[PATCH] D69978: Separately track input and output denormal mode

[Andy Kaylor via Phabricator via llvm-commits]

andrew.w.kaylor added inline comments.


================
Comment at: llvm/docs/LangRef.rst:1822
 
 ``"denorm-fp-mode"``
+   This indicates the subnormal handling that may be assumed for the
----------------
I don't like the definition of this attribute. It's not reader-friendly. The comma-separated pair format has no indication which value refers to inputs and which refers to outputs. Also, while this predates your changes, I think the meanings of the current choices are unclear. 

What would you think of a comma-separated list with the following possibilities?


```
allow-denormals (default)
inputs-are-zero (outputs not flushed)
inputs-are-zero, outputs-are-zero
inputs-are-zero, outputs-are-positive-zero
inputs-are-positivezero (outputs not flushed)
inputs-are-positivezero, outputs-are-zero
inputs-are-positivezero, outputs-are-positive-zero
denormal-outputs-are-zero (inputs are unchanged)
denormal-outputs-are-positive-zero (inputs are unchanged)

```
I'd also be open to abbreviations. I don't know if "daz" and "ftz" are readable to everyone, but I'm more comfortable with them. That would make the options something like this.


```
allow-denormals
daz
daz, ftz
daz, ftz+
daz+
daz+, ftz
daz+, ftz+
ftz
ftz+
```


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D69978/new/

https://reviews.llvm.org/D69978