Document standard substitutions defined by lit.
Patch by Guilherme Bufolo!
Differential Revision: http://reviews.llvm.org/D18752
llvm-svn: 265314
diff --git a/llvm/docs/CommandGuide/lit.rst b/llvm/docs/CommandGuide/lit.rst
index 0ec14bb..b2da58e 100644
--- a/llvm/docs/CommandGuide/lit.rst
+++ b/llvm/docs/CommandGuide/lit.rst
@@ -355,6 +355,35 @@
configuration parameters --- for example, to change the test format, or the
suffixes which identify test files.
+PRE-DEFINED SUBSTITUTIONS
+~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+:program:`lit` provides various patterns that can be used with the RUN command.
+These are defined in TestRunner.py.
+
+ ========== ==============
+ Macro Substitution
+ ========== ==============
+ %s source path (path to the file currently being run)
+ %S source dir (directory of the file currently being run)
+ %p same as %S
+ %{pathsep} path separator
+ %t temporary file name unique to the test
+ %T temporary directory unique to the test
+ %% %
+ %/s same as %s but replace all / with \\
+ %/S same as %S but replace all / with \\
+ %/p same as %p but replace all / with \\
+ %/t same as %t but replace all / with \\
+ %/T same as %T but replace all / with \\
+ ========== ==============
+
+Further substitution patterns might be defined by each test module.
+See the modules :ref:`local-configuration-files`.
+
+More information on the testing infrastucture can be found in the
+:doc:`../TestingGuide`.
+
TEST RUN OUTPUT FORMAT
~~~~~~~~~~~~~~~~~~~~~~