Intel® Fortran Compiler Classic and Intel® Fortran Compiler Developer Guide and Reference
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falign-loops, Qalign-loops
Aligns loops to a power-of-two byte boundary. This feature is only available for ifort.
Syntax
Linux:  |  
      -falign-loops[=n] -fno-align-loops  |  
     
Windows:  |  
      /Qalign-loops[:n] /Qalign-loops-  |  
     
Arguments
n  |  
      Is the optional number of bytes for the minimum alignment boundary. It must be a power of 2 between 1 and 4096, such as 1, 2, 4, 8, 16, 32, 64, 128, and so on. If you specify 1 for n, no alignment is performed; this is the same as specifying the negative form of the option. If you do not specify n, the default alignment is 16 bytes.  |  
     
Default
-fno-align-loops or /Qalign-loops-  |  
      No special loop alignment is performed.  |  
     
Description
This option aligns loops to a power-of-two boundary. This alignment may improve performance.
It can be affected by the directives CODE_ALIGN and ATTRIBUTES CODE_ALIGN.
If code is compiled with the -falign-loops=m (Linux*) or /Qalign-loops:m (Windows*) option and a CODE_ALIGN:n directive precedes a loop, the loop is aligned on a MAX (m, n) byte boundary. If a procedure has the CODE_ALIGN:k attribute and a CODE_ALIGN:n directive precedes a loop, then both the procedure and the loop are aligned on a MAX (k, n) byte boundary.
IDE Equivalent
Alternate Options
None
Example
Consider the following code fragment in file test_align_loops.f90:
DO J = 1, N
…
END DO 
   Compiling test_align_loops.f90 with the -falign-loops (Linux) or /Qalign-loops (Windows) compiler option aligns the code that begins the DO J loop on a (default) 16-byte boundary. If you do not specify this compiler option, the alignment of the loop is implementation-dependent and may change from compilation to compilation.