diff --git a/clang/lib/AST/Mangle.cpp b/clang/lib/AST/Mangle.cpp
--- a/clang/lib/AST/Mangle.cpp
+++ b/clang/lib/AST/Mangle.cpp
@@ -36,11 +36,10 @@
                                 StringRef Outer,
                                 const BlockDecl *BD,
                                 raw_ostream &Out) {
-  unsigned discriminator = Context.getBlockId(BD, true);
-  if (discriminator == 0)
-    Out << "__" << Outer << "_block_invoke";
-  else
-    Out << "__" << Outer << "_block_invoke_" << discriminator+1;
+  Out << "__" << Outer << "_block_invoke";
+  for (ParmVarDecl *PVD : BD->parameters()) {
+    Context.mangleTypeName(PVD->getType(), Out);
+  }
 }
 
 void MangleContext::anchor() { }
@@ -235,7 +234,6 @@
 void MangleContext::mangleGlobalBlock(const BlockDecl *BD,
                                       const NamedDecl *ID,
                                       raw_ostream &Out) {
-  unsigned discriminator = getBlockId(BD, false);
   if (ID) {
     if (shouldMangleDeclName(ID))
       mangleName(ID, Out);
@@ -243,10 +241,11 @@
       Out << ID->getIdentifier()->getName();
     }
   }
-  if (discriminator == 0)
-    Out << "_block_invoke";
-  else
-    Out << "_block_invoke_" << discriminator+1;
+
+  Out << "_block_invoke";
+  for (ParmVarDecl *PVD : BD->parameters()) {
+    mangleTypeName(PVD->getType(), Out);
+  }
 }
 
