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<div>I am currently trying to use LLVM (version 3.2) to generate code for a cluster where each node in the cluster will be running a 64-bit X86 chip, but *<b>not</b>* necessarily the same version of the X86 chip throughout the cluster. I am specifying that
I want Position-Independent Code produced because the generated machine code may get moved (before it is executed) to a different logical address that where it is built by the JIT Compiler. Furthermore, the generated machine code may get moved to a different
node in the cluster before it is executed.</div>
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<div>Yes, I know that version 3.2 is not the latest and, yes, I know that I should be using MCJIT rather than JIT, but from my reading thus far on version 3.4 and on MCJIT, I don’t think it will affect the answer to my question. If I am wrong, I would be
happy to be corrected. [When I started the project, version 3.2 was the latest available (and JIT looked easier to use) … and I haven’t yet had sufficient reason to upgrade.]</div>
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<div>I have been telling the JIT compiler to use the Default level of code optimization. My problem is that I believe I have found that the JIT compiler is doing chip-specific code optimization to make the code run as fast as possible for the chip which is
running the compiler. However, the generated machine code may get moved to a different version of the chip when the code gets moved to a different node in the cluster. I believe I can get generic X86 code generated by using an optimization level of NONE,
but that may hurt performance too much. </div>
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<div>So, my question is: Is there an option (using either JIT or MCJIT) where I can specify that I want the generated code to be generic enough to run on any version of a 64-bit X86 chip … without turning off all optimization?</div>
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<div>Thanks,</div>
<div>Jim Capps</div>
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