From: Craig Topper <craig.topper@intel.com>
Date: Tue, 28 Nov 2017 22:08:51 +0000 (+0000)
Subject: [X86] Remove code from combineUIntToFP that tried to favor UINT_TO_FP if legal when... 
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=45174c1e734bb35d84b04ef32c4092073663563c;p=llvm

[X86] Remove code from combineUIntToFP that tried to favor UINT_TO_FP if legal when zero extending from vXi8/vX816.

The UINT_TO_FP is immediately converted to SINT_TO_FP when the node is re-evaluated because we'll detect that the sign bit is zero.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@319234 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/Target/X86/X86ISelLowering.cpp b/lib/Target/X86/X86ISelLowering.cpp
index 50e9f643747..9cbe8546ef2 100644
--- a/lib/Target/X86/X86ISelLowering.cpp
+++ b/lib/Target/X86/X86ISelLowering.cpp
@@ -36071,9 +36071,7 @@ static SDValue combineUIntToFP(SDNode *N, SelectionDAG &DAG,
                                  InVT.getVectorNumElements());
     SDValue P = DAG.getNode(ISD::ZERO_EXTEND, dl, DstVT, Op0);
 
-    if (TLI.isOperationLegal(ISD::UINT_TO_FP, DstVT))
-      return DAG.getNode(ISD::UINT_TO_FP, dl, VT, P);
-
+    // UINT_TO_FP isn't legal without AVX512 so use SINT_TO_FP.
     return DAG.getNode(ISD::SINT_TO_FP, dl, VT, P);
   }