Index: include/llvm/Support/Compression.h
===================================================================
--- include/llvm/Support/Compression.h
+++ include/llvm/Support/Compression.h
@@ -52,6 +52,8 @@
 
 uint32_t crc32(StringRef Buffer);
 
+StringRef toString(Status Stat);
+
 }  // End of namespace zlib
 
 } // End of namespace llvm
Index: lib/Support/Compression.cpp
===================================================================
--- lib/Support/Compression.cpp
+++ lib/Support/Compression.cpp
@@ -108,3 +108,21 @@
 }
 #endif
 
+StringRef zlib::toString(zlib::Status Stat) {
+  switch (Stat) {
+  case zlib::StatusOK:
+    return "";
+  case zlib::StatusUnsupported:
+    return "zlib is unavailable";
+  case zlib::StatusOutOfMemory:
+    return "there was not enough memory";
+  case zlib::StatusBufferTooShort:
+    return "there was not enough room in the output buffer";
+  case zlib::StatusInvalidArg:
+    return "invalid input parameter";
+  case zlib::StatusInvalidData:
+    return "data was corrupted or incomplete";
+  default:
+    llvm_unreachable("status unknown");
+  }
+}
Index: unittests/Support/CompressionTest.cpp
===================================================================
--- unittests/Support/CompressionTest.cpp
+++ unittests/Support/CompressionTest.cpp
@@ -67,4 +67,15 @@
 
 #endif
 
+TEST(CompressionTest, ZlibMessages) {
+  EXPECT_EQ("", zlib::toString(zlib::StatusOK));
+  EXPECT_EQ("zlib is unavailable", zlib::toString(zlib::StatusUnsupported));
+  EXPECT_EQ("there was not enough memory",
+            zlib::toString(zlib::StatusOutOfMemory));
+  EXPECT_EQ("there was not enough room in the output buffer",
+            zlib::toString(zlib::StatusBufferTooShort));
+  EXPECT_EQ("invalid input parameter", zlib::toString(zlib::StatusInvalidArg));
+  EXPECT_EQ("data was corrupted or incomplete",
+            zlib::toString(zlib::StatusInvalidData));
+}
 }