Bug ID: JDK-8262950 Restructure compiler/intrinsics/TestRotate.java for easier compilation

Type: Bug
Component: hotspot
Sub-Component: compiler
Affected Version: 17

Priority: P4
Status: Resolved
Resolution: Fixed

Submitted: 2021-03-03
Updated: 2021-07-15
Resolved: 2021-03-04

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JDK 17
17 b13Fixed

It seems that after JDK-8256438 this test is very slow. See JDK-8262465 for more evidence of this. 
I believe the underlying cause is that main() is way too busy with test cases, so this eventually happens:

$ javac test/hotspot/jtreg/compiler/intrinsics/TestRotate.java
$ java -XX:-TieredCompilation -XX:CompileThreshold=1000 -Xbatch -XX:+PrintCompilation -cp test/hotspot/jtreg compiler.intrinsics.TestRotate
 ...
   6112  112 % !b        compiler.intrinsics.TestRotate::main @ 1494 (3008 bytes)   COMPILE SKIPPED: out of nodes during split (retry at different tier)

So, while the test is intended to test rotate intrinsics, I think it never gets there because compilation bails. And this also makes the test slow. This is tier1 test, and so its performance is somewhat important for developer experience.

This improvement restructures the test to be easier to JIT compile.

Relates :	JDK-8262465 - Very long compilation times and high memory consumption in C2 debug builds
Relates :	JDK-8256438 - AArch64: Implement match rules with ROR shift register value
Relates :	JDK-8252776 - Create regression test for 8252188