There is no specific command to retain the log files every time you recompile each design phase.
As a workaround, the user can use the "file copy" tcl command after each design phase to copy the logs to a different folder from each design phase and add a name revision on each file.
Here is an example script:
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set rev [clock format [clock seconds] -format {%Y%m%d_%H%M%S}]
#open radiant project
prj_open "C:/Users/jmanguba/counter/counter.rdf"
#run synthesis
prj_run_synthesis
#copy the synthesis log to a different folder named "revision" and the name of the synthesis log will be changed to synthesis_[the current date and time it was copied].log
file copy "C:/Users/jmanguba/counter/impl1/synthesis.log" C:/Users/jmanguba/counter/revisions/synthesis_$rev.log
#run
Map
prj_run_map
#copy the map report to a different folder named "revision" and the name of the map report will be changed to counter_impl1_[the current date and time it was copied].mrp
#Note, the output name of each report file is usually the ["project name"_"implementation name"] for MAP, PAR and Bitgen
file copy C:/Users/jmanguba/counter/impl1/counter_impl1.mrp C:/Users/jmanguba/counter/revisions/counter_impl1_$rev.mrp
#run PAR
prj_run_par
#copy the par report to a different folder named "revision" and the name of the par report will be changed to counter_impl1_[the current date and time it was copied].par
file copy C:/Users/jmanguba/counter/impl1/counter_impl1.par C:/Users/jmanguba/counter/revisions/counter_impl1_$rev.par
#run Bitgen
prj_run_bitstream
#copy the bitstream generation report to a different folder named "revision" and the name of the par report will be changed to counter_impl1_[the current date and time it was copied].bgn
file copy C:/Users/jmanguba/counter/impl1/counter_impl1.bgn C:/Users/jmanguba/counter/revisions/counter_impl1_$rev.bgn
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