AVX and Bubble Sort

Question

I have to develop a bubble sort algorithm with AVX instructions with single precision numbers in input. Can anyone help me to look for the best implementation?

I did a bubble sort version for SSE3:

global sort32

sort32: start

    mov eax, [ebp+8]        ; float* x
    mov ebx, [ebp+12]       ; int n

    call    sort

    stop

    ; --------------------------------------------------
    ; Inserire qui il proprio algoritmo di ordinamento
    ; --------------------------------------------------
    ; eax = vector start address
    ; ebx = vector length
    ; --------------------------------------------------

sort:   
    mov edi, ebx    ;contatore ciclo esterno
    sub edi, 4

ciclo_esterno:
    mov esi, 0      ;contatore ciclo interno

ciclo_interno:
    movups  xmm0, [eax+esi*4]
    jmp     verifica

; controllo se l'array da 4 non è già ordinato
verifica:
    movaps  xmm4, xmm0
    shufps  xmm4, xmm4, 10010000b
    cmpleps xmm4, xmm0
    movmskps edx, xmm4
    cmp     edx,    15
    je  incremento  

    movaps  xmm1, xmm0
    movhlps xmm1, xmm0

    movaps  xmm4, xmm0  ;confronto
    minps   xmm0, xmm1
    maxps   xmm1, xmm4

    shufps  xmm1, xmm1, 11100001b   ;inverto i massimi e riconfronto

    movaps  xmm4, xmm0  ;confronto
    minps   xmm0, xmm1
    maxps   xmm1, xmm4

    movaps  xmm4, xmm0
    shufps  xmm4, xmm4, 11100001b   ; confronto la coppia dei minimi

    cmpltps xmm4, xmm0
    movmskps edx, xmm4
    cmp     edx, 2
    je  cmp_max
    shufps  xmm0, xmm0, 11100001b   ; non sono ordinati all'interno quindi scambio

cmp_max:
    movaps  xmm4, xmm1
    shufps  xmm4, xmm4, 11100001b   ; confronto la coppia dei massimi

    cmpltps xmm4, xmm1
    movmskps edx, xmm4
    cmp edx, 2
    je  unisci
    shufps  xmm1, xmm1, 11100001b   ; non sono ordinati all'interno quindi scambio

unisci:
    movlhps xmm0, xmm1
    movups  [eax+esi*4], xmm0

incremento: 
    inc esi
    cmp esi, edi
    jg aggiorna_edi
    jmp ciclo_interno

aggiorna_edi:
    dec edi
    cmp edi, 0
    jl endl
    jmp ciclo_esterno   

endl:   ret

Answer 1

Most sorting algorithms do not generally lend themselves to SIMD implementation. You might want to consider using a network sort algorithm instead, which is relatively simple to implement with SIMD for small numbers of elements. For larger sorts you can use the network sort as the inner "kernel" of a larger non-SIMD sort algorithm.