================
@@ -633,36 +631,36 @@ example:
// module M's interface, so is discarded
int c = use_h<int>(); // OK
-In the above example, the function definition of ``N::g`` is elided from the
Reduced
-BMI of ``M.cppm``. Then the use of ``use_g<int>`` in ``M-impl.cpp`` fails
-to instantiate. For such issues, users can add references to ``N::g`` in the
module purview
-of ``M.cppm`` to make sure it is reachable, e.g., ``using N::g;``.
-
-We think the Reduced BMI is the correct direction. But given it is a drastic
change,
-we'd like to make it experimental first to avoid breaking existing users. The
roadmap
-of Reduced BMI may be:
-
-1. ``-fexperimental-modules-reduced-bmi`` is opt in for 1~2 releases. The
period depends
-on testing feedbacks.
-2. We would announce Reduced BMI is not experimental and introduce
``-fmodules-reduced-bmi``.
-and suggest users to enable this mode. This may takes 1~2 releases too.
-3. Finally we will enable this by default. When that time comes, the term BMI
will refer to
-the reduced BMI today and the Full BMI will only be meaningful to build
systems which
-loves to support two phase compilations.
+In the above example, the function definition of ``N::g`` is elided from the
+Reduced BMI of ``M.cppm``. Then the use of ``use_g<int>`` in ``M-impl.cpp``
+fails to instantiate. For such issues, users can add references to ``N::g`` in
+the module purview of ``M.cppm`` to ensure it is reachable, e.g.,
+``using N::g;``.
+
+Long-term, Clang is likely to make Reduced BMIs the default rather than Full
+BMIs. But because it is a drastic change, it is initially an experimental
+option to avoid breaking existing users. The expected roadmap for Reduced BMIs
+as of Clang 19.x is:
+
+1. ``-fexperimental-modules-reduced-bmi`` is opt-in for 1~2 releases. The
period depends
+ on user feedback and may be extended.
+2. Announce that Reduced BMIs are no longer experimental and introduce
+ ``-fmodules-reduced-bmi`` as a new option, and recommend use of the new
+ option. This transition is expected to take 1~2 additional releases as well.
+3. Finally, ``-fmodules-reduced-bmi`` will be the default. When that time
+ comes, the term BMI will refer to the reduced BMI and the Full BMI will only
+ be meaningful to build systems which elect to support two-phase compilation.
Performance Tips
----------------
Reduce duplications
~~~~~~~~~~~~~~~~~~~
-While it is legal to have duplicated declarations in the global module
fragments
-of different module units, it is not free for clang to deal with the duplicated
-declarations. In other word, for a translation unit, it will compile slower if
the
-translation unit itself and its importing module units contains a lot
duplicated
-declarations.
-
-For example,
+While it is valid to have duplicated declarations in the global module
fragments
+of different module units, it is not free for Clang to deal with the duplicated
+declarations. A translation unit will compile more slowly if it and its
+imported module units contain a lot of duplicated declarations. For example:
----------------
Endilll wrote:
"A translation unit will compile more slowly if there is a lot of duplicated
declarations between the translation unit and modules it imports."
https://github.com/llvm/llvm-project/pull/90237
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