894781 - OdinMonkey: Incorrect float abs

Status: RESOLVED FIXED

(Core :: JavaScript Engine, defect)

Description

[Jesse Ruderman]

function m(stdlib)
{
  "use asm";
  var abs = stdlib.Math.abs;
  function f(d)
  {
    d = +d;
    return (~~(5.0 - +abs(d)))|0;
  }
  return f;
}
var f = m(this);
assertEq(f(0.2), 4); // got 5, expected 4
assertEq(f(NaN), 0); // got 5, expected 0


The first bad revision is:
changeset:   http://hg.mozilla.org/mozilla-central/rev/21154eef33ac
user:        Benjamin Bouvier
date:        Mon Jul 15 14:46:03 2013 -0700
summary:     Bug 893368: in asm.js, correctly compute range for truncated Math.abs calls; r=nbp

Comment 1

[Nicolas B. Pierron [:nbp]]

The only reason why this patch might be the cause is that there is another bug which set MAbs' implicitTruncate_ flag in such case.

Comment 2

[Benjamin Bouvier [:bbouvier] (inactive)]

Attachment: fix + test case

We definitely don't want to truncate double values.

Luke, what do you think of putting all range analysis test cases in a single testRangeAnalysis file? It would avoid test files proliferation in tests/asm.js.

Comment 3

[Luke Wagner [:luke]]

Comment on attachment 777251 [details] [diff] [review]
fix + test case

Looks good and testRangeAnalysis also sounds good.

Comment 4

[Benjamin Bouvier [:bbouvier] (inactive)]

https://hg.mozilla.org/integration/mozilla-inbound/rev/79b9a4158f6c

Comment 5

[Ryan VanderMeulen [:RyanVM]]

https://hg.mozilla.org/mozilla-central/rev/79b9a4158f6c