Difference between revisions of "What the JVM needs"
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=== types === | === types === | ||
− | * structs, value types | + | * structs (efficient pointerless element selection) |
+ | * value types (no mutability, acmp-identity, id-hashcode, monitorenter) | ||
+ | * immutable arrays = array-like value types |
Revision as of 11:43, 28 July 2010
Contents
Notes from Rich Hickey's workshop
user mode limitations
- please optimize this
- fences
- typestate: now immutable - especially arrays (typically encapsulated in non-writing header, a la java.lang.String)
- Why Tailcalls: as a guarantee, not just an optimization
numbers
- fixnums
- need a uniform entry/exit types (Object => boxing)
- Hacker's delight overflow detection is OK (only for add/sub); need a static method that throws overflow-exception?
storage management
- floating garbage foo(o, o=null); is tailcall a solution?
limits
- 31-bit arrays
- 16-bit instructions
- static data structures (array literals)
types
- structs (efficient pointerless element selection)
- value types (no mutability, acmp-identity, id-hashcode, monitorenter)
- immutable arrays = array-like value types