Nowadays vectors are only split if they have an even

number of elements.  Make some simplifications based
on this (in particular SplitVecRes_SETCC).  Tighten
up some checking while there.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@75050 91177308-0d34-0410-b5e6-96231b3b80d8

4 files changed, 47 insertions, 59 deletions

diff --git a/lib/CodeGen/SelectionDAG/LegalizeTypes.cpp b/lib/CodeGen/SelectionDAG/LegalizeTypes.cpp
index 3135a44..20caf4a 100644
--- a/lib/CodeGen/SelectionDAG/LegalizeTypes.cpp
+++ b/lib/CodeGen/SelectionDAG/LegalizeTypes.cpp
@@ -732,6 +732,8 @@ void DAGTypeLegalizer::ReplaceValueWith(SDValue From, SDValue To) {
 }
 
 void DAGTypeLegalizer::SetPromotedInteger(SDValue Op, SDValue Result) {
+  assert(Result.getValueType() == TLI.getTypeToTransformTo(Op.getValueType()) &&
+         "Invalid type for promoted integer");
   AnalyzeNewValue(Result);
 
   SDValue &OpEntry = PromotedIntegers[Op];
@@ -740,6 +742,8 @@ void DAGTypeLegalizer::SetPromotedInteger(SDValue Op, SDValue Result) {
 }
 
 void DAGTypeLegalizer::SetSoftenedFloat(SDValue Op, SDValue Result) {
+  assert(Result.getValueType() == TLI.getTypeToTransformTo(Op.getValueType()) &&
+         "Invalid type for softened float");
   AnalyzeNewValue(Result);
 
   SDValue &OpEntry = SoftenedFloats[Op];
@@ -748,6 +752,8 @@ void DAGTypeLegalizer::SetSoftenedFloat(SDValue Op, SDValue Result) {
 }
 
 void DAGTypeLegalizer::SetScalarizedVector(SDValue Op, SDValue Result) {
+  assert(Result.getValueType() == Op.getValueType().getVectorElementType() &&
+         "Invalid type for scalarized vector");
   AnalyzeNewValue(Result);
 
   SDValue &OpEntry = ScalarizedVectors[Op];
@@ -767,6 +773,9 @@ void DAGTypeLegalizer::GetExpandedInteger(SDValue Op, SDValue &Lo,
 
 void DAGTypeLegalizer::SetExpandedInteger(SDValue Op, SDValue Lo,
                                           SDValue Hi) {
+  assert(Lo.getValueType() == TLI.getTypeToTransformTo(Op.getValueType()) &&
+         Hi.getValueType() == Lo.getValueType() &&
+         "Invalid type for expanded integer");
   // Lo/Hi may have been newly allocated, if so, add nodeid's as relevant.
   AnalyzeNewValue(Lo);
   AnalyzeNewValue(Hi);
@@ -790,6 +799,9 @@ void DAGTypeLegalizer::GetExpandedFloat(SDValue Op, SDValue &Lo,
 
 void DAGTypeLegalizer::SetExpandedFloat(SDValue Op, SDValue Lo,
                                         SDValue Hi) {
+  assert(Lo.getValueType() == TLI.getTypeToTransformTo(Op.getValueType()) &&
+         Hi.getValueType() == Lo.getValueType() &&
+         "Invalid type for expanded float");
   // Lo/Hi may have been newly allocated, if so, add nodeid's as relevant.
   AnalyzeNewValue(Lo);
   AnalyzeNewValue(Hi);
@@ -813,6 +825,12 @@ void DAGTypeLegalizer::GetSplitVector(SDValue Op, SDValue &Lo,
 
 void DAGTypeLegalizer::SetSplitVector(SDValue Op, SDValue Lo,
                                       SDValue Hi) {
+  assert(Lo.getValueType().getVectorElementType() ==
+         Op.getValueType().getVectorElementType() &&
+         2*Lo.getValueType().getVectorNumElements() ==
+         Op.getValueType().getVectorNumElements() &&
+         Hi.getValueType() == Lo.getValueType() &&
+         "Invalid type for split vector");
   // Lo/Hi may have been newly allocated, if so, add nodeid's as relevant.
   AnalyzeNewValue(Lo);
   AnalyzeNewValue(Hi);
@@ -825,6 +843,8 @@ void DAGTypeLegalizer::SetSplitVector(SDValue Op, SDValue Lo,
 }
 
 void DAGTypeLegalizer::SetWidenedVector(SDValue Op, SDValue Result) {
+  assert(Result.getValueType() == TLI.getTypeToTransformTo(Op.getValueType()) &&
+         "Invalid type for widened vector");
   AnalyzeNewValue(Result);
 
