Index: lib/sanitizer_common/sanitizer_symbolizer_internal.h
===================================================================
--- lib/sanitizer_common/sanitizer_symbolizer_internal.h
+++ lib/sanitizer_common/sanitizer_symbolizer_internal.h
@@ -28,7 +28,7 @@
 const char *ExtractTokenUpToDelimiter(const char *str, const char *delimiter,
                                       char **result);
 
-const char *DemangleCXXABI(const char *name);
+const char *DemangleCXXAndSwift(const char *name);
 
 // SymbolizerTool is an interface that is implemented by individual "tools"
 // that can perform symbolication (external llvm-symbolizer, libbacktrace,
Index: lib/sanitizer_common/sanitizer_symbolizer_mac.cc
===================================================================
--- lib/sanitizer_common/sanitizer_symbolizer_mac.cc
+++ lib/sanitizer_common/sanitizer_symbolizer_mac.cc
@@ -32,7 +32,7 @@
   Dl_info info;
   int result = dladdr((const void *)addr, &info);
   if (!result) return false;
-  const char *demangled = DemangleCXXABI(info.dli_sname);
+  const char *demangled = DemangleCXXAndSwift(info.dli_sname);
   stack->info.function = demangled ? internal_strdup(demangled) : nullptr;
   return true;
 }
@@ -41,7 +41,7 @@
   Dl_info info;
   int result = dladdr((const void *)addr, &info);
   if (!result) return false;
-  const char *demangled = DemangleCXXABI(info.dli_sname);
+  const char *demangled = DemangleCXXAndSwift(info.dli_sname);
   datainfo->name = internal_strdup(demangled);
   datainfo->start = (uptr)info.dli_saddr;
   return true;
Index: lib/sanitizer_common/sanitizer_symbolizer_posix_libcdep.cc
===================================================================
--- lib/sanitizer_common/sanitizer_symbolizer_posix_libcdep.cc
+++ lib/sanitizer_common/sanitizer_symbolizer_posix_libcdep.cc
@@ -26,6 +26,7 @@
 #include "sanitizer_symbolizer_libbacktrace.h"
 #include "sanitizer_symbolizer_mac.h"
 
+#include <dlfcn.h>   // for dlsym()
 #include <errno.h>
 #include <stdlib.h>
 #include <sys/wait.h>
@@ -61,6 +62,38 @@
   return name;
 }
 
+// Attempts to demangle a Swift name. The demangler will return nullptr
+/// if a non-Swift name is passed in.
+const char *DemangleSwift(const char *name) {
+  // Not to call dlsym every time we demangle, check if we are dealing with
+  // Swift mangled name first.
+  if (name[0] != '_' || name[1] != 'T') {
+    return nullptr;
+  }
+
+  // As of now, there are no headers for the Swift runtime. Once they are
+  // present, we will weakly link since we do not require Swift runtime to be
+  // linked.
+  typedef char *(*swift_demangle_ft)(const char *mangledName,
+                                     size_t mangledNameLength,
+                                     char *outputBuffer,
+                                     size_t *outputBufferSize,
+                                     uint32_t flags);
+  swift_demangle_ft swift_demangle_f =
+    (swift_demangle_ft) dlsym(RTLD_DEFAULT, "swift_demangle");
+  if (swift_demangle_f)
+    return swift_demangle_f(name, internal_strlen(name), 0, 0, 0);
+
+  return nullptr;
+}
+
+const char *DemangleCXXAndSwift(const char *name) {
+  CHECK(name);
+  if (const char *swift_demangled_name = DemangleSwift(name))
+    return swift_demangled_name;
+  return DemangleCXXABI(name);
+}
+
 bool SymbolizerProcess::StartSymbolizerSubprocess() {
   if (!FileExists(path_)) {
     if (!reported_invalid_path_) {
@@ -364,7 +397,7 @@
 #endif  // SANITIZER_SUPPORTS_WEAK_HOOKS
 
 const char *Symbolizer::PlatformDemangle(const char *name) {
-  return DemangleCXXABI(name);
+  return DemangleCXXAndSwift(name);
 }
 
 void Symbolizer::PlatformPrepareForSandboxing() {}
Index: lib/sanitizer_common/tests/sanitizer_symbolizer_test.cc
===================================================================
--- lib/sanitizer_common/tests/sanitizer_symbolizer_test.cc
+++ lib/sanitizer_common/tests/sanitizer_symbolizer_test.cc
@@ -55,4 +55,13 @@
   InternalFree(token);
 }
 
+TEST(Symbolizer, DemangleCXXAndSwift) {
+  // The Swift name will only be demangled if the Swift runtime is linked in.
+  EXPECT_STREQ("_TtSd", DemangleCXXAndSwift("_TtSd"));
+  // Check that the rest demangles properly.
+  EXPECT_STREQ("f1(char*, int)", DemangleCXXAndSwift("_Z2f1Pci"));
+  EXPECT_STREQ("foo", DemangleCXXAndSwift("foo"));
+  EXPECT_STREQ("", DemangleCXXAndSwift(""));
+}
+
 }  // namespace __sanitizer