linux-user: make MIPS and ARM eabi use same argument reordering

MIPS uses similar calling convention than ARM eabi, where when using
64-bit values some registers are skipped. This patch makes MIPS and ARM
eabi share the argument reordering code.

This affects ftruncate64, creating insane sized fails (or just failing).

Cc: Wesley W. Terpstra <terpstra@debian.org>
Signed-off-by: NRiku Voipio <riku.voipio@linaro.org>

linux-user/syscall.c

@@ -580,6 +580,17 @@ extern int setfsuid(int);
 extern int setfsgid(int);
 extern int setgroups(int, gid_t *);
 
+/* ARM EABI and MIPS expect 64bit types aligned even on pairs or registers */
+#ifdef TARGET_ARM 
+static inline int regpairs_aligned(void *cpu_env) {
+    return ((((CPUARMState *)cpu_env)->eabi) == 1) ;
+}
+#elif defined(TARGET_MIPS)
+static inline int regpairs_aligned(void *cpu_env) { return 1; }
+#else
+static inline int regpairs_aligned(void *cpu_env) { return 0; }
+#endif
+
 #define ERRNO_TABLE_SIZE 1200
 
 /* target_to_host_errno_table[] is initialized from
@@ -4375,13 +4386,10 @@ static inline abi_long target_truncate64(void *cpu_env, const char *arg1,
                                          abi_long arg3,
                                          abi_long arg4)
 {
-#ifdef TARGET_ARM
-    if (((CPUARMState *)cpu_env)->eabi)
-      {
+    if (regpairs_aligned(cpu_env)) {
         arg2 = arg3;
         arg3 = arg4;
-      }
-#endif
+    }
     return get_errno(truncate64(arg1, target_offset64(arg2, arg3)));
 }
 #endif
@@ -4392,13 +4400,10 @@ static inline abi_long target_ftruncate64(void *cpu_env, abi_long arg1,
                                           abi_long arg3,
                                           abi_long arg4)
 {
-#ifdef TARGET_ARM
-    if (((CPUARMState *)cpu_env)->eabi)
-      {
+    if (regpairs_aligned(cpu_env)) {
         arg2 = arg3;
         arg3 = arg4;
-      }
-#endif
+    }
     return get_errno(ftruncate64(arg1, target_offset64(arg2, arg3)));
 }
 #endif
@@ -6857,20 +6862,16 @@ abi_long do_syscall(void *cpu_env, int num, abi_long arg1,
 #endif
 #ifdef TARGET_NR_pread
     case TARGET_NR_pread:
-#ifdef TARGET_ARM
-        if (((CPUARMState *)cpu_env)->eabi)
+        if (regpairs_aligned(cpu_env))
             arg4 = arg5;
-#endif
         if (!(p = lock_user(VERIFY_WRITE, arg2, arg3, 0)))
             goto efault;
         ret = get_errno(pread(arg1, p, arg3, arg4));
         unlock_user(p, arg2, ret);
         break;
     case TARGET_NR_pwrite:
-#ifdef TARGET_ARM
-        if (((CPUARMState *)cpu_env)->eabi)
+        if (regpairs_aligned(cpu_env))
             arg4 = arg5;
-#endif
         if (!(p = lock_user(VERIFY_READ, arg2, arg3, 1)))
             goto efault;
         ret = get_errno(pwrite(arg1, p, arg3, arg4));
@@ -7621,14 +7622,11 @@ abi_long do_syscall(void *cpu_env, int num, abi_long arg1,
 #ifdef TARGET_NR_readahead
     case TARGET_NR_readahead:
 #if TARGET_ABI_BITS == 32
-#ifdef TARGET_ARM
-        if (((CPUARMState *)cpu_env)->eabi)
-        {
+        if (regpairs_aligned(cpu_env)) {
             arg2 = arg3;
             arg3 = arg4;
             arg4 = arg5;
         }
-#endif
         ret = get_errno(readahead(arg1, ((off64_t)arg3 << 32) | arg2, arg4));
 #else
         ret = get_errno(readahead(arg1, arg2, arg3));