4 files changed, 56 insertions, 17 deletions

diff --git a/tools/pnacl-llc/SRPCStreamer.cpp b/tools/pnacl-llc/SRPCStreamer.cpp
index e6546aef5f..ddec846d2c 100644
--- a/tools/pnacl-llc/SRPCStreamer.cpp
+++ b/tools/pnacl-llc/SRPCStreamer.cpp
@@ -119,19 +119,30 @@ llvm::DataStreamer *SRPCStreamer::init(void *(*Callback)(void *), void *arg,
 }
 
 size_t SRPCStreamer::gotChunk(unsigned char *bytes, size_t len) {
-  if (Error) return 0;
+  if (__sync_fetch_and_add(&Error, 0)) return 0; // Atomic read.
   return Q.PutBytes(bytes, len);
 }
 
 int SRPCStreamer::streamEnd(std::string *ErrMsg) {
   Q.SetDone();
   int err = pthread_join(CompileThread, NULL);
-  if (err) {
+  __sync_synchronize();
+  if (Error) {
+    if (ErrMsg)
+      *ErrMsg = std::string("PNaCl Translator Error: " + ErrorMessage);
+    return 1;
+  } else if (err) {
     if (ErrMsg) *ErrMsg = std::string(strerror(errno));
     return err;
   }
-  if (Error && ErrMsg) *ErrMsg = std::string("compile failed.");
-  return Error;
+  return 0;
+}
+
+void SRPCStreamer::setFatalError(const std::string& message) {
+  __sync_fetch_and_add(&Error, 1);
+  ErrorMessage = message;
+  __sync_synchronize();
+  pthread_exit(NULL);
 }
 
 #endif // __native_client__
diff --git a/tools/pnacl-llc/SRPCStreamer.h b/tools/pnacl-llc/SRPCStreamer.h
index 805552be1f..bde86e5d9f 100644
--- a/tools/pnacl-llc/SRPCStreamer.h
+++ b/tools/pnacl-llc/SRPCStreamer.h
@@ -98,11 +98,12 @@ public:
   size_t gotChunk(unsigned char *bytes, size_t len);
   // Called by the RPC thread. Wait for the compilation thread to finish.
   int streamEnd(std::string *ErrMsg);
-  // Called by the compilation thread. Signal that there was a compilation
-  // error so the RPC thread can abort the stream.
-  void setError() { Error = true; }
+  // Called by the compilation thread. Set the error condition and also
+  // terminate the thread.
+  void setFatalError(const std::string& message);
 private:
-  bool Error;
+  int Error;
+  std::string ErrorMessage;
   QueueStreamer Q;
   pthread_t CompileThread;
 };
diff --git a/tools/pnacl-llc/pnacl-llc.cpp b/tools/pnacl-llc/pnacl-llc.cpp
index 31d546ab3e..cac4fa83a4 100644
--- a/tools/pnacl-llc/pnacl-llc.cpp
+++ b/tools/pnacl-llc/pnacl-llc.cpp
@@ -28,6 +28,7 @@
 #include "llvm/PassManager.h"
 #include "llvm/Support/CommandLine.h"
 #include "llvm/Support/Debug.h"
+#include "llvm/Support/ErrorHandling.h"
 #include "llvm/Support/FormattedStream.h"
 #include "llvm/Support/Host.h"
 #include "llvm/Support/ManagedStatic.h"
@@ -52,6 +53,7 @@ using namespace llvm;
 int srpc_main(int argc, char **argv);
 int getObjectFileFD();
 DataStreamer *getNaClBitcodeStreamer();
+fatal_error_handler_t getSRPCErrorHandler();
 #endif
 
 cl::opt<NaClFileFormat>
@@ -215,6 +217,10 @@ int llc_main(int argc, char **argv) {
   LLVMContext &Context = getGlobalContext();
   llvm_shutdown_obj Y;  // Call llvm_shutdown() on exit.
 
