floating point environment/exceptions support for mips

arch/mips/bits/fenv.h

@@ -1,10 +1,20 @@
-#define FE_ALL_EXCEPT 0
-#define FE_TONEAREST  0
+#define FE_INEXACT    4
+#define FE_UNDERFLOW  8
+#define FE_OVERFLOW   16
+#define FE_DIVBYZERO  32
+#define FE_INVALID    64
 
-typedef unsigned long fexcept_t;
+#define FE_ALL_EXCEPT 124
+
+#define FE_TONEAREST  0
+#define FE_TOWARDZERO 1
+#define FE_UPWARD     2
+#define FE_DOWNWARD   3
+
+typedef unsigned short fexcept_t;
 
 typedef struct {
-	unsigned long __cw;
+	unsigned __cw;
 } fenv_t;
 
 #define FE_DFL_ENV      ((const fenv_t *) -1)