math-emu: Add support for reporting exact invalid exception

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>

1 files changed, 8 insertions, 4 deletions

diff --git a/include/math-emu/op-common.h b/include/math-emu/op-common.h
index bb46e7645d53..cc1ec396f8d6 100644
--- a/include/math-emu/op-common.h
+++ b/include/math-emu/op-common.h
@@ -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:                                              \