 void MangleContext::mangleCtorBlock(const CXXConstructorDecl *CD,
diff --git a/clang/test/CodeGen/block-with-perdefinedexpr.c b/clang/test/CodeGen/block-with-perdefinedexpr.c
--- a/clang/test/CodeGen/block-with-perdefinedexpr.c
+++ b/clang/test/CodeGen/block-with-perdefinedexpr.c
@@ -10,6 +10,6 @@
 {
  handler( ^(){ syslog("%s", __FUNCTION__); } );
 };
-// CHECK: @__FUNCTION__.spd_block_invoke_2 = private unnamed_addr constant [19 x i8] c"spd_block_invoke_2\00"
-// CHECK: define internal void @spd_block_invoke_2
-// CHECK: @__FUNCTION__.spd_block_invoke_2
+// CHECK: @__FUNCTION__.spd_block_invoke.1 = private unnamed_addr constant [19 x i8] c"spd_block_invoke.1\00"
+// CHECK: define internal void @spd_block_invoke
+// CHECK: @__FUNCTION__.spd_block_invoke
diff --git a/clang/test/CodeGen/block-with-perdefinedexpr.cpp b/clang/test/CodeGen/block-with-perdefinedexpr.cpp
--- a/clang/test/CodeGen/block-with-perdefinedexpr.cpp
+++ b/clang/test/CodeGen/block-with-perdefinedexpr.cpp
@@ -5,7 +5,7 @@
   const char * (^block1)() = ^() {
     return __FUNCTION__;
   };
-  // CHECK-DAG: @__FUNCTION__.___Z3barv_block_invoke_2 = private unnamed_addr constant [19 x i8] c"bar_block_invoke_2\00", align 1
+  // CHECK-DAG: @__FUNCTION__.___Z3barv_block_invoke.1 = private unnamed_addr constant [19 x i8] c"bar_block_invoke_2\00", align 1
   const char * (^block2)() = ^() {
     return __FUNCTION__;
   };
@@ -16,7 +16,7 @@
   const char * (^block1)() = ^() {
     return __PRETTY_FUNCTION__;
   };
-  // CHECK-DAG: @__PRETTY_FUNCTION__.___Z3bazv_block_invoke_2 = private unnamed_addr constant [26 x i8] c"void baz()_block_invoke_2\00", align 1
+  // CHECK-DAG: @__PRETTY_FUNCTION__.___Z3bazv_block_invoke.6 = private unnamed_addr constant [26 x i8] c"void baz()_block_invoke_2\00", align 1
   const char * (^block2)() = ^() {
     return __PRETTY_FUNCTION__;
   };
diff --git a/clang/test/CodeGen/blockwithlocalstatic.c b/clang/test/CodeGen/blockwithlocalstatic.c
--- a/clang/test/CodeGen/blockwithlocalstatic.c
+++ b/clang/test/CodeGen/blockwithlocalstatic.c
@@ -6,14 +6,18 @@
 	static int test=0;
 	return test;
 };
-// CHECK: @block1_block_invoke_2.test = internal global i32
+// CHECK: @block1_block_invoke.test = internal global i32
 void (^block1)(void) = ^ {
 	static int test = 2;
 	return;
 };
-// CHECK: @block2_block_invoke_3.test = internal global i32
+// CHECK: @block2_block_invoke.test = internal global i32
 int (^block2)(void) = ^ {
 	static int test = 5;
 	return test;
 };
-
+// CHECK: @block3_block_invoke_ZTSi_ZTSj.test = internal global i32
+int (^block3)(int, unsigned) = ^(int, unsigned) {
+	static int test = 5;
+	return test;
+};
diff --git a/libcxxabi/src/demangle/ItaniumDemangle.h b/libcxxabi/src/demangle/ItaniumDemangle.h
--- a/libcxxabi/src/demangle/ItaniumDemangle.h
+++ b/libcxxabi/src/demangle/ItaniumDemangle.h
@@ -5503,8 +5503,7 @@
 // <mangled-name> ::= _Z <encoding>
 //                ::= <type>
 // extension      ::= ___Z <encoding> _block_invoke
-// extension      ::= ___Z <encoding> _block_invoke<decimal-digit>+
-// extension      ::= ___Z <encoding> _block_invoke_<decimal-digit>+
+// extension      ::= ___Z <encoding> _block_invoke<parameter_types>+
 template <typename Derived, typename Alloc>
 Node *AbstractManglingParser<Derived, Alloc>::parse() {
   if (consumeIf("_Z") || consumeIf("__Z")) {
@@ -5524,14 +5523,38 @@
     Node *Encoding = getDerived().parseEncoding();
     if (Encoding == nullptr || !consumeIf("_block_invoke"))
       return nullptr;
-    bool RequireNumber = consumeIf('_');
-    if (parseNumber().empty() && RequireNumber)
-      return nullptr;
+
+    OutputStream ParamOS;
+    if (!initializeOutputStream(nullptr, nullptr, ParamOS, 1024)) {
+      std::terminate();
+    }
+
+    ParamOS += "(";
+    while (consumeIf("_ZTS")) {
+      Node *paramType = getDerived().parseType();
+      if (ParamOS.back() != '(')
+        ParamOS += ", ";
+
+      paramType->print(ParamOS);
+    }
+    ParamOS += ")";
+
     if (look() == '.')
       First = Last;
     if (numLeft() != 0)
       return nullptr;
-    return make<SpecialName>("invocation function for block in ", Encoding);
+
+    OutputStream DescOS;
+    if (!initializeOutputStream(nullptr, nullptr, DescOS, 1024)) {
+      std::terminate();
+    }
+    DescOS << "invocation function for block with params '";
+    DescOS << ParamOS.getBuffer();
+    DescOS << "' in ";
+    DescOS << '\0';
+    std::free(ParamOS.getBuffer());
+
+    return make<SpecialName>(DescOS.getBuffer(), Encoding);
   }
 
   Node *Ty = getDerived().parseType();
@@ -5540,6 +5563,12 @@
   return Ty;
 }
 
+  Node *Ty = getDerived().parseType();
+  if (numLeft() != 0)
+    return nullptr;
+  return Ty;
+}
+
 template <typename Alloc>
 struct ManglingParser : AbstractManglingParser<ManglingParser<Alloc>, Alloc> {
   using AbstractManglingParser<ManglingParser<Alloc>,
diff --git a/llvm/include/llvm/Demangle/ItaniumDemangle.h b/llvm/include/llvm/Demangle/ItaniumDemangle.h
--- a/llvm/include/llvm/Demangle/ItaniumDemangle.h
+++ b/llvm/include/llvm/Demangle/ItaniumDemangle.h
@@ -27,6 +27,8 @@
 #include <cstdlib>
 #include <cstring>
 #include <numeric>
+#include <sstream>
+#include <string>
 #include <utility>
 
