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Vectorizing Compiler

1. Fortran 77 DO Loop

   • DO I=1, N
       D(I) = A(I)*B+C(I)
     ENDDO
     

2. Vectorization

   • D(1:N) = A(1:N)*B+C(1:N)
     

3. Strip mining

   • DO I=1, N/128
       D(I:I+127) = A(I:I+127)*B + C(I:I+127)
     ENDDO
     IF ((N.MOD.128).NEQ.0) 
       A((N/128)*128+1:N) = ...
     ENDIF
     

4. Code generation

   • V0 <- V0*B
     ...
     

Related techniques for parallelizing compiler!