57 lines
837 B
ArmAsm
57 lines
837 B
ArmAsm
;;;
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;;;
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;;; ctt0.S
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;;;
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;;; \file
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;;; C runtime startup routine
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;;;
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;;; \author
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;;; Takahide Matsutsuka <markn@markn.org>
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;;;
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.module crt0
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.globl _main
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.area _HEADER (ABS)
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.org 0
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jp init
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;; Ordering of segments for the linker.
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.area _HOME
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.area _CODE
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.area _GSINIT
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.area _GSFINAL
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.area _DATA
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.area _DATAFINAL
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.area _BSS
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.area _HEAP
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.area _CODE
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init::
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;; Clear global variables
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ld hl, #_datastart
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ld bc, #_dataend
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_clear_loop:
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ld a, h
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sub b
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jr nz, _clear_next
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ld a, l
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sub c
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jr z, _clear_exit
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_clear_next:
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ld (hl), #0
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inc hl
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jr _clear_loop
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_clear_exit:
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;; Initialize global variables
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call gsinit
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jp _main
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.area _GSINIT
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gsinit::
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.area _GSFINAL
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ret
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.area _DATA
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_datastart::
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.area _DATAFINAL
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_dataend::
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