Remove Emscripten support

lib/CodeGen/ItaniumCXXABI.cpp

 //===------- ItaniumCXXABI.cpp - Emit LLVM Code from ASTs for a Module ----===//
 //
 //                     The LLVM Compiler Infrastructure
 //
 // This file is distributed under the University of Illinois Open Source
 // License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 //
 // This provides C++ code generation targeting the Itanium C++ ABI.  The class
@@ skipping 340 matching lines @@
   // Note that AArch64 uses the generic ItaniumCXXABI class since it doesn't
   // include the other 32-bit ARM oddities: constructor/destructor return values
   // and array cookies.
   case TargetCXXABI::GenericAArch64:
     return new ItaniumCXXABI(CGM, /* UseARMMethodPtrABI = */ true,
                              /* UseARMGuardVarABI = */ true);
 
   case TargetCXXABI::GenericMIPS:
     return new ItaniumCXXABI(CGM, /* UseARMMethodPtrABI = */ true);
 
-  // @LOCALMOD-START Emscripten
-  case TargetCXXABI::Emscripten:
-    // Use ARM-style method pointers so that generated code does not assume
-    // anything about the alignment of function pointers.
-    return new ItaniumCXXABI(CGM, /* UseARMMethodPtrABI = */ true,
-                             /* UseARMGuardVarABI = */ false);
-  // @LOCALMOD-END Emscripten
-
   case TargetCXXABI::GenericItanium:
     if (CGM.getContext().getTargetInfo().getTriple().getArch()
         == llvm::Triple::le32) {
       // For PNaCl, use ARM-style method pointers so that PNaCl code
       // does not assume anything about the alignment of function
       // pointers.
       return new ItaniumCXXABI(CGM, /* UseARMMethodPtrABI = */ true,
                                /* UseARMGuardVarABI = */ false);
     }
     return new ItaniumCXXABI(CGM);
@@ skipping 3256 matching lines @@
 llvm::CallInst *
 ItaniumCXXABI::emitTerminateForUnexpectedException(CodeGenFunction &CGF,
                                                    llvm::Value *Exn) {
   // In C++, we want to call __cxa_begin_catch() before terminating.
   if (Exn) {
     assert(CGF.CGM.getLangOpts().CPlusPlus);
     return CGF.EmitNounwindRuntimeCall(getClangCallTerminateFn(CGF.CGM), Exn);
   }
   return CGF.EmitNounwindRuntimeCall(CGF.CGM.getTerminateFn());
 }