diff --git a/llvm/lib/CodeGen/TargetLoweringObjectFileImpl.cpp b/llvm/lib/CodeGen/TargetLoweringObjectFileImpl.cpp
--- a/llvm/lib/CodeGen/TargetLoweringObjectFileImpl.cpp
+++ b/llvm/lib/CodeGen/TargetLoweringObjectFileImpl.cpp
@@ -611,15 +611,19 @@
     Name = getSectionPrefixForGlobal(Kind);
   }
 
+  bool HasPrefix = false;
   if (const auto *F = dyn_cast<Function>(GO)) {
-    if (Optional<StringRef> Prefix = F->getSectionPrefix())
+    if (Optional<StringRef> Prefix = F->getSectionPrefix()) {
       Name += *Prefix;
+      HasPrefix = true;
+    }
   }
 
   if (UniqueSectionName) {
     Name.push_back('.');
     TM.getNameWithPrefix(Name, GO, Mang, /*MayAlwaysUsePrivate*/true);
-  }
+  } else if (HasPrefix)
+    Name.push_back('.');
   return Name;
 }
 
diff --git a/llvm/test/Transforms/CodeGenPrepare/X86/section.ll b/llvm/test/Transforms/CodeGenPrepare/X86/section.ll
--- a/llvm/test/Transforms/CodeGenPrepare/X86/section.ll
+++ b/llvm/test/Transforms/CodeGenPrepare/X86/section.ll
@@ -1,10 +1,14 @@
 ; RUN: opt < %s -codegenprepare -S | FileCheck %s
+; RUN: llc < %s | FileCheck --check-prefix=ASM1 %s
+; RUN: llc < %s -function-sections | FileCheck --check-prefix=ASM2 %s
 
 target triple = "x86_64-pc-linux-gnu"
 
 ; This tests that hot/cold functions get correct section prefix assigned
 
 ; CHECK: hot_func1{{.*}}!section_prefix ![[HOT_ID:[0-9]+]]
+; ASM1: .section .text.hot.,"ax",@progbits
+; ASM2: .section .text.hot.hot_func1,"ax",@progbits
 ; The entry is hot
 define void @hot_func1() !prof !15 {
   ret void
@@ -40,6 +44,8 @@
 ; not call site VP metadata (which can exist on value profiled memcpy,
 ; or possibly left behind after static analysis based devirtualization).
 ; CHECK: cold_func1{{.*}}!section_prefix ![[COLD_ID:[0-9]+]]
+; ASM1: .section .text.unlikely.,"ax",@progbits
+; ASM2: .section .text.unlikely.cold_func1,"ax",@progbits
 define void @cold_func1() !prof !16 {
   call void @hot_func1(), !prof !17
   call void @hot_func1(), !prof !17