63 lines
1.7 KiB
ArmAsm
63 lines
1.7 KiB
ArmAsm
##==============================================================================
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##
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## crt0.S
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##
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## IQ2000 startup code
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##
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##==============================================================================
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##
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## Copyright (c) 2000, Cygnus Solutions, A Red Hat Company
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##
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## The authors hereby grant permission to use, copy, modify, distribute,
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## and license this software and its documentation for any purpose, provided
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## that existing copyright notices are retained in all copies and that this
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## notice is included verbatim in any distributions. No written agreement,
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## license, or royalty fee is required for any of the authorized uses.
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## Modifications to this software may be copyrighted by their authors
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## and need not follow the licensing terms described here, provided that
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## the new terms are clearly indicated on the first page of each file where
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## they apply.
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##
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##------------------------------------------------------------------------------
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.file "crt0.S"
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##------------------------------------------------------------------------------
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## Startup code
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.section .text
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.global _start
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_start:
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lui %29,%hi(__stack)
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ori %29,%29,%lo(__stack)
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lui %24,%hi(_edata) # get start of bss
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ori %24,%24,%lo(_edata)
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lui %25,%hi(_end) # get end of bss
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ori %25,%25,%lo(_end)
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beq %24,%25,.L0 # check if end and start are the same
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# do nothing if no bss
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.L1:
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sb %0,0(%24) # clear a byte and bump pointer
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addi %24,%24,1
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bne %24,%25,.L1
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nop
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.L0:
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jal _main # call _main to run ctors/dtors
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nop
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xor %4,%4,%4
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jal main # call main program
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xor %5,%5,%5
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jal exit # all done, no need to return or
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or %4,%0,%2 # exit with main's return value
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.section .data
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.global __dso_handle
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.weak __dso_handle
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__dso_handle:
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.long 0
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