1 files changed, 29 insertions, 0 deletions
diff --git a/include/llvm/Target/TargetLowering.h b/include/llvm/Target/TargetLowering.h
index 0130e07c49..1c0ad63ac6 100644
--- a/include/llvm/Target/TargetLowering.h
+++ b/include/llvm/Target/TargetLowering.h
@@ -1183,6 +1183,35 @@ public:
     return false;
   }
 
+  /// Return true if the target supplies and combines to a paired load
+  /// two loaded values of type LoadedType next to each other in memory.
+  /// RequiredAlignment gives the minimal alignment constraints that must be met to
+  /// be able to select this paired load.
+  ///
+  /// This information is *not* used to generate actual paired loads, but it is used
+  /// to generate a sequence of loads that is easier to combine into a paired load.
+  /// For instance, something like this:
+  /// a = load i64* addr
+  /// b = trunc i64 a to i32
+  /// c = lshr i64 a, 32
+  /// d = trunc i64 c to i32
+  /// will be optimized into:
+  /// b = load i32* addr1
+  /// d = load i32* addr2
+  /// Where addr1 = addr2 +/- sizeof(i32).
+  ///
+  /// In other words, unless the target performs a post-isel load combining, this 
+  /// information should not be provided because it will generate more loads.
+  virtual bool hasPairedLoad(Type * /*LoadedType*/,
+                             unsigned & /*RequiredAligment*/) const {
+    return false;
+  }
+
+  virtual bool hasPairedLoad(EVT /*LoadedType*/,
+                             unsigned & /*RequiredAligment*/) const {
+    return false;
+  }
+
   /// Return true if zero-extending the specific node Val to type VT2 is free
   /// (either because it's implicitly zero-extended such as ARM ldrb / ldrh or
   /// because it's folded such as X86 zero-extending loads).