search for: classsify

...same > thing. The second form is the one that appears to work with the ABI on > linux, and the first one not. > > What is the reason for the difference? If you pass a struct directly, the LLVM target will just see an exploded list of the basic types (e.g. i8, i8, i32, ...) and have to classsify them individually. This is usually too simplistic to model a real C ABI, so it's not used much. But LLVM does have to give it some meaning because it's still a legitimate IR function. The result is that you tend to get the arguments out again if everything is consistent, but where they actu...

There appears to be a difference between passing by value:     call void @foo(%some_struct %v) And using the `byval` attribute on a pointer:     call void @foo(%some_struct* byval %v) They are not compatible with each other yet logically do the same thing.  The second form is the one that appears to work with the ABI on linux, and the first one not. What is the reason for the difference? --

...nd form is the one that appears to work with the ABI on >> linux, and the first one not. >> >> What is the reason for the difference? > If you pass a struct directly, the LLVM target will just see an > exploded list of the basic types (e.g. i8, i8, i32, ...) and have to > classsify them individually. This is usually too simplistic to model a > real C ABI, so it's not used much. But LLVM does have to give it some > meaning because it's still a legitimate IR function. The result is > that you tend to get the arguments out again if everything is > consistent,...