softfloat: Remove fallback rule from pickNaN()

Now that all targets have been converted to explicitly set a NaN
propagation rule, we can remove the set of target ifdefs (which now
list every target) and clean up the references to fallback behaviour
for float_2nan_prop_none.

The "default" case in the switch will catch any remaining places
where status->float_2nan_prop_rule was not set by the target.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20241025141254.2141506-22-peter.maydell@linaro.org

1 files changed, 3 insertions, 7 deletions

diff --git a/include/fpu/softfloat-types.h b/include/fpu/softfloat-types.h
index 5cd5a0d0ae..8f39691dfd 100644
--- a/include/fpu/softfloat-types.h
+++ b/include/fpu/softfloat-types.h
@@ -178,13 +178,9 @@ typedef enum __attribute__((__packed__)) {
  * If default_nan_mode is enabled then it is valid not to set a
  * NaN propagation rule, because the softfloat code guarantees
  * not to try to pick a NaN to propagate in default NaN mode.
- *
- * For transition, currently the 'none' rule will cause us to
- * fall back to picking the propagation rule based on the existing
- * ifdef ladder. When all targets are converted it will be an error
- * not to set the rule in float_status unless in default_nan_mode,
- * and we will assert if we need to handle an input NaN and no
- * rule was selected.
+ * When not in default-NaN mode, it is an error for the target
+ * not to set the rule in float_status, and we will assert if
+ * we need to handle an input NaN and no rule was selected.
  */
 typedef enum __attribute__((__packed__)) {
     /* No propagation rule specified */