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//===-- LegalizeDAG.cpp - Implement SelectionDAG::Legalize ----------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements the SelectionDAG::Legalize method.
//
//===----------------------------------------------------------------------===//
#include "llvm/CodeGen/SelectionDAG.h"
#include "llvm/CodeGen/MachineFunction.h"
#include "llvm/CodeGen/MachineFrameInfo.h"
#include "llvm/CodeGen/MachineJumpTableInfo.h"
#include "llvm/CodeGen/MachineModuleInfo.h"
#include "llvm/CodeGen/DwarfWriter.h"
#include "llvm/Analysis/DebugInfo.h"
#include "llvm/CodeGen/PseudoSourceValue.h"
#include "llvm/Target/TargetFrameInfo.h"
#include "llvm/Target/TargetLowering.h"
#include "llvm/Target/TargetData.h"
#include "llvm/Target/TargetMachine.h"
#include "llvm/Target/TargetOptions.h"
#include "llvm/Target/TargetSubtarget.h"
#include "llvm/CallingConv.h"
#include "llvm/Constants.h"
#include "llvm/DerivedTypes.h"
#include "llvm/Function.h"
#include "llvm/GlobalVariable.h"
#include "llvm/LLVMContext.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/Compiler.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/MathExtras.h"
#include "llvm/ADT/DenseMap.h"
#include "llvm/ADT/SmallVector.h"
#include "llvm/ADT/SmallPtrSet.h"
#include <map>
using namespace llvm;
//===----------------------------------------------------------------------===//
/// SelectionDAGLegalize - This takes an arbitrary SelectionDAG as input and
/// hacks on it until the target machine can handle it. This involves
/// eliminating value sizes the machine cannot handle (promoting small sizes to
/// large sizes or splitting up large values into small values) as well as
/// eliminating operations the machine cannot handle.
///
/// This code also does a small amount of optimization and recognition of idioms
/// as part of its processing. For example, if a target does not support a
/// 'setcc' instruction efficiently, but does support 'brcc' instruction, this
/// will attempt merge setcc and brc instructions into brcc's.
///
namespace {
class VISIBILITY_HIDDEN SelectionDAGLegalize {
TargetLowering &TLI;
SelectionDAG &DAG;
CodeGenOpt::Level OptLevel;
// Libcall insertion helpers.
/// LastCALLSEQ_END - This keeps track of the CALLSEQ_END node that has been
/// legalized. We use this to ensure that calls are properly serialized
/// against each other, including inserted libcalls.
SDValue LastCALLSEQ_END;
/// IsLegalizingCall - This member is used *only* for purposes of providing
/// helpful assertions that a libcall isn't created while another call is
/// being legalized (which could lead to non-serialized call sequences).
bool IsLegalizingCall;
enum LegalizeAction {
Legal, // The target natively supports this operation.
Promote, // This operation should be executed in a larger type.
Expand // Try to expand this to other ops, otherwise use a libcall.
};
/// ValueTypeActions - This is a bitvector that contains two bits for each
/// value type, where the two bits correspond to the LegalizeAction enum.
/// This can be queried with "getTypeAction(VT)".
TargetLowering::ValueTypeActionImpl ValueTypeActions;
/// LegalizedNodes - For nodes that are of legal width, and that have more
/// than one use, this map indicates what regularized operand to use. This
/// allows us to avoid legalizing the same thing more than once.
DenseMap<SDValue, SDValue> LegalizedNodes;
void AddLegalizedOperand(SDValue From, SDValue To) {
LegalizedNodes.insert(std::make_pair(From, To));
// If someone requests legalization of the new node, return itself.
if (From != To)
LegalizedNodes.insert(std::make_pair(To, To));
}
public:
SelectionDAGLegalize(SelectionDAG &DAG, CodeGenOpt::Level ol);
/// getTypeAction - Return how we should legalize values of this type, either
/// it is already legal or we need to expand it into multiple registers of
/// smaller integer type, or we need to promote it to a larger type.
LegalizeAction getTypeAction(MVT VT) const {
return (LegalizeAction)ValueTypeActions.getTypeAction(VT);
}
/// isTypeLegal - Return true if this type is legal on this target.
///
bool isTypeLegal(MVT VT) const {
return getTypeAction(VT) == Legal;
}
void LegalizeDAG();
private:
/// LegalizeOp - We know that the specified value has a legal type.
/// Recursively ensure that the operands have legal types, then return the
/// result.
SDValue LegalizeOp(SDValue O);
SDValue OptimizeFloatStore(StoreSDNode *ST);
/// PerformInsertVectorEltInMemory - Some target cannot handle a variable
/// insertion index for the INSERT_VECTOR_ELT instruction. In this case, it
/// is necessary to spill the vector being inserted into to memory, perform
/// the insert there, and then read the result back.
SDValue PerformInsertVectorEltInMemory(SDValue Vec, SDValue Val,
SDValue Idx, DebugLoc dl);
SDValue ExpandINSERT_VECTOR_ELT(SDValue Vec, SDValue Val,
SDValue Idx, DebugLoc dl);
/// ShuffleWithNarrowerEltType - Return a vector shuffle operation which
/// performs the same shuffe in terms of order or result bytes, but on a type
/// whose vector element type is narrower than the original shuffle type.
/// e.g. <v4i32> <0, 1, 0, 1> -> v8i16 <0, 1, 2, 3, 0, 1, 2, 3>
SDValue ShuffleWithNarrowerEltType(MVT NVT, MVT VT, DebugLoc dl,
SDValue N1, SDValue N2,
SmallVectorImpl<int> &Mask) const;
bool LegalizeAllNodesNotLeadingTo(SDNode *N, SDNode *Dest,
SmallPtrSet<SDNode*, 32> &NodesLeadingTo);
void LegalizeSetCCCondCode(MVT VT, SDValue &LHS, SDValue &RHS, SDValue &CC,
DebugLoc dl);
SDValue ExpandLibCall(RTLIB::Libcall LC, SDNode *Node, bool isSigned);
SDValue ExpandFPLibCall(SDNode *Node, RTLIB::Libcall Call_F32,
RTLIB::Libcall Call_F64, RTLIB::Libcall Call_F80,
RTLIB::Libcall Call_PPCF128);
SDValue ExpandIntLibCall(SDNode *Node, bool isSigned, RTLIB::Libcall Call_I16,
RTLIB::Libcall Call_I32, RTLIB::Libcall Call_I64,
RTLIB::Libcall Call_I128);
SDValue EmitStackConvert(SDValue SrcOp, MVT SlotVT, MVT DestVT, DebugLoc dl);
SDValue ExpandBUILD_VECTOR(SDNode *Node);
SDValue ExpandSCALAR_TO_VECTOR(SDNode *Node);
SDValue ExpandDBG_STOPPOINT(SDNode *Node);
void ExpandDYNAMIC_STACKALLOC(SDNode *Node,
SmallVectorImpl<SDValue> &Results);
SDValue ExpandFCOPYSIGN(SDNode *Node);
SDValue ExpandLegalINT_TO_FP(bool isSigned, SDValue LegalOp, MVT DestVT,
DebugLoc dl);
SDValue PromoteLegalINT_TO_FP(SDValue LegalOp, MVT DestVT, bool isSigned,
DebugLoc dl);
SDValue PromoteLegalFP_TO_INT(SDValue LegalOp, MVT DestVT, bool isSigned,
DebugLoc dl);
SDValue ExpandBSWAP(SDValue Op, DebugLoc dl);
SDValue ExpandBitCount(unsigned Opc, SDValue Op, DebugLoc dl);
SDValue ExpandExtractFromVectorThroughStack(SDValue Op);
SDValue ExpandVectorBuildThroughStack(SDNode* Node);
void ExpandNode(SDNode *Node, SmallVectorImpl<SDValue> &Results);
void PromoteNode(SDNode *Node, SmallVectorImpl<SDValue> &Results);
};
}
/// ShuffleWithNarrowerEltType - Return a vector shuffle operation which
/// performs the same shuffe in terms of order or result bytes, but on a type
/// whose vector element type is narrower than the original shuffle type.
/// e.g. <v4i32> <0, 1, 0, 1> -> v8i16 <0, 1, 2, 3, 0, 1, 2, 3>
SDValue
SelectionDAGLegalize::ShuffleWithNarrowerEltType(MVT NVT, MVT VT, DebugLoc dl,
SDValue N1, SDValue N2,
SmallVectorImpl<int> &Mask) const {
MVT EltVT = NVT.getVectorElementType();
unsigned NumMaskElts = VT.getVectorNumElements();
unsigned NumDestElts = NVT.getVectorNumElements();
unsigned NumEltsGrowth = NumDestElts / NumMaskElts;
assert(NumEltsGrowth && "Cannot promote to vector type with fewer elts!");
if (NumEltsGrowth == 1)
return DAG.getVectorShuffle(NVT, dl, N1, N2, &Mask[0]);
SmallVector<int, 8> NewMask;
for (unsigned i = 0; i != NumMaskElts; ++i) {
int Idx = Mask[i];
for (unsigned j = 0; j != NumEltsGrowth; ++j) {
if (Idx < 0)
NewMask.push_back(-1);
else
NewMask.push_back(Idx * NumEltsGrowth + j);
}
}
assert(NewMask.size() == NumDestElts && "Non-integer NumEltsGrowth?");
assert(TLI.isShuffleMaskLegal(NewMask, NVT) && "Shuffle not legal?");
return DAG.getVectorShuffle(NVT, dl, N1, N2, &NewMask[0]);
}
SelectionDAGLegalize::SelectionDAGLegalize(SelectionDAG &dag,
CodeGenOpt::Level ol)
: TLI(dag.getTargetLoweringInfo()), DAG(dag), OptLevel(ol),
ValueTypeActions(TLI.getValueTypeActions()) {
assert(MVT::LAST_VALUETYPE <= MVT::MAX_ALLOWED_VALUETYPE &&
"Too many value types for ValueTypeActions to hold!");
}
void SelectionDAGLegalize::LegalizeDAG() {
LastCALLSEQ_END = DAG.getEntryNode();
IsLegalizingCall = false;
// The legalize process is inherently a bottom-up recursive process (users
// legalize their uses before themselves). Given infinite stack space, we
// could just start legalizing on the root and traverse the whole graph. In
// practice however, this causes us to run out of stack space on large basic
// blocks. To avoid this problem, compute an ordering of the nodes where each
// node is only legalized after all of its operands are legalized.
DAG.AssignTopologicalOrder();
for (SelectionDAG::allnodes_iterator I = DAG.allnodes_begin(),
E = prior(DAG.allnodes_end()); I != next(E); ++I)
LegalizeOp(SDValue(I, 0));
// Finally, it's possible the root changed. Get the new root.
SDValue OldRoot = DAG.getRoot();
assert(LegalizedNodes.count(OldRoot) && "Root didn't get legalized?");
DAG.setRoot(LegalizedNodes[OldRoot]);
LegalizedNodes.clear();
// Remove dead nodes now.
DAG.RemoveDeadNodes();
}
/// FindCallEndFromCallStart - Given a chained node that is part of a call
/// sequence, find the CALLSEQ_END node that terminates the call sequence.
static SDNode *FindCallEndFromCallStart(SDNode *Node) {
if (Node->getOpcode() == ISD::CALLSEQ_END)
return Node;
if (Node->use_empty())
return 0; // No CallSeqEnd
// The chain is usually at the end.
