Eagerly deoptimize on never-executed code-paths.

Eagerly deoptimize on never-executed code-paths.

If type-feedback indicates that an expression was never executed in
the non-optimized code, we insert a forced deoptimization right away
to enable re-optimization if we ever hit this path.

With this change we still continue to build the graph. As a next step, we
should remove the dead code after the deoptimize.

I had to remove one assert about the optimization status in a test since
we now immediately deoptimize after exiting the loop that triggers OSR.

Also remove a restriction that control-flow from an inlined function in a
test context always reaches both true- and false-target.
Committed: http://code.google.com/p/v8/source/detail?r=8140

[danno, 2011-06-01 10:11:27]

LGTM with my suggested renaming :-)

http://codereview.chromium.org/7105015/diff/1/src/hydrogen-instructions.h
File src/hydrogen-instructions.h (right):

http://codereview.chromium.org/7105015/diff/1/src/hydrogen-instructions.h#new...
src/hydrogen-instructions.h:99: V(EagerDeoptimize)                           \
My gut feeling is that  Eager vs. Lazy isn't the right distinction. I think I
would prefer this to be a "SoftDeoptimize" and the other one to be explicitly a
"HardDeoptimize".

[fschneider, 2011-06-01 11:04:48]

http://codereview.chromium.org/7105015/diff/1/src/hydrogen-instructions.h
File src/hydrogen-instructions.h (right):

http://codereview.chromium.org/7105015/diff/1/src/hydrogen-instructions.h#new...
src/hydrogen-instructions.h:99: V(EagerDeoptimize)                           \
On 2011/06/01 10:11:27, danno wrote:
> My gut feeling is that  Eager vs. Lazy isn't the right distinction. I think I
> would prefer this to be a "SoftDeoptimize" and the other one to be explicitly
a
> "HardDeoptimize". 

Done.