LXR qemu/tests/tcg/hello-mips.c

   1/*
   2* MIPS o32 Linux syscall example
   3*
   4* http://www.linux-mips.org/wiki/RISC/os
   5* http://www.linux-mips.org/wiki/MIPSABIHistory
   6* http://www.linux.com/howtos/Assembly-HOWTO/mips.shtml
   7*
   8* mipsel-linux-gcc -nostdlib -mno-abicalls -fno-PIC -mabi=32 \
   9*                  -O2 -static -o hello-mips hello-mips.c
  10*
  11*/
  12#define __NR_SYSCALL_BASE       4000
  13#define __NR_exit                       (__NR_SYSCALL_BASE+  1)
  14#define __NR_write                      (__NR_SYSCALL_BASE+  4)
  15
  16static inline void exit1(int status)
  17{
  18    register unsigned long __a0 asm("$4") = (unsigned long) status;
  19
  20    __asm__ __volatile__ (
  21        "       .set push       \n"
  22        "       .set noreorder  \n"
  23        "       li      $2, %0  \n"
  24        "       syscall         \n"
  25        "       .set pop        "
  26        :
  27        : "i" (__NR_exit), "r" (__a0)
  28        : "$2", "$8", "$9", "$10", "$11", "$12", "$13", "$14", "$15", "$24",
  29          "memory");
  30}
  31
  32static inline int write(int fd, const char *buf, int len)
  33{
  34    register unsigned long __a0 asm("$4") = (unsigned long) fd;
  35    register unsigned long __a1 asm("$5") = (unsigned long) buf;
  36    register unsigned long __a2 asm("$6") = (unsigned long) len;
  37    register unsigned long __a3 asm("$7");
  38    unsigned long __v0;
  39
  40    __asm__ __volatile__ (
  41        "       .set push       \n"
  42        "       .set noreorder  \n"
  43        "       li      $2, %2  \n"
  44        "       syscall         \n"
  45        "       move    %0, $2  \n"
  46        "       .set pop        "
  47        : "=r" (__v0), "=r" (__a3)
  48        : "i" (__NR_write), "r" (__a0), "r" (__a1), "r" (__a2)
  49        : "$2", "$8", "$9", "$10", "$11", "$12", "$13", "$14", "$15", "$24",
  50          "memory");
  51
  52/*    if (__a3 == 0) */
  53        return (int) __v0;
  54/*
  55    errno = __v0;
  56    return -1;
  57 */
  58}
  59
  60void __start(void)
  61{
  62    write (1, "Hello, World!\n", 14);
  63    exit1 (42);
  64}
  65