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;----------------------------------------------------------------------------------------------
; SpurHandler -- This is the Interrupt handler for IRQ7.  It will be called with each spurious
;                interrupt.  It will also be called for any LPT1 interrupt, so we will need
;                to be careful with this.
;
; Keep in mind that this 'function' does not have a normal entry process or exit process.  We
; need to be particularly careful about saving and restoring EVERYTHING we will touch.
;----------------------------------------------------------------------------------------------

SpurHandler:
                push        rbp                     ; save the interrupted process's frame
                mov.q       rbp,rsp                 ; we want our own frame
                push        rax                     ; yes, we even save rax

;----------------------------------------------------------------------------------------------
; check if it is a spurious interrupt
;----------------------------------------------------------------------------------------------

                mov.q       rax,pic                 ; get the pic interface structure
                mov.q       rax,[rax+PIC.readISR]   ; get the ReadISR fucntion address
                call        rax                     ; do we have an interrupt
                test.q      rax,0x80                ; test bit 7
                jz          .eoi                    ; we have a real interrupt; ack it

                mov.q       rax,spurCount           ; get the counter address
                inc         qword [rax]             ; increment the count

%ifndef DISABLE_DBG_CONSOLE
                mov.q       rax,spurIntRcvd         ; get the text address
                push        rax                     ; put it on the stack
                call        DbgConsolePutString     ; write it to the console
                add.q       rsp,8                   ; clean up the stack
%endif
                jmp         .out                    ; go exit

.eoi:           mov.q       rax,pic                 ; get the pic interface structure
                mov.q       rax,[rax+PIC.eoi]       ; get the EOI fucntion address
                push        0x07                    ; we need to ack IRQ7
                call        rax                     ; do we have an interrupt

.out:           pop         rax                     ; restore rax
                pop         rbp                     ; restore rbp
                iretq

;==============================================================================================

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Global Descriptor Table (base=0xffffa000000b8060, limit=55):
GDT[0x00]=??? descriptor hi=0x00000000, lo=0x00000000
GDT[0x01]=Code segment, base=0x00000000, limit=0x00000fff, Execute/Read, Non-Conforming, Accessed, 64-bit
GDT[0x02]=Data segment, base=0x00000000, limit=0x00000fff, Read/Write, Accessed
GDT[0x03]=Code segment, base=0x00000000, limit=0x00000fff, Execute/Read, Non-Conforming, 64-bit
GDT[0x04]=Data segment, base=0x00000000, limit=0x00000fff, Read/Write
GDT[0x05]=32-Bit TSS (Busy) at 0xfff00000, length 0x00067
GDT[0x06]=??? descriptor hi=0x00000000, lo=0xffffff7f

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0xffffa000000b8060 <bogus+       0>:	0x00000000	0x00000000	0x00000000	0x00a09b00
0xffffa000000b8070 <bogus+      16>:	0x00000000	0x00809300	0x00000000	0x00a0fa00
0xffffa000000b8080 <bogus+      32>:	0x00000000	0x0080f200	0x00000067	0xff808bf0
0xffffa000000b8090 <bogus+      48>:	0xffffff7f	0x00000000