Improve code coverage generation.

Improve code coverage generation.

- Remove function name from output.
- Remove column from output (side effect: We can use fast version of
  GetTokenLocation())
- Insert HANDLESCOPES
- Fold source file entries where easily possible, i.e., fold consecutive entries
  created by functions in the same source file.
- Change format to

  [{
     "source": "...",
     "hits": [<line>,<hitcount>, ...]
   }, ... ]

BUG=
R=iposva@google.com

Committed: https://code.google.com/p/dart/source/detail?r=28030

[Michael Lippautz (Google), 2013-09-25 23:06:05]

Missing: Aggregate IC counts in a function and add the count to
function.token_pos() line (?)

Issue comes up when you merge multiple coverage files and have one file with 0
hits for a function, and another file with some hits.

[Michael Lippautz (Google), 2013-09-26 17:15:39]

PTAL

[Michael Lippautz (Google), 2013-09-27 17:42:26]

PTAL

Example:
mkdir /tmp/dart2jscov
./tools/build.py -m release -a ia32
DART_VM_OPTIONS="--coverage-dir=/tmp/dart2jscov" ./tools/test.py -m release -a
ia32 -r d8 -c dart2js language
out/ReleaseIA32/dart --package-root=out/ReleaseIA32/packages
tools/full-coverage.dart --sdk-root=out/ReleaseIA32/dart-sdk/
--package-root=out/ReleaseIA32/packages/ -i /tmp/dart2jscov -o /tmp/dart2js.txt
-j 12 -r -v

[Ivan Posva, 2013-09-27 20:19:54]

C++ code LGTM. We can add some of the stuff later if needed.

-Ivan

https://codereview.chromium.org/24654003/diff/16001/runtime/vm/coverage.cc
File runtime/vm/coverage.cc (right):

https://codereview.chromium.org/24654003/diff/16001/runtime/vm/coverage.cc#ne...
runtime/vm/coverage.cc:48: if (function.HasCode()) {
As we discussed to get more complete coverage of functions it might be necessary
to compile all of the functions instead of just assigning them a zero hit count.

https://codereview.chromium.org/24654003/diff/16001/runtime/vm/coverage.cc#ne...
runtime/vm/coverage.cc:83: OS::SNPrint(line_str, kMaxLineRangeLen, "%d-%d",
start_line, end_line);
Please remove the : from the description of the change as well.

https://codereview.chromium.org/24654003/diff/16001/runtime/vm/coverage.cc#ne...
runtime/vm/coverage.cc:102: while (i < functions.Length()) {
As discussed off-line we also need to iterate over the closure functions to
gather their coverage once we have finished traversing all functions.

https://codereview.chromium.org/24654003/diff/16001/runtime/vm/coverage.cc#ne...
runtime/vm/coverage.cc:141: if (cls.is_finalized()) {
To have a more complete picture we should call EnsureIsFinalized instead of
skipping classes here.

https://codereview.chromium.org/24654003/diff/16001/runtime/vm/coverage.h
File runtime/vm/coverage.h (right):

https://codereview.chromium.org/24654003/diff/16001/runtime/vm/coverage.h#new...
runtime/vm/coverage.h:10: #include "vm/object.h"
Why don't you forward declare class Array below?

https://codereview.chromium.org/24654003/diff/16001/tools/full-coverage.dart
File tools/full-coverage.dart (right):

https://codereview.chromium.org/24654003/diff/16001/tools/full-coverage.dart#...
tools/full-coverage.dart:302: int filesPerWorker = (files.length /
env.workers).toInt();
What do you do with the remainder? Also we have this excellent thing called a
mustache divide: ~/

[Michael Lippautz (Google), 2013-09-27 21:46:50]

Addressed comments and included closure handling.

The merging script can still deal with ranges, although we don't emit them
anymore. (Maybe in future?)

https://codereview.chromium.org/24654003/diff/16001/runtime/vm/coverage.cc
File runtime/vm/coverage.cc (right):

https://codereview.chromium.org/24654003/diff/16001/runtime/vm/coverage.cc#ne...
runtime/vm/coverage.cc:48: if (function.HasCode()) {
On 2013/09/27 20:19:54, Ivan Posva wrote:
> As we discussed to get more complete coverage of functions it might be
necessary
> to compile all of the functions instead of just assigning them a zero hit
count.

Done.

https://codereview.chromium.org/24654003/diff/16001/runtime/vm/coverage.cc#ne...
runtime/vm/coverage.cc:83: OS::SNPrint(line_str, kMaxLineRangeLen, "%d-%d",
start_line, end_line);
On 2013/09/27 20:19:54, Ivan Posva wrote:
> Please remove the : from the description of the change as well.

Done. There are no ranges anymore.

https://codereview.chromium.org/24654003/diff/16001/runtime/vm/coverage.cc#ne...
runtime/vm/coverage.cc:102: while (i < functions.Length()) {
On 2013/09/27 20:19:54, Ivan Posva wrote:
> As discussed off-line we also need to iterate over the closure functions to
> gather their coverage once we have finished traversing all functions.

Done.

https://codereview.chromium.org/24654003/diff/16001/runtime/vm/coverage.cc#ne...
runtime/vm/coverage.cc:141: if (cls.is_finalized()) {
On 2013/09/27 20:19:54, Ivan Posva wrote:
> To have a more complete picture we should call EnsureIsFinalized instead of
> skipping classes here.

Done.

https://codereview.chromium.org/24654003/diff/16001/runtime/vm/coverage.h
File runtime/vm/coverage.h (right):

https://codereview.chromium.org/24654003/diff/16001/runtime/vm/coverage.h#new...
runtime/vm/coverage.h:10: #include "vm/object.h"
On 2013/09/27 20:19:54, Ivan Posva wrote:
> Why don't you forward declare class Array below?

Done.

https://codereview.chromium.org/24654003/diff/16001/tools/full-coverage.dart
File tools/full-coverage.dart (right):

https://codereview.chromium.org/24654003/diff/16001/tools/full-coverage.dart#...
tools/full-coverage.dart:302: int filesPerWorker = (files.length /
env.workers).toInt();
On 2013/09/27 20:19:54, Ivan Posva wrote:
> What do you do with the remainder? Also we have this excellent thing called a
> mustache divide: ~/

Done.

[Michael Lippautz (Google), 2013-09-27 23:22:55]

Committed patchset #4 manually as r28030 (presubmit successful).