SDValue TheChain(Node, Node->getNumValues()-1);
if (TheChain.getValueType() != MVT::Other) {
// Sometimes it's at the beginning.
TheChain = SDValue(Node, 0);
if (TheChain.getValueType() != MVT::Other) {
// Otherwise, hunt for it.
for (unsigned i = 1, e = Node->getNumValues(); i != e; ++i)
if (Node->getValueType(i) == MVT::Other) {
TheChain = SDValue(Node, i);
break;
}
// Otherwise, we walked into a node without a chain.
if (TheChain.getValueType() != MVT::Other)
return 0;
}
}
for (SDNode::use_iterator UI = Node->use_begin(),
E = Node->use_end(); UI != E; ++UI) {
// Make sure to only follow users of our token chain.
SDNode *User = *UI;
for (unsigned i = 0, e = User->getNumOperands(); i != e; ++i)
if (User->getOperand(i) == TheChain)
if (SDNode *Result = FindCallEndFromCallStart(User))
return Result;
}
return 0;
}
/// FindCallStartFromCallEnd - Given a chained node that is part of a call
/// sequence, find the CALLSEQ_START node that initiates the call sequence.
static SDNode *FindCallStartFromCallEnd(SDNode *Node) {
assert(Node && "Didn't find callseq_start for a call??");
if (Node->getOpcode() == ISD::CALLSEQ_START) return Node;
assert(Node->getOperand(0).getValueType() == MVT::Other &&
"Node doesn't have a token chain argument!");
return FindCallStartFromCallEnd(Node->getOperand(0).getNode());
}
/// LegalizeAllNodesNotLeadingTo - Recursively walk the uses of N, looking to
/// see if any uses can reach Dest. If no dest operands can get to dest,
/// legalize them, legalize ourself, and return false, otherwise, return true.
///
/// Keep track of the nodes we fine that actually do lead to Dest in
/// NodesLeadingTo. This avoids retraversing them exponential number of times.
///
bool SelectionDAGLegalize::LegalizeAllNodesNotLeadingTo(SDNode *N, SDNode *Dest,
SmallPtrSet<SDNode*, 32> &NodesLeadingTo) {
if (N == Dest) return true; // N certainly leads to Dest :)
// If we've already processed this node and it does lead to Dest, there is no
// need to reprocess it.
if (NodesLeadingTo.count(N)) return true;
// If the first result of this node has been already legalized, then it cannot
// reach N.
if (LegalizedNodes.count(SDValue(N, 0))) return false;
// Okay, this node has not already been legalized. Check and legalize all
// operands. If none lead to Dest, then we can legalize this node.
bool OperandsLeadToDest = false;
for (unsigned i = 0, e = N->getNumOperands(); i != e; ++i)
OperandsLeadToDest |= // If an operand leads to Dest, so do we.
LegalizeAllNodesNotLeadingTo(N->getOperand(i).getNode(), Dest, NodesLeadingTo);
if (OperandsLeadToDest) {
NodesLeadingTo.insert(N);
return true;
}
// Okay, this node looks safe, legalize it and return false.
LegalizeOp(SDValue(N, 0));
return false;
}
/// ExpandConstantFP - Expands the ConstantFP node to an integer constant or
/// a load from the constant pool.
static SDValue ExpandConstantFP(ConstantFPSDNode *CFP, bool UseCP,
SelectionDAG &DAG, const TargetLowering &TLI) {
bool Extend = false;
DebugLoc dl = CFP->getDebugLoc();
LLVMContext *Context = DAG.getContext();
// If a FP immediate is precise when represented as a float and if the
// target can do an extending load from float to double, we put it into
// the constant pool as a float, even if it's is statically typed as a
// double. This shrinks FP constants and canonicalizes them for targets where
// an FP extending load is the same cost as a normal load (such as on the x87
// fp stack or PPC FP unit).
MVT VT = CFP->getValueType(0);
ConstantFP *LLVMC = const_cast<ConstantFP*>(CFP->getConstantFPValue());
if (!UseCP) {
assert((VT == MVT::f64 || VT == MVT::f32) && "Invalid type expansion");
return DAG.getConstant(LLVMC->getValueAPF().bitcastToAPInt(),
(VT == MVT::f64) ? MVT::i64 : MVT::i32);
}
MVT OrigVT = VT;
MVT SVT = VT;
while (SVT != MVT::f32) {
SVT = (MVT::SimpleValueType)(SVT.getSimpleVT() - 1);
if (CFP->isValueValidForType(SVT, CFP->getValueAPF()) &&
// Only do this if the target has a native EXTLOAD instruction from
// smaller type.
TLI.isLoadExtLegal(ISD::EXTLOAD, SVT) &&
TLI.ShouldShrinkFPConstant(OrigVT)) {
const Type *SType = SVT.getTypeForMVT(*DAG.getContext());
LLVMC = cast<ConstantFP>(Context->getConstantExprFPTrunc(LLVMC, SType));
VT = SVT;
Extend = true;
}
}
SDValue CPIdx = DAG.getConstantPool(LLVMC, TLI.getPointerTy());
unsigned Alignment = cast<ConstantPoolSDNode>(CPIdx)->getAlignment();
if (Extend)
return DAG.getExtLoad(ISD::EXTLOAD, dl,
OrigVT, DAG.getEntryNode(),
CPIdx, PseudoSourceValue::getConstantPool(),
0, VT, false, Alignment);
return DAG.getLoad(OrigVT, dl, DAG.getEntryNode(), CPIdx,
PseudoSourceValue::getConstantPool(), 0, false, Alignment);
}
/// ExpandUnalignedStore - Expands an unaligned store to 2 half-size stores.
static
SDValue ExpandUnalignedStore(StoreSDNode *ST, SelectionDAG &DAG,
const TargetLowering &TLI) {
SDValue Chain = ST->getChain();
SDValue Ptr = ST->getBasePtr();
SDValue Val = ST->getValue();
MVT VT = Val.getValueType();
int Alignment = ST->getAlignment();
int SVOffset = ST->getSrcValueOffset();
DebugLoc dl = ST->getDebugLoc();
if (ST->getMemoryVT().isFloatingPoint() ||
ST->getMemoryVT().isVector()) {
MVT intVT = MVT::getIntegerVT(VT.getSizeInBits());
if (TLI.isTypeLegal(intVT)) {
// Expand to a bitconvert of the value to the integer type of the
// same size, then a (misaligned) int store.
// FIXME: Does not handle truncating floating point stores!
SDValue Result = DAG.getNode(ISD::BIT_CONVERT, dl, intVT, Val);
return DAG.getStore(Chain, dl, Result, Ptr, ST->getSrcValue(),
SVOffset, ST->isVolatile(), Alignment);
} else {
// Do a (aligned) store to a stack slot, then copy from the stack slot
// to the final destination using (unaligned) integer loads and stores.
MVT StoredVT = ST->getMemoryVT();
MVT RegVT =
TLI.getRegisterType(MVT::getIntegerVT(StoredVT.getSizeInBits()));
unsigned StoredBytes = StoredVT.getSizeInBits() / 8;
unsigned RegBytes = RegVT.getSizeInBits() / 8;
unsigned NumRegs = (StoredBytes + RegBytes - 1) / RegBytes;
// Make sure the stack slot is also aligned for the register type.
SDValue StackPtr = DAG.CreateStackTemporary(StoredVT, RegVT);
// Perform the original store, only redirected to the stack slot.
SDValue Store = DAG.getTruncStore(Chain, dl,
Val, StackPtr, NULL, 0, StoredVT);
SDValue Increment = DAG.getConstant(RegBytes, TLI.getPointerTy());
SmallVector<SDValue, 8> Stores;
unsigned Offset = 0;
// Do all but one copies using the full register width.
for (unsigned i = 1; i < NumRegs; i++) {
// Load one integer register's worth from the stack slot.
SDValue Load = DAG.getLoad(RegVT, dl, Store, StackPtr, NULL, 0);
// Store it to the final location. Remember the store.
Stores.push_back(DAG.getStore(Load.getValue(1), dl, Load, Ptr,
ST->getSrcValue(), SVOffset + Offset,
ST->isVolatile(),
MinAlign(ST->getAlignment(), Offset)));
// Increment the pointers.
Offset += RegBytes;
StackPtr = DAG.getNode(ISD::ADD, dl, StackPtr.getValueType(), StackPtr,
Increment);
Ptr = DAG.getNode(ISD::ADD, dl, Ptr.getValueType(), Ptr, Increment);
}
// The last store may be partial. Do a truncating store. On big-endian
// machines this requires an extending load from the stack slot to ensure
// that the bits are in the right place.
MVT MemVT = MVT::getIntegerVT(8 * (StoredBytes - Offset));
// Load from the stack slot.
SDValue Load = DAG.getExtLoad(ISD::EXTLOAD, dl, RegVT, Store, StackPtr,
NULL, 0, MemVT);
Stores.push_back(DAG.getTruncStore(Load.getValue(1), dl, Load, Ptr,
ST->getSrcValue(), SVOffset + Offset,
MemVT, ST->isVolatile(),
MinAlign(ST->getAlignment(), Offset)));
// The order of the stores doesn't matter - say it with a TokenFactor.
return DAG.getNode(ISD::TokenFactor, dl, MVT::Other, &Stores[0],
Stores.size());
}
}
assert(ST->getMemoryVT().isInteger() &&
!ST->getMemoryVT().isVector() &&
"Unaligned store of unknown type.");
// Get the half-size VT
MVT NewStoredVT =
(MVT::SimpleValueType)(ST->getMemoryVT().getSimpleVT() - 1);
int NumBits = NewStoredVT.getSizeInBits();
int IncrementSize = NumBits / 8;
// Divide the stored value in two parts.
SDValue ShiftAmount = DAG.getConstant(NumBits, TLI.getShiftAmountTy());
SDValue Lo = Val;
SDValue Hi = DAG.getNode(ISD::SRL, dl, VT, Val, ShiftAmount);
// Store the two parts
SDValue Store1, Store2;
Store1 = DAG.getTruncStore(Chain, dl, TLI.isLittleEndian()?Lo:Hi, Ptr,
ST->getSrcValue(), SVOffset, NewStoredVT,
ST->isVolatile(), Alignment);
Ptr = DAG.getNode(ISD::ADD, dl, Ptr.getValueType(), Ptr,
DAG.getConstant(IncrementSize, TLI.getPointerTy()));
Alignment = MinAlign(Alignment, IncrementSize);
Store2 = DAG.getTruncStore(Chain, dl, TLI.isLittleEndian()?Hi:Lo, Ptr,
ST->getSrcValue(), SVOffset + IncrementSize,
NewStoredVT, ST->isVolatile(), Alignment);
return DAG.getNode(ISD::TokenFactor, dl, MVT::Other, Store1, Store2);
}
/// ExpandUnalignedLoad - Expands an unaligned load to 2 half-size loads.
static
SDValue ExpandUnalignedLoad(LoadSDNode *LD, SelectionDAG &DAG,
const TargetLowering &TLI) {
int SVOffset = LD->getSrcValueOffset();
SDValue Chain = LD->getChain();
SDValue Ptr = LD->getBasePtr();
MVT VT = LD->getValueType(0);
MVT LoadedVT = LD->getMemoryVT();
DebugLoc dl = LD->getDebugLoc();
if (VT.isFloatingPoint() || VT.isVector()) {
MVT intVT = MVT::getIntegerVT(LoadedVT.getSizeInBits());
if (TLI.isTypeLegal(intVT)) {
// Expand to a (misaligned) integer load of the same size,
// then bitconvert to floating point or vector.
SDValue newLoad = DAG.getLoad(intVT, dl, Chain, Ptr, LD->getSrcValue(),
SVOffset, LD->isVolatile(),
LD->getAlignment());
SDValue Result = DAG.getNode(ISD::BIT_CONVERT, dl, LoadedVT, newLoad);
if (VT.isFloatingPoint() && LoadedVT != VT)
Result = DAG.getNode(ISD::FP_EXTEND, dl, VT, Result);
SDValue Ops[] = { Result, Chain };
return DAG.getMergeValues(Ops, 2, dl);
} else {
// Copy the value to a (aligned) stack slot using (unaligned) integer
// loads and stores, then do a (aligned) load from the stack slot.
MVT RegVT = TLI.getRegisterType(intVT);
unsigned LoadedBytes = LoadedVT.getSizeInBits() / 8;
unsigned RegBytes = RegVT.getSizeInBits() / 8;
unsigned NumRegs = (LoadedBytes + RegBytes - 1) / RegBytes;
// Make sure the stack slot is also aligned for the register type.
SDValue StackBase = DAG.CreateStackTemporary(LoadedVT, RegVT);
SDValue Increment = DAG.getConstant(RegBytes, TLI.getPointerTy());
SmallVector<SDValue, 8> Stores;
SDValue StackPtr = StackBase;
unsigned Offset = 0;
// Do all but one copies using the full register width.
for (unsigned i = 1; i < NumRegs; i++) {
// Load one integer register's worth from the original location.
SDValue Load = DAG.getLoad(RegVT, dl, Chain, Ptr, LD->getSrcValue(),
SVOffset + Offset, LD->isVolatile(),
MinAlign(LD->getAlignment(), Offset));
// Follow the load with a store to the stack slot. Remember the store.
Stores.push_back(DAG.getStore(Load.getValue(1), dl, Load, StackPtr,
NULL, 0));
// Increment the pointers.
Offset += RegBytes;
Ptr = DAG.getNode(ISD::ADD, dl, Ptr.getValueType(), Ptr, Increment);
StackPtr = DAG.getNode(ISD::ADD, dl, StackPtr.getValueType(), StackPtr,
Increment);
}
// The last copy may be partial. Do an extending load.
MVT MemVT = MVT::getIntegerVT(8 * (LoadedBytes - Offset));
SDValue Load = DAG.getExtLoad(ISD::EXTLOAD, dl, RegVT, Chain, Ptr,
LD->getSrcValue(), SVOffset + Offset,
MemVT, LD->isVolatile(),
MinAlign(LD->getAlignment(), Offset));
// Follow the load with a store to the stack slot. Remember the store.
// On big-endian machines this requires a truncating store to ensure
// that the bits end up in the right place.
Stores.push_back(DAG.getTruncStore(Load.getValue(1), dl, Load, StackPtr,
NULL, 0, MemVT));
// The order of the stores doesn't matter - say it with a TokenFactor.
SDValue TF = DAG.getNode(ISD::TokenFactor, dl, MVT::Other, &Stores[0],
Stores.size());
// Finally, perform the original load only redirected to the stack slot.
Load = DAG.getExtLoad(LD->getExtensionType(), dl, VT, TF, StackBase,
NULL, 0, LoadedVT);
// Callers expect a MERGE_VALUES node.
SDValue Ops[] = { Load, TF };
return DAG.getMergeValues(Ops, 2, dl);
}
}
assert(LoadedVT.isInteger() && !LoadedVT.isVector() &&
"Unaligned load of unsupported type.");
// Compute the new VT that is half the size of the old one. This is an
// integer MVT.
unsigned NumBits = LoadedVT.getSizeInBits();
MVT NewLoadedVT;
NewLoadedVT = MVT::getIntegerVT(NumBits/2);
NumBits >>= 1;
unsigned Alignment = LD->getAlignment();
unsigned IncrementSize = NumBits / 8;
ISD::LoadExtType HiExtType = LD->getExtensionType();
// If the original load is NON_EXTLOAD, the hi part load must be ZEXTLOAD.
if (HiExtType == ISD::NON_EXTLOAD)
HiExtType = ISD::ZEXTLOAD;
// Load the value in two parts
SDValue Lo, Hi;
if (TLI.isLittleEndian()) {
Lo = DAG.getExtLoad(ISD::ZEXTLOAD, dl, VT, Chain, Ptr, LD->getSrcValue(),
SVOffset, NewLoadedVT, LD->isVolatile(), Alignment);
Ptr = DAG.getNode(ISD::ADD, dl, Ptr.getValueType(), Ptr,
DAG.getConstant(IncrementSize, TLI.getPointerTy()));
Hi = DAG.getExtLoad(HiExtType, dl, VT, Chain, Ptr, LD->getSrcValue(),
SVOffset + IncrementSize, NewLoadedVT, LD->isVolatile(),
MinAlign(Alignment, IncrementSize));
} else {
Hi = DAG.getExtLoad(HiExtType, dl, VT, Chain, Ptr, LD->getSrcValue(),
SVOffset, NewLoadedVT, LD->isVolatile(), Alignment);
Ptr = DAG.getNode(ISD::ADD, dl, Ptr.getValueType(), Ptr,
DAG.getConstant(IncrementSize, TLI.getPointerTy()));
Lo = DAG.getExtLoad(ISD::ZEXTLOAD, dl, VT, Chain, Ptr, LD->getSrcValue(),
SVOffset + IncrementSize, NewLoadedVT, LD->isVolatile(),
MinAlign(Alignment, IncrementSize));
}
// aggregate the two parts
SDValue ShiftAmount = DAG.getConstant(NumBits, TLI.getShiftAmountTy());
SDValue Result = DAG.getNode(ISD::SHL, dl, VT, Hi, ShiftAmount);
Result = DAG.getNode(ISD::OR, dl, VT, Result, Lo);
SDValue TF = DAG.getNode(ISD::TokenFactor, dl, MVT::Other, Lo.getValue(1),
Hi.getValue(1));
SDValue Ops[] = { Result, TF };
return DAG.getMergeValues(Ops, 2, dl);
}
/// PerformInsertVectorEltInMemory - Some target cannot handle a variable
/// insertion index for the INSERT_VECTOR_ELT instruction. In this case, it
/// is necessary to spill the vector being inserted into to memory, perform
/// the insert there, and then read the result back.
SDValue SelectionDAGLegalize::
PerformInsertVectorEltInMemory(SDValue Vec, SDValue Val, SDValue Idx,
DebugLoc dl) {
SDValue Tmp1 = Vec;
SDValue Tmp2 = Val;
SDValue Tmp3 = Idx;
// If the target doesn't support this, we have to spill the input vector
// to a temporary stack slot, update the element, then reload it. This is
// badness. We could also load the value into a vector register (either
// with a "move to register" or "extload into register" instruction, then
// permute it into place, if the idx is a constant and if the idx is
// supported by the target.
MVT VT = Tmp1.getValueType();
MVT EltVT = VT.getVectorElementType();
MVT IdxVT = Tmp3.getValueType();
MVT PtrVT = TLI.getPointerTy();
SDValue StackPtr = DAG.CreateStackTemporary(VT);
int SPFI = cast<FrameIndexSDNode>(StackPtr.getNode())->getIndex();
// Store the vector.
SDValue Ch = DAG.getStore(DAG.getEntryNode(), dl, Tmp1, StackPtr,
PseudoSourceValue::getFixedStack(SPFI), 0);
// Truncate or zero extend offset to target pointer type.
unsigned CastOpc = IdxVT.bitsGT(PtrVT) ? ISD::TRUNCATE : ISD::ZERO_EXTEND;
Tmp3 = DAG.getNode(CastOpc, dl, PtrVT, Tmp3);
// Add the offset to the index.
unsigned EltSize = EltVT.getSizeInBits()/8;
Tmp3 = DAG.getNode(ISD::MUL, dl, IdxVT, Tmp3,DAG.getConstant(EltSize, IdxVT));
SDValue StackPtr2 = DAG.getNode(ISD::ADD, dl, IdxVT, Tmp3, StackPtr);
// Store the scalar value.
Ch = DAG.getTruncStore(Ch, dl, Tmp2, StackPtr2,
PseudoSourceValue::getFixedStack(SPFI), 0, EltVT);
// Load the updated vector.
return DAG.getLoad(VT, dl, Ch, StackPtr,
PseudoSourceValue::getFixedStack(SPFI), 0);
}
SDValue SelectionDAGLegalize::
ExpandINSERT_VECTOR_ELT(SDValue Vec, SDValue Val, SDValue Idx, DebugLoc dl) {
if (ConstantSDNode *InsertPos = dyn_cast<ConstantSDNode>(Idx)) {
// SCALAR_TO_VECTOR requires that the type of the value being inserted
// match the element type of the vector being created, except for
// integers in which case the inserted value can be over width.
MVT EltVT = Vec.getValueType().getVectorElementType();
if (Val.getValueType() == EltVT ||
(EltVT.isInteger() && Val.getValueType().bitsGE(EltVT))) {
SDValue ScVec = DAG.getNode(ISD::SCALAR_TO_VECTOR, dl,
Vec.getValueType(), Val);
unsigned NumElts = Vec.getValueType().getVectorNumElements();
// We generate a shuffle of InVec and ScVec, so the shuffle mask
// should be 0,1,2,3,4,5... with the appropriate element replaced with
// elt 0 of the RHS.
SmallVector<int, 8> ShufOps;
for (unsigned i = 0; i != NumElts; ++i)
ShufOps.push_back(i != InsertPos->getZExtValue() ? i : NumElts);
return DAG.getVectorShuffle(Vec.getValueType(), dl, Vec, ScVec,
&ShufOps[0]);
}
}
return PerformInsertVectorEltInMemory(Vec, Val, Idx, dl);
}
SDValue SelectionDAGLegalize::OptimizeFloatStore(StoreSDNode* ST) {
// Turn 'store float 1.0, Ptr' -> 'store int 0x12345678, Ptr'
// FIXME: We shouldn't do this for TargetConstantFP's.
// FIXME: move this to the DAG Combiner! Note that we can't regress due
// to phase ordering between legalized code and the dag combiner. This
// probably means that we need to integrate dag combiner and legalizer
// together.
// We generally can't do this one for long doubles.
