Bckgrnd2 - JITs and Portability
gPortableh languages e.g., Java
Does not compile directly to CPU native code
Interpretive execution of common bytecodes on VMs
Speed problem i1/10 ` 1/100 vs. optim. native code)
Just-In-Time compiler to the rescue
Rather old idea: Smalltalk, etc.
Compile bytecode into native code at runtime
1/2 ` 1/10 vs. optim. native code
Sun, MS, IBM, Symantec, Fujitsu, etc., vigorously
developing gthe besth Java JIT.