Index: ELF/Config.h
===================================================================
--- ELF/Config.h
+++ ELF/Config.h
@@ -101,6 +101,7 @@
   std::vector<VersionDefinition> VersionDefinitions;
   std::vector<llvm::StringRef> AuxiliaryList;
   std::vector<llvm::StringRef> FilterList;
+  std::vector<llvm::StringRef> KeepUnique;
   std::vector<llvm::StringRef> SearchPaths;
   std::vector<llvm::StringRef> SymbolOrderingFile;
   std::vector<llvm::StringRef> Undefined;
Index: ELF/Driver.cpp
===================================================================
--- ELF/Driver.cpp
+++ ELF/Driver.cpp
@@ -707,6 +707,7 @@
   Config->IgnoreFunctionAddressEquality =
       Args.hasArg(OPT_ignore_function_address_equality);
   Config->Init = Args.getLastArgValue(OPT_init, "_init");
+  Config->KeepUnique = args::getStrings(Args, OPT_keep_unique);
   Config->LTOAAPipeline = Args.getLastArgValue(OPT_lto_aa_pipeline);
   Config->LTODebugPassManager = Args.hasArg(OPT_lto_debug_pass_manager);
   Config->LTONewPassManager = Args.hasArg(OPT_lto_new_pass_manager);
Index: ELF/ICF.cpp
===================================================================
--- ELF/ICF.cpp
+++ ELF/ICF.cpp
@@ -413,12 +413,31 @@
     message(S);
 }
 
+// Record sections that define symbols mentioned in --keep-unique <symbol>
+// these sections are inelligible for ICF.
+static llvm::DenseSet<InputSectionBase *> findKeepUniqueSections() {
+  llvm::DenseSet<InputSectionBase *> KeepUniqueSections;
+  for (llvm::StringRef Name : Config->KeepUnique) {
+    if (Symbol *Sym = Symtab->find(Name)) {
+      if (auto *DefSym = dyn_cast<Defined>(Sym))
+        if (auto *IS = dyn_cast<InputSectionBase>(DefSym->Section))
+          KeepUniqueSections.insert(IS);
+    } else
+      warn("Could not find symbol " + Name + " to keep unique");
+  }
+  return KeepUniqueSections;
+}
+
 // The main function of ICF.
 template <class ELFT> void ICF<ELFT>::run() {
+  llvm::DenseSet<InputSectionBase *> KeepUniqueSections =
+      findKeepUniqueSections();
+
   // Collect sections to merge.
   for (InputSectionBase *Sec : InputSections)
     if (auto *S = dyn_cast<InputSection>(Sec))
-      if (isEligible(S))
+      if (isEligible(S) &&
+          KeepUniqueSections.find(S) == KeepUniqueSections.end())
         Sections.push_back(S);
 
   // Initially, we use hash values to partition sections.
Index: ELF/Options.td
===================================================================
--- ELF/Options.td
+++ ELF/Options.td
@@ -192,6 +192,8 @@
 
 defm just_symbols: Eq<"just-symbols">, HelpText<"Just link symbols">;
 
+defm keep_unique: Eq<"keep-unique">, HelpText<"Do not fold this symbol during ICF">;
+
 defm library: Eq<"library">, HelpText<"Root name of library to use">,
   MetaVarName<"<libName>">;
 
Index: test/ELF/icf-keep-unique.s
===================================================================
--- /dev/null
+++ test/ELF/icf-keep-unique.s
@@ -0,0 +1,53 @@
+# REQUIRES: x86
+
+# RUN: llvm-mc -filetype=obj -triple=x86_64-unknown-linux %s -o %t
+# RUN: ld.lld %t -o %t2 --icf=all --print-icf-sections | FileCheck %s
+# RUN: ld.lld %t -o %t2 --keep-unique f2 --keep-unique f4 --keep-unique f5 --icf=all --print-icf-sections 2>&1 | FileCheck %s -check-prefix=CHECK-KEEP
+
+// Base case, expect only .text.f1 to be kept
+// CHECK: selected section /linaro/icf/build/tools/lld/test/ELF/Output/icf-keep-unique.s.tmp:(.text.f1)
+// CHECK-NEXT:   removing identical section /linaro/icf/build/tools/lld/test/ELF/Output/icf-keep-unique.s.tmp:(.text.f2)
+// CHECK-NEXT:   removing identical section /linaro/icf/build/tools/lld/test/ELF/Output/icf-keep-unique.s.tmp:(.text.f3)
+// CHECK-NEXT:   removing identical section /linaro/icf/build/tools/lld/test/ELF/Output/icf-keep-unique.s.tmp:(.text.f4)
+// CHECK-NEXT:   removing identical section /linaro/icf/build/tools/lld/test/ELF/Output/icf-keep-unique.s.tmp:(.text.f5)
+
+// With --keep-unique f2, f4 and f5 we expect only f3 and f5 to be removed.
+// f5 is not matched by --keep-unique as it is a local symbol.
+// CHECK-KEEP: warning: Could not find symbol f5 to keep unique
+// CHECK-KEEP: selected section /linaro/icf/build/tools/lld/test/ELF/Output/icf-keep-unique.s.tmp:(.text.f1)
+// CHECK-KEEP-NEXT:   removing identical section /linaro/icf/build/tools/lld/test/ELF/Output/icf-keep-unique.s.tmp:(.text.f3)
+// CHECK-KEEP-NEXT:   removing identical section /linaro/icf/build/tools/lld/test/ELF/Output/icf-keep-unique.s.tmp:(.text.f5)
+ .globl _start, f1, f2, f3, f4
+_start:
+ ret
+
+ .section .text.f1, "ax"
+f1:
+  mov $60, %rax
+  mov $42, %rdi
+  syscall
+
+.section .text.f2, "ax"
+f2:
+  mov $60, %rax
+  mov $42, %rdi
+  syscall
+
+.section .text.f3, "ax"
+f3:
+  mov $60, %rax
+  mov $42, %rdi
+  syscall
+
+.section .text.f4, "ax"
+f4:
+  mov $60, %rax
+  mov $42, %rdi
+  syscall
+
+# f5 is local, not found by --keep-unique f5
+.section .text.f5, "ax"
+f5:
+  mov $60, %rax
+  mov $42, %rdi
+  syscall