From a5b2142af19369e646576b3bae7325bae853a42e Mon Sep 17 00:00:00 2001
From: Simon Pilgrim <llvm-dev@redking.me.uk>
Date: Mon, 5 Jan 2015 22:08:48 +0000
Subject: [PATCH] [X86][SSE] lowerVectorShuffleAsByteShift tidyup

Removed local isSequential predicate and use standard helper isSequentialOrUndefInRange instead.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@225216 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/Target/X86/X86ISelLowering.cpp | 35 ++++++++++++------------------
 1 file changed, 14 insertions(+), 21 deletions(-)

diff --git a/lib/Target/X86/X86ISelLowering.cpp b/lib/Target/X86/X86ISelLowering.cpp
index e8e3c5e40fd..e8bac7b9312 100644
--- a/lib/Target/X86/X86ISelLowering.cpp
+++ b/lib/Target/X86/X86ISelLowering.cpp
@@ -3874,7 +3874,7 @@ bool X86TargetLowering::shouldConvertConstantLoadToIntImm(const APInt &Imm,
   return true;
 }
 
-bool X86TargetLowering::isExtractSubvectorCheap(EVT ResVT, 
+bool X86TargetLowering::isExtractSubvectorCheap(EVT ResVT,
                                                 unsigned Index) const {
   if (!isOperationLegalOrCustom(ISD::EXTRACT_SUBVECTOR, ResVT))
     return false;
@@ -6064,7 +6064,7 @@ static SDValue EltsFromConsecutiveLoads(EVT VT, SmallVectorImpl<SDValue> &Elts,
 
     return NewLd;
   }
-  
+
   //TODO: The code below fires only for for loading the low v2i32 / v2f32
   //of a v4i32 / v4f32. It's probably worth generalizing.
   if (NumElems == 4 && LastLoadedElt == 1 && (EltVT.getSizeInBits() == 32) &&
@@ -7051,7 +7051,7 @@ X86TargetLowering::LowerBUILD_VECTOR(SDValue Op, SelectionDAG &DAG) const {
     // Check for a build vector of consecutive loads.
     if (SDValue LD = EltsFromConsecutiveLoads(VT, V, dl, DAG, false))
       return LD;
-    
+
     EVT HVT = EVT::getVectorVT(*DAG.getContext(), ExtVT, NumElems/2);
 
     // Build both the lower and upper subvector.
@@ -7721,17 +7721,6 @@ static SDValue lowerVectorShuffleAsByteShift(SDLoc DL, MVT VT, SDValue V1,
   int Size = Mask.size();
   int Scale = 16 / Size;
 
-  auto isSequential = [](int Base, int StartIndex, int EndIndex, int MaskOffset,
-                         ArrayRef<int> Mask) {
-    for (int i = StartIndex; i < EndIndex; i++) {
-      if (Mask[i] < 0)
-        continue;
-      if (i + Base != Mask[i] - MaskOffset)
-        return false;
-    }
-    return true;
-  };
-
   for (int Shift = 1; Shift < Size; Shift++) {
     int ByteShift = Shift * Scale;
 
@@ -7745,8 +7734,10 @@ static SDValue lowerVectorShuffleAsByteShift(SDLoc DL, MVT VT, SDValue V1,
     }
 
     if (ZeroableRight) {
-      bool ValidShiftRight1 = isSequential(Shift, 0, Size - Shift, 0, Mask);
-      bool ValidShiftRight2 = isSequential(Shift, 0, Size - Shift, Size, Mask);
+      bool ValidShiftRight1 =
+          isSequentialOrUndefInRange(Mask, 0, Size - Shift, Shift);
+      bool ValidShiftRight2 =
+          isSequentialOrUndefInRange(Mask, 0, Size - Shift, Size + Shift);
 
       if (ValidShiftRight1 || ValidShiftRight2) {
         // Cast the inputs to v2i64 to match PSRLDQ.
@@ -7768,8 +7759,10 @@ static SDValue lowerVectorShuffleAsByteShift(SDLoc DL, MVT VT, SDValue V1,
     }
 
     if (ZeroableLeft) {
-      bool ValidShiftLeft1 = isSequential(-Shift, Shift, Size, 0, Mask);
-      bool ValidShiftLeft2 = isSequential(-Shift, Shift, Size, Size, Mask);
+      bool ValidShiftLeft1 =
+          isSequentialOrUndefInRange(Mask, Shift, Size - Shift, 0);
+      bool ValidShiftLeft2 =
+          isSequentialOrUndefInRange(Mask, Shift, Size - Shift, Size);
 
       if (ValidShiftLeft1 || ValidShiftLeft2) {
         // Cast the inputs to v2i64 to match PSLLDQ.
@@ -16843,7 +16836,7 @@ static SDValue getVectorMaskingNode(SDValue Op, SDValue Mask,
 /// The mask is comming as MVT::i8 and it should be truncated
 /// to MVT::i1 while lowering masking intrinsics.
 /// The main difference between ScalarMaskingNode and VectorMaskingNode is using
-/// "X86select" instead of "vselect". We just can't create the "vselect" node for 
+/// "X86select" instead of "vselect". We just can't create the "vselect" node for
 /// a scalar instruction.
 static SDValue getScalarMaskingNode(SDValue Op, SDValue Mask,
                                     SDValue PreservedSrc,
@@ -22777,7 +22770,7 @@ static SDValue PerformEXTRACT_VECTOR_ELTCombine(SDNode *N, SelectionDAG &DAG,
   const TargetLowering &TLI = DAG.getTargetLoweringInfo();
   SDValue Vals[4];
   SDLoc dl(InputVector);
-  
+
   if (TLI.isOperationLegal(ISD::SRA, MVT::i64)) {
     SDValue Cst = DAG.getNode(ISD::BITCAST, dl, MVT::v2i64, InputVector);
     EVT VecIdxTy = DAG.getTargetLoweringInfo().getVectorIdxTy();
@@ -22786,7 +22779,7 @@ static SDValue PerformEXTRACT_VECTOR_ELTCombine(SDNode *N, SelectionDAG &DAG,
     SDValue TopHalf = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, dl, MVT::i64, Cst,
       DAG.getConstant(1, VecIdxTy));
 
-    SDValue ShAmt = DAG.getConstant(32, 
+    SDValue ShAmt = DAG.getConstant(32,
       DAG.getTargetLoweringInfo().getShiftAmountTy(MVT::i64));
     Vals[0] = DAG.getNode(ISD::TRUNCATE, dl, MVT::i32, BottomHalf);
     Vals[1] = DAG.getNode(ISD::TRUNCATE, dl, MVT::i32,