi32 (__m128i a, __m128i b, int imm8)
            /// VPSHLDD xmm, xmm, xmm, imm8
            /// </summary>
            public static Vector128<uint> ConcatenateShiftLeftUpper(Vector128<uint> upper, Vector128<uint> lower, [ConstantExpected] byte count) => ConcatenateShiftLeftUpper(upper, lower, count);

            /// <summary>
            /// __m256i _mm512_shldi_epi32 (__m256i a, __m256i b, int imm8)
            /// VPSHLDD ymm, ymm, ymm, imm8
            /// </summary>
            public static Vector256<uint> ConcatenateShiftLeftUpper(Vector256<uint> upper, Vector256<uint> lower, [ConstantExpected] byte count) => ConcatenateShiftLeftUpper(upper, lower, count);

            /// <summary>
            /// __m128i _mm512_shldi_epi64 (__m128i a, __m128i b, int imm8)
            /// VPSHLDQ xmm, xmm, xmm, imm8
            /// </summary>
            public static Vector128<ulong> ConcatenateShiftLeftUpper(Vector128<ulong> upper, Vector128<ulong> lower, [ConstantExpected] byte count) => ConcatenateShiftLeftUpper(upper, lower, count);

            /// <summary>
            /// __m256i _mm512_shldi_epi64 (__m256i a, __m256i b, int imm8)
            /// VPSHLDQ ymm, ymm, ymm, imm8
            /// </summary>
            public static Vector256<ulong> ConcatenateShiftLeftUpper(Vector256<ulong> upper, Vector256<ulong> lower, [ConstantExpected] byte count) => ConcatenateShiftLeftUpper(upper, lower, count);

            /// <summary>
            /// __m128i _mm512_shrdi_epi16 (__m128i a, __m128i b, int imm8)
            /// VPSHRDW xmm, xmm, xmm, imm8
            /// </summary>
            public static Vector128<ushort> ConcatenateShiftRightLower(Vector128<ushort> upper, Vector128<ushort> lower, [ConstantExpected] byte count) => ConcatenateShiftRightLower(upper, lower, count);

            /// <summary>
            /// __m256i _mm512_shrdi_epi16 (__m256i a, __m256i b, int imm8)
            /// VPSHRDW ymm, ymm, ymm, imm8
            /// </summary>
            public static Vector256<ushort> ConcatenateShiftRightLower(Vector256<ushort> upper, Vector256<ushort> lower, [ConstantExpected] byte count) => ConcatenateShiftRightLower(upper, lower, count);

            /// <summary>
            /// __m128i _mm512_shrdi_epi32 (__m128i a, __m128i b, int imm8)
            /// VPSHRDD xmm, xmm, xmm, imm8
            /// </summary>
            public static Vector128<uint> ConcatenateShiftRightLower(Vector128<uint> upper, Vector128<uint> lower, [ConstantExpected] byte count) => ConcatenateShiftRightLower(upper, lower, count);

            /// <summary>
            /// __m256i _mm512_shrdi_epi32 (__m256i a, __m256i b, int imm8)
            /// VPSHRDD ymm, ymm, ymm, imm8
            /// </summary>
            public static Vector256<uint> ConcatenateShiftRightLower(Vector256<uint> upper, Vector256<uint> lower, [ConstantExpected] byte count) => ConcatenateShiftRightLower(upper, lower, count);

            /// <summary>
            /// __m128i _mm512_shrdi_epi64 (__m128i a, __m128i b, int imm8)
            /// VPSHRDQ xmm, xmm, xmm, imm8
            /// </summary>
            public static Vector128<ulong> ConcatenateShiftRightLower(Vector128<ulong> upper, Vector128<ulong> lower, [ConstantExpected] byte count) => ConcatenateShiftRightLower(upper, lower, count);

            /// <summary>
            /// __m256i _mm512_shrdi_epi64 (__m256i a, __m256i b, int imm8)
            /// VPSHRDQ ymm, ymm, ymm, imm8
            /// </summary>
            public static Vector256<ulong> ConcatenateShiftRightLower(Vector256<ulong> upper, Vector256<ulong> lower, [ConstantExpected] byte count) => ConcatenateShiftRightLower(upper, lower, count);

