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[/] [or1k/] [trunk/] [newlib/] [libgloss/] [sparc/] [crt0.s] - Rev 1775
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! Copyright (c) 1995 Cygnus Support ! ! The authors hereby grant permission to use, copy, modify, distribute, ! and license this software and its documentation for any purpose, provided ! that existing copyright notices are retained in all copies and that this ! notice is included verbatim in any distributions. No written agreement, ! license, or royalty fee is required for any of the authorized uses. ! Modifications to this software may be copyrighted by their authors ! and need not follow the licensing terms described here, provided that ! the new terms are clearly indicated on the first page of each file where ! they apply. ! ! C startup code for the Fujitsu SPARClite demo board .text .align 8 win_ovf_trap: sethi %hi(win_ovf), %l3 jmpl %lo(win_ovf)+%l3, %g0 mov %wim, %l0 nop win_unf_trap: sethi %hi(win_unf), %l3 jmpl %lo(win_unf)+%l3, %g0 mov %wim, %l0 nop no_fpu_trap: ! Come here when no fpu exists. This just skips the jmpl %l2, %g0 ! offending instruction. rett %l2+4 .globl start .globl _start start: _start: ! First, copy prom & trap vectors to sram set 0x30000000, %l0 set 0xfff8, %l1 tst %l1 ! Set condition codes copyloop: ldd [%l1], %l2 std %l2, [%l0 + %l1] bg copyloop deccc 8, %l1 set 0x30000000, %l0 ! Base of new trap vector mov %l0, %tbr ! Install the new tbr set win_ovf_trap, %l1 ! Setup window overflow trap ldd [%l1], %l2 std %l2, [%l0 + 5 * 16] ldd [%l1 + 8], %l2 std %l2, [%l0 + 5 * 16 + 8] set win_unf_trap, %l1 ! Setup window underflow trap ldd [%l1], %l2 std %l2, [%l0 + 6 * 16] ldd [%l1 + 8], %l2 std %l2, [%l0 + 6 * 16 + 8] ! Try enabling the FPU by setting EF. If that causes a trap, then we probably ! don't have an FPU. ldd [%l0 + 2 * 16], %l4 ! Save original trap routine set no_fpu_trap, %l1 ! Install new one ldd [%l1], %l2 std %l2, [%l0 + 2 * 16] mov %psr, %l0 sethi %hi(0x1000), %l1 bset %l1, %l0 ! mov %l0, %psr std %l4, [2 * 16] ! Restore original trap routine call _main nop
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