Implement clang support for indirect branch and address of label

using the new LLVM support for this.  This is temporarily hiding
behind horrible and ugly #ifdefs until the time when the optimizer
is stable (hopefully a week or so).  Until then, lets make it "opt in" :)

llvm-svn: 85446

1 files changed, 18 insertions, 0 deletions

diff --git a/clang/lib/CodeGen/CodeGenFunction.h b/clang/lib/CodeGen/CodeGenFunction.h
index f290571b7d7..1fba3f971e7 100644
--- a/clang/lib/CodeGen/CodeGenFunction.h
+++ b/clang/lib/CodeGen/CodeGenFunction.h
@@ -183,13 +183,26 @@ public:
   void PopConditionalTempDestruction();
 
 private:
+#ifndef USEINDIRECTBRANCH
   CGDebugInfo* DebugInfo;
+#else
+  CGDebugInfo *DebugInfo;
+#endif
 
+#ifndef USEINDIRECTBRANCH
   /// LabelIDs - Track arbitrary ids assigned to labels for use in implementing
   /// the GCC address-of-label extension and indirect goto. IDs are assigned to
   /// labels inside getIDForAddrOfLabel().
   std::map<const LabelStmt*, unsigned> LabelIDs;
+#else
+  /// IndirectBranch - The first time an indirect goto is seen we create a
+  /// block with an indirect branch.  Every time we see the address of a label
+  /// taken, we add the label to the indirect goto.  Every subsequent indirect
+  /// goto is codegen'd as a jump to the IndirectBranch's basic block.
+  llvm::IndirectBrInst *IndirectBranch;
+#endif
 
+#ifndef USEINDIRECTBRANCH
   /// IndirectGotoSwitch - The first time an indirect goto is seen we create a
   /// block with the switch for the indirect gotos.  Every time we see the
   /// address of a label taken, we add the label to the indirect goto.  Every
@@ -197,6 +210,7 @@ private:
   /// IndirectGotoSwitch's basic block.
   llvm::SwitchInst *IndirectGotoSwitch;
 
+#endif
   /// LocalDeclMap - This keeps track of the LLVM allocas or globals for local C
   /// decls.
   llvm::DenseMap<const Decl*, llvm::Value*> LocalDeclMap;
@@ -558,7 +572,11 @@ public:
   /// the input field number being accessed.
   static unsigned getAccessedFieldNo(unsigned Idx, const llvm::Constant *Elts);
 
+#ifndef USEINDIRECTBRANCH
   unsigned GetIDForAddrOfLabel(const LabelStmt *L);
+#else
+  llvm::BlockAddress *GetAddrOfLabel(const LabelStmt *L);
+#endif
   llvm::BasicBlock *GetIndirectGotoBlock();
 
   /// EmitMemSetToZero - Generate code to memset a value of the given type to 0.