Make Bigint instances immutable by removing all setters.

Make Bigint instances immutable by removing all setters.
This required rewriting a large portion of bigint.dart.

R=rmacnak@google.com

Committed: https://code.google.com/p/dart/source/detail?r=43492

[regis, 2015-01-17 00:36:37]

regis@google.com changed reviewers:
+ iposva@google.com, rmacnak@google.com

[regis, 2015-01-17 00:36:37]

Unfortunately, RSA is slower with this cl, so I will not commit this change yet.
I'll profile and put more work into it, but feel free to have a look at where
it's going.

Thanks,
Regis

[regis, 2015-02-03 21:18:48]

PTAL

The lost performance has been regained.

Thanks,
Regis

[rmacnak, 2015-02-04 19:24:53]

https://codereview.chromium.org/842033005/diff/40001/runtime/lib/bigint.dart
File runtime/lib/bigint.dart (right):

https://codereview.chromium.org/842033005/diff/40001/runtime/lib/bigint.dart#...
runtime/lib/bigint.dart:41: class _Bigint extends _IntegerImplementation
implements int {
It would be nice to have a comment saying Bigints are represented by sign +
32-bit digits in little endian order, rational of the leading zero digit, etc.

https://codereview.chromium.org/842033005/diff/40001/runtime/lib/bigint.dart#...
runtime/lib/bigint.dart:56: // Note: Not declared as final in order to satisfy
optimizer, which expects
Optimizer is unhappy with final or just const? These should be at least final if
possible, and made private if not.

https://codereview.chromium.org/842033005/diff/40001/runtime/lib/bigint.dart#...
runtime/lib/bigint.dart:110: while (n < length) {
Typed data is zero initialized.

https://codereview.chromium.org/842033005/diff/40001/runtime/lib/bigint.dart#...
runtime/lib/bigint.dart:713: var neg = _neg;
tabs

[regis, 2015-02-04 22:06:23]

PTAL

Thanks!

https://codereview.chromium.org/842033005/diff/40001/runtime/lib/bigint.dart
File runtime/lib/bigint.dart (right):

https://codereview.chromium.org/842033005/diff/40001/runtime/lib/bigint.dart#...
runtime/lib/bigint.dart:41: class _Bigint extends _IntegerImplementation
implements int {
On 2015/02/04 19:24:53, rmacnak wrote:
> It would be nice to have a comment saying Bigints are represented by sign +
> 32-bit digits in little endian order, rational of the leading zero digit, etc.

Done.

https://codereview.chromium.org/842033005/diff/40001/runtime/lib/bigint.dart#...
runtime/lib/bigint.dart:56: // Note: Not declared as final in order to satisfy
optimizer, which expects
On 2015/02/04 19:24:53, rmacnak wrote:
> Optimizer is unhappy with final or just const? These should be at least final
if
> possible, and made private if not.

It's unhappy with final or const. I cannot make it const, since the expression
is not const. I made it private though, as well as all other constants.

https://codereview.chromium.org/842033005/diff/40001/runtime/lib/bigint.dart#...
runtime/lib/bigint.dart:110: while (n < length) {
On 2015/02/04 19:24:53, rmacnak wrote:
> Typed data is zero initialized.

Good point. Removed initialization here and at other places.

https://codereview.chromium.org/842033005/diff/40001/runtime/lib/bigint.dart#...
runtime/lib/bigint.dart:713: var neg = _neg;
On 2015/02/04 19:24:53, rmacnak wrote:
> tabs

Done.

[rmacnak, 2015-02-04 23:49:14]

LGTM

https://codereview.chromium.org/842033005/diff/60001/runtime/lib/bigint.dart
File runtime/lib/bigint.dart (right):

https://codereview.chromium.org/842033005/diff/60001/runtime/lib/bigint.dart#...
runtime/lib/bigint.dart:41: // A big integer number is represented by a sign, an
array of 32-bit unsigned
Nice!

[regis, 2015-02-04 23:56:50]

Committed patchset #4 (id:60001) manually as r43492 (presubmit successful).