            /// <summary>
            /// __m128i _mm512_shldv_epi16 (__m128i a, __m128i b, __m128i c)
            /// VPSHLDVW xmm, xmm, xmm
            /// </summary>
            public static Vector128<ushort> ConcatenateShiftLeftUpperVariable(Vector128<ushort> upper, Vector128<ushort> lower, Vector128<ushort> count) => ConcatenateShiftLeftUpperVariable(upper, lower, count);

            /// <summary>
            /// __m256i _mm512_shldv_epi16 (__m256i a, __m256i b, __m256i c)
            /// VPSHLDVW ymm, ymm, ymm
            /// </summary>
            public static Vector256<ushort> ConcatenateShiftLeftUpperVariable(Vector256<ushort> upper, Vector256<ushort> lower, Vector256<ushort> count) => ConcatenateShiftLeftUpperVariable(upper, lower, count);

            /// <summary>
            /// __m128i _mm512_shldv_epi32 (__m128i a, __m128i b, __m128i c)
            /// VPSHLDVD xmm, xmm, xmm
            /// </summary>
            public static Vector128<uint> ConcatenateShiftLeftUpperVariable(Vector128<uint> upper, Vector128<uint> lower, Vector128<uint> count) => ConcatenateShiftLeftUpperVariable(upper, lower, count);

            /// <summary>
            /// __m256i _mm512_shldv_epi32 (__m256i a, __m256i b, __m256i c)
            /// VPSHLDVD ymm, ymm, ymm
            /// </summary>
            public static Vector256<uint> ConcatenateShiftLeftUpperVariable(Vector256<uint> upper, Vector256<uint> lower, Vector256<uint> count) => ConcatenateShiftLeftUpperVariable(upper, lower, count);

            /// <summary>
            /// __m128i _mm512_shldv_epi64 (__m128i a, __m128i b, __m128i c)
            /// VPSHLDVQ xmm, xmm, xmm
            /// </summary>
            public static Vector128<ulong> ConcatenateShiftLeftUpperVariable(Vector128<ulong> upper, Vector128<ulong> lower, Vector128<ulong> count) => ConcatenateShiftLeftUpperVariable(upper, lower, count);

            /// <summary>
            /// __m256i _mm512_shldv_epi64 (__m256i a, __m256i b, __m256i c)
            /// VPSHLDVQ ymm, ymm, ymm
            /// </summary>
            public static Vector256<ulong> ConcatenateShiftLeftUpperVariable(Vector256<ulong> upper, Vector256<ulong> lower, Vector256<ulong> count) => ConcatenateShiftLeftUpperVariable(upper, lower, count);

            /// <summary>
            /// __m128i _mm512_shrdv_epi16 (__m128i a, __m128i b, __m128i c)
            /// VPSHLDVW xmm, xmm, xmm
            /// </summary>
            public static Vector128<ushort> ConcatenateShiftRightLowerVariable(Vector128<ushort> upper, Vector128<ushort> lower, Vector128<ushort> count) => ConcatenateShiftRightLowerVariable(upper, lower, count);

            /// <summary>
            /// __m256i _mm512_shrdv_epi16 (__m256i a, __m256i b, __m256i c)
            /// VPSHLDVW ymm, ymm, ymm
            /// </summary>
            public static Vector256<ushort> ConcatenateShiftRightLowerVariable(Vector256<ushort> upper, Vector256<ushort> lower, Vector256<ushort> count) => ConcatenateShiftRightLowerVariable(upper, lower, count);

            /// <summary>
            /// __m128i _mm512_shrdv_epi32 (__m128i a, __m128i b, __m128i c)
            /// VPSHLDVD xmm, xmm, xmm
            /// </summary>
            public static Vector128<uint> ConcatenateShiftRightLowerVariable(Vector128<uint> upper, Vector128<uint> lower, Vector128<uint> count) => ConcatenateShiftRightLowerVariable(upper, lower, count);