   SDValue &OpEntry = WidenedVectors[Op];
@@ -901,20 +921,13 @@ bool DAGTypeLegalizer::CustomLowerNode(SDNode *N, MVT VT, bool LegalizeResult) {
 /// GetSplitDestVTs - Compute the VTs needed for the low/hi parts of a type
 /// which is split into two not necessarily identical pieces.
 void DAGTypeLegalizer::GetSplitDestVTs(MVT InVT, MVT &LoVT, MVT &HiVT) {
+  // Currently all types are split in half.
   if (!InVT.isVector()) {
     LoVT = HiVT = TLI.getTypeToTransformTo(InVT);
   } else {
-    MVT NewEltVT = InVT.getVectorElementType();
     unsigned NumElements = InVT.getVectorNumElements();
-    if ((NumElements & (NumElements-1)) == 0) {  // Simple power of two vector.
-      NumElements >>= 1;
-      LoVT = HiVT =  MVT::getVectorVT(NewEltVT, NumElements);
-    } else {                                     // Non-power-of-two vectors.
-      unsigned NewNumElts_Lo = 1 << Log2_32(NumElements);
-      unsigned NewNumElts_Hi = NumElements - NewNumElts_Lo;
-      LoVT = MVT::getVectorVT(NewEltVT, NewNumElts_Lo);
-      HiVT = MVT::getVectorVT(NewEltVT, NewNumElts_Hi);
-    }
+    assert(!(NumElements & 1) && "Splitting vector, but not in half!");
+    LoVT = HiVT = MVT::getVectorVT(InVT.getVectorElementType(), NumElements/2);
   }
 }
 
diff --git a/lib/CodeGen/SelectionDAG/LegalizeTypes.h b/lib/CodeGen/SelectionDAG/LegalizeTypes.h
index 13fc7c5..0dd82c4 100644
--- a/lib/CodeGen/SelectionDAG/LegalizeTypes.h
+++ b/lib/CodeGen/SelectionDAG/LegalizeTypes.h
@@ -64,7 +64,7 @@ private:
     SoftenFloat,     // Convert this float type to a same size integer type.
     ExpandFloat,     // Split this float type into two of half the size.
     ScalarizeVector, // Replace this one-element vector with its element type.
-    SplitVector,     // This vector type should be split into smaller vectors.
+    SplitVector,     // Split this vector type into two of half the size.
     WidenVector      // This vector type should be widened into a larger vector.
   };
 
@@ -533,8 +533,8 @@ private:
   // Vector Splitting Support: LegalizeVectorTypes.cpp
   //===--------------------------------------------------------------------===//
 
-  /// GetSplitVector - Given a processed vector Op which was split into smaller
-  /// vectors, this method returns the smaller vectors.  The first elements of
+  /// GetSplitVector - Given a processed vector Op which was split into vectors
+  /// of half the size, this method returns the halves.  The first elements of
   /// Op coincide with the elements of Lo; the remaining elements of Op coincide
   /// with the elements of Hi: Op is what you would get by concatenating Lo and
   /// Hi.  For example, if Op is a v8i32 that was split into two v4i32's, then
diff --git a/lib/CodeGen/SelectionDAG/LegalizeTypesGeneric.cpp b/lib/CodeGen/SelectionDAG/LegalizeTypesGeneric.cpp
index f947263..0803426 100644
--- a/lib/CodeGen/SelectionDAG/LegalizeTypesGeneric.cpp
+++ b/lib/CodeGen/SelectionDAG/LegalizeTypesGeneric.cpp
@@ -11,9 +11,11 @@
 // The routines here perform legalization when the details of the type (such as
 // whether it is an integer or a float) do not matter.
 // Expansion is the act of changing a computation in an illegal type to be a
-// computation in two identical registers of a smaller type.
+// computation in two identical registers of a smaller type.  The Lo/Hi part
+// is required to be stored first in memory on little/big-endian machines.
 // Splitting is the act of changing a computation in an illegal type to be a
 // computation in two not necessarily identical registers of a smaller type.
+// There are no requirements on how the type is represented in memory.
 //
 //===----------------------------------------------------------------------===//
 
