[userbinator]

Compilers were stupid, and that's how we ended up with this constant overhead of inefficiency long after they could've done better; it's only within the last decade or so that "custom calling conventions" started being even considered.

[almostgotcaught]

Calling conventions have no more to do with dumb or smart compilers than driving on the left-hand side of the road has to do with dumb or smart urban planners.

[userbinator]

Of course they do. An Asm programmer will naturally use the appropriate registers to minimise data movement (see also: PC BIOS interface - no stupid stack shit) depending on the circumstances, a stupid compiler will just push everything on the stack. A more intelligent compiler will behave more like the human programmer and decide how to pass parameters and save or restore registers on a case-by-case basis.