It turned out that tortoiseGit's diff and merge tools were separate from git.
I succeeded in configuring tortoiseGit with LVMerge and LVDiff.
Although I haven't really succeeded in configuring git with LVMerge and LVDiff, I think it would be better to configure difftool and mergetool than low level diff and merge drivers for LabVIEW.
There are two reasons.
1) If I set up a low level diff driver for LVDiff, git extensions would launch LVDiff whenever I select a file in git extension's commit window, which is very annoying.
2) If I set up a low level merge driver for LVDiff, every "git merg