Allow multiclass def names to contain "#NAME"" where TableGen replaces
#NAME# with the name of the defm instantiating the multiclass.  This is
useful for AVX instruction naming where a "V" prefix is standard
throughout the ISA.  For example:

multiclass SSE_AVX_Inst<...> {
   def SS : Instr<...>;
   def SD : Instr<...>;
   def PS : Instr<...>;
   def PD : Instr<...>;

   def V#NAME#SS : Instr<...>;
   def V#NAME#SD : Instr<...>;
   def V#NAME#PS : Instr<...>;
   def V#NAME#PD : Instr<...>;
}

defm ADD : SSE_AVX_Inst<...>;

Results in 

ADDSS
ADDSD
ADDPS
ADDPD

VADDSS
VADDSD
VADDPS
VADDPD


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@70979 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/utils/TableGen/TGLexer.cpp b/utils/TableGen/TGLexer.cpp
index f2ea7a1..8eb219b 100644
--- a/utils/TableGen/TGLexer.cpp
+++ b/utils/TableGen/TGLexer.cpp
@@ -98,7 +98,7 @@
   switch (CurChar) {
   default:
     // Handle letters: [a-zA-Z_]
-    if (isalpha(CurChar) || CurChar == '_')
+    if (isalpha(CurChar) || CurChar == '_' || CurChar == '#')
       return LexIdentifier();
       
     // Unknown character, emit an error.
@@ -220,8 +220,20 @@
   const char *IdentStart = TokStart;
   
   // Match the rest of the identifier regex: [0-9a-zA-Z_]*
-  while (isalpha(*CurPtr) || isdigit(*CurPtr) || *CurPtr == '_')
-    ++CurPtr;
+  while (isalpha(*CurPtr) || isdigit(*CurPtr) || *CurPtr == '_'
+         || *CurPtr == '#') {
+    // If this contains a '#', make sure it's value
+    if (*CurPtr == '#') {
+      if (strncmp(CurPtr, "#NAME#", 6) != 0) {
+        return tgtok::Error;
+      }
+      CurPtr += 6;
+    }
+    else {
+      ++CurPtr;
+    }
+  }
+  
   
   // Check to see if this identifier is a keyword.
   unsigned Len = CurPtr-IdentStart;