SPARC: Register null target streamer

Fixes null dereference in emitFunctionBodyStart for 64-bit

Author: arsenm

llvm/lib/Target/Sparc/MCTargetDesc/SparcMCTargetDesc.cpp

@@ -84,6 +84,10 @@ static MCTargetStreamer *createTargetAsmStreamer(MCStreamer &S,
   return new SparcTargetAsmStreamer(S, OS);
 }
 
+static MCTargetStreamer *createNullTargetStreamer(MCStreamer &S) {
+  return new SparcTargetStreamer(S);
+}
+
 static MCInstPrinter *createSparcMCInstPrinter(const Triple &T,
                                                unsigned SyntaxVariant,
                                                const MCAsmInfo &MAI,
@@ -122,6 +126,9 @@ extern "C" LLVM_EXTERNAL_VISIBILITY void LLVMInitializeSparcTargetMC() {
     // Register the asm streamer.
     TargetRegistry::RegisterAsmTargetStreamer(*T, createTargetAsmStreamer);
 
+    // Register the null streamer.
+    TargetRegistry::RegisterNullTargetStreamer(*T, createNullTargetStreamer);
+
     // Register the MCInstPrinter
     TargetRegistry::RegisterMCInstPrinter(*T, createSparcMCInstPrinter);
   }

llvm/lib/Target/Sparc/MCTargetDesc/SparcTargetStreamer.h

@@ -22,9 +22,9 @@ class SparcTargetStreamer : public MCTargetStreamer {
 public:
   SparcTargetStreamer(MCStreamer &S);
   /// Emit ".register <reg>, #ignore".
-  virtual void emitSparcRegisterIgnore(unsigned reg) = 0;
+  virtual void emitSparcRegisterIgnore(unsigned reg){};
   /// Emit ".register <reg>, #scratch".
-  virtual void emitSparcRegisterScratch(unsigned reg) = 0;
+  virtual void emitSparcRegisterScratch(unsigned reg){};
 };
 
 // This part is for ascii assembly output

llvm/test/CodeGen/SPARC/64bit.ll

@@ -1,5 +1,6 @@
 ; RUN: llc < %s -march=sparcv9 -mattr=+popc -disable-sparc-delay-filler -disable-sparc-leaf-proc | FileCheck %s
 ; RUN: llc < %s -march=sparcv9 -mattr=+popc | FileCheck %s -check-prefix=OPT
+; RUN: llc %s -march=sparcv9 -mattr=+popc -filetype=null
 
 ; CHECK-LABEL: ret2:
 ; CHECK: mov %i1, %i0