SDValue Tmp1 = ST->getChain();
SDValue Tmp2 = ST->getBasePtr();
SDValue Tmp3;
int SVOffset = ST->getSrcValueOffset();
unsigned Alignment = ST->getAlignment();
bool isVolatile = ST->isVolatile();
DebugLoc dl = ST->getDebugLoc();
if (ConstantFPSDNode *CFP = dyn_cast<ConstantFPSDNode>(ST->getValue())) {
if (CFP->getValueType(0) == MVT::f32 &&
getTypeAction(MVT::i32) == Legal) {
Tmp3 = DAG.getConstant(CFP->getValueAPF().
bitcastToAPInt().zextOrTrunc(32),
MVT::i32);
return DAG.getStore(Tmp1, dl, Tmp3, Tmp2, ST->getSrcValue(),
SVOffset, isVolatile, Alignment);
} else if (CFP->getValueType(0) == MVT::f64) {
// If this target supports 64-bit registers, do a single 64-bit store.
if (getTypeAction(MVT::i64) == Legal) {
Tmp3 = DAG.getConstant(CFP->getValueAPF().bitcastToAPInt().
zextOrTrunc(64), MVT::i64);
return DAG.getStore(Tmp1, dl, Tmp3, Tmp2, ST->getSrcValue(),
SVOffset, isVolatile, Alignment);
} else if (getTypeAction(MVT::i32) == Legal && !ST->isVolatile()) {
// Otherwise, if the target supports 32-bit registers, use 2 32-bit
// stores. If the target supports neither 32- nor 64-bits, this
// xform is certainly not worth it.
const APInt &IntVal =CFP->getValueAPF().bitcastToAPInt();
SDValue Lo = DAG.getConstant(APInt(IntVal).trunc(32), MVT::i32);
SDValue Hi = DAG.getConstant(IntVal.lshr(32).trunc(32), MVT::i32);
if (TLI.isBigEndian()) std::swap(Lo, Hi);
Lo = DAG.getStore(Tmp1, dl, Lo, Tmp2, ST->getSrcValue(),
SVOffset, isVolatile, Alignment);
Tmp2 = DAG.getNode(ISD::ADD, dl, Tmp2.getValueType(), Tmp2,
DAG.getIntPtrConstant(4));
Hi = DAG.getStore(Tmp1, dl, Hi, Tmp2, ST->getSrcValue(), SVOffset+4,
isVolatile, MinAlign(Alignment, 4U));
return DAG.getNode(ISD::TokenFactor, dl, MVT::Other, Lo, Hi);
}
}
}
return SDValue();
}
/// LegalizeOp - We know that the specified value has a legal type, and
/// that its operands are legal. Now ensure that the operation itself
/// is legal, recursively ensuring that the operands' operations remain
/// legal.
SDValue SelectionDAGLegalize::LegalizeOp(SDValue Op) {
if (Op.getOpcode() == ISD::TargetConstant) // Allow illegal target nodes.
return Op;
SDNode *Node = Op.getNode();
DebugLoc dl = Node->getDebugLoc();
for (unsigned i = 0, e = Node->getNumValues(); i != e; ++i)
assert(getTypeAction(Node->getValueType(i)) == Legal &&
"Unexpected illegal type!");
for (unsigned i = 0, e = Node->getNumOperands(); i != e; ++i)
assert((isTypeLegal(Node->getOperand(i).getValueType()) ||
Node->getOperand(i).getOpcode() == ISD::TargetConstant) &&
"Unexpected illegal type!");
// Note that LegalizeOp may be reentered even from single-use nodes, which
// means that we always must cache transformed nodes.
DenseMap<SDValue, SDValue>::iterator I = LegalizedNodes.find(Op);
if (I != LegalizedNodes.end()) return I->second;
SDValue Tmp1, Tmp2, Tmp3, Tmp4;
SDValue Result = Op;
bool isCustom = false;
// Figure out the correct action; the way to query this varies by opcode
TargetLowering::LegalizeAction Action;
bool SimpleFinishLegalizing = true;
switch (Node->getOpcode()) {
case ISD::INTRINSIC_W_CHAIN:
case ISD::INTRINSIC_WO_CHAIN:
case ISD::INTRINSIC_VOID:
case ISD::VAARG:
case ISD::STACKSAVE:
Action = TLI.getOperationAction(Node->getOpcode(), MVT::Other);
break;
case ISD::SINT_TO_FP:
case ISD::UINT_TO_FP:
case ISD::EXTRACT_VECTOR_ELT:
Action = TLI.getOperationAction(Node->getOpcode(),
Node->getOperand(0).getValueType());
break;
case ISD::FP_ROUND_INREG:
case ISD::SIGN_EXTEND_INREG: {
MVT InnerType = cast<VTSDNode>(Node->getOperand(1))->getVT();
Action = TLI.getOperationAction(Node->getOpcode(), InnerType);
break;
}
case ISD::SELECT_CC:
case ISD::SETCC:
case ISD::BR_CC: {
unsigned CCOperand = Node->getOpcode() == ISD::SELECT_CC ? 4 :
Node->getOpcode() == ISD::SETCC ? 2 : 1;
unsigned CompareOperand = Node->getOpcode() == ISD::BR_CC ? 2 : 0;
MVT OpVT = Node->getOperand(CompareOperand).getValueType();
ISD::CondCode CCCode =
cast<CondCodeSDNode>(Node->getOperand(CCOperand))->get();
Action = TLI.getCondCodeAction(CCCode, OpVT);
if (Action == TargetLowering::Legal) {
if (Node->getOpcode() == ISD::SELECT_CC)
Action = TLI.getOperationAction(Node->getOpcode(),
Node->getValueType(0));
else
Action = TLI.getOperationAction(Node->getOpcode(), OpVT);
}
break;
}
case ISD::LOAD:
case ISD::STORE:
// FIXME: Model these properly. LOAD and STORE are complicated, and
// STORE expects the unlegalized operand in some cases.
SimpleFinishLegalizing = false;
break;
case ISD::CALLSEQ_START:
case ISD::CALLSEQ_END:
// FIXME: This shouldn't be necessary. These nodes have special properties
// dealing with the recursive nature of legalization. Removing this
// special case should be done as part of making LegalizeDAG non-recursive.
SimpleFinishLegalizing = false;
break;
case ISD::CALL:
// FIXME: Legalization for calls requires custom-lowering the call before
// legalizing the operands! (I haven't looked into precisely why.)
SimpleFinishLegalizing = false;
break;
case ISD::EXTRACT_ELEMENT:
case ISD::FLT_ROUNDS_:
case ISD::SADDO:
case ISD::SSUBO:
case ISD::UADDO:
case ISD::USUBO:
case ISD::SMULO:
case ISD::UMULO:
case ISD::FPOWI:
case ISD::MERGE_VALUES:
case ISD::EH_RETURN:
case ISD::FRAME_TO_ARGS_OFFSET:
// These operations lie about being legal: when they claim to be legal,
// they should actually be expanded.
Action = TLI.getOperationAction(Node->getOpcode(), Node->getValueType(0));
if (Action == TargetLowering::Legal)
Action = TargetLowering::Expand;
break;
case ISD::TRAMPOLINE:
case ISD::FRAMEADDR:
case ISD::RETURNADDR:
case ISD::FORMAL_ARGUMENTS:
// These operations lie about being legal: when they claim to be legal,
// they should actually be custom-lowered.
Action = TLI.getOperationAction(Node->getOpcode(), Node->getValueType(0));
if (Action == TargetLowering::Legal)
Action = TargetLowering::Custom;
break;
case ISD::BUILD_VECTOR:
// A weird case: legalization for BUILD_VECTOR never legalizes the
// operands!
// FIXME: This really sucks... changing it isn't semantically incorrect,
// but it massively pessimizes the code for floating-point BUILD_VECTORs
// because ConstantFP operands get legalized into constant pool loads
// before the BUILD_VECTOR code can see them. It doesn't usually bite,
// though, because BUILD_VECTORS usually get lowered into other nodes
// which get legalized properly.
SimpleFinishLegalizing = false;
break;
default:
if (Node->getOpcode() >= ISD::BUILTIN_OP_END) {
Action = TargetLowering::Legal;
} else {
Action = TLI.getOperationAction(Node->getOpcode(), Node->getValueType(0));
}
break;
}
if (SimpleFinishLegalizing) {
SmallVector<SDValue, 8> Ops, ResultVals;
for (unsigned i = 0, e = Node->getNumOperands(); i != e; ++i)
Ops.push_back(LegalizeOp(Node->getOperand(i)));
switch (Node->getOpcode()) {
default: break;
case ISD::BR:
case ISD::BRIND:
case ISD::BR_JT:
case ISD::BR_CC:
case ISD::BRCOND:
case ISD::RET:
// Branches tweak the chain to include LastCALLSEQ_END
Ops[0] = DAG.getNode(ISD::TokenFactor, dl, MVT::Other, Ops[0],
LastCALLSEQ_END);
Ops[0] = LegalizeOp(Ops[0]);
LastCALLSEQ_END = DAG.getEntryNode();
break;
case ISD::SHL:
case ISD::SRL:
case ISD::SRA:
case ISD::ROTL:
case ISD::ROTR:
// Legalizing shifts/rotates requires adjusting the shift amount
// to the appropriate width.
if (!Ops[1].getValueType().isVector())
Ops[1] = LegalizeOp(DAG.getShiftAmountOperand(Ops[1]));
break;
}
Result = DAG.UpdateNodeOperands(Result.getValue(0), Ops.data(),
Ops.size());
switch (Action) {
case TargetLowering::Legal:
for (unsigned i = 0, e = Node->getNumValues(); i != e; ++i)
ResultVals.push_back(Result.getValue(i));
break;
case TargetLowering::Custom:
// FIXME: The handling for custom lowering with multiple results is
// a complete mess.
Tmp1 = TLI.LowerOperation(Result, DAG);
if (Tmp1.getNode()) {
for (unsigned i = 0, e = Node->getNumValues(); i != e; ++i) {
if (e == 1)
ResultVals.push_back(Tmp1);
else
ResultVals.push_back(Tmp1.getValue(i));
}
break;
}
// FALL THROUGH
case TargetLowering::Expand:
ExpandNode(Result.getNode(), ResultVals);
break;
case TargetLowering::Promote:
PromoteNode(Result.getNode(), ResultVals);
break;
}
if (!ResultVals.empty()) {
for (unsigned i = 0, e = ResultVals.size(); i != e; ++i) {
if (ResultVals[i] != SDValue(Node, i))
ResultVals[i] = LegalizeOp(ResultVals[i]);
AddLegalizedOperand(SDValue(Node, i), ResultVals[i]);
}
return ResultVals[Op.getResNo()];
}
}
switch (Node->getOpcode()) {
default:
#ifndef NDEBUG
cerr << "NODE: "; Node->dump(&DAG); cerr << "\n";
#endif
llvm_unreachable("Do not know how to legalize this operator!");
case ISD::CALL:
// The only option for this is to custom lower it.
