Fix some regular expressions in llvm-mode.el

[tromey]

Summary

llvm-mode.el had a few incorrect regular expressions.

In some cases it was using "\" unnecessarily. In another case it
needed an additional "\" to properly indicate a numbered sub-match.

Make comment-start buffer-local in llvm-mode.el

llvm-mode was setting comment-start globally. However, it is better
to only set it locally in the current buffer.

Don't use purecopy in llvm-mode.el

There's no reason to use purecopy in llvm-mode.el.
purecopy is only needed for files that are dumped in emacs.

Add a version header to llvm-mode.el

Adding a version header to llvm-mode.el allows it to be installed by
the Emacs package manager. There are not many requirements on the
version number; however it is useful to users to bump it when
something significant changes. Here I've chosen just to start at 1.0.

[tromey]

Adding you for review because I think you reviewed earlier changes to this file.

I thought I was submitting a patch series but it seems that it was all squashed.
I could rewrite the commit message if you'd like.

[smeenai]

(adding Rafael's current Phabricator account)

[davide]

LGTM with a redacted commit message. Do you have commit access or you need me to commit it on your behalf?

[tromey]

Updated the commit message.

[tromey]

In D42084#989131, @davide wrote:

LGTM with a redacted commit message. Do you have commit access or you need me to commit it on your behalf?

I do not have commit access.

[• espindola]

r323705.
Thanks!

utils/emacs/llvm-mode.el

 ;;; llvm-mode.el --- Major mode for the LLVM assembler language.
 
 ;; Maintainer:  The LLVM team, http://llvm.org/
+;; Version: 1.0
 
 ;;; Commentary:
 
 ;; Major mode for editing LLVM IR files.
 
 ;;; Code:
 
 (defvar llvm-mode-syntax-table
   (let ((table (make-syntax-table)))
     (modify-syntax-entry ?% "_" table)
     (modify-syntax-entry ?. "_" table)
     (modify-syntax-entry ?\; "< " table)
     (modify-syntax-entry ?\n "> " table)
     table)
   "Syntax table used while in LLVM mode.")
 
 (defvar llvm-font-lock-keywords
   (list
    ;; Variables
-   '("%[-a-zA-Z$\._][-a-zA-Z$\._0-9]*" . font-lock-variable-name-face)
+   '("%[-a-zA-Z$._][-a-zA-Z$._0-9]*" . font-lock-variable-name-face)
    ;; Labels
-   '("[-a-zA-Z$\._0-9]+:" . font-lock-variable-name-face)
+   '("[-a-zA-Z$._0-9]+:" . font-lock-variable-name-face)
    ;; Unnamed variable slots
    '("%[-]?[0-9]+" . font-lock-variable-name-face)
    ;; Types
    `(,(regexp-opt '("void" "i1" "i8" "i16" "i32" "i64" "i128" "float" "double" "type" "label" "opaque") 'symbols) . font-lock-type-face)
    ;; Integer literals
    '("\\b[-]?[0-9]+\\b" . font-lock-preprocessor-face)
    ;; Floating point constants
-   '("\\b[-+]?[0-9]+\.[0-9]*\([eE][-+]?[0-9]+\)?\\b" . font-lock-preprocessor-face)
+   '("\\b[-+]?[0-9]+.[0-9]*\\([eE][-+]?[0-9]+\\)?\\b" . font-lock-preprocessor-face)
    ;; Hex constants
    '("\\b0x[0-9A-Fa-f]+\\b" . font-lock-preprocessor-face)
    ;; Keywords
    `(,(regexp-opt '("begin" "end" "true" "false" "zeroinitializer" "declare"
                     "define" "global" "constant" "const" "internal" "linkonce" "linkonce_odr"
                     "weak" "weak_odr" "appending" "uninitialized" "implementation" "..."
                     "null" "undef" "to" "except" "not" "target" "endian" "little" "big"
                     "pointersize" "volatile" "fastcc" "coldcc" "cc" "personality") 'symbols) . font-lock-keyword-face)
(if (fboundp 'prog-mode)
     'fundamental-mode))
 
 ;;;###autoload
 (define-derived-mode llvm-mode llvm-mode-prog-mode "LLVM"
   "Major mode for editing LLVM source files.
 \\{llvm-mode-map}
   Runs `llvm-mode-hook' on startup."
   (setq font-lock-defaults `(llvm-font-lock-keywords))
-  (setq comment-start ";"))
+  (setq-local comment-start ";"))
 
 ;; Associate .ll files with llvm-mode
 ;;;###autoload
-(add-to-list 'auto-mode-alist (cons (purecopy "\\.ll\\'")  'llvm-mode))
+(add-to-list 'auto-mode-alist (cons "\\.ll\\'" 'llvm-mode))
 
 (provide 'llvm-mode)
 
 ;;; llvm-mode.el ends here