[NVPTX] Implement isLegalToVectorizeLoadChain

This lets LSV nicely split up underaligned chains.

Differential Revision: https://reviews.llvm.org/D51306

1 files changed, 13 insertions, 0 deletions

diff --git a/llvm/lib/Target/NVPTX/NVPTXTargetTransformInfo.h b/llvm/lib/Target/NVPTX/NVPTXTargetTransformInfo.h
index a631055d36a..14e93f7447d 100644
--- a/llvm/lib/Target/NVPTX/NVPTXTargetTransformInfo.h
+++ b/llvm/lib/Target/NVPTX/NVPTXTargetTransformInfo.h
@@ -49,6 +49,19 @@ public:
     return AddressSpace::ADDRESS_SPACE_GENERIC;
   }
 
+  // Loads and stores can be vectorized if the alignment is at least as big as
+  // the load/store we want to vectorize.
+  bool isLegalToVectorizeLoadChain(unsigned ChainSizeInBytes,
+                                   unsigned Alignment,
+                                   unsigned AddrSpace) const {
+    return Alignment >= ChainSizeInBytes;
+  }
+  bool isLegalToVectorizeStoreChain(unsigned ChainSizeInBytes,
+                                    unsigned Alignment,
+                                    unsigned AddrSpace) const {
+    return isLegalToVectorizeLoadChain(ChainSizeInBytes, Alignment, AddrSpace);
+  }
+
   // NVPTX has infinite registers of all kinds, but the actual machine doesn't.
   // We conservatively return 1 here which is just enough to enable the
   // vectorizers but disables heuristics based on the number of registers.