[TableGen] Allow references to class template arguments in defvar

We can't refer to template arguments for defvar statements in class
definitions, or it will report some errors like:

```
error: Variable not defined: 'xxx'.
```

The key point here is we used to pass nullptr to `ParseValue` in
`ParseDefvar`. As a result, we can't refer to template arguments
since `CurRec` is nullptr in `ParseIDValue`.

So we add an argument `CurRec` to `ParseDefvar` and provide it
when parsing defvar statements in class definitions.

Reviewed By: tra, simon_tatham

Differential Revision: https://reviews.llvm.org/D148197

1 files changed, 3 insertions, 3 deletions

diff --git a/llvm/lib/TableGen/TGParser.cpp b/llvm/lib/TableGen/TGParser.cpp
index 6c52edc..14c529c 100644
--- a/llvm/lib/TableGen/TGParser.cpp
+++ b/llvm/lib/TableGen/TGParser.cpp
@@ -3023,7 +3023,7 @@ bool TGParser::ParseBodyItem(Record *CurRec) {
     return ParseAssert(nullptr, CurRec);
 
   if (Lex.getCode() == tgtok::Defvar)
-    return ParseDefvar();
+    return ParseDefvar(CurRec);
 
   if (Lex.getCode() != tgtok::Let) {
     if (!ParseDeclaration(CurRec, false))
@@ -3254,7 +3254,7 @@ bool TGParser::ParseDefset() {
 ///
 ///   Defvar ::= DEFVAR Id '=' Value ';'
 ///
-bool TGParser::ParseDefvar() {
+bool TGParser::ParseDefvar(Record *CurRec) {
   assert(Lex.getCode() == tgtok::Defvar);
   Lex.Lex(); // Eat the 'defvar' token
 
@@ -3273,7 +3273,7 @@ bool TGParser::ParseDefvar() {
   if (!consume(tgtok::equal))
     return TokError("expected '='");
 
-  Init *Value = ParseValue(nullptr);
+  Init *Value = ParseValue(CurRec);
   if (!Value)
     return true;