@@ -59,16 +61,12 @@ void DAGTypeLegalizer::ExpandRes_BIT_CONVERT(SDNode *N, SDValue &Lo,
       Hi = DAG.getNode(ISD::BIT_CONVERT, dl, NOutVT, Hi);
       return;
     case SplitVector:
-      // Convert the split parts of the input if it was split in two.
       GetSplitVector(InOp, Lo, Hi);
-      if (Lo.getValueType() == Hi.getValueType()) {
-        if (TLI.isBigEndian())
-          std::swap(Lo, Hi);
-        Lo = DAG.getNode(ISD::BIT_CONVERT, dl, NOutVT, Lo);
-        Hi = DAG.getNode(ISD::BIT_CONVERT, dl, NOutVT, Hi);
-        return;
-      }
-      break;
+      if (TLI.isBigEndian())
+        std::swap(Lo, Hi);
+      Lo = DAG.getNode(ISD::BIT_CONVERT, dl, NOutVT, Lo);
+      Hi = DAG.getNode(ISD::BIT_CONVERT, dl, NOutVT, Hi);
+      return;
     case ScalarizeVector:
       // Convert the element instead.
       SplitInteger(BitConvertToInteger(GetScalarizedVector(InOp)), Lo, Hi);
diff --git a/lib/CodeGen/SelectionDAG/LegalizeVectorTypes.cpp b/lib/CodeGen/SelectionDAG/LegalizeVectorTypes.cpp
index 99eb6b3..535a4c0 100644
--- a/lib/CodeGen/SelectionDAG/LegalizeVectorTypes.cpp
+++ b/lib/CodeGen/SelectionDAG/LegalizeVectorTypes.cpp
@@ -15,8 +15,8 @@
 // eventually decomposes to scalars if the target doesn't support v4f32 or v2f32
 // types.
 // Splitting is the act of changing a computation in an invalid vector type to
-// be a computation in multiple vectors of a smaller type.  For example,
-// implementing <128 x f32> operations in terms of two <64 x f32> operations.
+// be a computation in two vectors of half the size.  For example, implementing
+// <128 x f32> operations in terms of two <64 x f32> operations.
 //
 //===----------------------------------------------------------------------===//
 
@@ -575,7 +575,6 @@ void DAGTypeLegalizer::SplitVecRes_CONVERT_RNDSAT(SDNode *N, SDValue &Lo,
   switch (getTypeAction(InVT)) {
   default: assert(0 && "Unexpected type action!");
   case Legal: {
-    assert(LoVT == HiVT && "Legal non-power-of-two vector type?");
     MVT InNVT = MVT::getVectorVT(InVT.getVectorElementType(),
                                  LoVT.getVectorNumElements());
     VLo = DAG.getNode(ISD::EXTRACT_SUBVECTOR, dl, InNVT, N->getOperand(0),
@@ -591,7 +590,6 @@ void DAGTypeLegalizer::SplitVecRes_CONVERT_RNDSAT(SDNode *N, SDValue &Lo,
     // If the result needs to be split and the input needs to be widened,
     // the two types must have different lengths. Use the widened result
     // and extract from it to do the split.
-    assert(LoVT == HiVT && "Legal non-power-of-two vector type?");
     SDValue InOp = GetWidenedVector(N->getOperand(0));
     MVT InNVT = MVT::getVectorVT(InVT.getVectorElementType(),
                                  LoVT.getVectorNumElements());
@@ -621,9 +619,6 @@ void DAGTypeLegalizer::SplitVecRes_EXTRACT_SUBVECTOR(SDNode *N, SDValue &Lo,
 
   MVT LoVT, HiVT;
   GetSplitDestVTs(N->getValueType(0), LoVT, HiVT);
-  // The indices are not guaranteed to be a multiple of the new vector
-  // size unless the original vector type was split in two.
-  assert(LoVT == HiVT && "Non power-of-two vectors not supported!");
 
