<div dir="ltr"><div dir="ltr"><div class="gmail_default" style="font-family:monospace;font-size:small;color:#000000">FYI you can also view the RFC here <span style="font-family:Arial,Helvetica,sans-serif;color:rgb(34,34,34)"><a href="https://groups.google.com/g/llvm-dev/c/h1DvHguLpxU">https://groups.google.com/g/llvm-dev/c/h1DvHguLpxU</a> , which displays the diagrams better (without extra wide space).</span></div><div class="gmail_default" style="font-family:monospace;font-size:small;color:#000000"><span style="font-family:Arial,Helvetica,sans-serif;color:rgb(34,34,34)"><br></span></div><div class="gmail_default" style="font-family:monospace;font-size:small;color:#000000"><span style="font-family:Arial,Helvetica,sans-serif;color:rgb(34,34,34)">David</span></div><div class="gmail_default" style="font-family:monospace;font-size:small;color:#000000"><span style="font-family:Arial,Helvetica,sans-serif;color:rgb(34,34,34)"><br></span></div></div><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Wed, Sep 29, 2021 at 3:17 PM Snehasish Kumar <<a href="mailto:snehasishk@google.com">snehasishk@google.com</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><div dir="ltr"><div style="font-size:small"><span style="background-color:transparent;color:rgb(0,0,0);white-space:pre-wrap;font-family:monospace;font-size:x-small">This RFC contains the following:</span><br></div><div style="font-size:small"><span style="background-color:transparent;color:rgb(0,0,0);white-space:pre-wrap;font-family:monospace;font-size:x-small"><br></span></div><div class="gmail_quote"><div><font face="monospace" size="1"><span id="gmail-m_-9106505476671694967m_2146366273326536719gmail-docs-internal-guid-adb1afcf-7fff-1ad0-257d-166b0bf60e46"><p dir="ltr" style="line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">* Proposal to introduce a new raw binary serialization format for heap allocation profiles</span></p><p dir="ltr" style="line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">* Proposal to extend the <span class="gmail_default" style="font-size:small"></span><span class="gmail_default">PGO </span><span class="gmail_default" style="font-size:small"></span>indexed format to hold heap allocation profiles</span></p><span class="gmail_default">We look forward to your feedback on the proposals.</span><span class="gmail_default" style="font-size:small"></span></span></font></div><div><font face="monospace"><span class="gmail_default"></span></font><span class="gmail_default" style="color:rgb(0,0,0);font-family:monospace;white-space:pre-wrap"></span></div><div><span style="color:rgb(0,0,0);font-family:monospace;font-size:x-small;white-space:pre-wrap">Authors: </span><span style="color:rgb(0,0,0);font-family:monospace;font-size:x-small;white-space:pre-wrap"><a href="mailto:snehasishk@google.com" target="_blank">snehasishk@google.com</a></span><span style="color:rgb(0,0,0);font-family:monospace;font-size:x-small;white-space:pre-wrap">, </span><span style="color:rgb(0,0,0);font-family:monospace;font-size:x-small;white-space:pre-wrap"><a href="mailto:davidxl@google.com" target="_blank">davidxl@google.com</a></span><span style="color:rgb(0,0,0);font-family:monospace;font-size:x-small;white-space:pre-wrap">, </span><span style="color:rgb(0,0,0);font-family:monospace;font-size:x-small;white-space:pre-wrap"><a href="mailto:tejohnson@google.com" target="_blank">tejohnson@google.com</a></span><span style="color:rgb(0,0,0);font-family:monospace;font-size:x-small;white-space:pre-wrap"> </span><span style="font-family:monospace"></span><br></div><div><font face="monospace"><br><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">Introduction</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">—-----------</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">The design of a sanitizer-based heap profiler (MemProf) was shared with llvm-dev in Jun 2020 [1]. Since then Teresa (@tejohnson) has added a sanitizer based heap profiler which can be enabled with -fmemory-profile. Today it writes out the data in a text format which can be inspected by users. We have used this to drive analyses of heap behaviour at Google. This RFC shares details on a binary serialization format for heap profiling data which can then be reused by the compiler to guide optimizations similar to traditional PGO. </span></p><br><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">Similar to the existing instrumentation based PGO, the binary heap profile data for PGHO has two forms. One is the raw data format that is used by the profiler runtime, and the other is the indexed profile format used by the compiler. The profile data with the indexed profile data format will be generated by llvm-profdata from the raw profile data offline. This allows a single binary profile file to hold the PGO and Memprof profiling data. Fig 1 below shows the binary format generation and use.</span></p><br><br><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">  ┌──────────────────┐ Raw Profile ┌───────────────┐     Indexed Profile (v8)     </span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">  │ Compiler Runtime ├─────────────► llvm-profdata ├───► with Memprof data ───► -fprofile-use</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">  └──────────────────┘             └───────────────┘</span></p><br><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">Fig 1: Memprof binary profile lifecycle</span></p><br><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">Raw Binary Format</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">—----------------</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">The raw binary format contains 4 sections</span></p><br><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">1. Memprof raw profile header</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">2. Memory mapping layout</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">3. Memory Info Block (MIB) records</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">4. Call stack information</span></p><br><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">          +----------------------+</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">          |  Magic               |</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">          +----------------------+   H</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">          |  Version             |   E</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">          +----------------------+   A</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">          |  Total Size          |   D      </span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">          +----------------------+   E      </span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">+---------|  Map Offset          |   R</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">|         +----------------------+   </span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">|   +-----|  MIB Offset          |   </span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">|   |     +----------------------+   </span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">|   |     |  Call Stack Offset   |---------+</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">|   |     +----------------------+         |</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">+-------->|  Number of           |   M     |</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">    |     |  Map Entries         |   A     |</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">    |     +----------------------+   P     |         </span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">    |     |                      |         |</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">    |     |  Map Entry           |   S     |</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">    |     +----------------------+   E     |</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">    |     |    ...               |   C     |</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">    |     +----------------------+   T     |</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">    |     |                      |   I     |</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">    |     |  Map Entry           |   O     |</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">    |     +----------------------+   N     |</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">    |                                      |</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">    |                                      |</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">    |     +----------------------+         |</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">    +---->|   Number of          |   M     |</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">          |   MIB Entries        |   I     |</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">          +----------------------+   B     |         </span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">          |                      |         |</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">          |   MIB Entry          |   S     |</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">          +----------------------+   E     |</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">          |    ...               |   C     |</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">          +----------------------+   T     |</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">          |                      |   I     |</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">          |   MIB Entry          |   O     |</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">          +----------------------+   N     |</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">                                           |</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">          +----------------------+         |</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">          |   Number of          |<--------+</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">          |   Call Stack Entries |  S  S</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">          +----------------------+  T  E</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">          |   Call Stack Entry   |  A  C</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">          +----------------------+  C  T</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">          |   ...                |  K  I</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">          +----------------------+     O</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">          |   Call Stack Entry   |     N</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">          +----------------------+</span></p><br><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">Fig 2: Memprof Raw Format</span></p><br><br><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">* Memprof raw profile header</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">The header consists of a unique identifier, version number, total size of the profile as well as offset into the profile for each of the following sections - memory mapping layout, memprof profile entries and call stack information. We do not intend to maintain backwards compatibility for the raw binary format.</span></p><br><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">* Memory mapping layout</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">The process memory mappings for the executable segment during profiling are stored in this section. This allows symbolization during post processing for binaries which are built with position independent code. For now all read only, executable  mappings are recorded, however in the future, mappings for heap data can also potentially be stored. For each mapping, we record</span></p><ul style="font-size:x-small;margin-top:0px;margin-bottom:0px"><li dir="ltr" style="list-style-type:disc;color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap"><p dir="ltr" style="line-height:1.38;margin-top:0pt;margin-bottom:0pt" role="presentation"><span style="background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">Start (virtual address)</span></p></li><li dir="ltr" style="list-style-type:disc;color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap"><p dir="ltr" style="line-height:1.38;margin-top:0pt;margin-bottom:0pt" role="presentation"><span style="background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">End (virtual address)</span></p></li><li dir="ltr" style="list-style-type:disc;color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap"><p dir="ltr" style="line-height:1.38;margin-top:0pt;margin-bottom:0pt" role="presentation"><span style="background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">Offset (from the file it was mmap-ed from)</span></p></li><li dir="ltr" style="list-style-type:disc;color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap"><p dir="ltr" style="line-height:1.38;margin-top:0pt;margin-bottom:0pt" role="presentation"><span style="background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">buildId (linker generated hash -Wl,build-id</span></p></li></ul><br><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">*  MIB Records</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">The profile information we collect is currently defined in [2]. The section begins with a 8 byte entry containing the number of profile entries in this section. Each entry is uniquely identified by the dynamic calling context of the allocation site. For each entry, various metrics such as access counts, allocation sizes, object lifetimes etc are computed via profiling. This section may contain multiple entries identified by the same callstack id. Subsequent processing to convert and merge multiple raw profiles will deduplicate any such entries.