1 files changed, 13 insertions, 0 deletions
diff --git a/llvm/utils/TableGen/CodeGenRegisters.h b/llvm/utils/TableGen/CodeGenRegisters.h
index 72c8ac05025..ab3e68efc24 100644
--- a/llvm/utils/TableGen/CodeGenRegisters.h
+++ b/llvm/utils/TableGen/CodeGenRegisters.h
@@ -101,6 +101,9 @@ namespace llvm {
     // super-class.
     void inheritProperties(CodeGenRegBank&);
 
+    // Map SubRegIndex -> sub-class
+    DenseMap<Record*, CodeGenRegisterClass*> SubClassWithSubReg;
+
   public:
     unsigned EnumValue;
     std::string Namespace;
@@ -145,6 +148,16 @@ namespace llvm {
       return SubClasses.test(RC->EnumValue);
     }
 
+    // getSubClassWithSubReg - Returns the largest sub-class where all
+    // registers have a SubIdx sub-register.
+    CodeGenRegisterClass *getSubClassWithSubReg(Record *SubIdx) const {
+      return SubClassWithSubReg.lookup(SubIdx);
+    }
+
+    void setSubClassWithSubReg(Record *SubIdx, CodeGenRegisterClass *SubRC) {
+      SubClassWithSubReg[SubIdx] = SubRC;
+    }
+
     // getSubClasses - Returns a constant BitVector of subclasses indexed by
     // EnumValue.
     // The SubClasses vector includs an entry for this class.