Revert "[FileCheck] Support comment directives"

This reverts commit 9a9a5f9893c8db05cebc8818eb8485bff61f7c74 to try to
fix a bot:

http://lab.llvm.org:8011/builders/llvm-clang-x86_64-expensive-checks-win/builds/23489

1 files changed, 3 insertions, 70 deletions

diff --git a/llvm/docs/CommandGuide/FileCheck.rst b/llvm/docs/CommandGuide/FileCheck.rst
index 7d9a69e..55fc3f0 100644
--- a/llvm/docs/CommandGuide/FileCheck.rst
+++ b/llvm/docs/CommandGuide/FileCheck.rst
@@ -39,31 +39,15 @@ and from the command line.
  match.  By default, these patterns are prefixed with "``CHECK:``".
  If you'd like to use a different prefix (e.g. because the same input
  file is checking multiple different tool or options), the
- :option:`--check-prefix` argument allows you to specify (without the trailing
- "``:``") one or more prefixes to match. Multiple prefixes are useful for tests
- which might change for different run options, but most lines remain the same.
-
- FileCheck does not permit duplicate prefixes, even if one is a check prefix
- and one is a comment prefix (see :option:`--comment-prefixes` below).
+ :option:`--check-prefix` argument allows you to specify one or more
+ prefixes to match. Multiple prefixes are useful for tests which might
+ change for different run options, but most lines remain the same.
 
 .. option:: --check-prefixes prefix1,prefix2,...
 
  An alias of :option:`--check-prefix` that allows multiple prefixes to be
  specified as a comma separated list.
 
-.. option:: --comment-prefixes prefix1,prefix2,...
-
- By default, FileCheck ignores any occurrence in ``match-filename`` of any check
- prefix if it is preceded on the same line by "``COM:``" or "``RUN:``". See the
- section `The "COM:" directive`_ for usage details.
-
- These default comment prefixes can be overridden by
- :option:`--comment-prefixes` if they are not appropriate for your testing
- environment. However, doing so is not recommended in LLVM's LIT-based test
- suites, which should be easier to maintain if they all follow a consistent
- comment style. In that case, consider proposing a change to the default
- comment prefixes instead.
-
 .. option:: --input-file filename
 
   File to check (defaults to stdin).
@@ -252,57 +236,6 @@ circumstances, for example, testing different architectural variants with
 In this case, we're testing that we get the expected code generation with
 both 32-bit and 64-bit code generation.
 
-The "COM:" directive
-~~~~~~~~~~~~~~~~~~~~
-
-Sometimes you want to disable a FileCheck directive without removing it
-entirely, or you want to write comments that mention a directive by name. The
-"``COM:``" directive makes it easy to do this. For example, you might have:
-
-.. code-block:: llvm
-
-   ; X32: pinsrd_1:
-   ; X32:    pinsrd $1, 4(%esp), %xmm0
-
-   ; COM: FIXME: X64 isn't working correctly yet for this part of codegen, but
-   ; COM: X64 will have something similar to X32:
-   ; COM:
-   ; COM:   X64: pinsrd_1:
-   ; COM:   X64:    pinsrd $1, %edi, %xmm0
-
-Without "``COM:``", you would need to use some combination of rewording and
-directive syntax mangling to prevent FileCheck from recognizing the commented
-occurrences of "``X32:``" and "``X64:``" above as directives. Moreover,
-FileCheck diagnostics have been proposed that might complain about the above
-occurrences of "``X64``" that don't have the trailing "``:``" because they look
-like directive typos. Dodging all these problems can be tedious for a test
-author, and directive syntax mangling can make the purpose of test code unclear.
-"``COM:``" avoids all these problems.
-
-A few important usage notes:
-
-* "``COM:``" within another directive's pattern does *not* comment out the
-  remainder of the pattern. For example:
-
-  .. code-block:: llvm
-
-     ; X32: pinsrd $1, 4(%esp), %xmm0 COM: This is part of the X32 pattern!
-
-  If you need to temporarily comment out part of a directive's pattern, move it
-  to another line. The reason is that FileCheck parses "``COM:``" in the same
-  manner as any other directive: only the first directive on the line is
-  recognized as a directive.
-
-* For the sake of LIT, FileCheck treats "``RUN:``" just like "``COM:``". If this
-  is not suitable for your test environment, see :option:`--comment-prefixes`.
-
-* FileCheck does not recognize "``COM``", "``RUN``", or any user-defined comment
-  prefix as a comment directive if it's combined with one of the usual check
-  directive suffixes, such as "``-NEXT:``" or "``-NOT:``", discussed below.
-  FileCheck treats such a combination as plain text instead. If it needs to act
-  as a comment directive for your test environment, define it as such with
-  :option:`--comment-prefixes`.
-
 The "CHECK-NEXT:" directive
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~