   Lo = DAG.getNode(ISD::EXTRACT_SUBVECTOR, dl, LoVT, Vec, Idx);
   Idx = DAG.getNode(ISD::ADD, dl, IdxVT, Idx,
@@ -743,29 +738,17 @@ void DAGTypeLegalizer::SplitVecRes_SETCC(SDNode *N, SDValue &Lo, SDValue &Hi) {
   // Split the input.
   MVT InVT = N->getOperand(0).getValueType();
   SDValue LL, LH, RL, RH;
-  switch (getTypeAction(InVT)) {
-  default: assert(0 && "Unexpected type action!");
-  case WidenVector: assert(0 && "Unimp");
-  case Legal: {
-    assert(LoVT == HiVT && "Legal non-power-of-two vector type?");
-    MVT InNVT = MVT::getVectorVT(InVT.getVectorElementType(),
-                                 LoVT.getVectorNumElements());
-    LL = DAG.getNode(ISD::EXTRACT_SUBVECTOR, DL, InNVT, N->getOperand(0),
-                     DAG.getIntPtrConstant(0));
-    LH = DAG.getNode(ISD::EXTRACT_SUBVECTOR, DL, InNVT, N->getOperand(0),
-                     DAG.getIntPtrConstant(InNVT.getVectorNumElements()));
-
-    RL = DAG.getNode(ISD::EXTRACT_SUBVECTOR, DL, InNVT, N->getOperand(1),
-                     DAG.getIntPtrConstant(0));
-    RH = DAG.getNode(ISD::EXTRACT_SUBVECTOR, DL, InNVT, N->getOperand(1),
-                     DAG.getIntPtrConstant(InNVT.getVectorNumElements()));
-    break;
-  }
-  case SplitVector:
-    GetSplitVector(N->getOperand(0), LL, LH);
-    GetSplitVector(N->getOperand(1), RL, RH);
-    break;
-  }
+  MVT InNVT = MVT::getVectorVT(InVT.getVectorElementType(),
+                               LoVT.getVectorNumElements());
+  LL = DAG.getNode(ISD::EXTRACT_SUBVECTOR, DL, InNVT, N->getOperand(0),
+                   DAG.getIntPtrConstant(0));
+  LH = DAG.getNode(ISD::EXTRACT_SUBVECTOR, DL, InNVT, N->getOperand(0),
+                   DAG.getIntPtrConstant(InNVT.getVectorNumElements()));
+
+  RL = DAG.getNode(ISD::EXTRACT_SUBVECTOR, DL, InNVT, N->getOperand(1),
+                   DAG.getIntPtrConstant(0));
+  RH = DAG.getNode(ISD::EXTRACT_SUBVECTOR, DL, InNVT, N->getOperand(1),
+                   DAG.getIntPtrConstant(InNVT.getVectorNumElements()));
 
   Lo = DAG.getNode(N->getOpcode(), DL, LoVT, LL, RL, N->getOperand(2));
   Hi = DAG.getNode(N->getOpcode(), DL, HiVT, LH, RH, N->getOperand(2));
@@ -783,7 +766,6 @@ void DAGTypeLegalizer::SplitVecRes_UnaryOp(SDNode *N, SDValue &Lo,
   switch (getTypeAction(InVT)) {
   default: assert(0 && "Unexpected type action!");
   case Legal: {
-    assert(LoVT == HiVT && "Legal non-power-of-two vector type?");
     MVT InNVT = MVT::getVectorVT(InVT.getVectorElementType(),
                                  LoVT.getVectorNumElements());
     Lo = DAG.getNode(ISD::EXTRACT_SUBVECTOR, dl, InNVT, N->getOperand(0),
@@ -799,7 +781,6 @@ void DAGTypeLegalizer::SplitVecRes_UnaryOp(SDNode *N, SDValue &Lo,
     // If the result needs to be split and the input needs to be widened,
     // the two types must have different lengths. Use the widened result
     // and extract from it to do the split.
-    assert(LoVT == HiVT && "Legal non-power-of-two vector type?");
     SDValue InOp = GetWidenedVector(N->getOperand(0));
     MVT InNVT = MVT::getVectorVT(InVT.getVectorElementType(),
                                  LoVT.getVectorNumElements());
@@ -824,8 +805,6 @@ void DAGTypeLegalizer::SplitVecRes_VECTOR_SHUFFLE(ShuffleVectorSDNode *N,
   GetSplitVector(N->getOperand(1), Inputs[2], Inputs[3]);
   MVT NewVT = Inputs[0].getValueType();
   unsigned NewElts = NewVT.getVectorNumElements();
-  assert(NewVT == Inputs[1].getValueType() &&
-         "Non power-of-two vectors not supported!");
 
   // If Lo or Hi uses elements from at most two of the four input vectors, then
   // express it as a vector shuffle of those two inputs.  Otherwise extract the
@@ -992,8 +971,6 @@ SDValue DAGTypeLegalizer::SplitVecOp_UnaryOp(SDNode *N) {
   SDValue Lo, Hi;
   DebugLoc dl = N->getDebugLoc();
   GetSplitVector(N->getOperand(0), Lo, Hi);
-  assert(Lo.getValueType() == Hi.getValueType() &&
-         "Returns legal non-power-of-two vector type?");
   MVT InVT = Lo.getValueType();
 
   MVT OutVT = MVT::getVectorVT(ResVT.getVectorElementType(),