Optimize deref methods with tableswitch pattern for JVM performance #94
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- arrayDeref(): Move ARRAYREFERENCE to if-check before switch, cases 0-11 in order - hashDeref(): Move HASHREFERENCE to if-check before switch, cases 0-11 in order - hashDerefNonStrict(): Move HASHREFERENCE to if-check before switch, cases 0-11 in order - arrayDerefNonStrict(): Move ARRAYREFERENCE to if-check before switch, cases 0-11 in order This optimization ensures the JVM generates efficient tableswitch bytecode for the contiguous integer cases 0-11 (INTEGER through FORMAT), while keeping the most common reference type checks as fast if-statements.
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Summary
Optimizes the four dereferencing methods in RuntimeScalar.java to leverage JVM tableswitch bytecode for better performance.
Changes
Rationale
The JVM generates efficient tableswitch bytecode for contiguous integer cases (0-11: INTEGER through FORMAT). By moving the high-valued reference types (ARRAYREFERENCE/HASHREFERENCE with REFERENCE_BIT set) to an if-statement before the switch, we preserve this optimization while keeping the most common case as a fast path.