Add back r203962, r204028 and r204059.

This reverts commit r204137.

This includes a fix for handling aliases of aliases.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@204178 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 6 insertions, 0 deletions

diff --git a/include/llvm/MC/MCSymbol.h b/include/llvm/MC/MCSymbol.h
index ea14da1e15..866d9a9a68 100644
--- a/include/llvm/MC/MCSymbol.h
+++ b/include/llvm/MC/MCSymbol.h
@@ -18,6 +18,7 @@
 #include "llvm/Support/Compiler.h"
 
 namespace llvm {
+  class MCAsmLayout;
   class MCExpr;
   class MCSection;
   class MCContext;
@@ -145,6 +146,11 @@ namespace llvm {
     // itself.
     const MCSymbol &AliasedSymbol() const;
 
+    // If this symbol is not a variable, return itself. If it is a variable,
+    // evaluate it and check if it is of the form Base + ConstantOffset. If so,
+    // return Base, if not, return nullptr.
+    const MCSymbol *getBaseSymbol(const MCAsmLayout &Layout) const;
+
     void setVariableValue(const MCExpr *Value);
 
     /// @}