Add definition of DSBH (Double Swap Bytes within Halfwords) and 
DSHD (Double Swap Halfwords within Doublewords). Add a pattern which replaces
64-bit bswap with a DSBH and DSHD pair.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@147017 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/Mips/MipsISelLowering.cpp b/lib/Target/Mips/MipsISelLowering.cpp
index cfdce3a..d0ee632 100644
--- a/lib/Target/Mips/MipsISelLowering.cpp
+++ b/lib/Target/Mips/MipsISelLowering.cpp
@@ -221,8 +221,10 @@
   if (!Subtarget->hasBitCount())
     setOperationAction(ISD::CTLZ, MVT::i32, Expand);
 
-  if (!Subtarget->hasSwap())
+  if (!Subtarget->hasSwap()) {
     setOperationAction(ISD::BSWAP, MVT::i32, Expand);
+    setOperationAction(ISD::BSWAP, MVT::i64, Expand);
+  }
 
   setTargetDAGCombine(ISD::ADDE);
   setTargetDAGCombine(ISD::SUBE);