1 files changed, 22 insertions, 0 deletions
diff --git a/include/llvm/Support/BinaryStreamRef.h b/include/llvm/Support/BinaryStreamRef.h
index e3bd4bf0860e..6d5135cb258d 100644
--- a/include/llvm/Support/BinaryStreamRef.h
+++ b/include/llvm/Support/BinaryStreamRef.h
@@ -166,6 +166,28 @@ public:
                                    ArrayRef<uint8_t> &Buffer) const;
 };
 
+struct BinarySubstreamRef {
+  uint32_t Offset;            // Offset in the parent stream
+  BinaryStreamRef StreamData; // Stream Data
+
+  BinarySubstreamRef slice(uint32_t Off, uint32_t Size) const {
+    BinaryStreamRef SubSub = StreamData.slice(Off, Size);
+    return {Off + Offset, SubSub};
+  }
+  BinarySubstreamRef drop_front(uint32_t N) const {
+    return slice(N, size() - N);
+  }
+  BinarySubstreamRef keep_front(uint32_t N) const { return slice(0, N); }
+
+  std::pair<BinarySubstreamRef, BinarySubstreamRef>
+  split(uint32_t Offset) const {
+    return std::make_pair(keep_front(Offset), drop_front(Offset));
+  }
+
+  uint32_t size() const { return StreamData.getLength(); }
+  bool empty() const { return size() == 0; }
+};
+
 class WritableBinaryStreamRef
     : public BinaryStreamRefBase<WritableBinaryStreamRef,
                                  WritableBinaryStream> {