RFR (S) 8136500: Integer/Long getChars and stringSize should be more idiomatic
Peter Levart
peter.levart at gmail.com
Tue Nov 24 17:27:57 UTC 2015
On 11/24/2015 06:22 PM, Peter Levart wrote:
>
>
> On 11/24/2015 06:11 PM, Peter Levart wrote:
>>> byte r = (byte)((q * 100 - i) & 0x7F);
>>> // byte allows the compiler to use byte wide addressing
>>> opcodes
>>> // which have smaller footprint and are potentially faster
>>> // .. & 0x7F may additionally save negative bound check
>>> buf[(byte)(--index & 0x7F)] = DigitOnes[r];
>>> buf[(byte)(--index & 0x7F)] = DigitTens[r];
>>
>> ...but index can be large and overflow byte range. Imagine
>> concatenating into a String with target length > 127 ...
>
> .. for addressing DigitOnes and DigitTens it is ok and might be
> faster, as you say.
>
> If DigitOnes and DigitTens are extended for 28 ignored zero slots, it
> may save the upper bound check too.
>
> Regards, Peter
>
I think that the index of code idiomatism has reached the local maximum
and is now falling ... ;-)
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