931488 - basic range analysis for MBoundsCheck, MArrayLength, MRandom, MMathFunction

Status: RESOLVED FIXED

(Core :: JavaScript Engine: JIT, enhancement)

Description

[Dan Gohman [:sunfish]]

Attachment: range-more-compute-ranges.patch

Attached is a patch which implements basic range analysis for several more MIR nodes.

Comment 1

[Nicolas B. Pierron [:nbp]]

Comment on attachment 822916 [details] [diff] [review]
range-more-compute-ranges.patch

Review of attachment 822916 [details] [diff] [review]:
-----------------------------------------------------------------

Awesome, thanks for adding these functions.  I am sure this would be useful in tons of cases :)

::: js/src/jit/RangeAnalysis.cpp
@@ +1410,5 @@
> +
> +void
> +MRandom::computeRange()
> +{
> +    setRange(Range::NewDoubleRange(0.0, 1.0));

hum … Does not sounds that Random to me :P

Comment 2

[Dan Gohman [:sunfish]]

(In reply to Nicolas B. Pierron [:nbp] from comment #1)
> Comment on attachment 822916 [details] [diff] [review]
> range-more-compute-ranges.patch
> 
> Review of attachment 822916 [details] [diff] [review]:
> -----------------------------------------------------------------
> 
> Awesome, thanks for adding these functions.  I am sure this would be useful
> in tons of cases :)
> 
> ::: js/src/jit/RangeAnalysis.cpp
> @@ +1410,5 @@
> > +
> > +void
> > +MRandom::computeRange()
> > +{
> > +    setRange(Range::NewDoubleRange(0.0, 1.0));
> 
> hum … Does not sounds that Random to me :P

It's a double range between 0 and 1.

https://hg.mozilla.org/integration/mozilla-inbound/rev/dd86744caa3a

Comment 3

[Wes Kocher (:KWierso) (Not reading bugmail; email directly if needed)]

https://hg.mozilla.org/mozilla-central/rev/dd86744caa3a