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[RFC][LIBGCC][0 of 2] 64 bit divide implementation for processor without hw divide instruction


Hi All,

This RFC patch series implements a simple align divisor shift dividend
method for 64bit divide  and enables for ARMv7-a.

This algorithm runs (K+1) times where K is the number of bits divisor is
shifted to align. I have done repeated divides and found that this
implementation performs better for processor without hw divide instruction.

On a chromebook, when K is large (close to 64) this performs on an
average ~10% faster. When K is small (8 to 24), it performs about ~100%
faster on an average.

Regression tested on arm-none-linux-gnueabi with no issues.

OK?

Thanks,
Kugan


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