Optimizing branch condition expressions in a JIT compiler

1. A computer system comprising:

a processor;

a memory system;

an operating system; and

a Java virtual machine including:

a just in time (JIT) Java compiler including at least one optimizer, each one of the at least one optimizer including:

logic for recognizing a pattern in a received Java byte code, wherein the pattern includes a conditional branch instruction;

logic for optimizing the recognized pattern to produce optimized native code including:

logic for analyzing the conditional branch instruction and a subsequent set of instructions;

logic for replacing the conditional branch instruction with a conditional instruction; and

logic for compiling the conditional instruction in native code; and

logic for outputting optimized native code.

2. The system of claim 1 , wherein the least one optimizer is at least partially coded in logic circuitry.

3. The system of claim 1 , wherein the least one optimizer is at least partially coded in software.

4. A computer system comprising:

a processor;

a memory system;

an operating system; and

a Java virtual machine including:

a just in time (JIT) Java compiler including at least one optimizer that is at least partially coded in logic circuitry, each one of the at least one optimizer including:

logic for recognizing a pattern in a received Java byte code that includes a branching instruction that can be optimized in a native code conditional instruction;

logic for optimizing the recognized pattern to produce optimized native code including:

logic for analyzing the conditional branch instruction and a subsequent set of instructions;

logic for replacing the conditional branch instruction with a conditional instruction; and

logic for compiling the conditional instruction in native code; and

logic for outputting optimized native code to a native processing platform.

5. A method of optimizing a Java byte code comprising:

receiving the Java byte code in a JIT compiler;

analyzing the Java byte code to determine if the Java byte code includes one of a plurality of preselected patterns wherein the pattern includes a conditional branch instruction;

producing an optimized native code from the Java byte code including one of the plurality of preselected patterns including:

analyzing the conditional branch instruction and a subsequent set of instructions;

replacing the conditional branch instruction with a conditional instruction; and

compiling the conditional instruction in native code; and

outputting the optimized native code.

6. The method of claim 5 , wherein the JT compiler is included in a Java virtual machine.

7. The method of claim 5 , wherein analyzing the Java byte code to determine if the Java byte code includes one of the plurality of preselected patterns includes recognizing a trigger-type instruction.

8. The method of claim 7 , wherein the trigger-type instruction is a forward branching instruction.

9. The method of claim 7 , wherein the plurality of preselected patterns are encoded in the JIT compiler.

10. The method of claim 7 , wherein if the trigger-type instruction is recognized, further comprising examining a number of subsequent instructions from the Java byte code.

11. The method of claim 10 , wherein the number of subsequent instructions to be examined is determined by the recognized trigger-type instruction.

12. The method of claim 5 , wherein outputting the optimized native code includes outputting the optimized native code to a processor platform.