Index: llvm/include/llvm/Transforms/Utils/FunctionComparator.h
===================================================================
--- llvm/include/llvm/Transforms/Utils/FunctionComparator.h
+++ llvm/include/llvm/Transforms/Utils/FunctionComparator.h
@@ -329,6 +329,8 @@
 
 private:
   int cmpOrderings(AtomicOrdering L, AtomicOrdering R) const;
+  int cmpMetadataAsValue(const MetadataAsValue *L,
+                         const MetadataAsValue *R) const;
   int cmpInlineAsm(const InlineAsm *L, const InlineAsm *R) const;
   int cmpAttrs(const AttributeList L, const AttributeList R) const;
   int cmpRangeMetadata(const MDNode *L, const MDNode *R) const;
Index: llvm/lib/Transforms/Utils/FunctionComparator.cpp
===================================================================
--- llvm/lib/Transforms/Utils/FunctionComparator.cpp
+++ llvm/lib/Transforms/Utils/FunctionComparator.cpp
@@ -720,6 +720,16 @@
   return 0;
 }
 
+int FunctionComparator::cmpMetadataAsValue(const MetadataAsValue *L,
+                                           const MetadataAsValue *R) const {
+  if (L == R)
+    return 0;
+
+  // Identical metadata is automatically merged, so let's just compare pointer
+  // identity.
+  return L < R ? -1 : 1;
+}
+
 int FunctionComparator::cmpInlineAsm(const InlineAsm *L,
                                      const InlineAsm *R) const {
   // InlineAsm's are uniqued. If they are the same pointer, obviously they are
@@ -772,6 +782,19 @@
   if (ConstR)
     return -1;
 
+  const MetadataAsValue *MDL = dyn_cast<MetadataAsValue>(L);
+  const MetadataAsValue *MDR = dyn_cast<MetadataAsValue>(R);
+  if (MDL && MDR) {
+    if (L == R)
+      return 0;
+    return cmpMetadataAsValue(MDL, MDR);
+  }
+
+  if (MDL)
+    return 1;
+  if (MDR)
+    return -1;
+
   const InlineAsm *InlineAsmL = dyn_cast<InlineAsm>(L);
   const InlineAsm *InlineAsmR = dyn_cast<InlineAsm>(R);
 
@@ -791,8 +814,10 @@
 // Test whether two basic blocks have equivalent behaviour.
 int FunctionComparator::cmpBasicBlocks(const BasicBlock *BBL,
                                        const BasicBlock *BBR) const {
-  BasicBlock::const_iterator InstL = BBL->begin(), InstLE = BBL->end();
-  BasicBlock::const_iterator InstR = BBR->begin(), InstRE = BBR->end();
+  auto WithoutDebugL = BBL->instructionsWithoutDebug();
+  auto WithoutDebugR = BBR->instructionsWithoutDebug();
+  auto InstL = WithoutDebugL.begin(), InstLE = WithoutDebugL.end();
+  auto InstR = WithoutDebugR.begin(), InstRE = WithoutDebugR.end();
 
   do {
     bool needToCmpOperands = true;
@@ -962,7 +987,7 @@
     // This random value acts as a block header, as otherwise the partition of
     // opcodes into BBs wouldn't affect the hash, only the order of the opcodes
     H.add(45798);
-    for (auto &Inst : *BB) {
+    for (auto &Inst : BB->instructionsWithoutDebug()) {
       H.add(Inst.getOpcode());
     }
     const Instruction *Term = BB->getTerminator();
Index: llvm/test/Transforms/MergeFunc/merge-type-metadata.ll
===================================================================
--- /dev/null
+++ llvm/test/Transforms/MergeFunc/merge-type-metadata.ll
@@ -0,0 +1,31 @@
+; RUN: opt -S -mergefunc < %s | FileCheck %s
+
+; CHECK: @call_vfunc1
+define internal i32 @call_vfunc1(i8* %vtable) unnamed_addr {
+  %a = tail call { i8*, i1 } @llvm.type.checked.load(i8* %vtable, i32 0, metadata !"vtype1")
+  ret i32 0
+}
+
+; CHECK-NOT: @call_vfunc2
+define internal i32 @call_vfunc2(i8* %vtable) unnamed_addr {
+  %a = tail call { i8*, i1 } @llvm.type.checked.load(i8* %vtable, i32 0, metadata !"vtype1")
+  ret i32 0
+}
+
+; CHECK: @call_vfunc3
+define internal i32 @call_vfunc3(i8* %vtable) unnamed_addr {
+  %a = tail call { i8*, i1 } @llvm.type.checked.load(i8* %vtable, i32 0, metadata !"vtype2")
+  ret i32 0
+}
+
+declare { i8*, i1 } @llvm.type.checked.load(i8*, i32, metadata)
+
+define void @main() {
+  %a = call i32 @call_vfunc1(i8* null)
+  ; CHECK: call i32 @call_vfunc1
+  %b = call i32 @call_vfunc2(i8* null)
+  ; CHECK: call i32 @call_vfunc1
+  %c = call i32 @call_vfunc3(i8* null)
+  ; CHECK: call i32 @call_vfunc3
+  ret void
+}