RFR(S) 8029302: Performance regression in Math.pow intrinsic

[David Chase]

On 2014-04-18, at 5:36 PM, Vladimir Kozlov <vladimir.kozlov at oracle.com> wrote:

> On 4/17/14 11:04 PM, Christian Thalinger wrote:
>> 
>> On Apr 17, 2014, at 3:21 PM, David Chase <david.r.chase at oracle.com> wrote:
>> 
>>> You are right, what was I thinking?
>>> Does the intrinsic jump directly on Math.pow, or on some internal method that would make this an easy library fix?
>> 
>> Look at my last comment in the bug; we intrinsify Math.pow directly.  So we would need to introduce another method we intrinsify so the Java code stays.
> 
> We asked about this and the answer was: no, changes should be in VM.
> I updated the bug report.

Is there any way we can push back on this?

Putting the changes in the VM is more costly in almost every way.
More chance of bugs, more debt to port to new compilers or new architectures,
less transparent behavior, more lines of code.

David

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