[MIPS] Avoid using LA macro in inline assembly

[MIPS] Avoid using LA macro in inline assembly

LLVM's integrated assembler currently does not expand LA macro correctly
for PIC mode.
This change is replacing LA macro with appropriate instructions.

BUG=130022
TEST=Build Chromium with Clang and integrated as
TEST=Run sandbox_linux_unittests and components_browsertests

Committed: https://crrev.com/debc30a9ec8f98222193b102abc4d57fec915a83
Cr-Commit-Position: refs/heads/master@{#391527}

[lmilko, 2016-04-22 11:58:40]

milko.leporis@imgtec.com changed reviewers:
+ mdempsky@chromium.org, petar.jovanovic@imgtec.com

[lmilko, 2016-04-22 11:58:40]

Please take a look.

[petarj, 2016-04-22 13:25:12]

petarj@mips.com changed reviewers:
+ petarj@mips.com

[petarj, 2016-04-22 13:25:12]

lgtm but someone else must approve this as well, as I am not one of the owners.

[lmilko, 2016-04-28 10:23:21]

@mdempsky can you please take a look.

[mdempsky, 2016-04-28 16:02:13]

lgtm with nit

https://codereview.chromium.org/1908253003/diff/1/sandbox/linux/seccomp-bpf/s...
File sandbox/linux/seccomp-bpf/syscall.cc (right):

https://codereview.chromium.org/1908253003/diff/1/sandbox/linux/seccomp-bpf/s...
sandbox/linux/seccomp-bpf/syscall.cc:210: "lw     $v0, %got(2f)($gp)\n"
Please add a comment so someone doesn't come along and later try to helpfully
clean this up. E.g., explaining that this is equivalent to "la $v0, 2f", but LA
doesn't work with LLVM because of [insert link to LLVM bugzilla bug here].

[lmilko, 2016-05-04 15:13:05]

Uploaded new patch set.

https://codereview.chromium.org/1908253003/diff/1/sandbox/linux/seccomp-bpf/s...
File sandbox/linux/seccomp-bpf/syscall.cc (right):

https://codereview.chromium.org/1908253003/diff/1/sandbox/linux/seccomp-bpf/s...
sandbox/linux/seccomp-bpf/syscall.cc:210: "lw     $v0, %got(2f)($gp)\n"
On 2016/04/28 16:02:13, mdempsky wrote:
> Please add a comment so someone doesn't come along and later try to helpfully
> clean this up. E.g., explaining that this is equivalent to "la $v0, 2f", but
LA
> doesn't work with LLVM because of [insert link to LLVM bugzilla bug here].

Done.

[lmilko, 2016-05-04 15:14:08]

The CQ bit was checked by milko.leporis@imgtec.com

[lmilko, 2016-05-04 15:14:08]

The patchset sent to the CQ was uploaded after l-g-t-m from petarj@mips.com,
mdempsky@chromium.org
Link to the patchset: https://codereview.chromium.org/1908253003/#ps20001
(title: "Added comment regarding LA macro")

[commit-bot: I haz the power, 2016-05-04 15:14:22]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1908253003/20001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1908253003/20001

[commit-bot: I haz the power, 2016-05-04 16:12:47]

Committed patchset #2 (id:20001)

[commit-bot: I haz the power, 2016-05-04 16:13:59]

Description was changed from

==========
[MIPS] Avoid using LA macro in inline assembly

LLVM's integrated assembler currently does not expand LA macro correctly
for PIC mode.
This change is replacing LA macro with appropriate instructions.

BUG=130022
TEST=Build Chromium with Clang and integrated as
TEST=Run sandbox_linux_unittests and components_browsertests
==========

to

==========
[MIPS] Avoid using LA macro in inline assembly

LLVM's integrated assembler currently does not expand LA macro correctly
for PIC mode.
This change is replacing LA macro with appropriate instructions.

BUG=130022
TEST=Build Chromium with Clang and integrated as
TEST=Run sandbox_linux_unittests and components_browsertests

Committed: https://crrev.com/debc30a9ec8f98222193b102abc4d57fec915a83
Cr-Commit-Position: refs/heads/master@{#391527}
==========

[commit-bot: I haz the power, 2016-05-04 16:14:00]

Patchset 2 (id:??) landed as
https://crrev.com/debc30a9ec8f98222193b102abc4d57fec915a83
Cr-Commit-Position: refs/heads/master@{#391527}