Infer the range of XOR as limited by the highest possible changed bit.

Infer the range of XOR as limited by the highest possible changed bit.

R=ulan@chromium.org

Committed: https://code.google.com/p/v8/source/detail?r=14933

[Toon Verwaest, 2013-06-04 12:05:27]

PTAL

[Sven Panne, 2013-06-04 12:15:27]

Extremely important DBC... :-D

https://chromiumcodereview.appspot.com/16361003/diff/1/src/hydrogen-instructi...
File src/hydrogen-instructions.cc (right):

https://chromiumcodereview.appspot.com/16361003/diff/1/src/hydrogen-instructi...
src/hydrogen-instructions.cc:2314: if (left()->range() != NULL &&
right()->range() != NULL) {
We traditionally use HasRange() for stuff like this.

[ulan, 2013-06-04 12:26:28]

lgtm

[Toon Verwaest, 2013-06-04 12:26:44]

Committed patchset #4 manually as r14933 (presubmit successful).

[Florian Schneider, 2013-06-07 09:20:17]

On 2013/06/04 12:26:44, Toon Verwaest wrote:
> Committed patchset #4 manually as r14933 (presubmit successful).

https://codereview.chromium.org/9156001/ unfortunately never landed, but it is
more precise and more general as it covers all binary bitwise ops. I think it
should replace this CL.

[Toon Verwaest, 2013-06-07 09:41:55]

Thanks for the ref to that CL. I'll have a look at addressing Svens comments on
that CL on Monday; and replace my ad-hoc approach.