target-alpha: Raise EXC_M_INV properly for fp inputs

Ignore DNZ if software completion isn't used.  Raise INV for
denormals in system mode so the OS completion handler sees them.

Reported-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Richard Henderson <rth@twiddle.net>

1 files changed, 7 insertions, 0 deletions

diff --git a/target-alpha/translate.c b/target-alpha/translate.c
index f0556b0ef3..4c441a91a3 100644
--- a/target-alpha/translate.c
+++ b/target-alpha/translate.c
@@ -658,6 +658,13 @@ static TCGv gen_ieee_input(DisasContext *ctx, int reg, int fn11, int is_cmp)
             } else {
                 gen_helper_ieee_input(cpu_env, val);
             }
+        } else {
+#ifndef CONFIG_USER_ONLY
+            /* In system mode, raise exceptions for denormals like real
+               hardware.  In user mode, proceed as if the OS completion
+               handler is handling the denormal as per spec.  */
+            gen_helper_ieee_input_s(cpu_env, val);
+#endif
         }
     }
     return val;