Adding upstream version 86.0.1.upstream/86.0.1upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 28 insertions, 0 deletions

diff --git a/build/docs/pgo.rst b/build/docs/pgo.rst
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+.. _pgo:
+
+===========================
+Profile Guided Optimization
+===========================
+
+:abbr:`PGO (Profile Guided Optimization)` is the process of adding
+probes to a compiled binary, running said binary, then using the
+run-time information to *recompile* the binary to (hopefully) make it
+faster.
+
+How PGO Builds Work
+===================
+
+The supported interface for invoking a PGO build is to add ``MOZ_PGO=1`` to
+configure flags and then build. e.g. in your mozconfig::
+
+    ac_add_options MOZ_PGO=1
+
+Then::
+
+    $ ./mach build
+
+This is roughly equivalent to::
+
+#. Perform a build with *--enable-profile-generate* in $topobjdir/instrumented
+#. Perform a run of the instrumented binaries with build/pgo/profileserver.py
+#. Perform a build with *--enable-profile-use* in $topobjdir