Limit length of strings copied into a heap snapshot

A page created a number of ConsStrings that refer to one big string.
Each such string requires small amount of heap memory.
Heap snapshot generator copies all the strings into internal hash map for future use.
The each copy requires much more memory than original v8 string.

I made a workaround for this. The snapshot will copy only first 1024 symbols.    
A simple drive-by fix was made for a performance problem in ToCString implementation.

BUG=v8:1816
TEST=none

Committed: http://code.google.com/p/v8/source/detail?r=9928

[mnaganov (inactive), 2011-11-09 11:45:10]

On 2011/11/09 10:11:11, loislo wrote:

Overall is good, please fix comments.

In the description, please provide a title, e.g. "Limit length of strings copied
into a heap snapshot" and change "BUG=" to "BUG=v8:" to make a proper reference.

[mnaganov (inactive), 2011-11-09 11:45:23]

http://codereview.chromium.org/8509003/diff/1/src/objects.cc
File src/objects.cc (right):

http://codereview.chromium.org/8509003/diff/1/src/objects.cc#newcode5832
src/objects.cc:5832: character_position++;
This can be moved up into the loop clause.

http://codereview.chromium.org/8509003/diff/1/src/objects.cc#newcode5853
src/objects.cc:5853: character_position++;
Same here.

http://codereview.chromium.org/8509003/diff/1/src/profile-generator.cc
File src/profile-generator.cc (right):

http://codereview.chromium.org/8509003/diff/1/src/profile-generator.cc#newcod...
src/profile-generator.cc:156: length = kMaxNameSize > length ? length :
kMaxNameSize;
length = Min(length, kMaxNameSize)

http://codereview.chromium.org/8509003/diff/1/src/profile-generator.h
File src/profile-generator.h (right):

http://codereview.chromium.org/8509003/diff/1/src/profile-generator.h#newcode77
src/profile-generator.h:77: static const uint32_t kMaxNameSize;
Static consts are preferred to be initialized in the class declaration.

[loislo, 2011-11-09 11:56:06]

comments addressed

[mnaganov (inactive), 2011-11-09 12:07:33]

On 2011/11/09 11:56:06, loislo wrote:
> comments addressed

LGTM, I'll land.