AArch64: Fix cmp;ccmp ordering

[oota-llvm.git] / lib / Target / AArch64 / AArch64ISelLowering.cpp

diff --git a/lib/Target/AArch64/AArch64ISelLowering.cpp b/lib/Target/AArch64/AArch64ISelLowering.cpp
index 3d1235bac0a00ab86c3fb489a8074c8194b92d8b..a4b4d26a0a2d9c7620cd923cb9529163c2bd650d 100644 (file)
--- a/lib/Target/AArch64/AArch64ISelLowering.cpp
+++ b/lib/Target/AArch64/AArch64ISelLowering.cpp
@@ -1374,10 +1374,17 @@ static SDValue emitConjunctionDisjunctionTree(SelectionDAG &DAG, SDValue Val,
     if (!CanPushNegateL && !CanPushNegateR)
       return SDValue();
     // Order the side where we can push the negate through to LHS.
-    if (!CanPushNegateL && CanPushNegateR) {
+    if (!CanPushNegateL && CanPushNegateR)
+      std::swap(LHS, RHS);
+  } else {
+    bool NeedsNegOutL = LHS->getOpcode() == ISD::OR;
+    bool NeedsNegOutR = RHS->getOpcode() == ISD::OR;
+    if (NeedsNegOutL && NeedsNegOutR)
+      return SDValue();
+    // Order the side where we need to negate the output flags to RHS so it
+    // gets emitted first.
+    if (NeedsNegOutL)
       std::swap(LHS, RHS);
-      CanPushNegateL = true;
-    }
   }
 
   // Emit RHS. If we want to negate the tree we only need to push a negate