Introduce new convenience methods for sign extending or
truncating an SDValue (depending on whether the target
type is bigger or smaller than the value's type); or zero
extending or truncating it.  Use it in a few places (this
seems to be a popular operation, but I only modified cases
of it in SelectionDAGBuild).  In particular, the eh_selector
lowering was doing this wrong due to a repeated rather than
inverted test, fixed with this change.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@84027 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/SelectionDAG/SelectionDAG.cpp b/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
index d25a505..542bf64 100644
--- a/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
+++ b/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
@@ -832,6 +832,18 @@
   Root = getEntryNode();
 }
 
+SDValue SelectionDAG::getSExtOrTrunc(SDValue Op, DebugLoc DL, EVT VT) {
+  return VT.bitsGT(Op.getValueType()) ?
+    getNode(ISD::SIGN_EXTEND, DL, VT, Op) :
+    getNode(ISD::TRUNCATE, DL, VT, Op);
+}
+
+SDValue SelectionDAG::getZExtOrTrunc(SDValue Op, DebugLoc DL, EVT VT) {
+  return VT.bitsGT(Op.getValueType()) ?
+    getNode(ISD::ZERO_EXTEND, DL, VT, Op) :
+    getNode(ISD::TRUNCATE, DL, VT, Op);
+}
+
 SDValue SelectionDAG::getZeroExtendInReg(SDValue Op, DebugLoc DL, EVT VT) {
   if (Op.getValueType() == VT) return Op;
   APInt Imm = APInt::getLowBitsSet(Op.getValueSizeInBits(),