On Sun, 30 Apr 2023 06:14:28 GMT, Chen Liang <li...@openjdk.org> wrote:
> Try to intrinsify MethodHandles.arrayConstructor for java.lang, > java.lang.invoke, and java.util types, which InvokerBytecodeGenerator can > refer to directly in a class constant. > > In fact, the performance difference of Array.newInstance and anewarray is > quite negligible per benchmark: > > Benchmark Mode > Cnt Score Error Units > MethodHandlesArrayConstructorCall.baselineConstruct avgt > 5 3.467 ± 0.163 ns/op > MethodHandlesArrayConstructorCall.constantFoldConstruct avgt > 5 3.403 ± 0.070 ns/op > MethodHandlesArrayConstructorCall.constantFoldNonInvocableConstruct avgt > 5 3.445 ± 0.231 ns/op > MethodHandlesArrayConstructorCall.instanceConstruct avgt > 5 4.034 ± 0.168 ns/op > MethodHandlesArrayConstructorCall.instanceNonInvocableConstruct avgt > 5 4.038 ± 0.104 ns/op > MethodHandlesArrayConstructorColdStart.testCreateInvocable ss > 10 1425.991 ± 308.216 us/op > MethodHandlesArrayConstructorColdStart.testCreateNonInvocable ss > 10 1401.480 ± 258.402 us/op > MethodHandlesArrayConstructorColdStart.testCreateObject ss > 10 1213.018 ± 166.522 us/op > MethodHandlesArrayConstructorColdStart.testCreatePrimitive ss > 10 1163.461 ± 178.549 us/op src/java.base/share/classes/java/lang/invoke/MethodHandles.java line 4334: > 4332: MethodHandle ani = > MethodHandleImpl.getConstantHandle(MethodHandleImpl.MH_Array_newInstance). > 4333: bindTo(arrayClass.getComponentType()); > 4334: return ani.asType(ani.type().changeReturnType(arrayClass)); Since `Array.newInstance` is already intrinsified, this patch should probably dropped and the issue be no longer valid. However, one nit I have is that we can convert this `asType` to `viewAsType(..., false)` since `Array.newInstance`'s return type is trusted. ------------- PR Review Comment: https://git.openjdk.org/jdk/pull/13735#discussion_r1181301403
