915934 - IonMonkey: clean-ups for UInt32ToDouble

Status: RESOLVED FIXED

(Core :: JavaScript Engine, defect)

Description

[Benjamin Bouvier [:bbouvier] (inactive)]

Per comment 22 in bug 913282,

(In reply to Hannes Verschore [:h4writer] from comment #22)
> 
> (Value &) v could be typed as a double, but still fit into a float. So I
> think we want to fold that too?
> 
> >      _(UInt32ToDouble)               \
> > +    _(UInt32ToFloat32)              \
> 
> Since this is only used in odinmonkey, this should be AsmJSUInt32ToFloat32
> 
> Also I think it's better to create convertUInt32ToFloat32(input, output,
> temp) for the x86 variant. And move input to temp, when the registers aren't
> the same. That way it doesn't clobber input register anymore, unnoticeable.
> 

- fold also constant double Value
- rename UInt32ToDouble into AsmJSUInt32ToDouble
- make the mov of visitUInt32ToDouble happen in convertUInt32ToDouble

Comment 1

[Benjamin Bouvier [:bbouvier] (inactive)]

Attachment: cleanups

Changing the convertUInt32ToDouble so that it takes more arguments was slightly more complicated, as there are some calls in IonMacroAssembler with a non trivial path, so I preferred not changing the function.

Also, AsmJS stores uint32 in int32, so there actually can't be a Double value during constant folding.

Comment 2

[Hannes Verschore [:h4writer]]

Comment on attachment 804151 [details] [diff] [review]
cleanups

Review of attachment 804151 [details] [diff] [review]:
-----------------------------------------------------------------

Thanks!

Comment 3

[Benjamin Bouvier [:bbouvier] (inactive)]

https://hg.mozilla.org/integration/mozilla-inbound/rev/ae623dc4f044

Comment 4

[Ed Morley [:emorley]]

https://hg.mozilla.org/mozilla-central/rev/ae623dc4f044