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| author | Sjoerd Meijer <sjoerd.meijer@arm.com> | 2017-10-13 14:02:36 +0000 |
|---|---|---|
| committer | Sjoerd Meijer <sjoerd.meijer@arm.com> | 2017-10-13 14:02:36 +0000 |
| commit | a0af046f39828a5797011f70c31bd36d8a2b19bb (patch) | |
| tree | 9ee43d1cb4db708d3f51a7f08551518da261448e /docs/CommandGuide | |
| parent | 44847b2e9838888e1536c90ad442a3958362139a (diff) | |
[FileCheck] regexp doc update/fix
Minor doc update that the FileCheck matcher supports POSIX ERE.
It also fixes a minor issue in the regexp describing a variable
name: underscores are allowed too.
Differential Revision: https://reviews.llvm.org/D38787
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@315679 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'docs/CommandGuide')
| -rw-r--r-- | docs/CommandGuide/FileCheck.rst | 11 |
1 files changed, 6 insertions, 5 deletions
diff --git a/docs/CommandGuide/FileCheck.rst b/docs/CommandGuide/FileCheck.rst index 8830c394b212..44cc57cebafe 100644 --- a/docs/CommandGuide/FileCheck.rst +++ b/docs/CommandGuide/FileCheck.rst @@ -397,10 +397,11 @@ All FileCheck directives take a pattern to match. For most uses of FileCheck, fixed string matching is perfectly sufficient. For some things, a more flexible form of matching is desired. To support this, FileCheck allows you to specify regular expressions in matching strings, -surrounded by double braces: ``{{yourregex}}``. Because we want to use fixed -string matching for a majority of what we do, FileCheck has been designed to -support mixing and matching fixed string matching with regular expressions. -This allows you to write things like this: +surrounded by double braces: ``{{yourregex}}``. FileCheck implements a POSIX +regular expression matcher; it supports Extended POSIX regular expressions +(ERE). Because we want to use fixed string matching for a majority of what we +do, FileCheck has been designed to support mixing and matching fixed string +matching with regular expressions. This allows you to write things like this: .. code-block:: llvm @@ -434,7 +435,7 @@ The first check line matches a regex ``%[a-z]+`` and captures it into the variable ``REGISTER``. The second line verifies that whatever is in ``REGISTER`` occurs later in the file after an "``andw``". :program:`FileCheck` variable references are always contained in ``[[ ]]`` pairs, and their names can -be formed with the regex ``[a-zA-Z][a-zA-Z0-9]*``. If a colon follows the name, +be formed with the regex ``[a-zA-Z_][a-zA-Z0-9_]*``. If a colon follows the name, then it is a definition of the variable; otherwise, it is a use. :program:`FileCheck` variables can be defined multiple times, and uses always |