How to do cross multiplication in neon?











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Now, I have two 8bit arrays



One is 



A[8] = {1,2,3,4,5,6,7,8}


Another is 



B[2] = {1,2}


What I want to calculate is that: 



C = A x B = {1,2,3,4,5,6,7,8} x {1, 2, 1, 2, 1, 2, 1, 2} = {1,4,3,8,5,12,7,16}


How to do this using armv7 simd
efficiently?






simd neon armv7







share|improve this question




























    up vote
    0
    down vote

    favorite












    Now, I have two 8bit arrays



    One is 



    A[8] = {1,2,3,4,5,6,7,8}


    Another is 



    B[2] = {1,2}


    What I want to calculate is that: 



    C = A x B = {1,2,3,4,5,6,7,8} x {1, 2, 1, 2, 1, 2, 1, 2} = {1,4,3,8,5,12,7,16}


    How to do this using armv7 simd
    efficiently?






    simd neon armv7







    share|improve this question


























      up vote
      0
      down vote

      favorite









      up vote
      0
      down vote

      favorite











      Now, I have two 8bit arrays



      One is 



      A[8] = {1,2,3,4,5,6,7,8}


      Another is 



      B[2] = {1,2}


      What I want to calculate is that: 



      C = A x B = {1,2,3,4,5,6,7,8} x {1, 2, 1, 2, 1, 2, 1, 2} = {1,4,3,8,5,12,7,16}


      How to do this using armv7 simd
      efficiently?






      simd neon armv7







      share|improve this question















      Now, I have two 8bit arrays



      One is 



      A[8] = {1,2,3,4,5,6,7,8}


      Another is 



      B[2] = {1,2}


      What I want to calculate is that: 



      C = A x B = {1,2,3,4,5,6,7,8} x {1, 2, 1, 2, 1, 2, 1, 2} = {1,4,3,8,5,12,7,16}


      How to do this using armv7 simd
      efficiently?






      simd neon armv7




      simd neon armv7






      share|improve this question















      share|improve this question













      share|improve this question




      share|improve this question








      edited Oct 12 at 4:26

























      asked Oct 12 at 4:17









      Y.Zhu

      177




      177
























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          Define B as B[8] = {1,2,1,2,1,2,1,2} and use vld1_u8 and vmul_u8.






          share|improve this answer





















          • How to define B as {1,2,1,2,1,2,1,2} ？Here i need the cross load and the duplication, and that's the point.
            – Y.Zhu
            Nov 12 at 6:00













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          up vote
          0
          down vote













          Define B as B[8] = {1,2,1,2,1,2,1,2} and use vld1_u8 and vmul_u8.






          share|improve this answer





















          • How to define B as {1,2,1,2,1,2,1,2} ？Here i need the cross load and the duplication, and that's the point.
            – Y.Zhu
            Nov 12 at 6:00

















          up vote
          0
          down vote













          Define B as B[8] = {1,2,1,2,1,2,1,2} and use vld1_u8 and vmul_u8.






          share|improve this answer





















          • How to define B as {1,2,1,2,1,2,1,2} ？Here i need the cross load and the duplication, and that's the point.
            – Y.Zhu
            Nov 12 at 6:00















          up vote
          0
          down vote










          up vote
          0
          down vote









          Define B as B[8] = {1,2,1,2,1,2,1,2} and use vld1_u8 and vmul_u8.






          share|improve this answer












          Define B as B[8] = {1,2,1,2,1,2,1,2} and use vld1_u8 and vmul_u8.







          share|improve this answer












          share|improve this answer



          share|improve this answer










          answered Nov 11 at 4:47









          rainhaven

          1403




          1403












          • How to define B as {1,2,1,2,1,2,1,2} ？Here i need the cross load and the duplication, and that's the point.
            – Y.Zhu
            Nov 12 at 6:00




















          • How to define B as {1,2,1,2,1,2,1,2} ？Here i need the cross load and the duplication, and that's the point.
            – Y.Zhu
            Nov 12 at 6:00


















          How to define B as {1,2,1,2,1,2,1,2} ？Here i need the cross load and the duplication, and that's the point.
          – Y.Zhu
          Nov 12 at 6:00






          How to define B as {1,2,1,2,1,2,1,2} ？Here i need the cross load and the duplication, and that's the point.
          – Y.Zhu
          Nov 12 at 6:00




















           

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