slightly off-topic here, floating point operation is even much much more harder inside kernel, mainly because of trapping mechinism. In fact most OS either do not support floating point operation inside kernel or just turn that option off by default. But the good thing is you do not really need floating point operations inside kernel, but when you do and needs to modify your kenrel code to achieve that, it is extremely implementationally intensive and hard to made one (and the runtime cost is expensive also).
Hm, in our kernel, when we need to do floating point, we just set a flag on the thread control block which preserves the floating registers on context switch, and then do our floating point operations. Maybe there is some API abstraction hiding the messy details :).
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slightly off-topic here, floating point operation is even much much more harder inside kernel, mainly because of trapping mechinism. In fact most OS either do not support floating point operation inside kernel or just turn that option off by default. But the good thing is you do not really need floating point operations inside kernel, but when you do and needs to modify your kenrel code to achieve that, it is extremely implementationally intensive and hard to made one (and the runtime cost is expensive also).
Hm, in our kernel, when we need to do floating point, we just set a flag on the thread control block which preserves the floating registers on context switch, and then do our floating point operations. Maybe there is some API abstraction hiding the messy details :).