Revert of MIPS: Fix bad RegisterConfiguration usage in InstructionSequence unit tests.

Revert of MIPS: Fix bad RegisterConfiguration usage in InstructionSequence unit tests. (patchset #3 id:40001 of https://codereview.chromium.org/2433093002/ )

Reason for revert:
This change rendered InstructionSequenceTest::SetNumRegs ineffectual, thus
loosening the tests that were using that API to ensure correct register
allocation under intentionally constrained setups. 

For the problem stated in this CL, a solution needs to continue supporting the
intentionally set-up test configuration.

Original issue's description:
> MIPS: Fix bad RegisterConfiguration usage in InstructionSequence unit tests.
> 
> Test InstructionSequenceTest has been initialized with a testing RegisterConfiguration
> instance defined in instruction-sequence-unittest.h, whereas class ExplicitOperand which
> is being tested used RegisterConfiguration from instruction.cc. In case these two
> instances are different, the tests would fail. The issue is fixed by using the same
> instance of RegisterConfiguration both for test code and code under test.
> 
> Additionally, the tests in register-allocator-unittest.cc use hardcoded values
> for register and begin failing is the hardcoded register is not available for
> allocation. Fix by forcing the use of allocatable registers only.
> 
> TEST=unittests.MoveOptimizerTest.RemovesRedundantExplicit,unittests.RegisterAllocatorTest.SpillPhi
> BUG=
> 
> Committed: https://crrev.com/0cf56232209d4c9c669b8426680de18806f6c29a
> Cr-Commit-Position: refs/heads/master@{#40862}

TBR=dcarney@chromium.org,bmeurer@chromium.org,mstarzinger@chromium.org,vogelheim@chromium.org,titzer@chromium.org,ivica.bogosavljevic@imgtec.com
# Not skipping CQ checks because original CL landed more than 1 days ago.
BUG=

Review-Url: https://codereview.chromium.org/2587593002
Cr-Commit-Position: refs/heads/master@{#41777}
Committed: https://chromium.googlesource.com/v8/v8/+/8e833623e94b95b8906a8d92799d8d998ca72ee6

[Mircea Trofin, 2016-12-16 22:41:50]

The CQ bit was checked by mtrofin@chromium.org

[Mircea Trofin, 2016-12-16 22:41:50]

Created Revert of MIPS: Fix bad RegisterConfiguration usage in
InstructionSequence unit tests.

[commit-bot: I haz the power, 2016-12-16 22:42:05]

CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2016-12-16 23:09:34]

CQ is committing da patch.

Bot data: {"patchset_id": 1, "attempt_start_ts": 1481928110369640, "parent_rev":
"61833f5b9adfc3a19653c37cf27135a373474458", "commit_rev":
"8e833623e94b95b8906a8d92799d8d998ca72ee6"}

[commit-bot: I haz the power, 2016-12-16 23:09:40]

Description was changed from

==========
Revert of MIPS: Fix bad RegisterConfiguration usage in InstructionSequence unit
tests. (patchset #3 id:40001 of https://codereview.chromium.org/2433093002/ )

Reason for revert:
This change rendered InstructionSequenceTest::SetNumRegs ineffectual, thus
loosening the tests that were using that API to ensure correct register
allocation under intentionally constrained setups. 

For the problem stated in this CL, a solution needs to continue supporting the
intentionally set-up test configuration.

Original issue's description:
> MIPS: Fix bad RegisterConfiguration usage in InstructionSequence unit tests.
> 
> Test InstructionSequenceTest has been initialized with a testing
RegisterConfiguration
> instance defined in instruction-sequence-unittest.h, whereas class
ExplicitOperand which
> is being tested used RegisterConfiguration from instruction.cc. In case these
two
> instances are different, the tests would fail. The issue is fixed by using the
same
> instance of RegisterConfiguration both for test code and code under test.
> 
> Additionally, the tests in register-allocator-unittest.cc use hardcoded values
> for register and begin failing is the hardcoded register is not available for
> allocation. Fix by forcing the use of allocatable registers only.
> 
>
TEST=unittests.MoveOptimizerTest.RemovesRedundantExplicit,unittests.RegisterAllocatorTest.SpillPhi
> BUG=
> 
> Committed: https://crrev.com/0cf56232209d4c9c669b8426680de18806f6c29a
> Cr-Commit-Position: refs/heads/master@{#40862}

TBR=dcarney@chromium.org,bmeurer@chromium.org,mstarzinger@chromium.org,vogelh...
# Not skipping CQ checks because original CL landed more than 1 days ago.
BUG=
==========

to

==========
Revert of MIPS: Fix bad RegisterConfiguration usage in InstructionSequence unit
tests. (patchset #3 id:40001 of https://codereview.chromium.org/2433093002/ )

Reason for revert:
This change rendered InstructionSequenceTest::SetNumRegs ineffectual, thus
loosening the tests that were using that API to ensure correct register
allocation under intentionally constrained setups. 

For the problem stated in this CL, a solution needs to continue supporting the
intentionally set-up test configuration.

Original issue's description:
> MIPS: Fix bad RegisterConfiguration usage in InstructionSequence unit tests.
> 
> Test InstructionSequenceTest has been initialized with a testing
RegisterConfiguration
> instance defined in instruction-sequence-unittest.h, whereas class
ExplicitOperand which
> is being tested used RegisterConfiguration from instruction.cc. In case these
two
> instances are different, the tests would fail. The issue is fixed by using the
same
> instance of RegisterConfiguration both for test code and code under test.
> 
> Additionally, the tests in register-allocator-unittest.cc use hardcoded values
> for register and begin failing is the hardcoded register is not available for
> allocation. Fix by forcing the use of allocatable registers only.
> 
>
TEST=unittests.MoveOptimizerTest.RemovesRedundantExplicit,unittests.RegisterAllocatorTest.SpillPhi
> BUG=
> 
> Committed: https://crrev.com/0cf56232209d4c9c669b8426680de18806f6c29a
> Cr-Commit-Position: refs/heads/master@{#40862}

TBR=dcarney@chromium.org,bmeurer@chromium.org,mstarzinger@chromium.org,vogelh...
# Not skipping CQ checks because original CL landed more than 1 days ago.
BUG=

Review-Url: https://codereview.chromium.org/2587593002
Cr-Commit-Position: refs/heads/master@{#41777}
Committed:
https://chromium.googlesource.com/v8/v8/+/8e833623e94b95b8906a8d92799d8d998ca...
==========

[commit-bot: I haz the power, 2016-12-16 23:09:40]

Committed patchset #1 (id:1) as
https://chromium.googlesource.com/v8/v8/+/8e833623e94b95b8906a8d92799d8d998ca...