4 files changed, 19 insertions, 2 deletions
diff --git a/llvm/lib/TableGen/Record.cpp b/llvm/lib/TableGen/Record.cpp
index f447b3b1b47..80c0973644b 100644
--- a/llvm/lib/TableGen/Record.cpp
+++ b/llvm/lib/TableGen/Record.cpp
@@ -722,6 +722,11 @@ Init *UnOpInit::Fold(Record *CurRec, MultiClass *CurMultiClass) const {
     }
     break;
 
+  case SIZE:
+    if (ListInit *LHSl = dyn_cast<ListInit>(LHS))
+      return IntInit::get(LHSl->size());
+    break;
+
   case EMPTY:
     if (ListInit *LHSl = dyn_cast<ListInit>(LHS))
       return IntInit::get(LHSl->empty());
@@ -746,6 +751,7 @@ std::string UnOpInit::getAsString() const {
   case CAST: Result = "!cast<" + getType()->getAsString() + ">"; break;
   case HEAD: Result = "!head"; break;
   case TAIL: Result = "!tail"; break;
+  case SIZE: Result = "!size"; break;
   case EMPTY: Result = "!empty"; break;
   }
   return Result + "(" + LHS->getAsString() + ")";
diff --git a/llvm/lib/TableGen/TGLexer.cpp b/llvm/lib/TableGen/TGLexer.cpp
index 5d6f7c23e0b..bc03055eb23 100644
--- a/llvm/lib/TableGen/TGLexer.cpp
+++ b/llvm/lib/TableGen/TGLexer.cpp
@@ -469,6 +469,7 @@ tgtok::TokKind TGLexer::LexExclaim() {
     .Case("if", tgtok::XIf)
     .Case("head", tgtok::XHead)
     .Case("tail", tgtok::XTail)
+    .Case("size", tgtok::XSize)
     .Case("con", tgtok::XConcat)
     .Case("add", tgtok::XADD)
     .Case("and", tgtok::XAND)
diff --git a/llvm/lib/TableGen/TGLexer.h b/llvm/lib/TableGen/TGLexer.h
index b5b58161878..342eb76fc0f 100644
--- a/llvm/lib/TableGen/TGLexer.h
+++ b/llvm/lib/TableGen/TGLexer.h
@@ -48,7 +48,7 @@ namespace tgtok {
 
     // !keywords.
     XConcat, XADD, XAND, XOR, XSRA, XSRL, XSHL, XListConcat, XStrConcat, XCast,
-    XSubst, XForEach, XHead, XTail, XEmpty, XIf, XEq,
+    XSubst, XForEach, XHead, XTail, XSize, XEmpty, XIf, XEq,
 
     // Integer value.
     IntVal,
diff --git a/llvm/lib/TableGen/TGParser.cpp b/llvm/lib/TableGen/TGParser.cpp
index 17c2c2ee613..72ab8d3838d 100644
--- a/llvm/lib/TableGen/TGParser.cpp
+++ b/llvm/lib/TableGen/TGParser.cpp
@@ -781,6 +781,7 @@ Init *TGParser::ParseOperation(Record *CurRec, RecTy *ItemType) {
     return nullptr;
   case tgtok::XHead:
   case tgtok::XTail:
+  case tgtok::XSize:
   case tgtok::XEmpty:
   case tgtok::XCast: {  // Value ::= !unop '(' Value ')'
     UnOpInit::UnaryOp Code;
@@ -808,6 +809,11 @@ Init *TGParser::ParseOperation(Record *CurRec, RecTy *ItemType) {
       Lex.Lex();  // eat the operation
       Code = UnOpInit::TAIL;
       break;
+    case tgtok::XSize:
+      Lex.Lex();
+      Code = UnOpInit::SIZE;
+      Type = IntRecTy::get();
+      break;
     case tgtok::XEmpty:
       Lex.Lex();  // eat the operation
       Code = UnOpInit::EMPTY;
@@ -842,12 +848,15 @@ Init *TGParser::ParseOperation(Record *CurRec, RecTy *ItemType) {
         }
       }
 
-      if (Code == UnOpInit::HEAD || Code == UnOpInit::TAIL) {
+      if (Code == UnOpInit::HEAD || Code == UnOpInit::TAIL ||
+          Code == UnOpInit::SIZE) {
         if (!LHSl && !LHSt) {
           TokError("expected list type argument in unary operator");
           return nullptr;
         }
+      }
 
+      if (Code == UnOpInit::HEAD || Code == UnOpInit::TAIL) {
         if (LHSl && LHSl->empty()) {
           TokError("empty list argument in unary operator");
           return nullptr;
@@ -1453,6 +1462,7 @@ Init *TGParser::ParseSimpleValue(Record *CurRec, RecTy *ItemType,
 
   case tgtok::XHead:
   case tgtok::XTail:
+  case tgtok::XSize:
   case tgtok::XEmpty:
   case tgtok::XCast:  // Value ::= !unop '(' Value ')'
   case tgtok::XConcat: