math-emu: Add support for reporting exact invalid exception
Kumar Gala [Fri, 27 Jun 2008 14:39:00 +0000 (09:39 -0500)]
Some architectures (like powerpc) provide status information on the exact
type of invalid exception.  This is pretty straight forward as we already
report invalid exceptions via FP_SET_EXCEPTION.

We add new flags (FP_EX_INVALID_*) the architecture code can define if it
wants the exact invalid exception reported.

We had to split out the INF/INF and 0/0 cases for divide to allow reporting
the two invalid forms properly.

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Acked-by: David S. Miller <davem@davemloft.net>

include/math-emu/op-common.h
include/math-emu/soft-fp.h

index bb46e76..cc1ec39 100644 (file)
@@ -73,7 +73,7 @@ do {                                                                  \
        X##_c = FP_CLS_NAN;                                             \
        /* Check for signaling NaN */                                   \
        if (!(_FP_FRAC_HIGH_RAW_##fs(X) & _FP_QNANBIT_##fs))            \
-         FP_SET_EXCEPTION(FP_EX_INVALID);                              \
+         FP_SET_EXCEPTION(FP_EX_INVALID | FP_EX_INVALID_SNAN);         \
       }                                                                        \
     break;                                                             \
   }                                                                    \
@@ -324,7 +324,7 @@ do {                                                                             \
        _FP_FRAC_SET_##wc(R, _FP_NANFRAC_##fs);                              \
        R##_s = _FP_NANSIGN_##fs;                                            \
        R##_c = FP_CLS_NAN;                                                  \
-       FP_SET_EXCEPTION(FP_EX_INVALID);                                     \
+       FP_SET_EXCEPTION(FP_EX_INVALID | FP_EX_INVALID_ISI);                 \
        break;                                                               \
       }                                                                             \
     /* FALLTHRU */                                                          \
@@ -431,7 +431,7 @@ do {                                                        \
     R##_s = _FP_NANSIGN_##fs;                          \
     R##_c = FP_CLS_NAN;                                        \
     _FP_FRAC_SET_##wc(R, _FP_NANFRAC_##fs);            \
-    FP_SET_EXCEPTION(FP_EX_INVALID);                   \
+    FP_SET_EXCEPTION(FP_EX_INVALID | FP_EX_INVALID_IMZ);\
     break;                                             \
                                                        \
   default:                                             \
@@ -490,11 +490,15 @@ do {                                                      \
     break;                                             \
                                                        \
   case _FP_CLS_COMBINE(FP_CLS_INF,FP_CLS_INF):         \
+    R##_s = _FP_NANSIGN_##fs;                          \
+    R##_c = FP_CLS_NAN;                                        \
+    _FP_FRAC_SET_##wc(R, _FP_NANFRAC_##fs);            \
+    FP_SET_EXCEPTION(FP_EX_INVALID | FP_EX_INVALID_IDI);\
   case _FP_CLS_COMBINE(FP_CLS_ZERO,FP_CLS_ZERO):       \
     R##_s = _FP_NANSIGN_##fs;                          \
     R##_c = FP_CLS_NAN;                                        \
     _FP_FRAC_SET_##wc(R, _FP_NANFRAC_##fs);            \
-    FP_SET_EXCEPTION(FP_EX_INVALID);                   \
+    FP_SET_EXCEPTION(FP_EX_INVALID | FP_EX_INVALID_ZDZ);\
     break;                                             \
                                                        \
   default:                                             \
index a6f873b..3f284bc 100644 (file)
 #ifndef FP_EX_INVALID
 #define FP_EX_INVALID          0
 #endif
+#ifndef FP_EX_INVALID_SNAN
+#define FP_EX_INVALID_SNAN     0
+#endif
+/* inf - inf */
+#ifndef FP_EX_INVALID_ISI
+#define FP_EX_INVALID_ISI      0
+#endif
+/* inf / inf */
+#ifndef FP_EX_INVALID_IDI
+#define FP_EX_INVALID_IDI      0
+#endif
+/* 0 / 0 */
+#ifndef FP_EX_INVALID_ZDZ
+#define FP_EX_INVALID_ZDZ      0
+#endif
+/* inf * 0 */
+#ifndef FP_EX_INVALID_IMZ
+#define FP_EX_INVALID_IMZ      0
+#endif
 #ifndef FP_EX_OVERFLOW
 #define FP_EX_OVERFLOW         0
 #endif