RFR: 8306842: Classfile API performance improvements [v5]

[Andrey Turbanov]

On Mon, 15 May 2023 14:48:58 GMT, Adam Sotona <asotona at openjdk.org> wrote:

>> Following improvements implemented:
>> - Switch over `String` replaced with switch single char
>> - Binary search for frames in `StackMapGenerator`
>> - `StackMapGenerator.rawHandlers` with pre-calculated offsets
>> - `ClassEntry` is caching `ClassDesc` symbol
>> - Caching of type symbols in `NameAndTypeEntry` and `MethodTypeEntry`
>> - Caching `MethodTypeDesc` in `MethodInfo` implementations
>> - `StackMapGenerator` and `Utils` delegating to cached `MethodTypeDesc` instead of custom parsing
>> 
>> No API change.
>> 
>> Benchmarks show stack map generation improved by 21% and code generation from symbols improved by 30%.
>> 
>> 
>> Benchmark                     Mode  Cnt       Score       Error  Units
>> GenerateStackMaps.benchmark  thrpt   10  407931.202 ± 13101.023  ops/s
>> RebuildMethodBodies.shared   thrpt    4   10258.597 ±   383.699  ops/s
>> RebuildMethodBodies.unshared thrpt    4    7224.543 ±   256.800  ops/s
>> 
>> 
>> 
>> Benchmark                     Mode  Cnt       Score      Error  Units
>> GenerateStackMaps.benchmark  thrpt   10  495101.110 ± 2389.628  ops/s
>> RebuildMethodBodies.shared    thrpt   4   13380.272 ±  810.113  ops/s
>> RebuildMethodBodies.unshared  thrpt   4    9399.863 ±  557.060  ops/s
>
> Adam Sotona has updated the pull request incrementally with two additional commits since the last revision:
> 
>  - changed LinkedList to ArrayList in RebuildMethodBodies benchmark
>  - added RepeatedModelTraversal JMH benchmark

src/java.base/share/classes/jdk/internal/classfile/impl/StackMapDecoder.java line 85:

> 83:         for(var arg : methodType.parameterList()) {
> 84:             vtis[i++] = switch (arg.descriptorString().charAt(0)) {
> 85:                 case 'I', 'S', 'C' ,'B', 'Z' ->  SimpleVerificationTypeInfo.ITEM_INTEGER;

Suggestion:

                case 'I', 'S', 'C' ,'B', 'Z' -> SimpleVerificationTypeInfo.ITEM_INTEGER;

test/micro/org/openjdk/bench/jdk/classfile/RebuildMethodBodies.java line 58:

> 56:         shared = new ArrayList<>();
> 57:         unshared = new ArrayList<>();
> 58:         Files.walk(FileSystems.getFileSystem(URI.create("jrt:/")).getPath("modules/java.base/java")).forEach(p ->  {

Suggestion:

        Files.walk(FileSystems.getFileSystem(URI.create("jrt:/")).getPath("modules/java.base/java")).forEach(p -> {

test/micro/org/openjdk/bench/jdk/classfile/RepeatedModelTraversal.java line 55:

> 53:     public void setup() throws IOException {
> 54:         models = new LinkedList<>();
> 55:         Files.walk(FileSystems.getFileSystem(URI.create("jrt:/")).getPath("modules/java.base/java/util")).forEach(p ->  {

Suggestion:

        Files.walk(FileSystems.getFileSystem(URI.create("jrt:/")).getPath("modules/java.base/java/util")).forEach(p -> {

-------------

PR Review Comment: https://git.openjdk.org/jdk/pull/13671#discussion_r1194695545
PR Review Comment: https://git.openjdk.org/jdk/pull/13671#discussion_r1194695808
PR Review Comment: https://git.openjdk.org/jdk/pull/13671#discussion_r1194695081