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    <div class="moz-cite-prefix">I went ahead and replied to two of the
      review threads.  I only considered the parts which would be left
      without the native wrapped bitcode support.  <br>
      <br>
      Philip<br>
      <br>
      On 08/12/2015 01:24 PM, Teresa Johnson wrote:<br>
    </div>
    <blockquote
cite="mid:CAAe5K+XNe2D0KfgmQb_-r6gpcRTX1t7RxuJ29nPsMmjEoLp_8g@mail.gmail.com"
      type="cite">
      <div dir="ltr">I can remove the native wrapper portions of the
        associated patch and add that later. Most of the support as I
        mentioned is for the bitcode handling anyway, but I wanted to
        include a skeleton of the native wrapper part. For the RFC, I
        wanted to show the end goal including how the native wrapper
        support would look (it in fact mostly leverages the same bitcode
        encoding, so there isn't a lot of difference, and hence there
        isn't a whole lot of extra code needed to support that). The
        bulk of the RFC deals with the bitcode format, and I would love
        some feedback on that.
        <div><br>
        </div>
        <div>Thanks,</div>
        <div>Teresa<br>
          <div class="gmail_extra"><br>
            <div class="gmail_quote">On Wed, Aug 12, 2015 at 11:50 AM,
              Philip Reames <span dir="ltr"><<a
                  moz-do-not-send="true"
                  href="mailto:listmail@philipreames.com"
                  target="_blank">listmail@philipreames.com</a>></span>
              wrote:<br>
              <blockquote class="gmail_quote" style="margin:0 0 0
                .8ex;border-left:1px #ccc solid;padding-left:1ex">
                <div bgcolor="#FFFFFF" text="#000000">
                  <div>Alex already made what I consider to be the most
                    relevant point.  I would suggest removing the
                    unwanted functionality and asking again.  From my
                    perspective, native wrapped bitcode is only
                    interesting (and thus worth reviewing and/or talking
                    about) once the native bitcode version is in tree
                    and functional.  Frankly, I consider the native
                    wrapped bitcode to be an entirely orthogonal
                    proposal that shouldn't be tied to ThinLTO at all.  
                    <br>
                    <br>
                    Fair warning, I'm not going to be particularly
                    involved either way.  This is far enough from my own
                    immediate interests that I can't spare the cycles. 
                    I would suggest that you collaborate closely with
                    the Sony and Apple folks who are already *using* LTO
                    to find a proposal they're happy with.  Until you do
                    that, you are unlikely to make much progress.  <br>
                    <span><font color="#888888"> <br>
                        Philip</font></span>
                    <div>
                      <div><br>
                        <br>
                        On 08/12/2015 09:13 AM, Teresa Johnson wrote:<br>
                      </div>
                    </div>
                  </div>
                  <div>
                    <div>
                      <blockquote type="cite">
                        <div dir="ltr">
                          <div>Ping. Explicitly adding a few more people
                            who commented on the earlier (high-level)
                            ThinLTO RFC. I removed the body of the RFC
                            here since the original was large and had
                            trouble getting through the mailer. I also
                            updated the patch mentioned below so that it
                            was emailed to llvm-commits properly.<br>
                          </div>
                          <div><br>
                          </div>
                          <div>Thanks,</div>
                          <div>Teresa</div>
                          <div class="gmail_extra"><br>
                            <div class="gmail_quote">On Mon, Aug 3, 2015
                              at 11:59 AM, Teresa Johnson <span
                                dir="ltr"><<a moz-do-not-send="true"
                                  href="mailto:tejohnson@google.com"
                                  target="_blank">tejohnson@google.com</a>></span>
                              wrote:<br>
                              <blockquote class="gmail_quote"
                                style="margin:0 0 0 .8ex;border-left:1px
                                #ccc solid;padding-left:1ex">
                                <div dir="ltr">Hi Alex,
                                  <div><br>
                                  </div>
                                  <div>After outlining some of the
                                    rationale for using native-wrapped,
                                    there were a couple of responses
                                    that indicated native-wrapped
                                    support was reasonable, but they
                                    preferred to see bitcode-only first
                                    (Phillip and Rafael). This is
                                    essentially what this proposal and
                                    the patches do - I've implemented
                                    some of the basic support for
                                    looking for and parsing the
                                    native-wrapped sections, but the
                                    bitcode-only reading/writing support
                                    is more complete.</div>
                                  <div><br>
                                  </div>
                                  <div>In fact, as described in this
                                    RFC, I designed the native-wrapped
                                    format to utilize the same bitcode
                                    encoding for most of the ThinLTO
                                    information, so it uses most of the
                                    same underlying bitcode interfaces
                                    anyway. The additional support
                                    required for native-wrapped is not
                                    tremendous, and is similar to
                                    existing support in the LLVM tree
                                    for reading native-wrapped bitcode.</div>
                                  <div><br>
                                  </div>
                                  <div>We believe that there will be
                                    clang/llvm users who will find
                                    native-wrapped ThinLTO easier to use
                                    for the same reasons (e.g.
                                    compatibility with existing native
                                    toolchains), so I don't expect this
                                    to be Google specific.</div>
                                  <div><br>
                                  </div>
                                  <div>Thanks,</div>
                                  <div>Teresa</div>
                                </div>
                                <div>
                                  <div>
                                    <div class="gmail_extra"><br>
                                      <div class="gmail_quote">On Mon,
                                        Aug 3, 2015 at 12:26 PM, Alex
                                        Rosenberg <span dir="ltr"><<a
                                            moz-do-not-send="true"
                                            href="mailto:alexr@leftfield.org"
                                            target="_blank">alexr@leftfield.org</a>></span>
                                        wrote:<br>
                                        <blockquote class="gmail_quote"
                                          style="margin:0 0 0
                                          .8ex;border-left:1px #ccc
                                          solid;padding-left:1ex">
                                          <div dir="auto">
                                            <div>I think I've read all
                                              the feedback posted
                                              regarding your May
                                              proposal. I have yet to
                                              see a single response that
                                              wants native object
                                              wrapped bitcode.</div>
                                            <div><br>
                                            </div>
                                            <div>If the only use for
                                              native object wrapped
                                              bitcode is for your
                                              project at Google, then it
                                              probably shouldn't go into
                                              the tree against all of
                                              these objections.<br>
                                              <br>
                                              Alex</div>
                                            <div>
                                              <div><br>
                                                On Aug 3, 2015, at 9:19
                                                AM, Teresa Johnson <<a
                                                  moz-do-not-send="true"
href="mailto:tejohnson@google.com" target="_blank">tejohnson@google.com</a>>

