Added option --script-snapshot in gen_snapshot to generate the snapshot of a scipt into the file.

Added option --script-snapshot in gen_snapshot to generate the snapshot of a scipt into the file.

Added option --use-script-snapshot to dart to be able to read a script from a snapshot.

Using this for dart2js produces the following result:

time dart --use-script-snapshot=dart2-js out/ReleaseIA32/dart-sdk/lib/dart2js/lib/compiler/implementation/dart2js.dart tests/language/string_test.dart -oout.js
real    0m1.733s
user    0m1.690s
sys     0m0.030s

without the snapshot the runtimes are:
time out/ReleaseIA32/dart out/ReleaseIA32/dart-sdk/lib/dart2js/lib/compiler/implementation/dart2js.dart tests/language/string_test.dart -oout.js.orig
real    0m2.406s
user    0m2.350s
sys     0m0.040s
Committed: https://code.google.com/p/dart/source/detail?r=11840

[siva, 2012-08-31 00:56:16]

synched up to TOT.

[Ivan Posva, 2012-08-31 23:20:51]

https://chromiumcodereview.appspot.com/10871092/diff/16001/runtime/bin/main.cc
File runtime/bin/main.cc (right):

https://chromiumcodereview.appspot.com/10871092/diff/16001/runtime/bin/main.c...
runtime/bin/main.cc:441: *error = strdup("Invalid script snapshot file name
specified");
You will end up here if you ever spawn another isolate from a script snapshotted
isolate.

https://chromiumcodereview.appspot.com/10871092/diff/16001/runtime/bin/main.c...
runtime/bin/main.cc:470: Dart_Invoke(builtin_lib,
Dart_NewString("_getPrintClosure"), 0, 0);
This also needs to happen when setting up the isolate for the script snapshot.

[siva, 2012-09-01 00:25:44]

Addressed comments.

https://chromiumcodereview.appspot.com/10871092/diff/16001/runtime/bin/main.cc
File runtime/bin/main.cc (right):

https://chromiumcodereview.appspot.com/10871092/diff/16001/runtime/bin/main.c...
runtime/bin/main.cc:441: *error = strdup("Invalid script snapshot file name
specified");
I have set use_script_snapshot to false after the initial load this would
prevent any further uses of the script snapshot.

SpawnUri should definitely not be using the snapshot but we need to figure out
how SpawnFunction should work. Maybe it should not call back and instead clone
the script object from the spawning isolate. I have filed a bug (4880) for this.


On 2012/08/31 23:20:51, Ivan Posva wrote:
> You will end up here if you ever spawn another isolate from a script
snapshotted
> isolate.

https://chromiumcodereview.appspot.com/10871092/diff/16001/runtime/bin/main.c...
runtime/bin/main.cc:470: Dart_Invoke(builtin_lib,
Dart_NewString("_getPrintClosure"), 0, 0);
Good point. Move this code to dartutils and call here and in gensnapshot

On 2012/08/31 23:20:51, Ivan Posva wrote:
> This also needs to happen when setting up the isolate for the script snapshot.

[Ivan Posva, 2012-09-01 00:40:39]

LGTM -ip