Tmp3 = TLI.LowerOperation(Result.getValue(0), DAG);
assert(Tmp3.getNode() && "Target didn't custom lower this node!");
// A call within a calling sequence must be legalized to something
// other than the normal CALLSEQ_END. Violating this gets Legalize
// into an infinite loop.
assert ((!IsLegalizingCall ||
Node->getOpcode() != ISD::CALL ||
Tmp3.getNode()->getOpcode() != ISD::CALLSEQ_END) &&
"Nested CALLSEQ_START..CALLSEQ_END not supported.");
// The number of incoming and outgoing values should match; unless the final
// outgoing value is a flag.
assert((Tmp3.getNode()->getNumValues() == Result.getNode()->getNumValues() ||
(Tmp3.getNode()->getNumValues() == Result.getNode()->getNumValues() + 1 &&
Tmp3.getNode()->getValueType(Tmp3.getNode()->getNumValues() - 1) ==
MVT::Flag)) &&
"Lowering call/formal_arguments produced unexpected # results!");
// Since CALL/FORMAL_ARGUMENTS nodes produce multiple values, make sure to
// remember that we legalized all of them, so it doesn't get relegalized.
for (unsigned i = 0, e = Tmp3.getNode()->getNumValues(); i != e; ++i) {
if (Tmp3.getNode()->getValueType(i) == MVT::Flag)
continue;
Tmp1 = LegalizeOp(Tmp3.getValue(i));
if (Op.getResNo() == i)
Tmp2 = Tmp1;
AddLegalizedOperand(SDValue(Node, i), Tmp1);
}
return Tmp2;
case ISD::BUILD_VECTOR:
switch (TLI.getOperationAction(ISD::BUILD_VECTOR, Node->getValueType(0))) {
default: llvm_unreachable("This action is not supported yet!");
case TargetLowering::Custom:
Tmp3 = TLI.LowerOperation(Result, DAG);
if (Tmp3.getNode()) {
Result = Tmp3;
break;
}
// FALLTHROUGH
case TargetLowering::Expand:
Result = ExpandBUILD_VECTOR(Result.getNode());
break;
}
break;
case ISD::CALLSEQ_START: {
SDNode *CallEnd = FindCallEndFromCallStart(Node);
// Recursively Legalize all of the inputs of the call end that do not lead
// to this call start. This ensures that any libcalls that need be inserted
// are inserted *before* the CALLSEQ_START.
{SmallPtrSet<SDNode*, 32> NodesLeadingTo;
for (unsigned i = 0, e = CallEnd->getNumOperands(); i != e; ++i)
LegalizeAllNodesNotLeadingTo(CallEnd->getOperand(i).getNode(), Node,
NodesLeadingTo);
}
// Now that we legalized all of the inputs (which may have inserted
// libcalls) create the new CALLSEQ_START node.
Tmp1 = LegalizeOp(Node->getOperand(0)); // Legalize the chain.
// Merge in the last call, to ensure that this call start after the last
// call ended.
if (LastCALLSEQ_END.getOpcode() != ISD::EntryToken) {
Tmp1 = DAG.getNode(ISD::TokenFactor, dl, MVT::Other,
Tmp1, LastCALLSEQ_END);
Tmp1 = LegalizeOp(Tmp1);
}
// Do not try to legalize the target-specific arguments (#1+).
if (Tmp1 != Node->getOperand(0)) {
SmallVector<SDValue, 8> Ops(Node->op_begin(), Node->op_end());
Ops[0] = Tmp1;
Result = DAG.UpdateNodeOperands(Result, &Ops[0], Ops.size());
}
// Remember that the CALLSEQ_START is legalized.
AddLegalizedOperand(Op.getValue(0), Result);
if (Node->getNumValues() == 2) // If this has a flag result, remember it.
AddLegalizedOperand(Op.getValue(1), Result.getValue(1));
// Now that the callseq_start and all of the non-call nodes above this call
// sequence have been legalized, legalize the call itself. During this
// process, no libcalls can/will be inserted, guaranteeing that no calls
// can overlap.
assert(!IsLegalizingCall && "Inconsistent sequentialization of calls!");
// Note that we are selecting this call!
LastCALLSEQ_END = SDValue(CallEnd, 0);
IsLegalizingCall = true;
// Legalize the call, starting from the CALLSEQ_END.
LegalizeOp(LastCALLSEQ_END);
assert(!IsLegalizingCall && "CALLSEQ_END should have cleared this!");
return Result;
}
case ISD::CALLSEQ_END:
// If the CALLSEQ_START node hasn't been legalized first, legalize it. This
// will cause this node to be legalized as well as handling libcalls right.
if (LastCALLSEQ_END.getNode() != Node) {
LegalizeOp(SDValue(FindCallStartFromCallEnd(Node), 0));
DenseMap<SDValue, SDValue>::iterator I = LegalizedNodes.find(Op);
assert(I != LegalizedNodes.end() &&
"Legalizing the call start should have legalized this node!");
return I->second;
}
// Otherwise, the call start has been legalized and everything is going
// according to plan. Just legalize ourselves normally here.
Tmp1 = LegalizeOp(Node->getOperand(0)); // Legalize the chain.
// Do not try to legalize the target-specific arguments (#1+), except for
// an optional flag input.
if (Node->getOperand(Node->getNumOperands()-1).getValueType() != MVT::Flag){
if (Tmp1 != Node->getOperand(0)) {
SmallVector<SDValue, 8> Ops(Node->op_begin(), Node->op_end());
Ops[0] = Tmp1;
Result = DAG.UpdateNodeOperands(Result, &Ops[0], Ops.size());
}
} else {
Tmp2 = LegalizeOp(Node->getOperand(Node->getNumOperands()-1));
if (Tmp1 != Node->getOperand(0) ||
Tmp2 != Node->getOperand(Node->getNumOperands()-1)) {
SmallVector<SDValue, 8> Ops(Node->op_begin(), Node->op_end());
Ops[0] = Tmp1;
Ops.back() = Tmp2;
Result = DAG.UpdateNodeOperands(Result, &Ops[0], Ops.size());
}
}
assert(IsLegalizingCall && "Call sequence imbalance between start/end?");
// This finishes up call legalization.
IsLegalizingCall = false;
// If the CALLSEQ_END node has a flag, remember that we legalized it.
AddLegalizedOperand(SDValue(Node, 0), Result.getValue(0));
if (Node->getNumValues() == 2)
AddLegalizedOperand(SDValue(Node, 1), Result.getValue(1));
return Result.getValue(Op.getResNo());
case ISD::LOAD: {
LoadSDNode *LD = cast<LoadSDNode>(Node);
Tmp1 = LegalizeOp(LD->getChain()); // Legalize the chain.
Tmp2 = LegalizeOp(LD->getBasePtr()); // Legalize the base pointer.
ISD::LoadExtType ExtType = LD->getExtensionType();
if (ExtType == ISD::NON_EXTLOAD) {
MVT VT = Node->getValueType(0);
Result = DAG.UpdateNodeOperands(Result, Tmp1, Tmp2, LD->getOffset());
Tmp3 = Result.getValue(0);
Tmp4 = Result.getValue(1);
switch (TLI.getOperationAction(Node->getOpcode(), VT)) {
default: llvm_unreachable("This action is not supported yet!");
case TargetLowering::Legal:
// If this is an unaligned load and the target doesn't support it,
// expand it.
if (!TLI.allowsUnalignedMemoryAccesses()) {
unsigned ABIAlignment = TLI.getTargetData()->
getABITypeAlignment(LD->getMemoryVT().getTypeForMVT(
*DAG.getContext()));
if (LD->getAlignment() < ABIAlignment){
Result = ExpandUnalignedLoad(cast<LoadSDNode>(Result.getNode()), DAG,
TLI);
Tmp3 = Result.getOperand(0);
Tmp4 = Result.getOperand(1);
Tmp3 = LegalizeOp(Tmp3);
Tmp4 = LegalizeOp(Tmp4);
}
}
break;
case TargetLowering::Custom:
Tmp1 = TLI.LowerOperation(Tmp3, DAG);
if (Tmp1.getNode()) {
Tmp3 = LegalizeOp(Tmp1);
Tmp4 = LegalizeOp(Tmp1.getValue(1));
}
break;
case TargetLowering::Promote: {
// Only promote a load of vector type to another.
assert(VT.isVector() && "Cannot promote this load!");
// Change base type to a different vector type.
MVT NVT = TLI.getTypeToPromoteTo(Node->getOpcode(), VT);
Tmp1 = DAG.getLoad(NVT, dl, Tmp1, Tmp2, LD->getSrcValue(),
LD->getSrcValueOffset(),
LD->isVolatile(), LD->getAlignment());
Tmp3 = LegalizeOp(DAG.getNode(ISD::BIT_CONVERT, dl, VT, Tmp1));
Tmp4 = LegalizeOp(Tmp1.getValue(1));
break;
}
}
// Since loads produce two values, make sure to remember that we
// legalized both of them.
AddLegalizedOperand(SDValue(Node, 0), Tmp3);
AddLegalizedOperand(SDValue(Node, 1), Tmp4);
return Op.getResNo() ? Tmp4 : Tmp3;
} else {
MVT SrcVT = LD->getMemoryVT();
unsigned SrcWidth = SrcVT.getSizeInBits();
int SVOffset = LD->getSrcValueOffset();
unsigned Alignment = LD->getAlignment();
bool isVolatile = LD->isVolatile();
if (SrcWidth != SrcVT.getStoreSizeInBits() &&
// Some targets pretend to have an i1 loading operation, and actually
// load an i8. This trick is correct for ZEXTLOAD because the top 7
// bits are guaranteed to be zero; it helps the optimizers understand
// that these bits are zero. It is also useful for EXTLOAD, since it
// tells the optimizers that those bits are undefined. It would be
// nice to have an effective generic way of getting these benefits...
// Until such a way is found, don't insist on promoting i1 here.
(SrcVT != MVT::i1 ||
TLI.getLoadExtAction(ExtType, MVT::i1) == TargetLowering::Promote)) {
// Promote to a byte-sized load if not loading an integral number of
// bytes. For example, promote EXTLOAD:i20 -> EXTLOAD:i24.
unsigned NewWidth = SrcVT.getStoreSizeInBits();
MVT NVT = MVT::getIntegerVT(NewWidth);
SDValue Ch;
// The extra bits are guaranteed to be zero, since we stored them that
// way. A zext load from NVT thus automatically gives zext from SrcVT.
ISD::LoadExtType NewExtType =
ExtType == ISD::ZEXTLOAD ? ISD::ZEXTLOAD : ISD::EXTLOAD;
Result = DAG.getExtLoad(NewExtType, dl, Node->getValueType(0),
Tmp1, Tmp2, LD->getSrcValue(), SVOffset,
NVT, isVolatile, Alignment);
Ch = Result.getValue(1); // The chain.
if (ExtType == ISD::SEXTLOAD)
// Having the top bits zero doesn't help when sign extending.
Result = DAG.getNode(ISD::SIGN_EXTEND_INREG, dl,
Result.getValueType(),
Result, DAG.getValueType(SrcVT));
else if (ExtType == ISD::ZEXTLOAD || NVT == Result.getValueType())
// All the top bits are guaranteed to be zero - inform the optimizers.
Result = DAG.getNode(ISD::AssertZext, dl,
Result.getValueType(), Result,
DAG.getValueType(SrcVT));
Tmp1 = LegalizeOp(Result);
Tmp2 = LegalizeOp(Ch);
} else if (SrcWidth & (SrcWidth - 1)) {
// If not loading a power-of-2 number of bits, expand as two loads.
assert(SrcVT.isExtended() && !SrcVT.isVector() &&
"Unsupported extload!");
unsigned RoundWidth = 1 << Log2_32(SrcWidth);
assert(RoundWidth < SrcWidth);
unsigned ExtraWidth = SrcWidth - RoundWidth;
assert(ExtraWidth < RoundWidth);
assert(!(RoundWidth % 8) && !(ExtraWidth % 8) &&
"Load size not an integral number of bytes!");
MVT RoundVT = MVT::getIntegerVT(RoundWidth);
MVT ExtraVT = MVT::getIntegerVT(ExtraWidth);
SDValue Lo, Hi, Ch;
unsigned IncrementSize;
if (TLI.isLittleEndian()) {
// EXTLOAD:i24 -> ZEXTLOAD:i16 | (shl EXTLOAD@+2:i8, 16)
// Load the bottom RoundWidth bits.
