dart2js cps: Speed up integrity checking some more.

dart2js cps: Speed up integrity checking some more.

Share the Map instance between different passes, so we don't need to
allocate and resize the hash table from scratch every time.

BUG=
R=sra@google.com

Committed: https://github.com/dart-lang/sdk/commit/1e23ef0cbb1d50f3225a29eadaaf31ffd51b3cdc

[asgerf, 2015-10-15 10:13:29]

asgerf@google.com changed reviewers:
+ sra@google.com

[asgerf, 2015-10-15 10:13:29]

https://codereview.chromium.org/1397953005/diff/1/pkg/compiler/lib/src/cps_ir...
File pkg/compiler/lib/src/cps_ir/cps_ir_integrity.dart (left):

https://codereview.chromium.org/1397953005/diff/1/pkg/compiler/lib/src/cps_ir...
pkg/compiler/lib/src/cps_ir/cps_ir_integrity.dart:40: }
This is an unused function I left here by accident.

[sra1, 2015-10-15 23:06:52]

lgtm

https://chromiumcodereview.appspot.com/1397953005/diff/1/pkg/compiler/lib/src...
File pkg/compiler/lib/src/js_backend/codegen/task.dart (right):

https://chromiumcodereview.appspot.com/1397953005/diff/1/pkg/compiler/lib/src...
pkg/compiler/lib/src/js_backend/codegen/task.dart:193: if (cpsIntegrityChecker
== null) {
Is this worth it?

[asgerf, 2015-10-16 07:43:31]

https://chromiumcodereview.appspot.com/1397953005/diff/1/pkg/compiler/lib/src...
File pkg/compiler/lib/src/js_backend/codegen/task.dart (right):

https://chromiumcodereview.appspot.com/1397953005/diff/1/pkg/compiler/lib/src...
pkg/compiler/lib/src/js_backend/codegen/task.dart:193: if (cpsIntegrityChecker
== null) {
On 2015/10/15 23:06:52, sra1 wrote:
> Is this worth it?

It is necessary to ensure we get one instance per compiled method, and not one
instance per whole program or one per pass.

It would be cleaner to initialize it in the compile() method, but if we do it in
here, the class can be tree shaken and/or won't be parsed.

[asgerf, 2015-10-16 07:52:53]

Committed patchset #1 (id:1) manually as
1e23ef0cbb1d50f3225a29eadaaf31ffd51b3cdc (presubmit successful).