'codegen' is an alias for all LIR transformations used in Jitrino.OPT compiler
Read 'Jitrino Pipeline Management Framework' document to learn more about aliases
Example of 'codegen' alias value for IA32 'server' configuration:
-XX:jit.SD2_OPT.path.codegen=lock_method,bbp,btr,gcpoints,cafl,dce1,i8l,api_magic,\ light_jni-,early_prop,peephole,itrace-,native,cg_fastArrayFill,constraints,dce2,regalloc,spillgen,copy,\ i586,layout,rce+,stack,break-,iprof-,peephole,emitter!,si_insts,gcmap,info,unlock_method