On Wed, 30 Apr 2025 15:59:05 GMT, fabioromano1 <d...@openjdk.org> wrote:
>> This PR optimizes `BigInteger.pow(int)` method. The primary enhancement in
>> `pow()` is not concerned most on execution time, but rather in memory
>> optimization, because the PR implementation does the "shift of the exponent"
>> squaring the result rather than the base, so the base is not squared like in
>> the current implementation, and this permits to save about half of the
>> memory.
>
> fabioromano1 has updated the pull request incrementally with one additional
> commit since the last revision:
>
> Simplify long power computing
test/micro/org/openjdk/bench/java/math/BigIntegerPow.java line 72:
> 70:
> 71: new Runner(opt).run();
> 72: }
There's no need for these lines.
test/micro/org/openjdk/bench/java/math/BigIntegerPow.java line 117:
> 115: @OperationsPerInvocation(TESTSIZE)
> 116: public void testPowXS(Blackhole bh) {
> 117: for (BigInteger s : xsArray) {
Suggestion:
for (BigInteger xs : xsArray) {
and similarly for the other arrays.
test/micro/org/openjdk/bench/java/math/BigIntegerPow.java line 118:
> 116: public void testPowXS(Blackhole bh) {
> 117: for (BigInteger s : xsArray) {
> 118: bh.consume(s.pow(xsExp));
Suggestion:
bh.consume(s.pow(xsExp & ~0b0111_0101));
bh.consume(s.pow(xsExp));
bh.consume(s.pow(xsExp + 1));
or something similar, just to measure other than "all-ones" exponents as well.
-------------
PR Review Comment: https://git.openjdk.org/jdk/pull/24690#discussion_r2077443258
PR Review Comment: https://git.openjdk.org/jdk/pull/24690#discussion_r2077449324
PR Review Comment: https://git.openjdk.org/jdk/pull/24690#discussion_r2077452722
