From a2da78852b25ef098c91e5923e8edf205c3bf0c7 Mon Sep 17 00:00:00 2001
From: Jakob Stoklund Olesen <stoklund@2pi.dk>
Date: Wed, 7 Mar 2012 16:39:35 +0000
Subject: [PATCH] Fix infinite loop in nested multiclasses.

Patch by Michael Liao!

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@152232 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/TableGen/Record.cpp       |  8 ++----
 test/TableGen/TwoLevelName.td | 46 +++++++++++++++++++++++++++++++++++
 2 files changed, 48 insertions(+), 6 deletions(-)
 create mode 100644 test/TableGen/TwoLevelName.td

diff --git a/lib/TableGen/Record.cpp b/lib/TableGen/Record.cpp
index 12d1b1a4c95..93eed24b8dc 100644
--- a/lib/TableGen/Record.cpp
+++ b/lib/TableGen/Record.cpp
@@ -1726,12 +1726,6 @@ void Record::setName(Init *NewName) {
   }  // Otherwise this isn't yet registered.
   Name = NewName;
   checkName();
-  // Since the Init for the name was changed, see if we can resolve
-  // any of it using members of the Record.
-  Init *ComputedName = Name->resolveReferences(*this, 0);
-  if (ComputedName != Name) {
-    setName(ComputedName);
-  }
   // DO NOT resolve record values to the name at this point because
   // there might be default values for arguments of this def.  Those
   // arguments might not have been resolved yet so we don't want to
@@ -1754,6 +1748,8 @@ void Record::setName(const std::string &Name) {
 /// references.
 void Record::resolveReferencesTo(const RecordVal *RV) {
   for (unsigned i = 0, e = Values.size(); i != e; ++i) {
+    if (RV == &Values[i]) // Skip resolve the same field as the given one
+      continue;
     if (Init *V = Values[i].getValue())
       Values[i].setValue(V->resolveReferences(*this, RV));
   }
diff --git a/test/TableGen/TwoLevelName.td b/test/TableGen/TwoLevelName.td
new file mode 100644
index 00000000000..9c502f47550
--- /dev/null
+++ b/test/TableGen/TwoLevelName.td
@@ -0,0 +1,46 @@
+// RUN: llvm-tblgen %s | FileCheck %s
+// XFAIL: vg_leak
+
+class Type<string name, int length, int width> {
+  string Name = name;
+  int Length = length;
+  int Width = width;
+}
+
+multiclass OT1<string ss, int l, int w> {
+  def _#NAME# : Type<ss, l, w>;
+}
+multiclass OT2<string ss, int w> {
+  defm  v1#NAME# : OT1<!strconcat( "v1", ss),  1, w>;
+  defm  v2#NAME# : OT1<!strconcat( "v2", ss),  2, w>;
+  defm  v3#NAME# : OT1<!strconcat( "v3", ss),  3, w>;
+  defm  v4#NAME# : OT1<!strconcat( "v4", ss),  4, w>;
+  defm  v8#NAME# : OT1<!strconcat( "v8", ss),  8, w>;
+  defm v16#NAME# : OT1<!strconcat("v16", ss), 16, w>;
+}
+
+defm i8 : OT2<"i8", 8>;
+
+// CHECK: _v16i8
+// CHECK: Length = 16
+// CHECK: Width = 8
+
+// CHECK: _v1i8
+// CHECK: Length = 1
+// CHECK: Width = 8
+
+// CHECK: _v2i8
+// CHECK: Length = 2
+// CHECK: Width = 8
+
+// CHECK: _v3i8
+// CHECK: Length = 3
+// CHECK: Width = 8
+
+// CHECK: _v4i8
+// CHECK: Length = 4
+// CHECK: Width = 8
+
+// CHECK: _v8i8
+// CHECK: Length = 8
+// CHECK: Width = 8