Allow '_' in FileCheck variable names, it is nice to have at least one

separate character.
 - Chris, OK?

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@89626 91177308-0d34-0410-b5e6-96231b3b80d8

2 files changed, 4 insertions, 3 deletions

diff --git a/docs/CommandGuide/FileCheck.pod b/docs/CommandGuide/FileCheck.pod
index d3f640d64d..32516ad87b 100644
--- a/docs/CommandGuide/FileCheck.pod
+++ b/docs/CommandGuide/FileCheck.pod
@@ -224,7 +224,7 @@ The first check line matches a regex (<tt>%[a-z]+</tt>) and captures it into
 the variables "REGISTER".  The second line verifies that whatever is in REGISTER
 occurs later in the file after an "andw".  FileCheck variable references are
 always contained in <tt>[[ ]]</tt> pairs, are named, and their names can be
-formed with the regex "<tt>[a-zA-Z][a-zA-Z0-9]*</tt>".  If a colon follows the
+formed with the regex "<tt>[a-zA-Z_][a-zA-Z0-9_]*</tt>".  If a colon follows the
 name, then it is a definition of the variable, if not, it is a use.
 
 FileCheck variables can be defined multiple times, and uses always get the
diff --git a/utils/FileCheck/FileCheck.cpp b/utils/FileCheck/FileCheck.cpp
index b4d1f84859..2bd6197e13 100644
--- a/utils/FileCheck/FileCheck.cpp
+++ b/utils/FileCheck/FileCheck.cpp
@@ -140,7 +140,7 @@ bool Pattern::ParsePattern(StringRef PatternStr, SourceMgr &SM) {
     // Named RegEx matches.  These are of two forms: [[foo:.*]] which matches .*
     // (or some other regex) and assigns it to the FileCheck variable 'foo'. The
     // second form is [[foo]] which is a reference to foo.  The variable name
-    // itself must be of the form "[a-zA-Z][0-9a-zA-Z]*", otherwise we reject
+    // itself must be of the form "[a-zA-Z_][0-9a-zA-Z_]*", otherwise we reject
     // it.  This is to catch some common errors.
     if (PatternStr.size() >= 2 &&
         PatternStr[0] == '[' && PatternStr[1] == '[') {
@@ -167,7 +167,8 @@ bool Pattern::ParsePattern(StringRef PatternStr, SourceMgr &SM) {
 
       // Verify that the name is well formed.
       for (unsigned i = 0, e = Name.size(); i != e; ++i)
-        if ((Name[i] < 'a' || Name[i] > 'z') &&
+        if (Name[i] != '_' &&
+            (Name[i] < 'a' || Name[i] > 'z') &&
             (Name[i] < 'A' || Name[i] > 'Z') &&
             (Name[i] < '0' || Name[i] > '9')) {
           SM.PrintMessage(SMLoc::getFromPointer(Name.data()+i),