Resubmit commit r211533

[oota-llvm.git] / include / llvm / MC / MCValue.h

diff --git a/include/llvm/MC/MCValue.h b/include/llvm/MC/MCValue.h
index 811d331eddacd1c53e67a42e0fa89da0bdd0a1d7..dd86979690cfce5b04b460c9c136f9b44e732865 100644 (file)
--- a/include/llvm/MC/MCValue.h
+++ b/include/llvm/MC/MCValue.h
@@ -14,44 +14,75 @@
 #ifndef LLVM_MC_MCVALUE_H
 #define LLVM_MC_MCVALUE_H
 
+#include "llvm/MC/MCExpr.h"
+#include "llvm/MC/MCSymbol.h"
 #include "llvm/Support/DataTypes.h"
+#include <cassert>
 
 namespace llvm {
-class MCSymbol;
+class MCAsmInfo;
+class raw_ostream;
 
-/// MCValue - This represents an "assembler immediate".  In its most general
-/// form, this can hold "SymbolA - SymbolB + imm64".  Not all targets supports
-/// relocations of this general form, but we need to represent this anyway.
+/// MCValue - This represents an "assembler immediate".  In its most
+/// general form, this can hold ":Kind:(SymbolA - SymbolB + imm64)".
+/// Not all targets supports relocations of this general form, but we
+/// need to represent this anyway.
+///
+/// In general both SymbolA and SymbolB will also have a modifier
+/// analogous to the top-level Kind. Current targets are not expected
+/// to make use of both though. The choice comes down to whether
+/// relocation modifiers apply to the closest symbol or the whole
+/// expression.
+///
+/// In the general form, SymbolB can only be defined if SymbolA is, and both
+/// must be in the same (non-external) section. The latter constraint is not
+/// enforced, since a symbol's section may not be known at construction.
 ///
 /// Note that this class must remain a simple POD value class, because we need
 /// it to live in unions etc.
 class MCValue {
-  MCSymbol *SymA, *SymB;
+  const MCSymbolRefExpr *SymA, *SymB;
   int64_t Cst;
+  uint32_t RefKind;
 public:
 
   int64_t getConstant() const { return Cst; }
-  MCSymbol *getSymA() const { return SymA; }
-  MCSymbol *getSymB() const { return SymB; }
+  const MCSymbolRefExpr *getSymA() const { return SymA; }
+  const MCSymbolRefExpr *getSymB() const { return SymB; }
+  uint32_t getRefKind() const { return RefKind; }
+
+  /// isAbsolute - Is this an absolute (as opposed to relocatable) value.
+  bool isAbsolute() const { return !SymA && !SymB; }
+
+  /// print - Print the value to the stream \p OS.
+  void print(raw_ostream &OS, const MCAsmInfo *MAI) const;
 
-  bool isConstant() const { return !SymA && !SymB; }
-  
-  static MCValue get(MCSymbol *SymA, MCSymbol *SymB = 0, int64_t Val = 0) {
+  /// dump - Print the value to stderr.
+  void dump() const;
+
+  MCSymbolRefExpr::VariantKind getAccessVariant() const;
+
+  static MCValue get(const MCSymbolRefExpr *SymA,
+                     const MCSymbolRefExpr *SymB = nullptr,
+                     int64_t Val = 0, uint32_t RefKind = 0) {
     MCValue R;
+    assert((!SymB || SymA) && "Invalid relocatable MCValue!");
     R.Cst = Val;
     R.SymA = SymA;
     R.SymB = SymB;
+    R.RefKind = RefKind;
     return R;
   }
-  
+
   static MCValue get(int64_t Val) {
     MCValue R;
     R.Cst = Val;
-    R.SymA = 0;
-    R.SymB = 0;
+    R.SymA = nullptr;
+    R.SymB = nullptr;
+    R.RefKind = 0;
     return R;
   }
-  
+
 };
 
 } // end namespace llvm