Lo = DAG.getExtLoad(ISD::ZEXTLOAD, dl,
Node->getValueType(0), Tmp1, Tmp2,
LD->getSrcValue(), SVOffset, RoundVT, isVolatile,
Alignment);
// Load the remaining ExtraWidth bits.
IncrementSize = RoundWidth / 8;
Tmp2 = DAG.getNode(ISD::ADD, dl, Tmp2.getValueType(), Tmp2,
DAG.getIntPtrConstant(IncrementSize));
Hi = DAG.getExtLoad(ExtType, dl, Node->getValueType(0), Tmp1, Tmp2,
LD->getSrcValue(), SVOffset + IncrementSize,
ExtraVT, isVolatile,
MinAlign(Alignment, IncrementSize));
// Build a factor node to remember that this load is independent of the
// other one.
Ch = DAG.getNode(ISD::TokenFactor, dl, MVT::Other, Lo.getValue(1),
Hi.getValue(1));
// Move the top bits to the right place.
Hi = DAG.getNode(ISD::SHL, dl, Hi.getValueType(), Hi,
DAG.getConstant(RoundWidth, TLI.getShiftAmountTy()));
// Join the hi and lo parts.
Result = DAG.getNode(ISD::OR, dl, Node->getValueType(0), Lo, Hi);
} else {
// Big endian - avoid unaligned loads.
// EXTLOAD:i24 -> (shl EXTLOAD:i16, 8) | ZEXTLOAD@+2:i8
// Load the top RoundWidth bits.
Hi = DAG.getExtLoad(ExtType, dl, Node->getValueType(0), Tmp1, Tmp2,
LD->getSrcValue(), SVOffset, RoundVT, isVolatile,
Alignment);
// Load the remaining ExtraWidth bits.
IncrementSize = RoundWidth / 8;
Tmp2 = DAG.getNode(ISD::ADD, dl, Tmp2.getValueType(), Tmp2,
DAG.getIntPtrConstant(IncrementSize));
Lo = DAG.getExtLoad(ISD::ZEXTLOAD, dl,
Node->getValueType(0), Tmp1, Tmp2,
LD->getSrcValue(), SVOffset + IncrementSize,
ExtraVT, isVolatile,
MinAlign(Alignment, IncrementSize));
// Build a factor node to remember that this load is independent of the
// other one.
Ch = DAG.getNode(ISD::TokenFactor, dl, MVT::Other, Lo.getValue(1),
Hi.getValue(1));
// Move the top bits to the right place.
Hi = DAG.getNode(ISD::SHL, dl, Hi.getValueType(), Hi,
DAG.getConstant(ExtraWidth, TLI.getShiftAmountTy()));
// Join the hi and lo parts.
Result = DAG.getNode(ISD::OR, dl, Node->getValueType(0), Lo, Hi);
}
Tmp1 = LegalizeOp(Result);
Tmp2 = LegalizeOp(Ch);
} else {
switch (TLI.getLoadExtAction(ExtType, SrcVT)) {
default: llvm_unreachable("This action is not supported yet!");
case TargetLowering::Custom:
isCustom = true;
// FALLTHROUGH
case TargetLowering::Legal:
Result = DAG.UpdateNodeOperands(Result, Tmp1, Tmp2, LD->getOffset());
Tmp1 = Result.getValue(0);
Tmp2 = Result.getValue(1);
if (isCustom) {
Tmp3 = TLI.LowerOperation(Result, DAG);
if (Tmp3.getNode()) {
Tmp1 = LegalizeOp(Tmp3);
Tmp2 = LegalizeOp(Tmp3.getValue(1));
}
} else {
// If this is an unaligned load and the target doesn't support it,
// expand it.
if (!TLI.allowsUnalignedMemoryAccesses()) {
unsigned ABIAlignment = TLI.getTargetData()->
getABITypeAlignment(LD->getMemoryVT().getTypeForMVT(
*DAG.getContext()));
if (LD->getAlignment() < ABIAlignment){
Result = ExpandUnalignedLoad(cast<LoadSDNode>(Result.getNode()), DAG,
TLI);
Tmp1 = Result.getOperand(0);
Tmp2 = Result.getOperand(1);
Tmp1 = LegalizeOp(Tmp1);
Tmp2 = LegalizeOp(Tmp2);
}
}
}
break;
case TargetLowering::Expand:
// f64 = EXTLOAD f32 should expand to LOAD, FP_EXTEND
if (SrcVT == MVT::f32 && Node->getValueType(0) == MVT::f64) {
SDValue Load = DAG.getLoad(SrcVT, dl, Tmp1, Tmp2, LD->getSrcValue(),
LD->getSrcValueOffset(),
LD->isVolatile(), LD->getAlignment());
Result = DAG.getNode(ISD::FP_EXTEND, dl,
Node->getValueType(0), Load);
Tmp1 = LegalizeOp(Result); // Relegalize new nodes.
Tmp2 = LegalizeOp(Load.getValue(1));
break;
}
assert(ExtType != ISD::EXTLOAD &&"EXTLOAD should always be supported!");
// Turn the unsupported load into an EXTLOAD followed by an explicit
// zero/sign extend inreg.
Result = DAG.getExtLoad(ISD::EXTLOAD, dl, Node->getValueType(0),
Tmp1, Tmp2, LD->getSrcValue(),
LD->getSrcValueOffset(), SrcVT,
LD->isVolatile(), LD->getAlignment());
SDValue ValRes;
if (ExtType == ISD::SEXTLOAD)
ValRes = DAG.getNode(ISD::SIGN_EXTEND_INREG, dl,
Result.getValueType(),
Result, DAG.getValueType(SrcVT));
else
ValRes = DAG.getZeroExtendInReg(Result, dl, SrcVT);
Tmp1 = LegalizeOp(ValRes); // Relegalize new nodes.
Tmp2 = LegalizeOp(Result.getValue(1)); // Relegalize new nodes.
break;
}
}
// Since loads produce two values, make sure to remember that we legalized
// both of them.
AddLegalizedOperand(SDValue(Node, 0), Tmp1);
AddLegalizedOperand(SDValue(Node, 1), Tmp2);
return Op.getResNo() ? Tmp2 : Tmp1;
}
}
case ISD::STORE: {
StoreSDNode *ST = cast<StoreSDNode>(Node);
Tmp1 = LegalizeOp(ST->getChain()); // Legalize the chain.
Tmp2 = LegalizeOp(ST->getBasePtr()); // Legalize the pointer.
int SVOffset = ST->getSrcValueOffset();
unsigned Alignment = ST->getAlignment();
bool isVolatile = ST->isVolatile();
if (!ST->isTruncatingStore()) {
if (SDNode *OptStore = OptimizeFloatStore(ST).getNode()) {
Result = SDValue(OptStore, 0);
break;
}
{
Tmp3 = LegalizeOp(ST->getValue());
Result = DAG.UpdateNodeOperands(Result, Tmp1, Tmp3, Tmp2,
ST->getOffset());
MVT VT = Tmp3.getValueType();
switch (TLI.getOperationAction(ISD::STORE, VT)) {
default: llvm_unreachable("This action is not supported yet!");
case TargetLowering::Legal:
// If this is an unaligned store and the target doesn't support it,
// expand it.
if (!TLI.allowsUnalignedMemoryAccesses()) {
unsigned ABIAlignment = TLI.getTargetData()->
getABITypeAlignment(ST->getMemoryVT().getTypeForMVT(
*DAG.getContext()));
if (ST->getAlignment() < ABIAlignment)
Result = ExpandUnalignedStore(cast<StoreSDNode>(Result.getNode()), DAG,
TLI);
}
break;
case TargetLowering::Custom:
Tmp1 = TLI.LowerOperation(Result, DAG);
if (Tmp1.getNode()) Result = Tmp1;
break;
case TargetLowering::Promote:
assert(VT.isVector() && "Unknown legal promote case!");
Tmp3 = DAG.getNode(ISD::BIT_CONVERT, dl,
TLI.getTypeToPromoteTo(ISD::STORE, VT), Tmp3);
Result = DAG.getStore(Tmp1, dl, Tmp3, Tmp2,
ST->getSrcValue(), SVOffset, isVolatile,
Alignment);
break;
}
break;
}
} else {
Tmp3 = LegalizeOp(ST->getValue());
MVT StVT = ST->getMemoryVT();
unsigned StWidth = StVT.getSizeInBits();
if (StWidth != StVT.getStoreSizeInBits()) {
// Promote to a byte-sized store with upper bits zero if not
// storing an integral number of bytes. For example, promote
// TRUNCSTORE:i1 X -> TRUNCSTORE:i8 (and X, 1)
MVT NVT = MVT::getIntegerVT(StVT.getStoreSizeInBits());
Tmp3 = DAG.getZeroExtendInReg(Tmp3, dl, StVT);
Result = DAG.getTruncStore(Tmp1, dl, Tmp3, Tmp2, ST->getSrcValue(),
SVOffset, NVT, isVolatile, Alignment);
} else if (StWidth & (StWidth - 1)) {
// If not storing a power-of-2 number of bits, expand as two stores.
assert(StVT.isExtended() && !StVT.isVector() &&
"Unsupported truncstore!");
unsigned RoundWidth = 1 << Log2_32(StWidth);
assert(RoundWidth < StWidth);
unsigned ExtraWidth = StWidth - RoundWidth;
assert(ExtraWidth < RoundWidth);
assert(!(RoundWidth % 8) && !(ExtraWidth % 8) &&
"Store size not an integral number of bytes!");
MVT RoundVT = MVT::getIntegerVT(RoundWidth);
MVT ExtraVT = MVT::getIntegerVT(ExtraWidth);
SDValue Lo, Hi;
unsigned IncrementSize;
if (TLI.isLittleEndian()) {
// TRUNCSTORE:i24 X -> TRUNCSTORE:i16 X, TRUNCSTORE@+2:i8 (srl X, 16)
// Store the bottom RoundWidth bits.
Lo = DAG.getTruncStore(Tmp1, dl, Tmp3, Tmp2, ST->getSrcValue(),
SVOffset, RoundVT,
isVolatile, Alignment);
// Store the remaining ExtraWidth bits.
IncrementSize = RoundWidth / 8;
Tmp2 = DAG.getNode(ISD::ADD, dl, Tmp2.getValueType(), Tmp2,
DAG.getIntPtrConstant(IncrementSize));
Hi = DAG.getNode(ISD::SRL, dl, Tmp3.getValueType(), Tmp3,
DAG.getConstant(RoundWidth, TLI.getShiftAmountTy()));
Hi = DAG.getTruncStore(Tmp1, dl, Hi, Tmp2, ST->getSrcValue(),
SVOffset + IncrementSize, ExtraVT, isVolatile,
MinAlign(Alignment, IncrementSize));
} else {
// Big endian - avoid unaligned stores.
// TRUNCSTORE:i24 X -> TRUNCSTORE:i16 (srl X, 8), TRUNCSTORE@+2:i8 X
// Store the top RoundWidth bits.
