Re: How to Make F77 Program Faster (g95 compiler) ??

On Nov 13, 7:46 am, Chip Coldwell <coldw...@xxxxxxxxxxxxx> wrote:

The latest (version 10) Intel Fortran compilers do auto-vectorization
of loops by default (where possible). I found that merely by
upgrading from version 9 to version 10 with no other changes my code
sped up by about 14%.

This is true of the 64-bit compiler only as it now assumes SSE2
instructions are available. The 32-bit compiler, at present, does not
do this. There, use the appropriate /Qx switch for your processor
type (/QxW or "higher") in order to enable vectorization.

Steve

.

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