diff --git a/llvm/lib/Transforms/IPO/ForceFunctionAttrs.cpp b/llvm/lib/Transforms/IPO/ForceFunctionAttrs.cpp
--- a/llvm/lib/Transforms/IPO/ForceFunctionAttrs.cpp
+++ b/llvm/lib/Transforms/IPO/ForceFunctionAttrs.cpp
@@ -16,18 +16,24 @@
 
 #define DEBUG_TYPE "forceattrs"
 
-static cl::list<std::string>
-    ForceAttributes("force-attribute", cl::Hidden,
-                    cl::desc("Add an attribute to a function. This should be a "
-                             "pair of 'function-name:attribute-name', for "
-                             "example -force-attribute=foo:noinline. This "
-                             "option can be specified multiple times."));
+static cl::list<std::string> ForceAttributes(
+    "force-attribute", cl::Hidden,
+    cl::desc(
+        "Add an attribute to a function. This can be a "
+        "pair of 'function-name:attribute-name', to apply an attribute to a "
+        "specific function. For "
+        "example -force-attribute=foo:noinline. Specifying only an attribute "
+        "will apply the attribute to every function in the module. This "
+        "option can be specified multiple times."));
 
 static cl::list<std::string> ForceRemoveAttributes(
     "force-remove-attribute", cl::Hidden,
-    cl::desc("Remove an attribute from a function. This should be a "
-             "pair of 'function-name:attribute-name', for "
-             "example -force-remove-attribute=foo:noinline. This "
+    cl::desc("Remove an attribute from a function. This can be a "
+             "pair of 'function-name:attribute-name' to remove an attribute "
+             "from a specific function. For "
+             "example -force-remove-attribute=foo:noinline. Specifying only an "
+             "attribute will remove the attribute from all functions in the "
+             "module. This "
              "option can be specified multiple times."));
 
 /// If F has any forced attributes given on the command line, add them.
@@ -36,13 +42,18 @@
 /// takes precedence.
 static void forceAttributes(Function &F) {
   auto ParseFunctionAndAttr = [&](StringRef S) {
-    auto Kind = Attribute::None;
-    auto KV = StringRef(S).split(':');
-    if (KV.first != F.getName())
-      return Kind;
-    Kind = Attribute::getAttrKindFromName(KV.second);
+    StringRef AttributeText;
+    if (S.contains(':')) {
+      auto KV = StringRef(S).split(':');
+      if (KV.first != F.getName())
+        return Attribute::None;
+      AttributeText = KV.second;
+    } else {
+      AttributeText = S;
+    }
+    auto Kind = Attribute::getAttrKindFromName(AttributeText);
     if (Kind == Attribute::None || !Attribute::canUseAsFnAttr(Kind)) {
-      LLVM_DEBUG(dbgs() << "ForcedAttribute: " << KV.second
+      LLVM_DEBUG(dbgs() << "ForcedAttribute: " << AttributeText
                         << " unknown or not a function attribute!\n");
     }
     return Kind;
diff --git a/llvm/test/Transforms/ForcedFunctionAttrs/forced.ll b/llvm/test/Transforms/ForcedFunctionAttrs/forced.ll
--- a/llvm/test/Transforms/ForcedFunctionAttrs/forced.ll
+++ b/llvm/test/Transforms/ForcedFunctionAttrs/forced.ll
@@ -4,6 +4,8 @@
 ; RUN: opt < %s -S -passes=forceattrs -force-remove-attribute goo:noinline | FileCheck %s --check-prefix=REMOVE-NOINLINE
 ; RUN: opt < %s -S -passes=forceattrs -force-attribute goo:cold -force-remove-attribute goo:noinline | FileCheck %s --check-prefix=ADD-COLD-REMOVE-NOINLINE
 ; RUN: opt < %s -S -passes=forceattrs -force-attribute goo:noinline -force-remove-attribute goo:noinline | FileCheck %s --check-prefix=ADD-NOINLINE-REMOVE-NOINLINE
+; RUN: opt < %s -S -passes=forceattrs -force-attribute optsize | FileCheck %s --check-prefix=CHECK-ADD-ALL
+; RUN: opt < %s -S -passes=forceattrs -force-remove-attribute noinline | FileCheck %s --check-prefix=CHECK-REMOVE-ALL
 
 ; CHECK-CONTROL: define void @foo() {
 ; CHECK-FOO: define void @foo() #0 {
@@ -32,3 +34,18 @@
 ; CHECK-FOO: attributes #0 = { noinline }
 ; REMOVE-COLD: attributes #0 = { noinline }
 ; ADD-COLD-REMOVE-NOINLINE: attributes #0 = { cold }
+
+; When passing an attribute without specifying a function, the attribute
+; should be added to all functions in the module.
+; CHECK-ADD-ALL: define void @foo() #0 {
+; CHECK-ADD-ALL: define void @goo() #1 {
+; CHECK-ADD-ALL: attributes #0 = { optsize }
+; CHECK-ADD-ALL: attributes #1 = { noinline optsize }
+
+; When passing an attribute to be removed without specifying a function,
+; the attribute should be removed from all functions in the module that
+; have it.
+; CHECK-REMOVE-ALL: define void @foo() {
+; CHECK-REMOVE-ALL: define void @goo() {
+; CHECK-REMOVE-ALL-NOT: attributes #0
+