Simplify the check when to perform loop invariant code motion.

Simplify the check when to perform loop invariant code motion.

Allow HChange instructions to be hoisted out of loops. To avoid
unnecessary code motion we don't hoist instructions from blocks that
have been marked containing an unconditional deoptimization.
Committed: http://code.google.com/p/v8/source/detail?r=8245

[Kevin Millikin (Chromium), 2011-06-09 15:18:00]

As discussed offline, we might need to propagate this flag to dominated blocks.

http://codereview.chromium.org/7003087/diff/1/src/hydrogen.cc
File src/hydrogen.cc (right):

http://codereview.chromium.org/7003087/diff/1/src/hydrogen.cc#newcode1452
src/hydrogen.cc:1452: if (!AllowCodeMotion()) return false;
return AllowCodeMotion() && !instr->block()->IsDeoptimizing();

[fschneider, 2011-06-09 15:46:47]

Addressed comments.

http://codereview.chromium.org/7003087/diff/1/src/hydrogen.cc
File src/hydrogen.cc (right):

http://codereview.chromium.org/7003087/diff/1/src/hydrogen.cc#newcode1452
src/hydrogen.cc:1452: if (!AllowCodeMotion()) return false;
On 2011/06/09 15:18:00, Kevin Millikin wrote:
> return AllowCodeMotion() && !instr->block()->IsDeoptimizing();

Done.

[Kevin Millikin (Chromium), 2011-06-09 15:48:44]

LGTM.