From 5919b48fe92b8addd0057bac9a4482952271971e Mon Sep 17 00:00:00 2001
From: Chris Lattner <sabre@nondot.org>
Date: Sat, 29 Dec 2007 06:55:23 +0000
Subject: [PATCH] don't fold fp_round(fp_extend(load)) -> fp_round(extload)

llvm-svn: 45400
---
 llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp b/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
index 242fffd18028..0ee455756331 100644
--- a/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
@@ -3672,6 +3672,10 @@ SDOperand DAGCombiner::visitFP_EXTEND(SDNode *N) {
   ConstantFPSDNode *N0CFP = dyn_cast<ConstantFPSDNode>(N0);
   MVT::ValueType VT = N->getValueType(0);
   
+  // If this is fp_round(fpextend), don't fold it, allow ourselves to be folded.
+  if (N->hasOneUse() && (*N->use_begin())->getOpcode() == ISD::FP_ROUND)
+    return SDOperand();
+  
   // fold (fp_extend c1fp) -> c1fp
   if (N0CFP && VT != MVT::ppcf128)
     return DAG.getNode(ISD::FP_EXTEND, VT, N0);
-- 
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