From: Mon P Wang <wangmp@apple.com>
Date: Sat, 14 Mar 2009 00:25:19 +0000 (+0000)
Subject: Avoid doing the transformation c ? 1.0 : 2.0 as load { 2.0, 1.0 } + c*4
X-Git-Tag: android-x86-6.0-r1~1003^2~21770
X-Git-Url: http://git.osdn.net/view?a=commitdiff_plain;h=0b7a786842fd6601b99b1073e5393ebc928c1e6c;p=android-x86%2Fexternal-llvm.git

Avoid doing the transformation c ? 1.0 : 2.0 as load { 2.0, 1.0 } + c*4
if FPConstant is legal because if the FPConstant doesn't need to be stored
in a constant pool, the transformation is unlikely to be profitable.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@66994 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/CodeGen/SelectionDAG/DAGCombiner.cpp b/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
index 7cacbd30212..3e517cfe3a1 100644
--- a/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
+++ b/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
@@ -5654,10 +5654,13 @@ SDValue DAGCombiner::SimplifySelectCC(DebugLoc DL, SDValue N0, SDValue N1,
   // it replaces two constant pool loads with one.  We only do this if the FP
   // type is known to be legal, because if it isn't, then we are before legalize
   // types an we want the other legalization to happen first (e.g. to avoid
-  // messing with soft float).
+  // messing with soft float) and if the ConstantFP is not legal, because if
+  // it is legal, we may not need to store the FP constant in a constant pool.
   if (ConstantFPSDNode *TV = dyn_cast<ConstantFPSDNode>(N2))
     if (ConstantFPSDNode *FV = dyn_cast<ConstantFPSDNode>(N3)) {
       if (TLI.isTypeLegal(N2.getValueType()) &&
+          (TLI.getOperationAction(ISD::ConstantFP, N2.getValueType()) !=
+           TargetLowering::Legal) &&
           // If both constants have multiple uses, then we won't need to do an
           // extra load, they are likely around in registers for other users.
           (TV->hasOneUse() || FV->hasOneUse())) {