@mournfulwatcher Not exactly 7 to 4 but more like 7.30 to 4.30. A couple of my friends in government worked with that schedule. They go from their house at 6.15 and arrived by 7 am since office in KL. My company (MNC) also have this policy.
Speaking from experience, this is based on the company, some company does have flexi hours, which meant you may come like 7 to 10 am and finish 8 hours of work (excluding lunch hour) and then go back. Not all companies have this, depends on your company policy and whether it is stated in your contract.
You can also double check with HR if they have this policy in place.
Don't forget to check with your boss as well, some positions work schedule may be different, for example, a buddy of mine in procurement will come by 9 am since his work needs to deal with information from others and most people aren't around by 7 am for him to start working.