Add InlineAsmDiagnosticHandler for bitcode input

[steven_wu]

Summary

This is another attempt to silence the crash report for invalid inline asm
in bitcode input to clang.
Different from http://reviews.llvm.org/D7476, this patch installs an
InlineAsmDiagnosticsHandler to avoid the crash report. The handler will
simply print the same error message that will print from the backend.

[• rafael]

Please also CHECK for what is actually printed.
LGTM with that.

[steven_wu]

Thanks Rafael. Edit the test case and committed in r228898.
Have you got any chance to look at my email from the thread of r226503?

Steven

lib/CodeGen/CodeGenAction.cpp

CodeGenAction::CreateASTConsumer(CompilerInstance &CI, StringRef InFile) {
   std::unique_ptr<BackendConsumer> Result(new BackendConsumer(
       BA, CI.getDiagnostics(), CI.getCodeGenOpts(), CI.getTargetOpts(),
       CI.getLangOpts(), CI.getFrontendOpts().ShowTimers, InFile,
       LinkModuleToUse, OS.release(), *VMContext, CoverageInfo));
   BEConsumer = Result.get();
   return std::move(Result);
 }
 
+static void BitcodeInlineAsmDiagHandler(const llvm::SMDiagnostic &SM,
+                                         void *Context,
+                                         unsigned LocCookie) {
+  SM.print(nullptr, llvm::errs());
+}
+
 void CodeGenAction::ExecuteAction() {
   // If this is an IR file, we have to treat it specially.
   if (getCurrentFileKind() == IK_LLVM_IR) {
     BackendAction BA = static_cast<BackendAction>(Act);
     CompilerInstance &CI = getCompilerInstance();
     raw_ostream *OS = GetOutputStream(CI, getCurrentFile(), BA);
     if (BA != Backend_EmitNothing && !OS)
       return;
if (getCurrentFileKind() == IK_LLVM_IR) {
     const TargetOptions &TargetOpts = CI.getTargetOpts();
     if (TheModule->getTargetTriple() != TargetOpts.Triple) {
       CI.getDiagnostics().Report(SourceLocation(),
                                  diag::warn_fe_override_module)
           << TargetOpts.Triple;
       TheModule->setTargetTriple(TargetOpts.Triple);
     }
 
+    LLVMContext &Ctx = TheModule->getContext();
+    Ctx.setInlineAsmDiagnosticHandler(BitcodeInlineAsmDiagHandler);
     EmitBackendOutput(CI.getDiagnostics(), CI.getCodeGenOpts(), TargetOpts,
                       CI.getLangOpts(), CI.getTarget().getTargetDescription(),
                       TheModule.get(), BA, OS);
     return;
   }
 
   // Otherwise follow the normal AST path.
   this->ASTFrontendAction::ExecuteAction();

test/CodeGen/asm-errors.c

 // REQUIRES: x86-registered-target
 
 // RUN: true
 // UN: not %clang_cc1 -triple i386-apple-darwin10 -emit-obj %s -o /dev/null > %t 2>&1
 // UN: FileCheck %s < %t
+// RUN: %clang_cc1 -triple i386-apple-darwin10 -emit-llvm-bc %s -o %t.bc
+// RUN: %clang_cc1 -triple i386-apple-darwin10 -emit-obj %t.bc -o /dev/null 2>&1 | \
+// RUN:   FileCheck --check-prefix=CRASH-REPORT %s
+// CRASH-REPORT-NOT: note: diagnostic msg:
 
 int test1(int X) {
 // CHECK: error: invalid instruction mnemonic 'abc'
   __asm__ ("abc incl    %0" : "+r" (X));
   return X;
 }