Hi = DAG.getNode(ISD::SRL, dl, Tmp3.getValueType(), Tmp3,
DAG.getConstant(ExtraWidth, TLI.getShiftAmountTy()));
Hi = DAG.getTruncStore(Tmp1, dl, Hi, Tmp2, ST->getSrcValue(),
SVOffset, RoundVT, isVolatile, Alignment);
// Store the remaining ExtraWidth bits.
IncrementSize = RoundWidth / 8;
Tmp2 = DAG.getNode(ISD::ADD, dl, Tmp2.getValueType(), Tmp2,
DAG.getIntPtrConstant(IncrementSize));
Lo = DAG.getTruncStore(Tmp1, dl, Tmp3, Tmp2, ST->getSrcValue(),
SVOffset + IncrementSize, ExtraVT, isVolatile,
MinAlign(Alignment, IncrementSize));
}
// The order of the stores doesn't matter.
Result = DAG.getNode(ISD::TokenFactor, dl, MVT::Other, Lo, Hi);
} else {
if (Tmp1 != ST->getChain() || Tmp3 != ST->getValue() ||
Tmp2 != ST->getBasePtr())
Result = DAG.UpdateNodeOperands(Result, Tmp1, Tmp3, Tmp2,
ST->getOffset());
switch (TLI.getTruncStoreAction(ST->getValue().getValueType(), StVT)) {
default: llvm_unreachable("This action is not supported yet!");
case TargetLowering::Legal:
// If this is an unaligned store and the target doesn't support it,
// expand it.
if (!TLI.allowsUnalignedMemoryAccesses()) {
unsigned ABIAlignment = TLI.getTargetData()->
getABITypeAlignment(ST->getMemoryVT().getTypeForMVT(
*DAG.getContext()));
if (ST->getAlignment() < ABIAlignment)
Result = ExpandUnalignedStore(cast<StoreSDNode>(Result.getNode()), DAG,
TLI);
}
break;
case TargetLowering::Custom:
Result = TLI.LowerOperation(Result, DAG);
break;
case Expand:
// TRUNCSTORE:i16 i32 -> STORE i16
assert(isTypeLegal(StVT) && "Do not know how to expand this store!");
Tmp3 = DAG.getNode(ISD::TRUNCATE, dl, StVT, Tmp3);
Result = DAG.getStore(Tmp1, dl, Tmp3, Tmp2, ST->getSrcValue(),
SVOffset, isVolatile, Alignment);
break;
}
}
}
break;
}
}
assert(Result.getValueType() == Op.getValueType() &&
"Bad legalization!");
// Make sure that the generated code is itself legal.
if (Result != Op)
Result = LegalizeOp(Result);
// Note that LegalizeOp may be reentered even from single-use nodes, which
// means that we always must cache transformed nodes.
AddLegalizedOperand(Op, Result);
return Result;
}
SDValue SelectionDAGLegalize::ExpandExtractFromVectorThroughStack(SDValue Op) {
SDValue Vec = Op.getOperand(0);
SDValue Idx = Op.getOperand(1);
DebugLoc dl = Op.getDebugLoc();
// Store the value to a temporary stack slot, then LOAD the returned part.
SDValue StackPtr = DAG.CreateStackTemporary(Vec.getValueType());
SDValue Ch = DAG.getStore(DAG.getEntryNode(), dl, Vec, StackPtr, NULL, 0);
// Add the offset to the index.
unsigned EltSize =
Vec.getValueType().getVectorElementType().getSizeInBits()/8;
Idx = DAG.getNode(ISD::MUL, dl, Idx.getValueType(), Idx,
DAG.getConstant(EltSize, Idx.getValueType()));
if (Idx.getValueType().bitsGT(TLI.getPointerTy()))
Idx = DAG.getNode(ISD::TRUNCATE, dl, TLI.getPointerTy(), Idx);
else
Idx = DAG.getNode(ISD::ZERO_EXTEND, dl, TLI.getPointerTy(), Idx);
StackPtr = DAG.getNode(ISD::ADD, dl, Idx.getValueType(), Idx, StackPtr);
if (Op.getValueType().isVector())
return DAG.getLoad(Op.getValueType(), dl, Ch, StackPtr, NULL, 0);
else
return DAG.getExtLoad(ISD::EXTLOAD, dl, Op.getValueType(), Ch, StackPtr,
NULL, 0, Vec.getValueType().getVectorElementType());
}
SDValue SelectionDAGLegalize::ExpandVectorBuildThroughStack(SDNode* Node) {
// We can't handle this case efficiently. Allocate a sufficiently
// aligned object on the stack, store each element into it, then load
// the result as a vector.
// Create the stack frame object.
MVT VT = Node->getValueType(0);
MVT OpVT = Node->getOperand(0).getValueType();
DebugLoc dl = Node->getDebugLoc();
SDValue FIPtr = DAG.CreateStackTemporary(VT);
int FI = cast<FrameIndexSDNode>(FIPtr.getNode())->getIndex();
const Value *SV = PseudoSourceValue::getFixedStack(FI);
// Emit a store of each element to the stack slot.
SmallVector<SDValue, 8> Stores;
unsigned TypeByteSize = OpVT.getSizeInBits() / 8;
// Store (in the right endianness) the elements to memory.
for (unsigned i = 0, e = Node->getNumOperands(); i != e; ++i) {
// Ignore undef elements.
if (Node->getOperand(i).getOpcode() == ISD::UNDEF) continue;
unsigned Offset = TypeByteSize*i;
SDValue Idx = DAG.getConstant(Offset, FIPtr.getValueType());
Idx = DAG.getNode(ISD::ADD, dl, FIPtr.getValueType(), FIPtr, Idx);
Stores.push_back(DAG.getStore(DAG.getEntryNode(), dl, Node->getOperand(i),
Idx, SV, Offset));
}
SDValue StoreChain;
if (!Stores.empty()) // Not all undef elements?
StoreChain = DAG.getNode(ISD::TokenFactor, dl, MVT::Other,
&Stores[0], Stores.size());
else
StoreChain = DAG.getEntryNode();
// Result is a load from the stack slot.
return DAG.getLoad(VT, dl, StoreChain, FIPtr, SV, 0);
}
SDValue SelectionDAGLegalize::ExpandFCOPYSIGN(SDNode* Node) {
DebugLoc dl = Node->getDebugLoc();
SDValue Tmp1 = Node->getOperand(0);
SDValue Tmp2 = Node->getOperand(1);
assert((Tmp2.getValueType() == MVT::f32 ||
Tmp2.getValueType() == MVT::f64) &&
"Ugly special-cased code!");
// Get the sign bit of the RHS.
SDValue SignBit;
MVT IVT = Tmp2.getValueType() == MVT::f64 ? MVT::i64 : MVT::i32;
if (isTypeLegal(IVT)) {
SignBit = DAG.getNode(ISD::BIT_CONVERT, dl, IVT, Tmp2);
} else {
assert(isTypeLegal(TLI.getPointerTy()) &&
(TLI.getPointerTy() == MVT::i32 ||
TLI.getPointerTy() == MVT::i64) &&
"Legal type for load?!");
SDValue StackPtr = DAG.CreateStackTemporary(Tmp2.getValueType());
SDValue StorePtr = StackPtr, LoadPtr = StackPtr;
SDValue Ch =
DAG.getStore(DAG.getEntryNode(), dl, Tmp2, StorePtr, NULL, 0);
if (Tmp2.getValueType() == MVT::f64 && TLI.isLittleEndian())
LoadPtr = DAG.getNode(ISD::ADD, dl, StackPtr.getValueType(),
LoadPtr, DAG.getIntPtrConstant(4));
SignBit = DAG.getExtLoad(ISD::SEXTLOAD, dl, TLI.getPointerTy(),
Ch, LoadPtr, NULL, 0, MVT::i32);
}
SignBit =
DAG.getSetCC(dl, TLI.getSetCCResultType(SignBit.getValueType()),
SignBit, DAG.getConstant(0, SignBit.getValueType()),
ISD::SETLT);
// Get the absolute value of the result.
SDValue AbsVal = DAG.getNode(ISD::FABS, dl, Tmp1.getValueType(), Tmp1);
// Select between the nabs and abs value based on the sign bit of
// the input.
return DAG.getNode(ISD::SELECT, dl, AbsVal.getValueType(), SignBit,
DAG.getNode(ISD::FNEG, dl, AbsVal.getValueType(), AbsVal),
AbsVal);
}
SDValue SelectionDAGLegalize::ExpandDBG_STOPPOINT(SDNode* Node) {
DebugLoc dl = Node->getDebugLoc();
DwarfWriter *DW = DAG.getDwarfWriter();
bool useDEBUG_LOC = TLI.isOperationLegalOrCustom(ISD::DEBUG_LOC,
MVT::Other);
bool useLABEL = TLI.isOperationLegalOrCustom(ISD::DBG_LABEL, MVT::Other);
const DbgStopPointSDNode *DSP = cast<DbgStopPointSDNode>(Node);
GlobalVariable *CU_GV = cast<GlobalVariable>(DSP->getCompileUnit());
if (DW && (useDEBUG_LOC || useLABEL) && !CU_GV->isDeclaration()) {
DICompileUnit CU(cast<GlobalVariable>(DSP->getCompileUnit()));
unsigned Line = DSP->getLine();
unsigned Col = DSP->getColumn();
if (OptLevel == CodeGenOpt::None) {
// A bit self-referential to have DebugLoc on Debug_Loc nodes, but it
// won't hurt anything.
if (useDEBUG_LOC) {
return DAG.getNode(ISD::DEBUG_LOC, dl, MVT::Other, Node->getOperand(0),
DAG.getConstant(Line, MVT::i32),
DAG.getConstant(Col, MVT::i32),
DAG.getSrcValue(CU.getGV()));
} else {
unsigned ID = DW->RecordSourceLine(Line, Col, CU);
return DAG.getLabel(ISD::DBG_LABEL, dl, Node->getOperand(0), ID);
}
}
}
return Node->getOperand(0);
}
void SelectionDAGLegalize::ExpandDYNAMIC_STACKALLOC(SDNode* Node,
SmallVectorImpl<SDValue> &Results) {
unsigned SPReg = TLI.getStackPointerRegisterToSaveRestore();
assert(SPReg && "Target cannot require DYNAMIC_STACKALLOC expansion and"
" not tell us which reg is the stack pointer!");
DebugLoc dl = Node->getDebugLoc();
MVT VT = Node->getValueType(0);
SDValue Tmp1 = SDValue(Node, 0);
SDValue Tmp2 = SDValue(Node, 1);
SDValue Tmp3 = Node->getOperand(2);
SDValue Chain = Tmp1.getOperand(0);
// Chain the dynamic stack allocation so that it doesn't modify the stack
// pointer when other instructions are using the stack.
