Index: tools/llvm-as-parasitic-coverage-repro/CMakeLists.txt
===================================================================
--- tools/llvm-as-parasitic-coverage-repro/CMakeLists.txt	(revision 0)
+++ tools/llvm-as-parasitic-coverage-repro/CMakeLists.txt	(working copy)
@@ -0,0 +1,10 @@
+if( LLVM_USE_SANITIZE_COVERAGE )
+  set(LLVM_LINK_COMPONENTS
+      AsmParser
+      BitWriter
+      Core
+      Support
+      )
+  add_llvm_tool(llvm-as-parasitic-coverage-repro 
+                llvm-as-parasitic-coverage-repro.cpp)
+endif()
Index: tools/llvm-as-parasitic-coverage-repro/llvm-as-parasitic-coverage-repro.cpp
===================================================================
--- tools/llvm-as-parasitic-coverage-repro/llvm-as-parasitic-coverage-repro.cpp	(revision 0)
+++ tools/llvm-as-parasitic-coverage-repro/llvm-as-parasitic-coverage-repro.cpp	(working copy)
@@ -0,0 +1,28 @@
+#include "llvm/ADT/StringRef.h"
+#include "llvm/AsmParser/Parser.h"
+#include "llvm/IR/LLVMContext.h"
+#include "llvm/IR/Module.h"
+#include "llvm/IR/Verifier.h"
+#include "llvm/Support/ErrorHandling.h"
+#include "llvm/Support/MemoryBuffer.h"
+#include "llvm/Support/raw_ostream.h"
+#include "llvm/Support/SourceMgr.h"
+using namespace llvm;
+extern "C" void TestOneInput() {
+  StringRef Input("declare i32 @llvm.x86.sse42.crc32.32.8(i32, i8) nounwind");
+  std::unique_ptr<MemoryBuffer> MemBuf = MemoryBuffer::getMemBufferCopy(Input);
+  SMDiagnostic Err;
+  std::unique_ptr<LLVMContext> Context(new LLVMContext);
+  std::unique_ptr<Module> M;
+  M = parseAssembly(MemBuf->getMemBufferRef(), Err, *Context.get());
+  if (M.get())
+    verifyModule(*M.get());
+}
+
+int main(int argc, char **argv) {
+  assert(argc == 2);
+  int NumIter = atoi(argv[1]);
+  for (int i = 0; i < NumIter; i++) {
+    TestOneInput();
+  }
+}