Implement necessary bits for flt_rounds gcc builtin. 
Codegen bits and llvm-gcc support will follow.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@44182 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/IntrinsicLowering.cpp b/lib/CodeGen/IntrinsicLowering.cpp
index bd3d74d..0d1da86 100644
--- a/lib/CodeGen/IntrinsicLowering.cpp
+++ b/lib/CodeGen/IntrinsicLowering.cpp
@@ -856,6 +856,11 @@
     }
     break;
   }
+  case Intrinsic::flt_rounds:
+     // Lower to "round to the nearest"
+     if (CI->getType() != Type::VoidTy)
+       CI->replaceAllUsesWith(ConstantInt::get(CI->getType(), 1));
+     break;
   }
 
   assert(CI->use_empty() &&
diff --git a/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp b/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp
index 9c0c845..d17fbea 100644
--- a/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp
+++ b/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp
@@ -3677,6 +3677,20 @@
     AddLegalizedOperand(SDOperand(Node, 1), Tmp1);
     return Op.ResNo ? Tmp1 : Result;
   }
+   case ISD::FLT_ROUNDS: {
+    MVT::ValueType VT = Node->getValueType(0);
+    switch (TLI.getOperationAction(Node->getOpcode(), VT)) {
+    default: assert(0 && "This action not supported for this op yet!");
+    case TargetLowering::Custom:
+      Result = TLI.LowerOperation(Op, DAG);
+      if (Result.Val) break;
+      // Fall Thru
+    case TargetLowering::Legal:
+      // If this operation is not supported, lower it to constant 1
+      Result = DAG.getConstant(1, VT);
+      break;
+    }
+  }
   }
   
   assert(Result.getValueType() == Op.getValueType() &&
diff --git a/lib/CodeGen/SelectionDAG/SelectionDAG.cpp b/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
index d92bb9c..38987d9 100644
--- a/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
+++ b/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
@@ -3739,6 +3739,7 @@
   case ISD::SIGN_EXTEND_INREG: return "sign_extend_inreg";
   case ISD::TRUNCATE:    return "truncate";
   case ISD::FP_ROUND:    return "fp_round";
+  case ISD::FLT_ROUNDS:  return "flt_rounds";
   case ISD::FP_ROUND_INREG: return "fp_round_inreg";
   case ISD::FP_EXTEND:   return "fp_extend";
 
diff --git a/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp b/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
index c078f23..ade0a28 100644
--- a/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
+++ b/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
@@ -2930,6 +2930,10 @@
     DAG.setRoot(Tmp.getValue(1));
     return 0;
   }
+  case Intrinsic::flt_rounds: {
+    setValue(&I, DAG.getNode(ISD::FLT_ROUNDS, MVT::i32));
+    return 0;
+  }
   }
 }