From: Craig Topper <craig.topper@intel.com>
Date: Tue, 18 Dec 2018 19:29:08 +0000 (+0000)
Subject: [X86] Don't use SplitOpsAndApply to create ISD::UADDSAT/ISD::USUBSAT nodes. Let type... 
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=401feb8405fd73d271f6c411ff4f2669db8eb722;p=llvm

[X86] Don't use SplitOpsAndApply to create ISD::UADDSAT/ISD::USUBSAT nodes. Let type legalization and op legalization deal with it.

Now that we've switched to target independent nodes we can rely on generic infrastructure to do the legalization for us.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@349526 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/Target/X86/X86ISelLowering.cpp b/lib/Target/X86/X86ISelLowering.cpp
index c316e96f34d..6eb21ab7087 100644
--- a/lib/Target/X86/X86ISelLowering.cpp
+++ b/lib/Target/X86/X86ISelLowering.cpp
@@ -34110,18 +34110,12 @@ static SDValue combineSelect(SDNode *N, SelectionDAG &DAG,
       SDValue OpLHS = Other->getOperand(0), OpRHS = Other->getOperand(1);
       SDValue CondRHS = Cond->getOperand(1);
 
-      auto USUBSATBuilder = [](SelectionDAG &DAG, const SDLoc &DL,
-                               ArrayRef<SDValue> Ops) {
-        return DAG.getNode(ISD::USUBSAT, DL, Ops[0].getValueType(), Ops);
-      };
-
       // Look for a general sub with unsigned saturation first.
       // x >= y ? x-y : 0 --> subus x, y
       // x >  y ? x-y : 0 --> subus x, y
       if ((CC == ISD::SETUGE || CC == ISD::SETUGT) &&
           Other->getOpcode() == ISD::SUB && OpRHS == CondRHS)
-        return SplitOpsAndApply(DAG, Subtarget, DL, VT, { OpLHS, OpRHS },
-                                USUBSATBuilder);
+        return DAG.getNode(ISD::USUBSAT, DL, VT, OpLHS, OpRHS);
 
       if (auto *OpRHSBV = dyn_cast<BuildVectorSDNode>(OpRHS)) {
         if (isa<BuildVectorSDNode>(CondRHS)) {
@@ -34136,8 +34130,7 @@ static SDValue combineSelect(SDNode *N, SelectionDAG &DAG,
               ISD::matchBinaryPredicate(OpRHS, CondRHS, MatchUSUBSAT)) {
             OpRHS = DAG.getNode(ISD::SUB, DL, VT,
                                 DAG.getConstant(0, DL, VT), OpRHS);
-            return SplitOpsAndApply(DAG, Subtarget, DL, VT, { OpLHS, OpRHS },
-                                    USUBSATBuilder);
+            return DAG.getNode(ISD::USUBSAT, DL, VT, OpLHS, OpRHS);
           }
 
           // Another special case: If C was a sign bit, the sub has been
@@ -34149,11 +34142,10 @@ static SDValue combineSelect(SDNode *N, SelectionDAG &DAG,
             if (CC == ISD::SETLT && Other.getOpcode() == ISD::XOR &&
                 ISD::isBuildVectorAllZeros(CondRHS.getNode()) &&
                 OpRHSConst->getAPIntValue().isSignMask()) {
-              OpRHS = DAG.getConstant(OpRHSConst->getAPIntValue(), DL, VT);
               // Note that we have to rebuild the RHS constant here to ensure we
               // don't rely on particular values of undef lanes.
-              return SplitOpsAndApply(DAG, Subtarget, DL, VT, { OpLHS, OpRHS },
-                                      USUBSATBuilder);
+              OpRHS = DAG.getConstant(OpRHSConst->getAPIntValue(), DL, VT);
+              return DAG.getNode(ISD::USUBSAT, DL, VT, OpLHS, OpRHS);
             }
           }
         }
@@ -34186,11 +34178,6 @@ static SDValue combineSelect(SDNode *N, SelectionDAG &DAG,
     if (Other.getNode() && Other.getOpcode() == ISD::ADD) {
       SDValue OpLHS = Other.getOperand(0), OpRHS = Other.getOperand(1);
 
-      auto UADDSATBuilder = [](SelectionDAG &DAG, const SDLoc &DL,
-                               ArrayRef<SDValue> Ops) {
-        return DAG.getNode(ISD::UADDSAT, DL, Ops[0].getValueType(), Ops);
-      };
-
       // Canonicalize condition operands.
       if (CC == ISD::SETUGE) {
         std::swap(CondLHS, CondRHS);
@@ -34202,8 +34189,7 @@ static SDValue combineSelect(SDNode *N, SelectionDAG &DAG,
       // x+y >= x ? x+y : ~0 --> addus x, y
       if (CC == ISD::SETULE && Other == CondRHS &&
           (OpLHS == CondLHS || OpRHS == CondLHS))
-        return SplitOpsAndApply(DAG, Subtarget, DL, VT, { OpLHS, OpRHS },
-                                UADDSATBuilder);
+        return DAG.getNode(ISD::UADDSAT, DL, VT, OpLHS, OpRHS);
 
       if (isa<BuildVectorSDNode>(OpRHS) && isa<BuildVectorSDNode>(CondRHS) &&
           CondLHS == OpLHS) {
@@ -34215,8 +34201,7 @@ static SDValue combineSelect(SDNode *N, SelectionDAG &DAG,
         };
         if (CC == ISD::SETULE &&
             ISD::matchBinaryPredicate(OpRHS, CondRHS, MatchUADDSAT))
-          return SplitOpsAndApply(DAG, Subtarget, DL, VT, { OpLHS, OpRHS },
-                                  UADDSATBuilder);
+          return DAG.getNode(ISD::UADDSAT, DL, VT, OpLHS, OpRHS);
       }
     }
   }
@@ -40660,16 +40645,9 @@ static SDValue combineAddToSUBUS(SDNode *N, SelectionDAG &DAG,
   if (!ISD::matchBinaryPredicate(Op0.getOperand(1), Op1, MatchUSUBSAT))
     return SDValue();
 
-  auto USUBSATBuilder = [](SelectionDAG &DAG, const SDLoc &DL,
-                           ArrayRef<SDValue> Ops) {
-    return DAG.getNode(ISD::USUBSAT, DL, Ops[0].getValueType(), Ops);
-  };
-
-  // Take both operands from the umax node.
   SDLoc DL(N);
-  return SplitOpsAndApply(DAG, Subtarget, DL, VT,
-                          { Op0.getOperand(0), Op0.getOperand(1) },
-                          USUBSATBuilder);
+  return DAG.getNode(ISD::USUBSAT, DL, VT, Op0.getOperand(0),
+                     Op0.getOperand(1));
 }
 
 // Attempt to turn this pattern into PMADDWD.