Subzero: Update the lowering documentation.

Subzero: Update the lowering documentation.

BUG= none
R=jvoung@chromium.org

Committed: https://gerrit.chromium.org/gerrit/gitweb?p=native_client/pnacl-subzero.git;a=commit;h=3018545a211f4204525886329d556acc656c4c41

[Jim Stichnoth, 2015-01-10 00:17:37]

stichnot@chromium.org changed reviewers:
+ jvoung@chromium.org

[jvoung (off chromium), 2015-01-10 01:08:04]

Nice to see that overall, things are simpler

https://codereview.chromium.org/846763002/diff/1/LOWERING.rst
File LOWERING.rst (right):

https://codereview.chromium.org/846763002/diff/1/LOWERING.rst#newcode141
LOWERING.rst:141: ``Variable`` whose live range that spans the ``call``
instruction.  ICE provides
drop the "that" in "whose live range that spans"?

https://codereview.chromium.org/846763002/diff/1/LOWERING.rst#newcode214
LOWERING.rst:214: InstFakeKill(eax, ecx, edx)
This syntax for InstFakeKill seems to be the old style, but this section also
seems to overlap a bit with the InstFakeDef description on line 178?

[Jim Stichnoth, 2015-01-10 16:19:20]

https://codereview.chromium.org/846763002/diff/1/LOWERING.rst
File LOWERING.rst (right):

https://codereview.chromium.org/846763002/diff/1/LOWERING.rst#newcode141
LOWERING.rst:141: ``Variable`` whose live range that spans the ``call``
instruction.  ICE provides
On 2015/01/10 01:08:04, jvoung wrote:
> drop the "that" in "whose live range that spans"?

Done.

https://codereview.chromium.org/846763002/diff/1/LOWERING.rst#newcode214
LOWERING.rst:214: InstFakeKill(eax, ecx, edx)
On 2015/01/10 01:08:04, jvoung wrote:
> This syntax for InstFakeKill seems to be the old style, but this section also
> seems to overlap a bit with the InstFakeDef description on line 178?

Yeah, I had left the explicit register list in this "pseudocode" just for
documentation purposes.  I moved the documentation into a "comment".

The section title is "Preventing dead-code elimination", but this example was
given as a contrast, if you want to *allow* dead-code elimination in certain
cases.  Hopefully I improved this confusion by changing the section title to
"Managing dead-code elimination".

[jvoung (off chromium), 2015-01-12 16:48:23]

lgtm

[Jim Stichnoth, 2015-01-12 17:00:05]

Committed patchset #2 (id:20001) manually as
3018545a211f4204525886329d556acc656c4c41 (presubmit successful).