diff --git a/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp b/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp
--- a/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp
+++ b/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp
@@ -3883,7 +3883,8 @@
     Flags |= 0x10;
   Stream.EmitRecord(bitc::FS_FLAGS, ArrayRef<uint64_t>{Flags});
 
-  for (const auto &GVI : valueIds()) {
+  const std::map<GlobalValue::GUID, unsigned> &ValueIds = valueIds();
+  for (const auto &GVI : ValueIds) {
     Stream.EmitRecord(bitc::FS_VALUE_GUID,
                       ArrayRef<uint64_t>{GVI.second, GVI.first});
   }
@@ -3962,9 +3963,13 @@
     NameVals.clear();
   };
 
+  std::set<GlobalValue::GUID> DefOrUseGUIDs;
   forEachSummary([&](GVInfo I, bool IsAliasee) {
     GlobalValueSummary *S = I.second;
     assert(S);
+    DefOrUseGUIDs.insert(I.first);
+    for (const ValueInfo &VI : S->refs())
+      DefOrUseGUIDs.insert(VI.getGUID());
 
     auto ValueId = getValueId(I.first);
     assert(ValueId);
@@ -4105,20 +4110,28 @@
 
   if (!Index.cfiFunctionDefs().empty()) {
     for (auto &S : Index.cfiFunctionDefs()) {
-      NameVals.push_back(StrtabBuilder.add(S));
-      NameVals.push_back(S.size());
+      if (DefOrUseGUIDs.count(GlobalValue::getGUID(GlobalValue::dropLLVMManglingEscape(S)))) {
+        NameVals.push_back(StrtabBuilder.add(S));
+        NameVals.push_back(S.size());
+      }
+    }
+    if (!NameVals.empty()) {
+      Stream.EmitRecord(bitc::FS_CFI_FUNCTION_DEFS, NameVals);
+      NameVals.clear();
     }
-    Stream.EmitRecord(bitc::FS_CFI_FUNCTION_DEFS, NameVals);
-    NameVals.clear();
   }
 
   if (!Index.cfiFunctionDecls().empty()) {
     for (auto &S : Index.cfiFunctionDecls()) {
-      NameVals.push_back(StrtabBuilder.add(S));
-      NameVals.push_back(S.size());
+      if (DefOrUseGUIDs.count(GlobalValue::getGUID(GlobalValue::dropLLVMManglingEscape(S)))) {
+        NameVals.push_back(StrtabBuilder.add(S));
+        NameVals.push_back(S.size());
+      }
+    }
+    if (!NameVals.empty()) {
+      Stream.EmitRecord(bitc::FS_CFI_FUNCTION_DECLS, NameVals);
+      NameVals.clear();
     }
-    Stream.EmitRecord(bitc::FS_CFI_FUNCTION_DECLS, NameVals);
-    NameVals.clear();
   }
 
