diff --git a/llvm/test/tools/llvm-ar/count.test b/llvm/test/tools/llvm-ar/count.test
new file mode 100644
--- /dev/null
+++ b/llvm/test/tools/llvm-ar/count.test
@@ -0,0 +1,80 @@
+# Test the 'N' count parameter.
+
+# Get a temp clean cwd to extract into.
+RUN: rm -rf %t && mkdir -p %t && cd %t
+
+RUN: mkdir -p %t/x %t/y %t/z
+RUN: echo hello > %t/x/foo.txt
+RUN: echo cool  > %t/y/foo.txt
+RUN: echo world > %t/z/foo.txt
+RUN: echo fizz   > %t/x/bar.txt
+RUN: echo buzz   > %t/y/bar.txt
+RUN: echo fizbuz > %t/z/bar.txt
+RUN: llvm-ar rc %t/archive.a %t/x/foo.txt %t/y/foo.txt %t/z/foo.txt \
+RUN:     %t/x/bar.txt %t/y/bar.txt %t/z/bar.txt
+RUN: llvm-ar t %t/archive.a | FileCheck %s --check-prefix=LIST-MEMBERS
+
+# Make sure we set it up correctly.
+LIST-MEMBERS:      foo.txt
+LIST-MEMBERS-NEXT: foo.txt
+LIST-MEMBERS-NEXT: foo.txt
+LIST-MEMBERS-NEXT: bar.txt
+LIST-MEMBERS-NEXT: bar.txt
+LIST-MEMBERS-NEXT: bar.txt
+
+# Must be a number.
+RUN: not llvm-ar xN abc %t/archive.a foo.txt 2>&1 | FileCheck %s --check-prefix=ERR-NOT-NUM
+RUN: not llvm-ar xN 0x1 %t/archive.a foo.txt 2>&1 | FileCheck %s --check-prefix=ERR-NOT-NUM
+# Only three members named foo, so 1 <= N <= 3.
+RUN: not llvm-ar xN 0 %t/archive.a foo.txt 2>&1 | FileCheck %s --check-prefix=ERR-NOT-POS
+RUN: not llvm-ar xN 4 %t/archive.a foo.txt 2>&1 | FileCheck %s --check-prefix=ERR-NOT-FOUND
+# N only applies to x/d.
+RUN: not llvm-ar rN 1 %t/archive.a foo.txt 2>&1 | FileCheck %s --check-prefix=ERR-BAD-OP
+
+ERR-NOT-NUM:   error: Value for [count] must be numeric
+ERR-NOT-POS:   error: Value for [count] must be positive
+ERR-BAD-OP:    error: The 'N' modifier can only be specified with the 'x' or 'd' operations
+ERR-NOT-FOUND: error: 'foo.txt' was not found
+
+# Extract individual items.
+
+RUN: rm -f foo.txt bar.txt
+RUN: llvm-ar xN 1 %t/archive.a foo.txt bar.txt
+RUN: cat %t/foo.txt | FileCheck %s --check-prefix=FOO-1
+RUN: cat %t/bar.txt | FileCheck %s --check-prefix=BAR-1
+
+RUN: rm -f foo.txt bar.txt
+RUN: llvm-ar xN 2 %t/archive.a foo.txt bar.txt
+RUN: cat %t/foo.txt | FileCheck %s --check-prefix=FOO-2
+RUN: cat %t/bar.txt | FileCheck %s --check-prefix=BAR-2
+
+RUN: rm -f foo.txt bar.txt
+RUN: llvm-ar xN 3 %t/archive.a foo.txt bar.txt
+RUN: cat %t/foo.txt | FileCheck %s --check-prefix=FOO-3
+RUN: cat %t/bar.txt | FileCheck %s --check-prefix=BAR-3
+
+# Delete individual items.
+
+# Deleting the second member named foo means the new second member of the
+# archive is what used to be the third element.
+RUN: rm -f foo.txt bar.txt
+RUN: llvm-ar dN 2 %t/archive.a foo.txt
+RUN: llvm-ar xN 2 %t/archive.a foo.txt bar.txt
+RUN: cat %t/foo.txt | FileCheck %s --check-prefix=FOO-3
+RUN: cat %t/bar.txt | FileCheck %s --check-prefix=BAR-2
+
+# Deleting the first member from *both* archives means the new first member
+# named foo is the what used to be the third member, and the new first member
+# named bar is what used to be the second member.
+RUN: rm -f foo.txt bar.txt
+RUN: llvm-ar dN 1 %t/archive.a foo.txt bar.txt
+RUN: llvm-ar xN 1 %t/archive.a foo.txt bar.txt
+RUN: cat %t/foo.txt | FileCheck %s --check-prefix=FOO-3
+RUN: cat %t/bar.txt | FileCheck %s --check-prefix=BAR-2
+
+FOO-1: hello
+FOO-2: cool
+FOO-3: world
+BAR-1: fizz
+BAR-2: buzz
+BAR-3: fizbuz
diff --git a/llvm/tools/llvm-ar/llvm-ar.cpp b/llvm/tools/llvm-ar/llvm-ar.cpp
--- a/llvm/tools/llvm-ar/llvm-ar.cpp
+++ b/llvm/tools/llvm-ar/llvm-ar.cpp
@@ -66,7 +66,7 @@
 const char ArHelp[] = R"(
 OVERVIEW: LLVM Archiver
 
