How does PlatformIO generate. map files?

How does platformIO generate. map files, just like compiling them in KEIL can generate. map files. Do you want to change anything in the extra_script file?

Generating .map files is done by the compiler, GCC. You configure PlatformIO to tell GCC to do that via build_flags. See Generate a .map file - #8 by Krishna_Chaitanya