[MIPS] Add support for direct-to-nacl in Clang

lib/Basic/Targets.cpp

 //===--- Targets.cpp - Implement -arch option and targets -----------------===//
 //
 //                     The LLVM Compiler Infrastructure
 //
 // This file is distributed under the University of Illinois Open Source
 // License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 //
 // This file implements construction of a TargetInfo object from a
@@ skipping 6547 matching lines @@
   Names = nullptr;
   NumNames = 0;
 }
 
 void PNaClTargetInfo::getGCCRegAliases(const GCCRegAlias *&Aliases,
                                        unsigned &NumAliases) const {
   Aliases = nullptr;
   NumAliases = 0;
 }
 
+// We attempt to use PNaCl (le32) frontend and Mips32EL backend.
+class NaClMips32ELTargetInfo : public Mips32ELTargetInfo {
+public:
+  NaClMips32ELTargetInfo(const llvm::Triple &Triple) :
+    Mips32ELTargetInfo(Triple)  {
+      MaxAtomicPromoteWidth = MaxAtomicInlineWidth = 0;
+  }
+
+  BuiltinVaListKind getBuiltinVaListKind() const override {
+    return TargetInfo::PNaClABIBuiltinVaList;
+  }
+};
+
 class Le64TargetInfo : public TargetInfo {
   static const Builtin::Info BuiltinInfo[];
 
 public:
   Le64TargetInfo(const llvm::Triple &Triple) : TargetInfo(Triple) {
     BigEndian = false;
     NoAsmVariants = true;
     LongWidth = LongAlign = PointerWidth = PointerAlign = 64;
     MaxAtomicPromoteWidth = MaxAtomicInlineWidth = 64;
     DescriptionString =
@@ skipping 346 matching lines @@
     switch (os) {
     case llvm::Triple::Linux:
       return new LinuxTargetInfo<Mips32ELTargetInfo>(Triple);
     case llvm::Triple::RTEMS:
       return new RTEMSTargetInfo<Mips32ELTargetInfo>(Triple);
     case llvm::Triple::FreeBSD:
       return new FreeBSDTargetInfo<Mips32ELTargetInfo>(Triple);
     case llvm::Triple::NetBSD:
       return new NetBSDTargetInfo<Mips32ELTargetInfo>(Triple);
     case llvm::Triple::NaCl:
-      return new NaClTargetInfo<Mips32ELTargetInfo>(Triple);
+      return new NaClTargetInfo<NaClMips32ELTargetInfo>(Triple);
     default:
       return new Mips32ELTargetInfo(Triple);
     }
 
   case llvm::Triple::mips64:
     switch (os) {
     case llvm::Triple::Linux:
       return new LinuxTargetInfo<Mips64EBTargetInfo>(Triple);
     case llvm::Triple::RTEMS:
       return new RTEMSTargetInfo<Mips64EBTargetInfo>(Triple);
@@ skipping 307 matching lines @@
   // need to pass the minuses.
   Opts->Features.clear();
   for (llvm::StringMap<bool>::const_iterator it = Features.begin(),
          ie = Features.end(); it != ie; ++it)
     Opts->Features.push_back((it->second ? "+" : "-") + it->first().str());
   if (!Target->handleTargetFeatures(Opts->Features, Diags))
     return nullptr;
 
   return Target.release();
 }