Hi, A prior email sent out a request for review of the Vector API in preparation for JEP 338: Vector API (Incubator) [1] to be proposed for target:
https://mail.openjdk.java.net/pipermail/core-libs-dev/2020-March/065345.html <https://mail.openjdk.java.net/pipermail/core-libs-dev/2020-March/065345.html> This email expands the review of the API to the Java implementation and Java tests: http://cr.openjdk.java.net/~psandoz/panama/JDK-8223347-vector-api-integration-java/jdk_src_webrev/webrev/ <http://cr.openjdk.java.net/~psandoz/panama/JDK-8223347-vector-api-integration-java/jdk_src_webrev/webrev/> http://cr.openjdk.java.net/~psandoz/panama/JDK-8223347-vector-api-integration-java/jdk_test_webrev/webrev/ <http://cr.openjdk.java.net/~psandoz/panama/JDK-8223347-vector-api-integration-java/jdk_test_webrev/webrev/> (Further emails will sent for review of general HotSpot changes CPU architecture specific HotSpot changes, x64 and aarch64, and performance tests. For an early peek see the links in the description of JDK-8223347.) — The Vector API provides - the public Vector class with vector operations common to all supported primitive types - public primitive specializations, such as IntVector, with common operations associated with the primitive type - internal concrete specializations for the vector size, such as Int256Vector, for a vector holding 8 ints. Operations generally defer to one of approximately 20 vector intrinsics. Some operations may be composed of other operations. Explicit casts are performed by vector operations to ensure vectors arguments are of the required shape (bit size) and element type. A vector intrinsic is an internal low-level vector operation. The last argument to the intrinsic is fall back behavior in Java, implementing the scalar operation over the number of elements held by the vector. Thus, If the intrinsic is not supported in C2 for the other arguments then the Java implementation is executed (the Java implementation is always executed when running in the interpreter or for C1). The public primitive specializations and the internal concrete implementations are generated from SSP template files, X-Vector.java.template and X-VectorBits.java.template respectively. Overall the implementation approach is quite formulaic and rather repetitive. Once you grok the pattern It should be easier to review if a little laborious. Unit tests are auto-generated by composing templates for each operation into an SSP template file which is then used to generate unit test files for each concrete vector class. The tests are quite extensive and have found many a HotSpot issue in development across a wide range of platforms. Paul. [1] https://bugs.openjdk.java.net/browse/JDK-8201271 <https://bugs.openjdk.java.net/browse/JDK-8201271>
