VFPSupport_FastAPI
VFPSupport
» SWI Calls
» VFPSupport_FastAPI
VFPSupport_FastAPI
(SWI &58EC5)
| Entry | |
|---|---|
| - | |
| Exit | |
|---|---|
| R0 | Workspace pointer to pass in R12 to all routines |
| R1 | CheckContext function pointer |
| R2 | CreateContext function pointer |
| R3 | DestroyContext function pointer |
| R4 | ChangeContext function pointer |
| All other registers preserved | |
Use
This call allows you to gain direct access to the most commonly used SWIs, to allow speed-critical systems to avoid the overhead of the kernel SWI despatcher.
Notes
When calling the above functions, the following rules apply:
- The processor must be in a privileged mode
- R14_svc must be corruptible (i.e. if in an interrupt handler, you must have previously saved it)
- R12 must contain the given workspace pointer (R0)
Other than the above, the functions behave exactly like their SWI counterparts.
See also
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