This shell snippet counts all lines in all .php files (in and beneath the current path ".") that are non-blank and not comments (yes, it also discards multiline comments).
find . -name '*.php' | xargs cat | sed -re ':top /\/\*.*\*\// { s/\/\*.*\*\///g ; t top }; /\/\*/ { N ; b top }' | awk '$0 !~ /^[\t[:space:]]*($|(\/\/)|(#))/' | wc -l