[MIPS] Fix syscall clone implementation

lss/linux_syscall_support.h

 /* Copyright (c) 2005-2011, Google Inc.
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 2677 matching lines @@
                           type5 arg5,type6 arg6) {                            \
         LSS_REG(4, arg1); LSS_REG(5, arg2); LSS_REG(6, arg3);                 \
         LSS_REG(7, arg4); LSS_REG(8, arg5); LSS_REG(9, arg6);                 \
         LSS_BODY(type, name, "+r", "r"(__r4), "r"(__r5), "r"(__r6),           \
                  "r"(__r8), "r"(__r9));                                       \
       }
     #endif
     LSS_INLINE int LSS_NAME(clone)(int (*fn)(void *), void *child_stack,
                                    int flags, void *arg, int *parent_tidptr,
                                    void *newtls, int *child_tidptr) {
-      register unsigned long __v0 __asm__("$2");
+      register unsigned long __v0 __asm__("$2") = -EINVAL;
       register unsigned long __r7 __asm__("$7") = (unsigned long)newtls;
       {
         register int   __flags __asm__("$4") = flags;
         register void *__stack __asm__("$5") = child_stack;
         register void *__ptid  __asm__("$6") = parent_tidptr;
         register int  *__ctid  __asm__("$8") = child_tidptr;
         __asm__ __volatile__(
           #if _MIPS_SIM == _MIPS_SIM_ABI32 && _MIPS_SZPTR == 32
                              "subu  $29,24\n"
           #elif _MIPS_SIM == _MIPS_SIM_NABI32
                              "sub   $29,16\n"
           #else
                              "dsubu $29,16\n"
           #endif
 
                              /* if (fn == NULL || child_stack == NULL)
                               *   return -EINVAL;
                               */
-                             "li    %0,%2\n"
+                             "beqz  %4,1f\n"
                              "beqz  %5,1f\n"
-                             "beqz  %6,1f\n"
 
                              /* Push "arg" and "fn" onto the stack that will be
                               * used by the child.
                               */
           #if _MIPS_SIM == _MIPS_SIM_ABI32 && _MIPS_SZPTR == 32
-                             "subu  %6,32\n"
-                             "sw    %5,0(%6)\n"
-                             "sw    %8,4(%6)\n"
+                             "subu  %5,32\n"
+                             "sw    %4,0(%5)\n"
+                             "sw    %7,4(%5)\n"
           #elif _MIPS_SIM == _MIPS_SIM_NABI32
-                             "sub   %6,32\n"
-                             "sw    %5,0(%6)\n"
-                             "sw    %8,8(%6)\n"
+                             "sub   %5,32\n"
+                             "sw    %4,0(%5)\n"
+                             "sw    %7,8(%5)\n"
           #else
-                             "dsubu %6,32\n"
-                             "sd    %5,0(%6)\n"
-                             "sd    %8,8(%6)\n"
+                             "dsubu %5,32\n"
+                             "sd    %4,0(%5)\n"
+                             "sd    %7,8(%5)\n"
           #endif
 
                              /* $7 = syscall($4 = flags,
                               *              $5 = child_stack,
                               *              $6 = parent_tidptr,
                               *              $7 = newtls,
                               *              $8 = child_tidptr)
                               */
-                             "li    $2,%3\n"
+                             "li    $2,%2\n"
                              "syscall\n"
 
                              /* if ($7 != 0)
                               *   return $2;
                               */
                              "bnez  $7,1f\n"
                              "bnez  $2,1f\n"
 
                              /* In the child, now. Call "fn(arg)".
                               */
           #if _MIPS_SIM == _MIPS_SIM_ABI32 && _MIPS_SZPTR == 32
                             "lw    $25,0($29)\n"
                             "lw    $4,4($29)\n"
           #elif _MIPS_SIM == _MIPS_SIM_NABI32
                             "lw    $25,0($29)\n"
                             "lw    $4,8($29)\n"
           #else
                             "ld    $25,0($29)\n"
                             "ld    $4,8($29)\n"
           #endif
                             "jalr  $25\n"
 
                              /* Call _exit($2)
                               */
                             "move  $4,$2\n"
-                            "li    $2,%4\n"
+                            "li    $2,%3\n"
                             "syscall\n"
 
                            "1:\n"
           #if _MIPS_SIM == _MIPS_SIM_ABI32 && _MIPS_SZPTR == 32
                              "addu  $29, 24\n"
           #elif _MIPS_SIM == _MIPS_SIM_NABI32
                              "add   $29, 16\n"
           #else
                              "daddu $29,16\n"
           #endif
                              : "+r" (__v0), "+r" (__r7)
-                             : "i"(-EINVAL), "i"(__NR_clone), "i"(__NR_exit),
-                               "r"(fn), "r"(__stack), "r"(__flags), "r"(arg),
-                               "r"(__ptid), "r"(__r7), "r"(__ctid)
+                             : "i"(__NR_clone), "i"(__NR_exit), "r"(fn),
+                               "r"(__stack), "r"(__flags), "r"(arg),
+                               "r"(__ptid), "r"(__ctid)
                              : "$9", "$10", "$11", "$12", "$13", "$14", "$15",
                                "$24", "$25", "memory");
       }
       LSS_RETURN(int, __v0, __r7);
     }
   #elif defined (__PPC__)
     #undef  LSS_LOADARGS_0
     #define LSS_LOADARGS_0(name, dummy...)                                    \
         __sc_0 = __NR_##name
     #undef  LSS_LOADARGS_1
@@ skipping 1225 matching lines @@
 # pragma pop_macro("fstat64")
 # pragma pop_macro("lstat64")
 #endif
 
 #if defined(__cplusplus) && !defined(SYS_CPLUSPLUS)
 }
 #endif
 
 #endif
 #endif