Split the object streamer callback in one per file format.

There are two main advantages to doing this

* Targets that only need to handle one of the formats specially don't have
  to worry about the others. For example, x86 now only registers a
  constructor for the COFF streamer.

* Changes to the arguments passed to one format constructor will not impact
  the other formats.

llvm-svn: 232699
diff --git a/llvm/lib/Target/X86/MCTargetDesc/X86MCTargetDesc.cpp b/llvm/lib/Target/X86/MCTargetDesc/X86MCTargetDesc.cpp
index afcc953..2e1644d 100644
--- a/llvm/lib/Target/X86/MCTargetDesc/X86MCTargetDesc.cpp
+++ b/llvm/lib/Target/X86/MCTargetDesc/X86MCTargetDesc.cpp
@@ -344,22 +344,6 @@
   return X;
 }
 
-static MCStreamer *createMCStreamer(const Triple &T, MCContext &Ctx,
-                                    MCAsmBackend &MAB, raw_ostream &OS,
-                                    MCCodeEmitter *Emitter,
-                                    const MCSubtargetInfo &STI, bool RelaxAll) {
-  switch (T.getObjectFormat()) {
-  default: llvm_unreachable("unsupported object format");
-  case Triple::MachO:
-    return createMachOStreamer(Ctx, MAB, OS, Emitter, RelaxAll);
-  case Triple::COFF:
-    assert(T.isOSWindows() && "only Windows COFF is supported");
-    return createX86WinCOFFStreamer(Ctx, MAB, Emitter, OS, RelaxAll);
-  case Triple::ELF:
-    return createELFStreamer(Ctx, MAB, OS, Emitter, RelaxAll);
-  }
-}
-
 static MCInstPrinter *createX86MCInstPrinter(const Target &T,
                                              unsigned SyntaxVariant,
                                              const MCAsmInfo &MAI,
@@ -414,7 +398,7 @@
     TargetRegistry::RegisterMCCodeEmitter(*T, createX86MCCodeEmitter);
 
     // Register the object streamer.
-    TargetRegistry::RegisterMCObjectStreamer(*T, createMCStreamer);
+    TargetRegistry::RegisterCOFFStreamer(*T, createX86WinCOFFStreamer);
 
     // Register the MCInstPrinter.
     TargetRegistry::RegisterMCInstPrinter(*T, createX86MCInstPrinter);
diff --git a/llvm/lib/Target/X86/MCTargetDesc/X86MCTargetDesc.h b/llvm/lib/Target/X86/MCTargetDesc/X86MCTargetDesc.h
index fa69ce9..fb77554 100644
--- a/llvm/lib/Target/X86/MCTargetDesc/X86MCTargetDesc.h
+++ b/llvm/lib/Target/X86/MCTargetDesc/X86MCTargetDesc.h
@@ -85,12 +85,12 @@
 MCAsmBackend *createX86_64AsmBackend(const Target &T, const MCRegisterInfo &MRI,
                                      StringRef TT, StringRef CPU);
 
-/// createX86WinCOFFStreamer - Construct an X86 Windows COFF machine code
-/// streamer which will generate PE/COFF format object files.
+/// Construct an X86 Windows COFF machine code streamer which will generate
+/// PE/COFF format object files.
 ///
 /// Takes ownership of \p AB and \p CE.
 MCStreamer *createX86WinCOFFStreamer(MCContext &C, MCAsmBackend &AB,
-                                     MCCodeEmitter *CE, raw_ostream &OS,
+                                     raw_ostream &OS, MCCodeEmitter *CE,
                                      bool RelaxAll);
 
 /// createX86MachObjectWriter - Construct an X86 Mach-O object writer.
diff --git a/llvm/lib/Target/X86/MCTargetDesc/X86WinCOFFStreamer.cpp b/llvm/lib/Target/X86/MCTargetDesc/X86WinCOFFStreamer.cpp
index 5f1596c..5690efe 100644
--- a/llvm/lib/Target/X86/MCTargetDesc/X86WinCOFFStreamer.cpp
+++ b/llvm/lib/Target/X86/MCTargetDesc/X86WinCOFFStreamer.cpp
@@ -48,13 +48,11 @@
 }
 }
 
-namespace llvm {
-MCStreamer *createX86WinCOFFStreamer(MCContext &C, MCAsmBackend &AB,
-                                     MCCodeEmitter *CE, raw_ostream &OS,
-                                     bool RelaxAll) {
+MCStreamer *llvm::createX86WinCOFFStreamer(MCContext &C, MCAsmBackend &AB,
+                                           raw_ostream &OS, MCCodeEmitter *CE,
+                                           bool RelaxAll) {
   X86WinCOFFStreamer *S = new X86WinCOFFStreamer(C, AB, CE, OS);
   S->getAssembler().setRelaxAll(RelaxAll);
   return S;
 }
-}