Hello All:

Since the prefetch instruction have no direct consumers  in the code stream, 
they provide considerable freedom to the 
Instruction scheduler. They are typically assigned lower priorities than most 
of the instructions in the code stream.
This tends to cause all the prefetch instructions to be placed together in the 
final schedule. This causes the performance
Degradations by placing them in clumps rather than evenly spreading the 
prefetch instructions.

The evenly spreading the prefetch instruction gives better speed up ratios as 
compared to be placing in clumps for dirty
Misses.

I am curious to know how the schedulers in the GCC handles the prefetch 
instruction and how the priorities is assigned to
Prefetch instructions in the gcc schedulers so that the prefetch instruction is 
evenly spread.

Please let me know what do you think.

Thanks & Regards
Ajit

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