Add Terminate operator.

Add Terminate operator.

Terminate is need for non-terminating loops (NTLs) that can appear after optimizing control flow. It gathers the control and effect(s) from a NTL and connects them to end so that they are not dead-code removed.

R=mstarzinger@chromium.org
BUG=

Committed: https://code.google.com/p/v8/source/detail?r=24812

[titzer, 2014-10-22 16:56:18]

On 2014/10/22 15:04:09, titzer wrote:

Added test, PTAL

[Michael Starzinger, 2014-10-22 17:07:27]

LGTM with one comment.

https://codereview.chromium.org/651843004/diff/40001/src/compiler/common-oper...
File src/compiler/common-operator.cc (right):

https://codereview.chromium.org/651843004/diff/40001/src/compiler/common-oper...
src/compiler/common-operator.cc:158: const Operator*
CommonOperatorBuilder::Terminate(int effects) {
nit: Can we drop the "effects" argument?

[titzer, 2014-10-22 17:15:15]

On 2014/10/22 17:07:27, Michael Starzinger wrote:
> LGTM with one comment.
> 
>
https://codereview.chromium.org/651843004/diff/40001/src/compiler/common-oper...
> File src/compiler/common-operator.cc (right):
> 
>
https://codereview.chromium.org/651843004/diff/40001/src/compiler/common-oper...
> src/compiler/common-operator.cc:158: const Operator*
> CommonOperatorBuilder::Terminate(int effects) {
> nit: Can we drop the "effects" argument?

Whoops, that was actually a bug. It should be an Operator1<int> and store the
number of incoming effects. Fixed.

[titzer, 2014-10-22 17:15:51]

Committed patchset #3 manually as 24812 (tree was closed).