</span></p><br><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">* Call stack information</span><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap"><br></span><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">Each memprof profile entry is uniquely identified by its dynamic calling context. In this section we record the identifier and its corresponding call stack trace. We use the sanitizer stack depot provided identifier and serialize the trace for each without deduplication. The section begins with a 8b entry containing the number of call stack entries. Each call stack entry contains a 8b field which denotes how many contexts are recorded in this entry. Each frame is identified by an 8b program counter address which holds the call instruction virtual address - 1. Further deduplication is possible though we do not do so at this time.</span></p><br><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">* Raw Profile Characteristics</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">To understand the characteristics of raw binary profiles generated by Memprof, we experimented with a clang bootstrap build. We ran 500 invocations of Memprof-instrumented clang on clang source code. Each invocation produced a raw binary profile and we present some aggregate information about them below:</span></p><br><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">+---------------------------------+--------+---------+---------+</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">|                                 | Min    | Median  | Max     |</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">+---------------------------------+--------+---------+---------+</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">| Unique allocation contexts      | 940    | 10661   | 35355   |</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">+---------------------------------+--------+---------+---------+</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">| MIB records size (bytes)        | 101528 | 1151396 | 3818348 |</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">+---------------------------------+--------+---------+---------+</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">| Call stack section size (bytes) | 31080  | 419048  | 1439144 |</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">+---------------------------------+--------+---------+---------+</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">| Total Size (bytes)              | 133336 | 1571680 | 5258220 |</span></p><p dir="ltr" style="font-size:x-small;line-height:1.2;margin-top:5pt;margin-bottom:5pt"><span style="color:rgb(0,0,0);font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">+---------------------------------+--------+---------+---------+</span></p><br><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">The size of the header is 48 bytes and the number of read only executable memory maps is usually small (12 in this case) with each map entry consuming 64 bytes. We find that the raw profiles are highly compressible, on average files are compressed by 81%. The largest raw profile in the dataset is ~5M in size. It is compressed to 975K using zip on default settings. In contrast for the same clang build, the instrumented PGO raw profile is ~21M in size (zip compressed 73%). Note that the Memprof profile size is proportional to the number of allocation contexts during profiling.  </span></p><br><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">Since these are profiles from individual invocations, they must be merged before use. This is performed implicitly during the conversion to indexed profile format by llvm-profdata. MIBs are merged based on their call stack.</span></p><br><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">Memprof extensions for the indexed profile format</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">—------------------------------------------------</span></p><br><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">+----------------+</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">|   MAGIC        |</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">+----------------+</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">|   VERSION      |</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">+----------------+</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">|   HASHTYPE     |</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">+--+----------+--+</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">|HASHTAB OFFSET  |-------+</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">+--+----------+--+       |</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">+----------------+       |</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">|                |       |</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">|  PROFILE       |       |</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">|  SUMMARY       |       |</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">|  DATA          |       |</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">+----------------+       |</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">+----------------+ <----+</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">|                |</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">|   OnDisk       |</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">|   Chained      |</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">|   HashTable    |</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">|                |</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">+----------------+</span></p><br><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">Fig 3: Existing PGO indexed profile format</span></p><br><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">During the offline processing step (using llvm-profdata), allocation contexts are pruned and merged. The end result is a collection of unique allocation contexts with access, size and lifetime properties. Contexts are uniquely identified based on the call stack and are stored using a prefix deduplication scheme described in Section “Symbolized Memprof call stack section”.