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-rw-r--r--docs/Passes.rst19
1 files changed, 10 insertions, 9 deletions
diff --git a/docs/Passes.rst b/docs/Passes.rst
index b2703b7c03..b51829d3a3 100644
--- a/docs/Passes.rst
+++ b/docs/Passes.rst
@@ -540,6 +540,8 @@ instructions that are obviously dead.
A trivial dead store elimination that only considers basic-block local
redundant stores.
+.. _passes-functionattrs:
+
``-functionattrs``: Deduce function attributes
----------------------------------------------
@@ -648,7 +650,7 @@ program, and is used for a wide variety of program transformations.
------------------------------------------------
Combine instructions to form fewer, simple instructions. This pass does not
-modify the CFG This pass is where algebraic simplification happens.
+modify the CFG. This pass is where algebraic simplification happens.
This pass combines things like:
@@ -681,6 +683,13 @@ program:
shifts.
#. … etc.
+This pass can also simplify calls to specific well-known function calls (e.g.
+runtime library functions). For example, a call ``exit(3)`` that occurs within
+the ``main()`` function can be transformed into simply ``return 3``. Whether or
+not library calls are simplified is controlled by the
+:ref:`-functionattrs <passes-functionattrs>` pass and LLVM's knowledge of
+library calls on different targets.
+
``-internalize``: Internalize Global Symbols
--------------------------------------------
@@ -1011,14 +1020,6 @@ as:
Note that this pass has a habit of making definitions be dead. It is a good
idea to run a :ref:`DCE <passes-dce>` pass sometime after running this pass.
-``-simplify-libcalls``: Simplify well-known library calls
----------------------------------------------------------
-
-Applies a variety of small optimizations for calls to specific well-known
-function calls (e.g. runtime library functions). For example, a call
-``exit(3)`` that occurs within the ``main()`` function can be transformed into
-simply ``return 3``.
-
.. _passes-simplifycfg:
``-simplifycfg``: Simplify the CFG