            /// <summary>
            /// __m256i _mm512_shrdv_epi32 (__m256i a, __m256i b, __m256i c)
            /// VPSHLDVD ymm, ymm, ymm
            /// </summary>
            public static Vector256<uint> ConcatenateShiftRightLowerVariable(Vector256<uint> upper, Vector256<uint> lower, Vector256<uint> count) => ConcatenateShiftRightLowerVariable(upper, lower, count);

            /// <summary>
            /// __m128i _mm512_shrdv_epi64 (__m128i a, __m128i b, __m128i c)
            /// VPSHLDVQ xmm, xmm, xmm
            /// </summary>
            public static Vector128<ulong> ConcatenateShiftRightLowerVariable(Vector128<ulong> upper, Vector128<ulong> lower, Vector128<ulong> count) => ConcatenateShiftRightLowerVariable(upper, lower, count);

            /// <summary>
            /// __m256i _mm512_shrdv_epi64 (__m256i a, __m256i b, __m256i c)
            /// VPSHLDVQ ymm, ymm, ymm
            /// </summary>
            public static Vector256<ulong> ConcatenateShiftRightLowerVariable(Vector256<ulong> upper, Vector256<ulong> lower, Vector256<ulong> count) => ConcatenateShiftRightLowerVariable(upper, lower, count);
        }

        /// <summary>
        /// __m512i _mm512_shldi_epi16 (__m512i a, __m512i b, int imm8)
        /// VPSHLDW zmm, zmm, zmm, imm8
        /// </summary>
        public static Vector512<ushort> ConcatenateShiftLeftUpper(Vector512<ushort> upper, Vector512<ushort> lower, [ConstantExpected] byte count) => ConcatenateShiftLeftUpper(upper, lower, count);

        /// <summary>
        /// __m512i _mm512_shldi_epi32 (__m512i a, __m512i b, int imm8)
        /// VPSHLDD zmm, zmm, zmm, imm8
        /// </summary>
        public static Vector512<uint> ConcatenateShiftLeftUpper(Vector512<uint> upper, Vector512<uint> lower, [ConstantExpected] byte count) => ConcatenateShiftLeftUpper(upper, lower, count);

        /// <summary>
        /// __m512i _mm512_shldi_epi64 (__m512i a, __m512i b, int imm8)
        /// VPSHLDQ zmm, zmm, zmm, imm8
        /// </summary>
        public static Vector512<ulong> ConcatenateShiftLeftUpper(Vector512<ulong> upper, Vector512<ulong> lower, [ConstantExpected] byte count) => ConcatenateShiftLeftUpper(upper, lower, count);

        /// <summary>
        /// __m512i _mm512_shrdi_epi16 (__m512i a, __m512i b, int imm8)
        /// VPSHRDW zmm, zmm, zmm, imm8
        /// </summary>
        public static Vector512<ushort> ConcatenateShiftRightLower(Vector512<ushort> upper, Vector512<ushort> lower, [ConstantExpected] byte count) => ConcatenateShiftRightLower(upper, lower, count);

        /// <summary>
        /// __m512i _mm512_shrdi_epi32 (__m512i a, __m512i b, int imm8)
        /// VPSHRDD zmm, zmm, zmm, imm8
        /// </summary>
        public static Vector512<uint> ConcatenateShiftRightLower(Vector512<uint> upper, Vector512<uint> lower, [ConstantExpected] byte count) => ConcatenateShiftRightLower(upper, lower, count);

        /// <summary>
        /// __m512i _mm512_shrdi_epi64 (__m512i a, __m512i b, int imm8)
        /// VPSHRDQ zmm, zmm, zmm, imm8
        /// </summary>
        public static Vector512<ulong> ConcatenateShiftRightLower(Vector512<ulong> upper, Vector512<ulong> lower, [ConstantExpected] byte count) => ConcatenateShiftRightLower(upper, lower, count);

        /// <summary>
        /// __m512i _mm512_shldv_epi16 (__m512i a, __m512i b, __m512i c)
        /// VPSHLDVW zmm, zmm, zmm
        /// </summary>
        public static Vector512<ushort> ConcatenateShiftLeftUpperVariable(Vector512<ushort> upper, Vector512<ushort> lower, Vector512<ushort> count) => ConcatenateShiftLeftUpperVariable(upper, lower, count);