</span></p><br><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">To fit into the PGO profile format, we need to index the profile using the function name. The only functions that own Memprof profile data are those direct callers of the allocator primitive functions. Thus the profile data mapping in the IR must account for potentially missing frames. Implications on matching of the profile data with the IR is touched upon in Section “Profile Data matching in IR” and will be further detailed in an upcoming RFC. </span></p><br><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">The Memprof profile data for a particular function can then be just an array of MIB entries. One allocation site in the function can have multiple MIB entries each one of them corresponding to one allocation context.</span></p><br><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">The change to the existing PGO indexed format is summarized as:</span></p><ul style="font-size:x-small;margin-top:0px;margin-bottom:0px"><li dir="ltr" style="list-style-type:disc;color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap"><p dir="ltr" style="line-height:1.38;margin-top:0pt;margin-bottom:0pt" role="presentation"><span style="background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">Augment the profile record data structure to include an optional MIB array after the value profile data [3].</span></p></li><li dir="ltr" style="list-style-type:disc;color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap"><p dir="ltr" style="line-height:1.38;margin-top:0pt;margin-bottom:0pt" role="presentation"><span style="background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">Add one additional section before the existing OnDiskChainedHashtable to store the allocation stacks (referenced by the MIBs). This section is after the profile summary data section [4].</span></p></li><li dir="ltr" style="list-style-type:disc;color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap"><p dir="ltr" style="line-height:1.38;margin-top:0pt;margin-bottom:0pt" role="presentation"><span style="background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">Bump the version number.</span></p></li></ul><br><br><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">Memprof portable entry format</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">—----------------------------</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">The raw memprof profile entry format is subject to change with version. However, the indexed profile entry must be backwards compatible to ensure that the PGO profile as a whole is backwards compatible. We propose a schema based format - per function description of a Memprof profile entry. Each field is identified by a tag. We propose the following schema:</span></p><br><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">struct MIBMeta {</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">       enum MIBFieldTag {</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">          // The tag ids remain unchanged. </span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">          Unused = 0, </span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">          StackID = 1,</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">          AllocCount = 2,</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">          AveSize = 3,</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">          MinSize = 4,</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">          MaxSize = 5,</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">          AveAccessCount = 6,</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">          MinAccessCount = 7,</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">          MaxAccessCount = 8,</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">          AveLifetime = 9,</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">          MinLifetime = 10,</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">          MaxLifetime = 11,</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">          NumMigration = 12,</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">          NumLifetimeOverlaps = 13,</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">          NumSameAllocCPU = 14,</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">          NumSameDeallocCPU = 15</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">       };</span></p><br><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">       enum MIBFieldType {</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">         Unused = 0,</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">         UINT8 = 1,</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">         UINT16 = 2,</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">         UINT32 = 3,      // Varint encoded</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">         UINT64 = 4,      // Varint encoded</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">      };</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">};</span></p><br><br><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">// Mapping of tags to their descriptive names</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">const char *MIBFieldName[] = {</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">        "",</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">        "StackID", </span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">        "AllocCount",</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">         …</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">        "NumSameDeallocCPU"</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">};</span></p><br><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">// Mapping of tags to their types</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">uint8 MIBFieldType []  = {</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">         0, // unused</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">         MIBMeta::MIBFieldType::UINT64,</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">            ….</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">};</span></p><br><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">To make the field tag, field name, and field type declarations always in sync, a shared .inc file will be used. This file will be shared between compiler-rt and llvm/lib/ProfileData libraries. Dependencies across the compiler-rt project are not recommended for isolation.</span></p><br><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">// MIBDef.inc file</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">// define  MIBEntryDef(tag, name, type) before inclusion</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">MIBEntryDef(StackID = 1, "StackID",</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">            MIBMeta::MIBFieldType::UINT64)</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">MIBEntryDef(AllocCount = 2, "AllocCount",  </span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">            MIBMeta::MIBFieldType::UINT32)</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">...