Reimplement (address -> code) mapping from tickprocessor.py in JS.

Reimplement (address -> code) mapping from tickprocessor.py in JS.

Found a pair of bugs concerned with border cases in the original implementation.

Committed: http://code.google.com/p/v8/source/detail?r=1726

[Søren Thygesen Gjesse, 2009-04-16 06:08:24]

LGTM!

http://codereview.chromium.org/67191/diff/1/4
File tools/codemap.js (right):

http://codereview.chromium.org/67191/diff/1/4#newcode46
Line 46: * Deleted code entries.
Please add "Used for JIT compiled code which has been garbage collected" to the
comment.

http://codereview.chromium.org/67191/diff/1/4#newcode199
Line 199: this.name = opt_name || '';
How about adding the empty name to the prototype:

devtools.profiler.CodeMap.CodeEntry.prototype.name = '';

And than changing this assignament to:

if (opt_name) {
  this.name = opt_name
}

[Mikhail Naganov, 2009-04-16 16:05:38]

http://codereview.chromium.org/67191/diff/1/4
File tools/codemap.js (right):

http://codereview.chromium.org/67191/diff/1/4#newcode46
Line 46: * Deleted code entries.
On 2009/04/16 06:08:24, Søren Gjesse wrote:
> Please add "Used for JIT compiled code which has been garbage collected" to
the
> comment.

Done.

http://codereview.chromium.org/67191/diff/1/4#newcode199
Line 199: this.name = opt_name || '';
On 2009/04/16 06:08:24, Søren Gjesse wrote:
> How about adding the empty name to the prototype:
> 
> devtools.profiler.CodeMap.CodeEntry.prototype.name = '';
> 
> And than changing this assignament to:
> 
> if (opt_name) {
>   this.name = opt_name
> }
> 
> 

I'll better not. First, this is the commonly used idiom for accessing optional
parameters in JS. Second, it's 4 vs. 1 lines of code.