Optimizing symbol table lookups in platform-independent virtual machines

A method for increasing performance of code executing on a virtual machine, comprising:

• receiving a request to resolve an entry in a symbol table associated with a class, wherein resolving the entry requires at least one lookup in the symbol table;
• determining if the entry has previously been resolved;
• if the entry has been previously resolved, returning a pointer to a structure associated with the entry, which was returned during a previous resolution of the entry;
• and
• if the entry has not been previously resolved, resolving the entry through at least one lookup to the symbol table to produce a pointer to the structure, and replacing the entry with the pointer, wherein replacing the entry with the pointer does not require any additional memory.

A computer readable storage medium storing instructions that when executed by a computer cause the computer to perform a method for increasing performance of code executing on a virtual machine, comprising:

• receiving a request to resolve an entry in a constant pool within a class file for a class, wherein resolving the entry requires at least one lookup in the constant pool;
• determining if the entry has previously been resolved;
• if the entry has been previously resolved, returning a pointer to a structure associated with the entry, which was returned during a previous resolution of the entry;
• and
• if the entry has not been previously resolved, resolving the entry through at least one lookup in the constant pool to produce a pointer to the structure, and
• replacing the entry with the pointer, wherein replacing the entry with the pointer does not require any additional memory.

An apparatus for increasing performance of code executing on a virtual machine, comprising:

• a lookup mechanism that looks up an entry in a constant pool within a class file for a class, wherein resolving the entry may require at least one lookup in the constant pool;
• a status indicator, associated with the entry, which indicates if the entry has previously been resolved;
• a bypassing mechanism, that returns a pointer to a structure associated with the entry if the entry has been previously resolved;
• and
• a resolution mechanism that resolves the entry, if the entry has not been previously resolved, through at least one lookup to the constant pool to produce a pointer to the structure, and that replaces the entry with the pointer, wherein replacing the entry with the pointer does not require any additional memory.

An apparatus for increasing performance of code executing on a virtual machine, comprising:

• a lookup means, for looking up an entry in a constant pool within a class file for a class, wherein resolving the entry may require at least one lookup in the constant pool;
• a status indicator means, associated with the entry, for indicating if the entry has previously been resolved;
• a bypassing means for bypassing the lookup to the entry by returning a pointer to a structure associated with the entry if the entry has been previously resolved;
• and
• a resolution means, for resolving the entry, if the entry has not been previously resolved, through at least one lookup to the constant pool to produce a pointer to the structure, and replacing the entry with the pointer, wherein replacing the entry with the pointer does not require any additional memory.