        /// <summary>
        /// __m512i _mm512_shldv_epi32 (__m512i a, __m512i b, __m512i c)
        /// VPSHLDVD zmm, zmm, zmm
        /// </summary>
        public static Vector512<uint> ConcatenateShiftLeftUpperVariable(Vector512<uint> upper, Vector512<uint> lower, Vector512<uint> count) => ConcatenateShiftLeftUpperVariable(upper, lower, count);

        /// <summary>
        /// __m512i _mm512_shldv_epi64 (__m512i a, __m512i b, __m512i c)
        /// VPSHLDVQ zmm, zmm, zmm
        /// </summary>
        public static Vector512<ulong> ConcatenateShiftLeftUpperVariable(Vector512<ulong> upper, Vector512<ulong> lower, Vector512<ulong> count) => ConcatenateShiftLeftUpperVariable(upper, lower, count);

        /// <summary>
        /// __m512i _mm512_shrdv_epi16 (__m512i a, __m512i b, __m512i c)
        /// VPSHLDVW zmm, zmm, zmm
        /// </summary>
        public static Vector512<ushort> ConcatenateShiftRightLowerVariable(Vector512<ushort> upper, Vector512<ushort> lower, Vector512<ushort> count) => ConcatenateShiftRightLowerVariable(upper, lower, count);

        /// <summary>
        /// __m512i _mm512_shrdv_epi32 (__m512i a, __m512i b, __m512i c)
        /// VPSHLDVD zmm, zmm, zmm
        /// </summary>
        public static Vector512<uint> ConcatenateShiftRightLowerVariable(Vector512<uint> upper, Vector512<uint> lower, Vector512<uint> count) => ConcatenateShiftRightLowerVariable(upper, lower, count);

        /// <summary>
        /// __m512i _mm512_shrdv_epi64 (__m512i a, __m512i b, __m512i c)
        /// VPSHLDVQ zmm, zmm, zmm
        /// </summary>
        public static Vector512<ulong> ConcatenateShiftRightLowerVariable(Vector512<ulong> upper, Vector512<ulong> lower, Vector512<ulong> count) => ConcatenateShiftRightLowerVariable(upper, lower, count);
    }
}

API Usage

// Avx512Vbmi2.ConcatenateShift(LeftUpper/RightLower)(...) example
Vector512<ushort> some_data = GetData(), some_data2 = GetData();
// result consists of lower 8 bit part of ushort data in upper_data and upper 8 bit of ushort data in lower_data
// shift count can be changed to get count of lower bits of ushort data in upper_data and upper 16 - count bit of ushort data in lower_data
var result = Avx512Vbmi2.ConcatenateShiftLeftUpper(upper_data, lower_data, 8);

// Avx512Vbmi.MultipleShift(...) example
Vector512<ushort> d = GetData(), control = Vector512.Create(0x0B_1B_2B_3B_04_14_24_34);
// Given control makes every 64 bit part of result structure is this: (d[59:52], d[43:36], d[27:20], d[11:4], (d[3:0] << 4) | d[63:60], d[51:44], d[35:28], d[19:12])
var result = Avx512Vbmi.MultupleShift(control, d);

Alternative Designs

N/A

Risks

N/A

Author:	MadProbe
Assignees:	-
Labels:	api-suggestion, area-System.Runtime.Intrinsics
Milestone:	-

[tannergooding]

MultiShift is part of #86168

ConcatenateShift hasn't gone through any review yet and I need to think more on the general name, etc. It's too late in the cycle for either to land for .NET 8, however. Both will end up being .NET 9 instead.

[MadProbe]

I have deleted the duplicated MultiShift and changed the title and proposal description accordingly.

[tannergooding]

Need to give some consideration around the suggested names, but this will be a .NET 9 change regardless; so marking with needs-further-triage for the moment.

[lemire]

Note that AMD Zen 4 and better as well as Intel Ice Lake and better support VBMI2.

As motivation, this would make it possible support fast Unicode transcoding function in C#, like what is done in the simdutf library (which is part of the Node.js runtime).

See https://arxiv.org/pdf/2212.05098.pdf

cc @EgorBo