[NVPTX] Avoid implicit truncation in getConstant()

Either use getSignedConstant() or change variable type to unsigned
to avoid unnecessary sign extension in the first place.

Author: nikic

llvm/lib/Target/NVPTX/NVPTXISelDAGToDAG.cpp

@@ -3936,8 +3936,8 @@ bool NVPTXDAGToDAGISel::SelectADDRri_imp(
       if (!CN->getAPIntValue().isSignedIntN(32))
         return false;
 
-      Offset = CurDAG->getTargetConstant(CN->getSExtValue(), SDLoc(OpNode),
-                                         MVT::i32);
+      Offset = CurDAG->getSignedTargetConstant(CN->getSExtValue(),
+                                               SDLoc(OpNode), MVT::i32);
       return true;
     }
   }

llvm/lib/Target/NVPTX/NVPTXISelLowering.cpp

@@ -2714,10 +2714,10 @@ SDValue NVPTXTargetLowering::LowerFROUND32(SDValue Op,
 
   // RoundedA = (float) (int) ( A > 0 ? (A + 0.5f) : (A - 0.5f))
   SDValue Bitcast  = DAG.getNode(ISD::BITCAST, SL, MVT::i32, A);
-  const int SignBitMask = 0x80000000;
+  const unsigned SignBitMask = 0x80000000;
   SDValue Sign = DAG.getNode(ISD::AND, SL, MVT::i32, Bitcast,
                              DAG.getConstant(SignBitMask, SL, MVT::i32));
-  const int PointFiveInBits = 0x3F000000;
+  const unsigned PointFiveInBits = 0x3F000000;
   SDValue PointFiveWithSignRaw =
       DAG.getNode(ISD::OR, SL, MVT::i32, Sign,
                   DAG.getConstant(PointFiveInBits, SL, MVT::i32));
@@ -3031,9 +3031,9 @@ SDValue NVPTXTargetLowering::LowerVAARG(SDValue Op, SelectionDAG &DAG) const {
         ISD::ADD, DL, VAList.getValueType(), VAList,
         DAG.getConstant(MA->value() - 1, DL, VAList.getValueType()));
 
-    VAList = DAG.getNode(
-        ISD::AND, DL, VAList.getValueType(), VAList,
-        DAG.getConstant(-(int64_t)MA->value(), DL, VAList.getValueType()));
+    VAList = DAG.getNode(ISD::AND, DL, VAList.getValueType(), VAList,
+                         DAG.getSignedConstant(-(int64_t)MA->value(), DL,
+                                               VAList.getValueType()));
   }
 
   // Increment the pointer, VAList, to the next vaarg