Disallow garbage collection at another site in the LoadCallback ICs....

Disallow garbage collection at another site in the LoadCallback ICs.
MacroAssembler::PopHandleScope emits a runtime call (through a stub),
which should not be allowed to perform a GC but return a failure
instead.

BUG=30790
TEST=none


Committed: http://code.google.com/p/v8/source/detail?r=3501

[iposva, 2009-12-20 05:04:50]

Kevin,

I think you are fighting a loosing battle here. While this change will certainly
fix the reported problem, I think a safer approach would be to not drop the
handles when calling ComputeLoadCallback in the first place.

LGTM especially if you clarify the confusing comment.

-Ivan

http://codereview.chromium.org/504071/diff/1/4
File src/ia32/stub-cache-ia32.cc (right):

http://codereview.chromium.org/504071/diff/1/4#newcode818
src/ia32/stub-cache-ia32.cc:818: // collection but instead return a failure
object.
This comment is very confusing. Isn't it so that emitting the code to call
PopHandleScope can cause a GC? This is not what I read in your comment here.
At the least please clarify that the two instances of the word "call" do not
mean the same call.