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91 lines
1.9 KiB
ArmAsm
91 lines
1.9 KiB
ArmAsm
;
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; Startup code for cc65 (Oric version)
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;
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; By Debrune Jérôme <jede@oric.org> and Ullrich von Bassewitz <uz@cc65.org>
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;
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.export _exit
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.export __STARTUP__ : absolute = 1 ; Mark as startup
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.import initlib, donelib
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.import callmain, zerobss
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.import __MAIN_START__, __MAIN_SIZE__
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.include "zeropage.inc"
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; ------------------------------------------------------------------------
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; Place the startup code in a special segment.
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.segment "STARTUP"
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tsx
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stx spsave ; Save system stk ptr
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; Save space by putting some of the start-up code in a segment
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; that will be re-used.
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jsr init
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; Clear the BSS variables (after the constructors have been run).
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jsr zerobss
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; Push the command-line arguments; and, call main().
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jsr callmain
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; Call the module destructors. This is also the exit() entry.
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_exit: jsr donelib
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; Restore the system stuff.
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ldx spsave
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txs
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; Copy back the zero-page stuff.
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ldx #zpspace - 1
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L2: lda zpsave,x
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sta sp,x
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dex
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bpl L2
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; Back to BASIC.
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rts
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; ------------------------------------------------------------------------
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; Put this code in a place that will be re-used by BSS, the heap,
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; and the C stack.
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.segment "ONCE"
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; Save the zero-page area that we're about to use.
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init: ldx #zpspace - 1
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L1: lda sp,x
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sta zpsave,x
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dex
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bpl L1
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; Set up the C stack.
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lda #<(__MAIN_START__ + __MAIN_SIZE__)
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ldx #>(__MAIN_START__ + __MAIN_SIZE__)
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sta sp
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stx sp+1 ; Set argument stack ptr
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; Call the module constructors.
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jmp initlib
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; ------------------------------------------------------------------------
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.segment "INIT"
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spsave: .res 1
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stsave: .res 1
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zpsave: .res zpspace
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