   // Walk the GUIDs that were referenced, and write the
diff --git a/llvm/test/ThinLTO/X86/Inputs/cfi-icall-only-bazqux.ll b/llvm/test/ThinLTO/X86/Inputs/cfi-icall-only-bazqux.ll
new file mode 100644
--- /dev/null
+++ b/llvm/test/ThinLTO/X86/Inputs/cfi-icall-only-bazqux.ll
@@ -0,0 +1,24 @@
+target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
+target triple = "x86_64-unknown-linux-gnu"
+
+declare !type !0 i8 @bar(i8*)
+declare i1 @llvm.type.test(i8* %ptr, metadata %type) nounwind readnone
+
+define i8 @baz(i8* %p) !type !0 {
+  %x = call i1 @llvm.type.test(i8* %p, metadata !"t1")
+  %1 = select i1 %x, i8 0, i8 3
+  ret i8 %1
+}
+
+define i8 @qux(i8* %p) !type !0 {
+  %x = call i1 @llvm.type.test(i8* %p, metadata !"t1")
+  ret i8 4
+}
+
+define i8 @g(i1 %i, i8* %p) {
+  %1 = select i1 %i, i8(i8*)* @bar, i8(i8*)* @qux
+  %2 = call i8 %1(i8* %p)
+  ret i8 %2
+}
+
+!0 = !{i64 0, !"t1"}
diff --git a/llvm/test/ThinLTO/X86/cfi-icall-only-defuse.ll b/llvm/test/ThinLTO/X86/cfi-icall-only-defuse.ll
new file mode 100644
--- /dev/null
+++ b/llvm/test/ThinLTO/X86/cfi-icall-only-defuse.ll
@@ -0,0 +1,56 @@
+; Verifies that only functions defined or used by each module make it into the
+; CFI functions sets in that module's distributed index.
+; RUN: opt -thinlto-bc -thinlto-split-lto-unit %s -o %t1.bc
+; RUN: opt -thinlto-bc -thinlto-split-lto-unit %S/Inputs/cfi-icall-only-bazqux.ll -o %t2.bc
+; RUN: llvm-lto2 run  -thinlto-distributed-indexes %t1.bc %t2.bc -o %t.out \
+; RUN:   -r %t1.bc,bar,plx \
+; RUN:   -r %t1.bc,baz,x   \
+; RUN:   -r %t1.bc,f,plx   \
+; RUN:   -r %t1.bc,foo,plx \
+; RUN:   -r %t2.bc,bar,x   \
+; RUN:   -r %t2.bc,baz,plx \
+; RUN:   -r %t2.bc,g,plx   \
+; RUN:   -r %t2.bc,qux,plx
+; RUN: llvm-bcanalyzer -dump %t1.bc.thinlto.bc | FileCheck %s --check-prefix=FOOBAZ
+; RUN: llvm-bcanalyzer -dump %t2.bc.thinlto.bc | FileCheck %s --check-prefix=BARQUX
+
+target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
+target triple = "x86_64-unknown-linux-gnu"
+
+declare !type !0 i8 @baz(i8*)
+declare i1 @llvm.type.test(i8* %ptr, metadata %type) nounwind readnone
+
+define i8 @foo(i8* %p) !type !0 {
+  %x = call i1 @llvm.type.test(i8* %p, metadata !"t1")
+  %1 = select i1 %x, i8 0, i8 1
+  ret i8 %1
+}
+
+define i8 @bar(i8* %p) !type !0 {
+  %x = call i1 @llvm.type.test(i8* %p, metadata !"t1")
+  ret i8 2
+}
+
+define i8 @f(i1 %i, i8* %p) {
+  %1 = select i1 %i, i8(i8*)* @foo, i8(i8*)* @baz
+  %2 = call i8 %1(i8* %p)
+  ret i8 %2
+}
+
+!0 = !{i64 0, !"t1"}
+
+; FOOBAZ:   <GLOBALVAL_SUMMARY_BLOCK
+; FOOBAZ:     <CFI_FUNCTION_DEFS op0=0 op1=3 op2=3 op3=3 op4=6 op5=3/>
+; FOOBAZ:     <TYPE_ID op0=9 op1=2 op2=4 op3=7 op4=0 op5=0 op6=0 op7=0/>
+; FOOBAZ:   </GLOBALVAL_SUMMARY_BLOCK>
+; FOOBAZ:      <STRTAB_BLOCK
+; FOOBAZ-NEXT:   <BLOB abbrevid=4/> blob data = 'barbazfoot1'
+; FOOBAZ-NEXT: </STRTAB_BLOCK>
+
+; BARQUX:   <GLOBALVAL_SUMMARY_BLOCK
+; BARQUX:     <CFI_FUNCTION_DEFS op0=0 op1=3 op2=3 op3=3 op4=6 op5=3/>
+; BARQUX:     <TYPE_ID op0=9 op1=2 op2=4 op3=7 op4=0 op5=0 op6=0 op7=0/>
+; BARQUX:   </GLOBALVAL_SUMMARY_BLOCK>
+; BARQUX:      <STRTAB_BLOCK
+; BARQUX-NEXT:   <BLOB abbrevid=4/> blob data = 'barbazquxt1'
+; BARQUX-NEXT: </STRTAB_BLOCK>