mirror of https://gitee.com/openkylin/qemu.git
65 lines
1.6 KiB
C
65 lines
1.6 KiB
C
/*
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* MIPS o32 Linux syscall example
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*
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* http://www.linux-mips.org/wiki/RISC/os
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* http://www.linux-mips.org/wiki/MIPSABIHistory
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* http://www.linux.com/howtos/Assembly-HOWTO/mips.shtml
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*
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* mipsel-linux-gcc -nostdlib -mno-abicalls -fno-PIC -mabi=32 \
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* -O2 -static -o hello-mips hello-mips.c
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*
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*/
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#define __NR_SYSCALL_BASE 4000
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#define __NR_exit (__NR_SYSCALL_BASE+ 1)
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#define __NR_write (__NR_SYSCALL_BASE+ 4)
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static inline void exit1(int status)
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{
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register unsigned long __a0 asm("$4") = (unsigned long) status;
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__asm__ __volatile__ (
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" .set push \n"
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" .set noreorder \n"
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" li $2, %0 \n"
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" syscall \n"
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" .set pop "
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:
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: "i" (__NR_exit), "r" (__a0)
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: "$2", "$8", "$9", "$10", "$11", "$12", "$13", "$14", "$15", "$24",
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"memory");
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}
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static inline int write(int fd, const char *buf, int len)
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{
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register unsigned long __a0 asm("$4") = (unsigned long) fd;
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register unsigned long __a1 asm("$5") = (unsigned long) buf;
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register unsigned long __a2 asm("$6") = (unsigned long) len;
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register unsigned long __a3 asm("$7");
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unsigned long __v0;
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__asm__ __volatile__ (
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" .set push \n"
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" .set noreorder \n"
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" li $2, %2 \n"
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" syscall \n"
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" move %0, $2 \n"
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" .set pop "
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: "=r" (__v0), "=r" (__a3)
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: "i" (__NR_write), "r" (__a0), "r" (__a1), "r" (__a2)
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: "$2", "$8", "$9", "$10", "$11", "$12", "$13", "$14", "$15", "$24",
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"memory");
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/* if (__a3 == 0) */
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return (int) __v0;
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/*
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errno = __v0;
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return -1;
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*/
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}
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void __start(void)
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{
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write (1, "Hello, World!\n", 14);
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exit1 (42);
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}
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