PowerPC: add EmitTCEntry class for TOC creation

This patch replaces the EmitRawText by a EmitTCEntry class (specialized for
each Streamer) in PowerPC64 TOC entry creation.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@165940 91177308-0d34-0410-b5e6-96231b3b80d8

include/llvm/MC/MCStreamer.h

@@ -554,6 +554,11 @@ namespace llvm {
     virtual void EmitRegSave(const SmallVectorImpl<unsigned> &RegList,
                              bool isVector);
 
+    /// PPC-related methods.
+    /// FIXME: Eventually replace it with some "target MC streamer" and move
+    /// these methods there.
+    virtual void EmitTCEntry(const MCSymbol &S);
+
     /// FinishImpl - Streamer specific finalization.
     virtual void FinishImpl() = 0;
     /// Finish - Finish emission of machine code.

lib/MC/MCAsmStreamer.cpp

@@ -251,6 +251,7 @@ public:
   virtual void EmitPad(int64_t Offset);
   virtual void EmitRegSave(const SmallVectorImpl<unsigned> &RegList, bool);
 
+  virtual void EmitTCEntry(const MCSymbol &S);
 
   virtual void EmitInstruction(const MCInst &Inst);
 
@@ -1299,6 +1300,14 @@ void MCAsmStreamer::EmitRegSave(const SmallVectorImpl<unsigned> &RegList,
   EmitEOL();
 }
 
+void MCAsmStreamer::EmitTCEntry(const MCSymbol &S) {
+  OS << "\t.tc ";
+  OS << S.getName();
+  OS << "[TC],";
+  OS << S.getName();
+  EmitEOL();
+}
+
 void MCAsmStreamer::EmitInstruction(const MCInst &Inst) {
   assert(getCurrentSection() && "Cannot emit contents before setting section!");
 

lib/MC/MCELFStreamer.cpp

@@ -103,6 +103,8 @@ public:
 
   virtual void EmitFileDirective(StringRef Filename);
 
+  virtual void EmitTCEntry(const MCSymbol &S);
+
   virtual void FinishImpl();
 
 private:
@@ -469,6 +471,12 @@ void MCELFStreamer::FinishImpl() {
   this->MCObjectStreamer::FinishImpl();
 }
 
+void MCELFStreamer::EmitTCEntry(const MCSymbol &S)
+{
+  // Creates a R_PPC64_TOC relocation
+  MCObjectStreamer::EmitSymbolValue(&S, 8, 0);
+}
+
 MCStreamer *llvm::createELFStreamer(MCContext &Context, MCAsmBackend &MAB,
                                     raw_ostream &OS, MCCodeEmitter *CE,
                                     bool RelaxAll, bool NoExecStack) {

lib/MC/MCStreamer.cpp

@@ -561,6 +561,10 @@ void MCStreamer::EmitRegSave(const SmallVectorImpl<unsigned> &RegList, bool) {
   abort();
 }
 
+void MCStreamer::EmitTCEntry(const MCSymbol &S) {
+  llvm_unreachable("Unsupported method");
+}
+
 /// EmitRawText - If this file is backed by an assembly streamer, this dumps
 /// the specified string in the output .s file.  This capability is
 /// indicated by the hasRawTextSupport() predicate.

lib/Target/PowerPC/PPCAsmPrinter.cpp

@@ -451,8 +451,8 @@ bool PPCLinuxAsmPrinter::doFinalization(Module &M) {
     for (DenseMap<MCSymbol*, MCSymbol*>::iterator I = TOC.begin(),
          E = TOC.end(); I != E; ++I) {
       OutStreamer.EmitLabel(I->second);
-      OutStreamer.EmitRawText("\t.tc " + Twine(I->first->getName()) +
-                              "[TC]," + I->first->getName());
+      MCSymbol *S = OutContext.GetOrCreateSymbol(I->first->getName());
+      OutStreamer.EmitTCEntry(*S);
     }
   }