Add clarifying note that sampling-based profiles cannot be used for code coverage.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@238031 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/docs/UsersManual.rst b/docs/UsersManual.rst
index 50d5d0192555c18535cbd43600289cf84811590f..2a6fc82a90debc612f76d48518e32ea65ea84f04 100644 (file)
--- a/docs/UsersManual.rst
+++ b/docs/UsersManual.rst
@@ -1290,6 +1290,10 @@ If you are not using Linux Perf to collect profiles, you will need to
 write a conversion tool from your profiler to LLVM's format. This section
 explains the file format expected by the backend.
 
+NOTE: This format is not intended to be used for code coverage. For that,
+you need to use Clang's instrumentation based profiling
+(``-fprofile-instr-generate``).
+
 Sample profiles are written as ASCII text. The file is divided into sections,
 which correspond to each of the functions executed at runtime. Each
 section has the following format (taken from