PUF Instruction

Synopsis

PUF <routineLevel> <returnLabel>

Description

The PUF instruction pushes the stack frame for a routine. This is in contrast to the PPF instruction which pushes the stack frame for a call made through a routine pointer.

Warning

The PUF instruction pushes the stack frame base pointer onto the CPU stack. It is very important to Call the ASF instruction after pushing the routine arguments onto the runtime stack. The ASF instruction pops the stack frame base pointer back off the CPU stack and sets the stack frame pointer.

RoutineLevel Operand

This is the scope level of the routine. It is used to calculate the static link portion of the stack frame. The stack link points to the containing routine's stack frame.

ReturnLabel Operand

This is the label for the caller's return point. This is where execution will resume when the routine completes.