                                                wrote:<br>
                                                <br>
                                              </div>
                                              <blockquote type="cite">
                                                <div dir="ltr">As
                                                  discussed in the
                                                  high-level ThinLTO
                                                  RFC <span
                                                    style="font-size:12.8000001907349px">(</span><a
moz-do-not-send="true"
                                                    href="http://lists.cs.uiuc.edu/pipermail/llvmdev/2015-May/086211.html"
style="font-size:12.8000001907349px" target="_blank">http://lists.cs.uiuc.edu/pipermail/llvmdev/2015-May/086211.html</a><span
style="font-size:12.8000001907349px">), we would like to add support for
                                                    native object
                                                    wrapped bitcode and
                                                    ThinLTO information.
                                                    Based on comments on
                                                    the mailing list, I
                                                    am adding support
                                                    for ThinLTO in both
                                                    normal bitcode
                                                    files, as well as
                                                    native-object
                                                    wrapped bitcode.</span>
                                                  <div><span
                                                      style="font-size:12.8000001907349px"><br>
                                                    </span></div>
                                                  <div><span
                                                      style="font-size:12.8000001907349px">The

                                                      following RFC
                                                      describes the
                                                      planned file
                                                      format of ThinLTO
                                                      information both
                                                      in the
                                                      bitcode-only and
                                                      native object
                                                      wrapped cases. It
                                                      doesn't yet define
                                                      the exact record
                                                      format, as I would
                                                      like feedback on
                                                      the overall block
                                                      design first.</span></div>
                                                  <div><span
                                                      style="font-size:12.8000001907349px"><br>
                                                    </span></div>
                                                  <div><span
                                                      style="font-size:12.8000001907349px">I've

                                                      also implemented
                                                      the support for
                                                      reading and
                                                      writing the
                                                      bitcode blocks in
                                                      the following
                                                      patch:</span></div>
                                                  <div><a
                                                      moz-do-not-send="true"
href="https://urldefense.proofpoint.com/v2/url?u=http-3A__reviews.llvm.org_D11722&d=AwMFaQ&c=8hUWFZcy2Z-Za5rBPlktOQ&r=Mfk2qtn1LTDThVkh6-oGglNfMADXfJdty4_bhmuhMHA&m=oUy_PB_mSfRgDO7H7bZOR04gv_DMzX5rPO_lv4PHt60&s=WVxrKkHnjKr75fCQ-UkGke8dk6KpZcFCnLWVrJ3G188&e="
                                                      rel="noreferrer"
                                                      style="font-size:12.8000001907349px"
                                                      target="_blank">http://reviews.llvm.org/D11722</a></div>
                                                  <div><br>
                                                  </div>
                                                  <div>The ThinLTO data
                                                    structures and the
                                                    file APIs are
                                                    described in a
                                                    separate RFC I will
                                                    be sending
                                                    simultaneously, with
                                                    pointers to the
                                                    patches implementing
                                                    them.</div>
                                                  <div><br>
                                                  </div>
                                                  <div>Looking forward
                                                    to your feedback.
                                                    Thanks!</div>
                                                  <div>Teresa</div>
                                                  <div><br>
                                                  </div>
                                                  <div><span>
                                                      <p dir="ltr"
style="line-height:1.38;margin-top:0pt;margin-bottom:0pt;text-align:center"><br>
                                                      </p>
                                                    </span></div>
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                            <div><br>
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                            -- <br>
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                                        nowrap="nowrap">Teresa Johnson |</td>
                                      <td
style="border-top-style:solid;border-top-color:rgb(51,105,232);border-top-width:2px"
                                        nowrap="nowrap"> Software
                                        Engineer |</td>
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style="border-top-style:solid;border-top-color:rgb(0,153,57);border-top-width:2px"
                                        nowrap="nowrap"> <a
                                          moz-do-not-send="true"
                                          href="mailto:tejohnson@google.com"
                                          target="_blank">tejohnson@google.com</a> |</td>
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style="border-top-style:solid;border-top-color:rgb(238,178,17);border-top-width:2px"
                                        nowrap="nowrap"> <a
                                          moz-do-not-send="true"
                                          href="tel:408-460-2413"
                                          value="+14084602413"
                                          target="_blank">408-460-2413</a></td>
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            -- <br>
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                        nowrap="nowrap">Teresa Johnson |</td>
                      <td
style="border-top-style:solid;border-top-color:rgb(51,105,232);border-top-width:2px"
                        nowrap="nowrap"> Software Engineer |</td>
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style="border-top-style:solid;border-top-color:rgb(0,153,57);border-top-width:2px"
                        nowrap="nowrap"> <a moz-do-not-send="true"
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                          target="_blank">tejohnson@google.com</a> |</td>
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