 #define FOR_EACH_NODE_KIND(X) \
@@ -5503,8 +5505,7 @@
 // <mangled-name> ::= _Z <encoding>
 //                ::= <type>
 // extension      ::= ___Z <encoding> _block_invoke
-// extension      ::= ___Z <encoding> _block_invoke<decimal-digit>+
-// extension      ::= ___Z <encoding> _block_invoke_<decimal-digit>+
+// extension      ::= ___Z <encoding> _block_invoke<parameter_types>+
 template <typename Derived, typename Alloc>
 Node *AbstractManglingParser<Derived, Alloc>::parse() {
   if (consumeIf("_Z") || consumeIf("__Z")) {
@@ -5524,14 +5525,39 @@
     Node *Encoding = getDerived().parseEncoding();
     if (Encoding == nullptr || !consumeIf("_block_invoke"))
       return nullptr;
-    bool RequireNumber = consumeIf('_');
-    if (parseNumber().empty() && RequireNumber)
-      return nullptr;
+
+    OutputStream ParamOS;
+    if (!initializeOutputStream(nullptr, nullptr, ParamOS, 1024)) {
+      std::terminate();
+    }
+
+    ParamOS += "(";
+    while (consumeIf("_ZTS")) {
+      Node *paramType = getDerived().parseType();
+      if (ParamOS.back() != '(')
+        ParamOS += ", ";
+
+      paramType->print(ParamOS);
+    }
+    ParamOS += ")";
+    ParamOS += '\0';
+
     if (look() == '.')
       First = Last;
     if (numLeft() != 0)
       return nullptr;
-    return make<SpecialName>("invocation function for block in ", Encoding);
+
+    OutputStream DescOS;
+    if (!initializeOutputStream(nullptr, nullptr, DescOS, 1024)) {
+      std::terminate();
+    }
+    DescOS << "invocation function for block with params '";
+    DescOS << ParamOS.getBuffer();
+    DescOS << "' in ";
+    DescOS << '\0';
+    std::free(ParamOS.getBuffer());
+
+    return make<SpecialName>(DescOS.getBuffer(), Encoding);
   }
 
   Node *Ty = getDerived().parseType();
diff --git a/llvm/test/tools/llvm-cxxfilt/invalid.test b/llvm/test/tools/llvm-cxxfilt/invalid.test
--- a/llvm/test/tools/llvm-cxxfilt/invalid.test
+++ b/llvm/test/tools/llvm-cxxfilt/invalid.test
@@ -1,6 +1,7 @@
-RUN: llvm-cxxfilt -n _Z1fi __Z1fi f ___ZSt1ff_block_invoke | FileCheck %s
+RUN: llvm-cxxfilt -n _Z1fi __Z1fi f ___ZSt1ff_block_invoke ___Z7my_mainv_block_invoke_ZTSi_ZTSj_ZTSPVK3sss | FileCheck %s
 
 CHECK: f(int)
 CHECK-NEXT: __Z1fi
 CHECK-NEXT: f
-CHECK-NEXT: invocation function for block in std::f(float)
+CHECK-NEXT: invocation function for block with params '()' in std::f(float)
+CHECK-NEXT: invocation function for block with params '(int, unsigned int, sss const volatile*)' in my_main()
diff --git a/llvm/unittests/Demangle/DemangleTest.cpp b/llvm/unittests/Demangle/DemangleTest.cpp
--- a/llvm/unittests/Demangle/DemangleTest.cpp
+++ b/llvm/unittests/Demangle/DemangleTest.cpp
@@ -16,9 +16,11 @@
   EXPECT_EQ(demangle("_Z3fooi"), "foo(int)");
   EXPECT_EQ(demangle("__Z3fooi"), "foo(int)");
   EXPECT_EQ(demangle("___Z3fooi_block_invoke"),
-            "invocation function for block in foo(int)");
+            "invocation function for block with params '()' in foo(int)");
   EXPECT_EQ(demangle("____Z3fooi_block_invoke"),
-            "invocation function for block in foo(int)");
+            "invocation function for block with params '()' in foo(int)");
+  EXPECT_EQ(demangle("____Z7my_mainv_block_invoke_ZTSi_ZTSj_ZTSPVK3sss"),
+            "invocation function for block with params '(int, unsigned int, sss const volatile*)' in my_main()");
   EXPECT_EQ(demangle("?foo@@YAXH@Z"), "void __cdecl foo(int)");
   EXPECT_EQ(demangle("foo"), "foo");
 }