-USAGE: llvm-ar [options] [-]<operation>[modifiers] [relpos] <archive> [files]
+USAGE: llvm-ar [options] [-]<operation>[modifiers] [relpos] [count] <archive> [files]
        llvm-ar -M [<mri-script]
 
 OPTIONS:
@@ -97,6 +97,7 @@
   [i] - put [files] before [relpos] (same as [b])
   [l] - ignored for compatibility
   [L] - add archive's contents
+  [N] - use instance [count] of name
   [o] - preserve original dates
   [P] - use full names when matching (implied for thin archives)
   [s] - create an archive index (cf. ranlib)
@@ -187,6 +188,11 @@
 // one variable.
 static std::string RelPos;
 
+// Count parameter for 'N' modifier. This variable specifies which file should
+// match for extract/delete operations when there are multiple matches. This is
+// 1-indexed. A value of 0 is invalid, and implies 'N' is not used.
+static int CountParam = 0;
+
 // This variable holds the name of the archive file as given on the
 // command line.
 static std::string ArchiveName;
@@ -207,6 +213,19 @@
   PositionalArgs.erase(PositionalArgs.begin());
 }
 
+// Extract the parameter from the command line for the [count] argument
+// associated with the N modifier
+static void getCountParam() {
+  if (PositionalArgs.empty())
+    fail("Expected [count] for N modifier");
+  auto CountParamArg = StringRef(PositionalArgs[0]);
+  if (CountParamArg.getAsInteger(10, CountParam))
+    fail("Value for [count] must be numeric, got: " + CountParamArg);
+  if (CountParam < 1)
+    fail("Value for [count] must be positive, got: " + CountParamArg);
+  PositionalArgs.erase(PositionalArgs.begin());
+}
+
 // Get the archive file name from the command line
 static void getArchive() {
   if (PositionalArgs.empty())
@@ -336,6 +355,9 @@
     case 'U':
       Deterministic = false;
       break;
+    case 'N':
+      getCountParam();
+      break;
     case 'T':
       Thin = true;
       // Thin archives store path names, so P should be forced.
@@ -371,11 +393,14 @@
     fail("Only one operation may be specified");
   if (NumPositional > 1)
     fail("You may only specify one of a, b, and i modifiers");
-  if (AddAfter || AddBefore) {
+  if (AddAfter || AddBefore)
     if (Operation != Move && Operation != ReplaceOrInsert)
       fail("The 'a', 'b' and 'i' modifiers can only be specified with "
            "the 'm' or 'r' operations");
-  }
+  if (CountParam)
+    if (Operation != Extract && Operation != Delete)
+      fail("The 'N' modifier can only be specified with the 'x' or 'd' "
+           "operations");
   if (OriginalDates && Operation != Extract)
     fail("The 'o' modifier is only applicable to the 'x' operation");
   if (OnlyUpdate && Operation != ReplaceOrInsert)
@@ -513,6 +538,7 @@
     fail("extracting from a thin archive is not supported");
 
   bool Filter = !Members.empty();
+  StringMap<int> MemberCount;
   {
     Error Err = Error::success();
     for (auto &C : OldArchive->children(Err)) {
@@ -526,6 +552,8 @@
         });
         if (I == Members.end())
           continue;
+        if (CountParam && ++MemberCount[Name] != CountParam)
+          continue;
         Members.erase(I);
       }
 
@@ -627,10 +655,10 @@
 static InsertAction computeInsertAction(ArchiveOperation Operation,
                                         const object::Archive::Child &Member,
                                         StringRef Name,
-                                        std::vector<StringRef>::iterator &Pos) {
+                                        std::vector<StringRef>::iterator &Pos,
+                                        StringMap<int> &MemberCount) {
   if (Operation == QuickAppend || Members.empty())
     return IA_AddOldMember;
-
   auto MI = find_if(
       Members, [Name](StringRef Path) { return Name == normalizePath(Path); });
 
@@ -639,8 +667,11 @@
 
   Pos = MI;
 
-  if (Operation == Delete)
+  if (Operation == Delete) {
+    if (CountParam && ++MemberCount[Name] != CountParam)
+      return IA_AddOldMember;
     return IA_Delete;
+  }
 
   if (Operation == Move)
     return IA_MoveOldMember;
@@ -683,6 +714,7 @@
   StringRef PosName = normalizePath(RelPos);
   if (OldArchive) {
     Error Err = Error::success();
+    StringMap<int> MemberCount;
     for (auto &Child : OldArchive->children(Err)) {
       int Pos = Ret.size();
       Expected<StringRef> NameOrErr = Child.getName();
@@ -698,7 +730,7 @@
 
       std::vector<StringRef>::iterator MemberI = Members.end();
       InsertAction Action =
-          computeInsertAction(Operation, Child, Name, MemberI);
+          computeInsertAction(Operation, Child, Name, MemberI, MemberCount);
       switch (Action) {
       case IA_AddOldMember:
         addChildMember(Ret, Child, /*FlattenArchive=*/Thin);
@@ -715,7 +747,12 @@
         addMember(Moved, *MemberI);
         break;
       }
-      if (MemberI != Members.end())
+      // When processing elements with the count param, we need to preserve the
+      // full members list when iterating over all archive members. For
+      // instance, "llvm-ar dN 2 archive.a member.o" should delete the second
+      // file named member.o it sees; we are not done with member.o the first
+      // time we see it in the archive.
+      if (MemberI != Members.end() && !CountParam)
         Members.erase(MemberI);
     }
     failIfError(std::move(Err));