JDK-8331576 : C2 SuperWord: Unsafe access with long address that is a CastX2P does not vectorize
  • Type: Enhancement
  • Component: hotspot
  • Sub-Component: compiler
  • Affected Version: 23
  • Priority: P4
  • Status: Open
  • Resolution: Unresolved
  • Submitted: 2024-05-02
  • Updated: 2025-01-07
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Other
tbdUnresolved
Related Reports
Relates :  
JDK-8330991 - C2 SuperWord: refactor VPointer
Relates :  
JDK-8343685 - C2 SuperWord: refactor VPointer with MemPointer
Description
Attached file, here the commandline:

The issue is that the VPointer wants the address to be a AddP. But in this case, it directly gets a CastX2P, which it does currently not parse through.

./java --add-modules java.base --add-exports java.base/jdk.internal.misc=ALL-UNNAMED --add-exports java.base/jdk.internal.util=ALL-UNNAMED -XX:CompileCommand=compileonly,Test*::* -XX:CompileCommand=printcompilation,TestMemorySegment::* -XX:CompileCommand=TraceAutoVectorization,Test*::*,SW_REJECTIONS,PRECONDITIONS,POINTERS -XX:+TraceNewVectors -XX:+TraceLoopOpts -Xbatch TestUnsafeAllocateLongAdr.java