X-Git-Url: http://plrg.eecs.uci.edu/git/?a=blobdiff_plain;f=include%2Fllvm%2FMC%2FMCRegisterInfo.h;h=a4d5e0867232025715a9b2f09bde66c44156b25a;hb=6e17bb78bae19a9e2462aa0542eea5d0e3cf7478;hp=e02f35d2cddf0db98d32703f10b53c08f227543e;hpb=84cc6ec88948083632c6aa4db586e8d576be1b31;p=oota-llvm.git

diff --git a/include/llvm/MC/MCRegisterInfo.h b/include/llvm/MC/MCRegisterInfo.h
index e02f35d2cdd..a4d5e086723 100644
--- a/include/llvm/MC/MCRegisterInfo.h
+++ b/include/llvm/MC/MCRegisterInfo.h
@@ -233,6 +233,7 @@ public:
   // These iterators are allowed to sub-class DiffListIterator and access
   // internal list pointers.
   friend class MCSubRegIterator;
+  friend class MCSubRegIndexIterator;
   friend class MCSuperRegIterator;
   friend class MCRegUnitIterator;
   friend class MCRegUnitMaskIterator;
@@ -461,6 +462,38 @@ public:
   }
 };
 
+/// Iterator that enumerates the sub-registers of a Reg and the associated
+/// sub-register indices.
+class MCSubRegIndexIterator {
+  MCSubRegIterator SRIter;
+  const uint16_t *SRIndex;
+public:
+  /// Constructs an iterator that traverses subregisters and their
+  /// associated subregister indices.
+  MCSubRegIndexIterator(unsigned Reg, const MCRegisterInfo *MCRI)
+    : SRIter(Reg, MCRI) {
+    SRIndex = MCRI->SubRegIndices + MCRI->get(Reg).SubRegIndices;
+  }
+
+  /// Returns current sub-register.
+  unsigned getSubReg() const {
+    return *SRIter;
+  }
+  /// Returns sub-register index of the current sub-register.
+  unsigned getSubRegIndex() const {
+    return *SRIndex;
+  }
+
+  /// Returns true if this iterator is not yet at the end.
+  bool isValid() const { return SRIter.isValid(); }
+
+  /// Moves to the next position.
+  void operator++() {
+    ++SRIter;
+    ++SRIndex;
+  }
+};
+
 /// MCSuperRegIterator enumerates all super-registers of Reg.
 /// If IncludeSelf is set, Reg itself is included in the list.
 class MCSuperRegIterator : public MCRegisterInfo::DiffListIterator {
@@ -599,7 +632,7 @@ private:
   unsigned Reg;
   const MCRegisterInfo *MCRI;
   bool IncludeSelf;
-  
+
   MCRegUnitIterator RI;
   MCRegUnitRootIterator RRI;
   MCSuperRegIterator SI;
@@ -619,10 +652,8 @@ public:
     }
   }
 
-  bool isValid() const {
-    return RI.isValid();
-  }
-  
+  bool isValid() const { return RI.isValid(); }
+
   unsigned operator*() const {
     assert (SI.isValid() && "Cannot dereference an invalid iterator.");
     return *SI;