+#if defined(__native_client__)
+  install_fatal_error_handler(getSRPCErrorHandler(), NULL);
+#endif
+
   // Initialize targets first, so that --version shows registered targets.
   InitializeAllTargets();
   InitializeAllTargetMCs();
@@ -252,11 +258,15 @@ int llc_main(int argc, char **argv) {
 static void CheckABIVerifyErrors(PNaClABIErrorReporter &Reporter,
                                  const Twine &Name) {
   if (PNaClABIVerify && Reporter.getErrorCount() > 0) {
-    errs() << (PNaClABIVerifyFatalErrors ? "ERROR: " : "WARNING: ");
-    errs() << Name << " is not valid PNaCl bitcode:\n";
-    Reporter.printErrors(errs());
-    if (PNaClABIVerifyFatalErrors)
-      exit(1);
+    std::string errors;
+    raw_string_ostream os(errors);
+    os << (PNaClABIVerifyFatalErrors ? "ERROR: " : "WARNING: ");
+    os << Name << " is not valid PNaCl bitcode:\n";
+    Reporter.printErrors(os);
+    if (PNaClABIVerifyFatalErrors) {
+      report_fatal_error(os.str());
+    }
+    errs() << os.str();
   }
   Reporter.reset();
 }
@@ -273,11 +283,12 @@ static int compileModule(StringRef ProgramName, LLVMContext &Context) {
 #if defined(__native_client__)
   if (LazyBitcode) {
     std::string StrError;
+    std::string DisplayFilename("<PNaCl-translated pexe>");
     M.reset(getNaClStreamedBitcodeModule(
-        std::string("<SRPC stream>"),
+        DisplayFilename,
         getNaClBitcodeStreamer(), Context, &StrError));
     if (!StrError.empty())
-      Err = SMDiagnostic(InputFilename, SourceMgr::DK_Error, StrError);
+      Err = SMDiagnostic(DisplayFilename, SourceMgr::DK_Error, StrError);
   } else {
     llvm_unreachable("native client SRPC only supports streaming");
   }
@@ -287,8 +298,13 @@ static int compileModule(StringRef ProgramName, LLVMContext &Context) {
 
   mod = M.get();
   if (mod == 0) {
+#if defined(__native_client__)
+    report_fatal_error(Err.getMessage());
+#else
+    // Err.print is prettier, so use it for the non-sandboxed translator.
     Err.print(ProgramName.data(), errs());
     return 1;
+#endif
   }
 
   if (PNaClABIVerify) {
diff --git a/tools/pnacl-llc/srpc_main.cpp b/tools/pnacl-llc/srpc_main.cpp
index 87178c2038..46d79ce441 100644
--- a/tools/pnacl-llc/srpc_main.cpp
+++ b/tools/pnacl-llc/srpc_main.cpp
@@ -32,6 +32,7 @@
 #include "llvm/ADT/OwningPtr.h"
 #include "llvm/ADT/STLExtras.h"
 #include "llvm/Option/Option.h"
+#include "llvm/Support/ErrorHandling.h"
 #include "llvm/Support/system_error.h"
 
 using namespace llvm;
@@ -202,8 +203,10 @@ void *run_streamed(void *arg) {
   StreamingThreadData *data = reinterpret_cast<StreamingThreadData *>(arg);
   data->CmdLineVec()->push_back("-streaming-bitcode");
   if (DoTranslate(data->CmdLineVec(), data->ObjectFD()) != 0) {
-    fprintf(stderr, "DoTranslate failed.\n");
-    srpc_streamer->setError();
+    // llc_main only returns 1 (as opposed to calling report_fatal_error)
+    // in conditions we never expect to see in the browser (e.g. bad
+    // command-line flags).
+    srpc_streamer->setFatalError("llc_main unspecified failure");
     return NULL;
   }
   delete data;
@@ -351,6 +354,14 @@ int getObjectFileFD() { return object_file_fd; }
 
 DataStreamer *getNaClBitcodeStreamer() { return NaClBitcodeStreamer; }
 
+// Called from the compilation thread
+void FatalErrorHandler(void *user_data, const std::string& reason,
+                       bool gen_crash_diag) {
+  srpc_streamer->setFatalError(reason);
+}
+
+fatal_error_handler_t getSRPCErrorHandler() { return FatalErrorHandler; }
+
 int srpc_main(int argc, char **argv) {
   if (!NaClSrpcModuleInit()) {
     return 1;