From 8871b402ec162c1967b4b287cae4d5696983ccf5 Mon Sep 17 00:00:00 2001
From: "Paul C. Anagnostopoulos" <paul@windfall.com>
Date: Sun, 24 Jan 2021 13:30:31 -0500
Subject: [PATCH] [TableGen] [DetailedRecords] Print record name that is null
 string as ""

Differential Revision: https://reviews.llvm.org/D95312

Add a test for the backend.
---
 lib/TableGen/DetailedRecordsBackend.cpp |  3 ++-
 test/TableGen/detailed-records.td       | 36 +++++++++++++++++++++++++
 2 files changed, 38 insertions(+), 1 deletion(-)
 create mode 100644 test/TableGen/detailed-records.td

diff --git a/lib/TableGen/DetailedRecordsBackend.cpp b/lib/TableGen/DetailedRecordsBackend.cpp
index 2c3c3358b34..482a0d71da8 100644
--- a/lib/TableGen/DetailedRecordsBackend.cpp
+++ b/lib/TableGen/DetailedRecordsBackend.cpp
@@ -104,7 +104,8 @@ void DetailedRecordsEmitter::printRecords(raw_ostream &OS) {
 
   for (const auto &RecPair : RecordList) {
     auto *const Rec = RecPair.second.get();
-    OS << formatv("\n{0}  |{1}|\n", Rec->getNameInitAsString(),
+    std::string Name = Rec->getNameInitAsString();
+    OS << formatv("\n{0}  |{1}|\n", Name.empty() ? "\"\"" : Name,
                   SrcMgr.getFormattedLocationNoOffset(Rec->getLoc().front()));
     printDefms(Rec, OS);
     printSuperclasses(Rec, OS);
diff --git a/test/TableGen/detailed-records.td b/test/TableGen/detailed-records.td
new file mode 100644
index 00000000000..15b5f268f2c
--- /dev/null
+++ b/test/TableGen/detailed-records.td
@@ -0,0 +1,36 @@
+// RUN: llvm-tblgen -print-detailed-records %s | FileCheck %s
+
+// This test file ensures that the DetailedRecords backend prints all
+// the global variables, classes, and records.
+
+// CHECK: ----- Global Variables
+// CHECK: Answer
+// CHECK: Greeting
+
+// CHECK: ----- Classes
+// CHECK: Class1
+// CHECK: Class2
+
+// CHECK: ----- Records
+// CHECK: ""
+// CHECK: Info
+// CHECK: Rec1
+// CHECK: anonymous_0
+
+defvar Greeting = "Hello there.";
+defvar Answer = 42;
+
+class Class1 {
+}
+
+class Class2 {
+}
+
+def : Class1;
+
+def "" : Class2;
+
+def Rec1;
+
+def Info : Class1;
+