</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">MIBEntryDef(NumSameDeallocCPU=13,"NumSameDeallocCPU",    </span><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap"><span style="width:100px;display:inline-block"></span></span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">            MIBMeta::MIBFieldType:UINT8)</span></p><br><br><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">enum MIBFieldTag {</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">   StartTag = 0,</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">   #define MIBEntryDef(tag, name, type) tag</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">   #include "MIBDef.inc"</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">   #undef MIBEntryDef</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">};</span></p><br><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">const char *MIBFieldName {</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">    #define MIBEntryDef(tag, name, type) name</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">    "",</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">    #include "MIBEntryDef.inc"</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">    #undef MIBEntryDef</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">};</span></p><br><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">uint8 MIBFieldType {</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">   #define MIBEntryDef(tag, name, type) type</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">   0, // not used</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">   #include "MIBEntryDef.inc"</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">   #undef MIBDefEntry</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">};</span></p><br><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">The InstrProfRecord for each function will hold the schema and an array of Memprof info blocks, one for each unique allocation context.</span></p><br><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">Symbolized Memprof call stack section </span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">—------------------------------------</span><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap"><br><br></span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">This section holds the symbolized version of the call stack section in the raw profile. This is necessary to enable the compiler to map recorded runtime PC addresses to source locations during recompilation. For space efficiency, this section is split into three subsections: 1. stack entry table 2. file path table 3. string table.</span><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap"><br><br></span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">Fig 4 shows the relationship between the three tables.</span></p><br><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">     STACK ENTRY        FILE PATH         STRING</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">        TABLE             TABLE           TABLE</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">     ┌────────┐        ┌──┬──┬──┐       ┌─────────┐</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">     │        │        │  │  │  │       │10 abc   │</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">     │        │        ├──┼──┼──┤       ├─────────┤</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">     │        │        │  │  │  │◄┐     │11 def   │</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">     │        │        ├──┼──┼──┤ │     ├─────────┤</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">     ├──┬──┬──┤        │  │  │  │ │     │12 ghi   │</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap"> ┌───┤03│LN│DI│        ├──┼──┼──┤ │     ├─────────┤</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap"> │   ├──┴──┴──┤   ┌───►│03│13│01├─┘  ┌─►│13 XY.h  │</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap"> │   └────────┘   │    └──┴─┬┴──┘    │  └─────────┘</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap"> │                │         │        │</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap"> └────────────────┘         └────────┘</span></p><br><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">Fig 4. The Stack Entry, File Path and String Table. </span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">       LN = Line Number, DI = Discriminator</span></p><br><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">* Stack Entry Table: Each uniquely identified symbolized call stack consists of a variable number of callsites. In the indexed format, each callsite needs to be represented as file:line:discriminator (as shown in Fig 4). The call stack location is a 64-bit field, but it is split into three subfields: file table index, line number, and the discriminator value. The file table index is a pointer to a leaf node in the prefix encoded scheme described below.</span></p><br><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">* File path table using prefix encoding: Full path filenames have lots of common substrings due to the directory structure so they can be compressed. One simple scheme is to use the reverse prefix tree representation. In this representation, the name string of a directory at each level (not including prefixes) is represented by a node, and it is linked to its parent node. To summarize, the file path table is represented as an array of nodes organized as a forest of reversed tree structures. </span></p><br><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">For instance, the strings </span><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap"><br></span><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">“abc/def/ghi/XY.c”,  </span><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap"><br></span><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">“abc/def/ghi/XY.h”, </span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">“abc/def/jkl/UV.c” </span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">are represented as </span></p><br><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">             +-----------+<------+</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">             |  abc      |       |</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">+----->+---->+-----------+       |</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">|      |     |  def      +-------+</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">|      |     +-----------+</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">|      +-----+  ghi      |<-------+----+</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">|            +-----------+        |    |</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">+-+--------->|  jkl      |        |    |</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">  |          +-----------+        |    |   </span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">  |          |  XY.c     +--------+    |</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">  |          +-----------+             |</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">  +----------+  UV.c     |             |</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">             +-----------+             |</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">             |  XY.h     +-------------+</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">             +-----------+      </span></p><br><br><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">Fig 5. Prefix tree representation of paths in the file path table</span></p><br><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">Each parent link implies a path separator ‘/’. Furthermore we represent each file or directory string as an integer offset into the string table (see Fig 4). Thus each node holds an offset into the string table and a pointer to the parent (interior) directory node.</span></p><br><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">* String table: To remove redundancies across prefix tree nodes in the file path encoding, we use a string table which stores the mapping of string to a unique id. The id can be simplified as the implicit offset into the table.</span></p><br><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">Thus this representation exploits redundancy in the source file path prefix where there are a large number of source files in a small number of deeply nested directories.</span></p><br><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">Symbolizing the raw PC addresses in post-processing using llvm-profdata requires the binary to also be provided as input. As an alternative, we will also experiment with incrementally generating the symbolized call stack section as part of the raw profile dump at the cost of increased profiling overhead.</span></p><br><br><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">Profile Data matching in IR</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">—--------------------------</span></p><br><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">When matching the profile data, we may have already early inlined the direct caller of the allocation into its caller(s). This means we need to take some additional steps to identify the matching MIBs. For example, consider the following partial call graph:</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap"><br><br></span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">   ┌────────────────────┐           ┌────────────────────┐</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap"> A │ Call B; debug loc1 │         C │ Call B; debug loc2 │</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">   └───────┬────────────┘           └───────────┬────────┘</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">           │                                    │</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">           │                                    │</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">           │    ┌─────────────────────────┐     │</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">           └────► Call malloc; debug loc3 ◄─────┘</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">              B └─────────────────────────┘</span></p><br><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">There will be 2 MIB entries, one for each context (A->B and C->B). As noted earlier, the MIB profile entries will be owned by the function calling the allocation function. Therefore, we will keep both MIB entries associated with function B in the profile.</span></p><br><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">If early inlining (i.e. before profile matching) inlines B into A but not into C it will look like the following when we try to match the profile:</span></p><br><br><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">                                          ┌────────────────────┐</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">    ┌────────────────────────┐          C │ Call B; debug loc2 │</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">  A │Call malloc; debug loc3 │            └───────────┬────────┘</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">    │           ; inlined at │                        │</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">    │           ; debug loc1 │         ┌──────────────┴───────────┐</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">    └────────────────────────┘       B │ Call malloc; debug loc3  │</span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">                                       └──────────────────────────┘</span></p><br><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">Because the MIB corresponding to the A->B context is associated with function B in the profile, we do not find it by looking at function A’s profile when we see function A’s malloc call during matching. To address this we need to keep a correspondence from debug locations to the associated profile information. The details of the design will be shared in a separate RFC in the future.</span></p><font size="1"><span class="gmail_default"></span></font><br><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">[1] <a href="https://lists.llvm.org/pipermail/llvm-dev/2020-June/142744.html" target="_blank">https://lists.llvm.org/pipermail/llvm-dev/2020-June/142744.html</a><span class="gmail_default"></span></span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">[2] <a href="https://git.io/JzdRa" target="_blank">https://git.io/JzdRa</a></span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">[3] <a href="https://git.io/JzdRR" target="_blank">https://git.io/JzdRR</a></span></p><p dir="ltr" style="font-size:x-small;line-height:1.38;margin-top:0pt;margin-bottom:0pt"><span style="color:rgb(0,0,0);background-color:transparent;font-variant-numeric:normal;font-variant-east-asian:normal;vertical-align:baseline;white-space:pre-wrap">[4] <a href="https://git.io/JzdRN" target="_blank">https://git.io/JzdRN</a></span></p><font size="1"><span class="gmail_default"></span></font></font><br></div>
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