Why doesn't HotSpot use div machine code?

Christian Thalinger Christian.Thalinger at Sun.COM
Wed Jan 13 01:55:45 PST 2010

On Wed, 2009-12-23 at 22:01 +0100, Ulf Zibis wrote:
> Why doesn't HotSpot use div machine code?
> I guess this would be faster here.

Intel's div/idiv instructions have a very high latency and the latency
even varies with the input values, as you can see in Intels'
Optimization Reference Manual[1] around page C-27.  

Additionally a Java division (idiv) needs special treatment of corner
cases, as you can read in the JVM specification.

[1] http://www.intel.com/Assets/PDF/manual/248966.pdf

-- Christian

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