JDK-6537990 : Optimize multibytes NOP generation and loops alignment
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Use '0F 01' NOP instructions.
Avoid generation of several NOPs for loop alignment if possible.
Generate "address" NOPs under the product flag UseAddressNop,
for new Intel cpus the default is true otherwise it is false.
Added few C2 flags to optimize loop alignment padding generation:
MaxLoopPad - default (OptoLoopAlignment-1), for Intel == 11 (max NOP size),
generate padding if it is <= MaxLoopPad.
NumberOfLoopInstrToAlign - default 4, generate padding if it is less then
size of first NumberOfLoopInstrToAlign loop instructions.
Using '0F 01' NOP instruction allow to reduce the number of nop instructions.