Implement bigint shift intrinsics on arm64.

Implement bigint shift intrinsics on arm64.

R=johnmccutchan@google.com

Committed: https://code.google.com/p/dart/source/detail?r=45521

[regis, 2015-05-04 15:36:16]

regis@google.com changed reviewers:
+ johnmccutchan@google.com

[Cutch, 2015-05-04 17:24:45]

lgtm

https://codereview.chromium.org/1124713003/diff/1/runtime/vm/intrinsifier_arm...
File runtime/vm/intrinsifier_arm64.cc (right):

https://codereview.chromium.org/1124713003/diff/1/runtime/vm/intrinsifier_arm...
runtime/vm/intrinsifier_arm64.cc:730: __ ldr(R0, Address(R7, -2 *
Bigint::kBytesPerDigit, Address::PreIndex));
Maybe a comment about Address::PreIndex altering R7? (here and elsewehre)

[regis, 2015-05-05 07:31:35]

Thanks!

https://codereview.chromium.org/1124713003/diff/1/runtime/vm/intrinsifier_arm...
File runtime/vm/intrinsifier_arm64.cc (right):

https://codereview.chromium.org/1124713003/diff/1/runtime/vm/intrinsifier_arm...
runtime/vm/intrinsifier_arm64.cc:730: __ ldr(R0, Address(R7, -2 *
Bigint::kBytesPerDigit, Address::PreIndex));
On 2015/05/04 17:24:45, Cutch wrote:
> Maybe a comment about Address::PreIndex altering R7? (here and elsewehre)

Using pre and post indexing is very common in loops on arm and arm64. I would
have to add comments to many places.

[regis, 2015-05-05 07:32:39]

Committed patchset #1 (id:1) manually as r45521 (presubmit successful).