Factor common code out of individual if blocks into common tail.

llvm-svn: 168551

1 files changed, 12 insertions, 24 deletions

diff --git a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
index ec75b14..6a1b5dd 100644
--- a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
@@ -4204,6 +4204,7 @@ SelectionDAGBuilder::visitPow(const CallInst &I) {
     IntegerPartOfX = DAG.getNode(ISD::SHL, dl, MVT::i32, IntegerPartOfX,
                                  DAG.getConstant(23, TLI.getPointerTy()));
 
+    SDValue TwoToFractionalPartOfX;
     if (LimitFloatPrecision <= 6) {
       // For floating-point precision of 6:
       //
@@ -4217,14 +4218,8 @@ SelectionDAGBuilder::visitPow(const CallInst &I) {
       SDValue t3 = DAG.getNode(ISD::FADD, dl, MVT::f32, t2,
                                getF32Constant(DAG, 0x3f3c50c8));
       SDValue t4 = DAG.getNode(ISD::FMUL, dl, MVT::f32, t3, X);
-      SDValue t5 = DAG.getNode(ISD::FADD, dl, MVT::f32, t4,
-                               getF32Constant(DAG, 0x3f7f5e7e));
-      SDValue t6 = DAG.getNode(ISD::BITCAST, dl, MVT::i32, t5);
-      SDValue TwoToFractionalPartOfX =
-        DAG.getNode(ISD::ADD, dl, MVT::i32, t6, IntegerPartOfX);
-
-      result = DAG.getNode(ISD::BITCAST, dl,
-                           MVT::f32, TwoToFractionalPartOfX);
+      TwoToFractionalPartOfX = DAG.getNode(ISD::FADD, dl, MVT::f32, t4,
+                                           getF32Constant(DAG, 0x3f7f5e7e));
     } else if (LimitFloatPrecision <= 12) {
       // For floating-point precision of 12:
       //
@@ -4242,14 +4237,8 @@ SelectionDAGBuilder::visitPow(const CallInst &I) {
       SDValue t5 = DAG.getNode(ISD::FADD, dl, MVT::f32, t4,
                                getF32Constant(DAG, 0x3f324b07));
       SDValue t6 = DAG.getNode(ISD::FMUL, dl, MVT::f32, t5, X);
-      SDValue t7 = DAG.getNode(ISD::FADD, dl, MVT::f32, t6,
-                               getF32Constant(DAG, 0x3f7ff8fd));
-      SDValue t8 = DAG.getNode(ISD::BITCAST, dl, MVT::i32, t7);
-      SDValue TwoToFractionalPartOfX =
-        DAG.getNode(ISD::ADD, dl, MVT::i32, t8, IntegerPartOfX);
-
-      result = DAG.getNode(ISD::BITCAST, dl,
-                           MVT::f32, TwoToFractionalPartOfX);
+      TwoToFractionalPartOfX = DAG.getNode(ISD::FADD, dl, MVT::f32, t6,
+                                           getF32Constant(DAG, 0x3f7ff8fd));
     } else { // LimitFloatPrecision <= 18
       // For floating-point precision of 18:
       //
@@ -4278,15 +4267,14 @@ SelectionDAGBuilder::visitPow(const CallInst &I) {
       SDValue t11 = DAG.getNode(ISD::FADD, dl, MVT::f32, t10,
                                 getF32Constant(DAG, 0x3f317234));
       SDValue t12 = DAG.getNode(ISD::FMUL, dl, MVT::f32, t11, X);
-      SDValue t13 = DAG.getNode(ISD::FADD, dl, MVT::f32, t12,
-                                getF32Constant(DAG, 0x3f800000));
-      SDValue t14 = DAG.getNode(ISD::BITCAST, dl, MVT::i32, t13);
-      SDValue TwoToFractionalPartOfX =
-        DAG.getNode(ISD::ADD, dl, MVT::i32, t14, IntegerPartOfX);
-
-      result = DAG.getNode(ISD::BITCAST, dl,
-                           MVT::f32, TwoToFractionalPartOfX);
+      TwoToFractionalPartOfX = DAG.getNode(ISD::FADD, dl, MVT::f32, t12,
+                                           getF32Constant(DAG, 0x3f800000));
     }
+
+    SDValue t13 = DAG.getNode(ISD::BITCAST, dl,MVT::i32,TwoToFractionalPartOfX);
+    result = DAG.getNode(ISD::BITCAST, dl, MVT::f32,
+                         DAG.getNode(ISD::ADD, dl, MVT::i32,
+                                     t13, IntegerPartOfX));
   } else {
     // No special expansion.
     result = DAG.getNode(ISD::FPOW, dl,