![]() Number of elements in the evaluation stack. regs = print register contents (not implemented).stack = print stack contents (currently only works if you set -VirtualizePerformance=IndexedStack).args = print instruction names and arguments.Insert tracing code to show the stack and the virtual instructions executing. CacheTop = Store the top of stack in a register.Ĭlean up after superoperator generation by optimizing the body of the generated function.AddressSizeLong = Assume addresses for accessing instruction handlers fit in a long.AddressSizeInt = Assume addresses for accessing instruction handlers fit in an int.AddressSizeShort = Assume addresses for accessing instruction handlers fit in a short.PointerStack = Use pointer operations to access stack elements.IndexedStack = Use array indexing to access stack elements.A comma-separated list of the options below. IndexedStack, PointerStack, AddressSizeShort, AddressSizeInt, AddressSizeLong, CacheTop But this still isn’t the end of the story: so far the _hookBIOS function is being called when we press a key on the keyboard, which in turn calls the interrupt service routines that would have normally been called.Generate shorter identifiers to produce interpreters suitable for publication. The _hookBIOS function thus effectively calls the 0x9th and 0x16th ISR routine as well as saves the pressed key to the _buffer memory region. This effectively saves the pressed keys to the memory array located at the _buffer variable, increasing the index into the array by one each key press. Whenever there’s a key to be saved, it is saved in the appropriate array element (denoted by the _index variable) and the _index variable is also increased by 1. At that point we’re storing the pointer to variable _buffer into register BX as a base pointer for the array and the _index variable as an index into the array. But if there is a key in the system’s buffer, we’re continuing with the “LEA BX,_buffer” instruction. If it isn’t, the jump is taken and we’re terminating the function by restoring the register values, re-enabling the Interrupt Flag IF and returning to the calling function. The instruction “jz _hb_Exit” checks whether there’s some key in the system’s buffer. Then we’re using the CLI instruction to clear the Interrupt Flag (IF flag) in the EFLAGS register and storing some register values on the stack. ![]()
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