Rewrite docs/LeakSanitizer.rst. Add it to index.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@196957 91177308-0d34-0410-b5e6-96231b3b80d8

docs/LeakSanitizer.rst

@@ -8,16 +8,21 @@ LeakSanitizer
 Introduction
 ============
 
-LeakSanitizer is a heap leak detector which is designed to be used on top of
-:doc:`AddressSanitizer` / :doc:`MemorySanitizer`, or as a standalone library.
-LeakSanitizer is a run-time tool which doesn't require compiler
-instrumentation.
+LeakSanitizer is a run-time memory leak detector. It can be combined with
+:doc:`AddressSanitizer` to get both memory error and leak detection.
+LeakSanitizer does not introduce any additional slowdown when used in this mode.
+The LeakSanitizer runtime can also be linked in separately to get leak detection
+only, at a minimal performance cost.
 
 Current status
 ==============
 
-LeakSanitizer is a work in progress, currently under development for
-x86\_64 Linux.
+LeakSanitizer is experimental and supported only on x86\_64 Linux.
+
+The combined mode has been tested on fairly large software projects. The
+stand-alone mode has received much less testing.
+
+There are plans to support LeakSanitizer in :doc:`MemorySanitizer` builds.
 
 More Information
 ================

docs/index.rst

@@ -23,15 +23,11 @@ Using Clang as a Compiler
    ThreadSanitizer
    MemorySanitizer
    DataFlowSanitizer
+   LeakSanitizer
    SanitizerSpecialCaseList
    Modules
    FAQ
 
-.. toctree::
-   :hidden:
-
-   LeakSanitizer
-
 Using Clang as a Library
 ========================