RTEMS CPU Architecture Supplement
RTEMS assumes that arguments are placed in the caller's output registers with the first argument in output register 0 (o0), the second argument in output register 1 (o1), and so forth. Until the callee executes a save instruction, the parameters are still visible in the output registers. After the callee executes a save instruction, the parameters are visible in the corresponding input registers. The following pseudo-code illustrates the typical sequence used to call a RTEMS directive with three (3) arguments:
load third argument into o2 load second argument into o1 load first argument into o0 invoke directive
RTEMS CPU Architecture Supplement
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