[FileCheck] Implement -v and -vv for tracing matches
-v prints all directive pattern matches.
-vv additionally prints info that might be noise to users but that can
be helpful to FileCheck developers.
To maximize code reuse and to make diagnostics more consistent, this
patch also adjusts and extends some of the existing diagnostics.
CHECK-NOT failures now report variables uses. Many more diagnostics
now report the check prefix and kind of directive.
Reviewed By: probinson
Differential Revision: https://reviews.llvm.org/D47114
llvm-svn: 336967
diff --git a/llvm/docs/CommandGuide/FileCheck.rst b/llvm/docs/CommandGuide/FileCheck.rst
index ac7e810..dfa2fd2 100644
--- a/llvm/docs/CommandGuide/FileCheck.rst
+++ b/llvm/docs/CommandGuide/FileCheck.rst
@@ -95,6 +95,16 @@
Show the version number of this program.
+.. option:: -v
+
+ Print directive pattern matches.
+
+.. option:: -vv
+
+ Print information helpful in diagnosing internal FileCheck issues, such as
+ discarded overlapping ``CHECK-DAG:`` matches, implicit EOF pattern matches,
+ and ``CHECK-NOT:`` patterns that do not have matches. Implies ``-v``.
+
.. option:: --allow-deprecated-dag-overlap
Enable overlapping among matches in a group of consecutive ``CHECK-DAG:``