MIPS: Fix Sltu macro instruction.

MIPS: Fix Sltu macro instruction.

Fixes the case when the 'imm' is in range [8000,ffff], as the specification
says the 'imm' is sign-extended before the comparsion, so the effective range
is [max_unsigned-7fff,max_unsigned].

TEST=mjsunit/generated-transition-stub@3b8ad45e
BUG=

Committed: https://crrev.com/cb1084a800629bea10d88ba0cb0aad3d61ca5306
Cr-Commit-Position: refs/heads/master@{#39922}

[akos.palfi.imgtec, 2016-09-30 17:23:36]

Description was changed from

==========
MIPS: Fix Sltu macro instruction.

Fixes the case when the 'imm' is in range [8000,ffff], as the specification
says the 'imm' is sign-extended before the comparation, so the effective range
is [max_unsigned-7fff,max_unsigned].

TEST=mjsunit/generated-transition-stub@3b8ad45e
BUG=
==========

to

==========
MIPS: Fix Sltu macro instruction.

Fixes the case when the 'imm' is in range [8000,ffff], as the specification
says the 'imm' is sign-extended before the comparsion, so the effective range
is [max_unsigned-7fff,max_unsigned].

TEST=mjsunit/generated-transition-stub@3b8ad45e
BUG=
==========

[akos.palfi.imgtec, 2016-09-30 17:28:15]

akos.palfi@imgtec.com changed reviewers:
+ balazs.kilvady@imgtec.com, ilija.pavlovic@imgtec.com,
ivica.bogosavljevic@imgtec.com, marija.antic@imgtec.com, miran.karic@imgtec.com

[akos.palfi.imgtec, 2016-09-30 17:28:15]

PTAL.

[balazs.kilvady, 2016-09-30 17:37:46]

LGTM with small questions, nits. As it passes the new tests it must be fine :)

[balazs.kilvady, 2016-09-30 17:45:19]

https://codereview.chromium.org/2386673002/diff/20001/src/mips/macro-assemble...
File src/mips/macro-assembler-mips.cc (right):

https://codereview.chromium.org/2386673002/diff/20001/src/mips/macro-assemble...
src/mips/macro-assembler-mips.cc:1124: const uint32_t int16_min =
std::numeric_limits<int16_t>::min();
This should be in the else branch.

https://codereview.chromium.org/2386673002/diff/20001/src/mips/macro-assemble...
src/mips/macro-assembler-mips.cc:1133: sltiu(rd, rs,
static_cast<uint16_t>(rt.imm32_));
sltiu() expects int16 or uint16? Is this cast ok?

[akos.palfi.imgtec, 2016-09-30 17:55:10]

Fixed nits. PTAL.

https://codereview.chromium.org/2386673002/diff/20001/src/mips/macro-assemble...
File src/mips/macro-assembler-mips.cc (right):

https://codereview.chromium.org/2386673002/diff/20001/src/mips/macro-assemble...
src/mips/macro-assembler-mips.cc:1124: const uint32_t int16_min =
std::numeric_limits<int16_t>::min();
On 2016/09/30 17:45:19, balazs.kilvady wrote:
> This should be in the else branch.

Acknowledged.

https://codereview.chromium.org/2386673002/diff/20001/src/mips/macro-assemble...
src/mips/macro-assembler-mips.cc:1133: sltiu(rd, rs,
static_cast<uint16_t>(rt.imm32_));
On 2016/09/30 17:45:19, balazs.kilvady wrote:
> sltiu() expects int16 or uint16? Is this cast ok?

It expects int32. This casts [ffff8000, ffffffff] to [8000, ffff], I've checked
it with the debugger.

[akos.palfi.imgtec, 2016-09-30 17:58:08]

The CQ bit was checked by akos.palfi@imgtec.com

[akos.palfi.imgtec, 2016-09-30 17:58:09]

The patchset sent to the CQ was uploaded after l-g-t-m from
balazs.kilvady@imgtec.com
Link to the patchset: https://codereview.chromium.org/2386673002/#ps40001
(title: "Fix nits.")

[commit-bot: I haz the power, 2016-09-30 17:58:18]

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, 2016-09-30 18:28:39]

Description was changed from

==========
MIPS: Fix Sltu macro instruction.

Fixes the case when the 'imm' is in range [8000,ffff], as the specification
says the 'imm' is sign-extended before the comparsion, so the effective range
is [max_unsigned-7fff,max_unsigned].

TEST=mjsunit/generated-transition-stub@3b8ad45e
BUG=
==========

to

==========
MIPS: Fix Sltu macro instruction.

Fixes the case when the 'imm' is in range [8000,ffff], as the specification
says the 'imm' is sign-extended before the comparsion, so the effective range
is [max_unsigned-7fff,max_unsigned].

TEST=mjsunit/generated-transition-stub@3b8ad45e
BUG=
==========

[commit-bot: I haz the power, 2016-09-30 18:28:39]

Committed patchset #3 (id:40001)

[commit-bot: I haz the power, 2016-09-30 18:29:35]

Description was changed from

==========
MIPS: Fix Sltu macro instruction.

Fixes the case when the 'imm' is in range [8000,ffff], as the specification
says the 'imm' is sign-extended before the comparsion, so the effective range
is [max_unsigned-7fff,max_unsigned].

TEST=mjsunit/generated-transition-stub@3b8ad45e
BUG=
==========

to

==========
MIPS: Fix Sltu macro instruction.

Fixes the case when the 'imm' is in range [8000,ffff], as the specification
says the 'imm' is sign-extended before the comparsion, so the effective range
is [max_unsigned-7fff,max_unsigned].

TEST=mjsunit/generated-transition-stub@3b8ad45e
BUG=

Committed: https://crrev.com/cb1084a800629bea10d88ba0cb0aad3d61ca5306
Cr-Commit-Position: refs/heads/master@{#39922}
==========

[commit-bot: I haz the power, 2016-09-30 18:29:36]

Patchset 3 (id:??) landed as
https://crrev.com/cb1084a800629bea10d88ba0cb0aad3d61ca5306
Cr-Commit-Position: refs/heads/master@{#39922}