Chain = DAG.getCALLSEQ_START(Chain, DAG.getIntPtrConstant(0, true));
SDValue Size = Tmp2.getOperand(1);
SDValue SP = DAG.getCopyFromReg(Chain, dl, SPReg, VT);
Chain = SP.getValue(1);
unsigned Align = cast<ConstantSDNode>(Tmp3)->getZExtValue();
unsigned StackAlign =
TLI.getTargetMachine().getFrameInfo()->getStackAlignment();
if (Align > StackAlign)
SP = DAG.getNode(ISD::AND, dl, VT, SP,
DAG.getConstant(-(uint64_t)Align, VT));
Tmp1 = DAG.getNode(ISD::SUB, dl, VT, SP, Size); // Value
Chain = DAG.getCopyToReg(Chain, dl, SPReg, Tmp1); // Output chain
Tmp2 = DAG.getCALLSEQ_END(Chain, DAG.getIntPtrConstant(0, true),
DAG.getIntPtrConstant(0, true), SDValue());
Results.push_back(Tmp1);
Results.push_back(Tmp2);
}
/// LegalizeSetCCCondCode - Legalize a SETCC with given LHS and RHS and
/// condition code CC on the current target. This routine assumes LHS and rHS
/// have already been legalized by LegalizeSetCCOperands. It expands SETCC with
/// illegal condition code into AND / OR of multiple SETCC values.
void SelectionDAGLegalize::LegalizeSetCCCondCode(MVT VT,
SDValue &LHS, SDValue &RHS,
SDValue &CC,
DebugLoc dl) {
MVT OpVT = LHS.getValueType();
ISD::CondCode CCCode = cast<CondCodeSDNode>(CC)->get();
switch (TLI.getCondCodeAction(CCCode, OpVT)) {
default: llvm_unreachable("Unknown condition code action!");
case TargetLowering::Legal:
// Nothing to do.
break;
case TargetLowering::Expand: {
ISD::CondCode CC1 = ISD::SETCC_INVALID, CC2 = ISD::SETCC_INVALID;
unsigned Opc = 0;
switch (CCCode) {
default: llvm_unreachable("Don't know how to expand this condition!");
case ISD::SETOEQ: CC1 = ISD::SETEQ; CC2 = ISD::SETO; Opc = ISD::AND; break;
case ISD::SETOGT: CC1 = ISD::SETGT; CC2 = ISD::SETO; Opc = ISD::AND; break;
case ISD::SETOGE: CC1 = ISD::SETGE; CC2 = ISD::SETO; Opc = ISD::AND; break;
case ISD::SETOLT: CC1 = ISD::SETLT; CC2 = ISD::SETO; Opc = ISD::AND; break;
case ISD::SETOLE: CC1 = ISD::SETLE; CC2 = ISD::SETO; Opc = ISD::AND; break;
case ISD::SETONE: CC1 = ISD::SETNE; CC2 = ISD::SETO; Opc = ISD::AND; break;
case ISD::SETUEQ: CC1 = ISD::SETEQ; CC2 = ISD::SETUO; Opc = ISD::OR; break;
case ISD::SETUGT: CC1 = ISD::SETGT; CC2 = ISD::SETUO; Opc = ISD::OR; break;
case ISD::SETUGE: CC1 = ISD::SETGE; CC2 = ISD::SETUO; Opc = ISD::OR; break;
case ISD::SETULT: CC1 = ISD::SETLT; CC2 = ISD::SETUO; Opc = ISD::OR; break;
case ISD::SETULE: CC1 = ISD::SETLE; CC2 = ISD::SETUO; Opc = ISD::OR; break;
case ISD::SETUNE: CC1 = ISD::SETNE; CC2 = ISD::SETUO; Opc = ISD::OR; break;
// FIXME: Implement more expansions.
}
SDValue SetCC1 = DAG.getSetCC(dl, VT, LHS, RHS, CC1);
SDValue SetCC2 = DAG.getSetCC(dl, VT, LHS, RHS, CC2);
LHS = DAG.getNode(Opc, dl, VT, SetCC1, SetCC2);
RHS = SDValue();
CC = SDValue();
break;
}
}
}
/// EmitStackConvert - Emit a store/load combination to the stack. This stores
/// SrcOp to a stack slot of type SlotVT, truncating it if needed. It then does
/// a load from the stack slot to DestVT, extending it if needed.
/// The resultant code need not be legal.
SDValue SelectionDAGLegalize::EmitStackConvert(SDValue SrcOp,
MVT SlotVT,
MVT DestVT,
DebugLoc dl) {
// Create the stack frame object.
unsigned SrcAlign =
TLI.getTargetData()->getPrefTypeAlignment(SrcOp.getValueType().
getTypeForMVT(*DAG.getContext()));
SDValue FIPtr = DAG.CreateStackTemporary(SlotVT, SrcAlign);
FrameIndexSDNode *StackPtrFI = cast<FrameIndexSDNode>(FIPtr);
int SPFI = StackPtrFI->getIndex();
const Value *SV = PseudoSourceValue::getFixedStack(SPFI);
unsigned SrcSize = SrcOp.getValueType().getSizeInBits();
unsigned SlotSize = SlotVT.getSizeInBits();
unsigned DestSize = DestVT.getSizeInBits();
unsigned DestAlign =
TLI.getTargetData()->getPrefTypeAlignment(DestVT.getTypeForMVT(
*DAG.getContext()));
// Emit a store to the stack slot. Use a truncstore if the input value is
// later than DestVT.
SDValue Store;
if (SrcSize > SlotSize)
Store = DAG.getTruncStore(DAG.getEntryNode(), dl, SrcOp, FIPtr,
SV, 0, SlotVT, false, SrcAlign);
else {
assert(SrcSize == SlotSize && "Invalid store");
Store = DAG.getStore(DAG.getEntryNode(), dl, SrcOp, FIPtr,
SV, 0, false, SrcAlign);
}
// Result is a load from the stack slot.
if (SlotSize == DestSize)
return DAG.getLoad(DestVT, dl, Store, FIPtr, SV, 0, false, DestAlign);
assert(SlotSize < DestSize && "Unknown extension!");
return DAG.getExtLoad(ISD::EXTLOAD, dl, DestVT, Store, FIPtr, SV, 0, SlotVT,
false, DestAlign);
}
SDValue SelectionDAGLegalize::ExpandSCALAR_TO_VECTOR(SDNode *Node) {
DebugLoc dl = Node->getDebugLoc();
// Create a vector sized/aligned stack slot, store the value to element #0,
// then load the whole vector back out.
SDValue StackPtr = DAG.CreateStackTemporary(Node->getValueType(0));
FrameIndexSDNode *StackPtrFI = cast<FrameIndexSDNode>(StackPtr);
int SPFI = StackPtrFI->getIndex();
SDValue Ch = DAG.getTruncStore(DAG.getEntryNode(), dl, Node->getOperand(0),
StackPtr,
PseudoSourceValue::getFixedStack(SPFI), 0,
Node->getValueType(0).getVectorElementType());
return DAG.getLoad(Node->getValueType(0), dl, Ch, StackPtr,
PseudoSourceValue::getFixedStack(SPFI), 0);
}
/// ExpandBUILD_VECTOR - Expand a BUILD_VECTOR node on targets that don't
/// support the operation, but do support the resultant vector type.
SDValue SelectionDAGLegalize::ExpandBUILD_VECTOR(SDNode *Node) {
LLVMContext *Context = DAG.getContext();
unsigned NumElems = Node->getNumOperands();
SDValue Value1, Value2;
DebugLoc dl = Node->getDebugLoc();
MVT VT = Node->getValueType(0);
MVT OpVT = Node->getOperand(0).getValueType();
MVT EltVT = VT.getVectorElementType();
// If the only non-undef value is the low element, turn this into a
// SCALAR_TO_VECTOR node. If this is { X, X, X, X }, determine X.
bool isOnlyLowElement = true;
bool MoreThanTwoValues = false;
bool isConstant = true;
for (unsigned i = 0; i < NumElems; ++i) {
SDValue V = Node->getOperand(i);
if (V.getOpcode() == ISD::UNDEF)
continue;
if (i > 0)
isOnlyLowElement = false;
if (!isa<ConstantFPSDNode>(V) && !isa<ConstantSDNode>(V))
isConstant = false;
if (!Value1.getNode()) {
Value1 = V;
} else if (!Value2.getNode()) {
if (V != Value1)
Value2 = V;
} else if (V != Value1 && V != Value2) {
MoreThanTwoValues = true;
}
}
if (!Value1.getNode())
return DAG.getUNDEF(VT);
if (isOnlyLowElement)
return DAG.getNode(ISD::SCALAR_TO_VECTOR, dl, VT, Node->getOperand(0));
// If all elements are constants, create a load from the constant pool.
if (isConstant) {
std::vector<Constant*> CV;
for (unsigned i = 0, e = NumElems; i != e; ++i) {
if (ConstantFPSDNode *V =
dyn_cast<ConstantFPSDNode>(Node->getOperand(i))) {
CV.push_back(const_cast<ConstantFP *>(V->getConstantFPValue()));
} else if (ConstantSDNode *V =
dyn_cast<ConstantSDNode>(Node->getOperand(i))) {
CV.push_back(const_cast<ConstantInt *>(V->getConstantIntValue()));
} else {
assert(Node->getOperand(i).getOpcode() == ISD::UNDEF);
const Type *OpNTy = OpVT.getTypeForMVT(*DAG.getContext());
CV.push_back(Context->getUndef(OpNTy));
}
}
Constant *CP = Context->getConstantVector(CV);
SDValue CPIdx = DAG.getConstantPool(CP, TLI.getPointerTy());
unsigned Alignment = cast<ConstantPoolSDNode>(CPIdx)->getAlignment();
return DAG.getLoad(VT, dl, DAG.getEntryNode(), CPIdx,
PseudoSourceValue::getConstantPool(), 0,
false, Alignment);
}
if (!MoreThanTwoValues) {
SmallVector<int, 8> ShuffleVec(NumElems, -1);
for (unsigned i = 0; i < NumElems; ++i) {
SDValue V = Node->getOperand(i);
if (V.getOpcode() == ISD::UNDEF)
continue;
ShuffleVec[i] = V == Value1 ? 0 : NumElems;
}
if (TLI.isShuffleMaskLegal(ShuffleVec, Node->getValueType(0))) {
// Get the splatted value into the low element of a vector register.
SDValue Vec1 = DAG.getNode(ISD::SCALAR_TO_VECTOR, dl, VT, Value1);
SDValue Vec2;
if (Value2.getNode())
Vec2 = DAG.getNode(ISD::SCALAR_TO_VECTOR, dl, VT, Value2);
else
Vec2 = DAG.getUNDEF(VT);
// Return shuffle(LowValVec, undef, <0,0,0,0>)
return DAG.getVectorShuffle(VT, dl, Vec1, Vec2, ShuffleVec.data());
}
}
// Otherwise, we can't handle this case efficiently.
return ExpandVectorBuildThroughStack(Node);
}
// ExpandLibCall - Expand a node into a call to a libcall. If the result value
// does not fit into a register, return the lo part and set the hi part to the
// by-reg argument. If it does fit into a single register, return the result
// and leave the Hi part unset.
SDValue SelectionDAGLegalize::ExpandLibCall(RTLIB::Libcall LC, SDNode *Node,
bool isSigned) {
assert(!IsLegalizingCall && "Cannot overlap legalization of calls!");
// The input chain to this libcall is the entry node of the function.
// Legalizing the call will automatically add the previous call to the
// dependence.
SDValue InChain = DAG.getEntryNode();
TargetLowering::ArgListTy Args;
TargetLowering::ArgListEntry Entry;
for (unsigned i = 0, e = Node->getNumOperands(); i != e; ++i) {
MVT ArgVT = Node->getOperand(i).getValueType();
const Type *ArgTy = ArgVT.getTypeForMVT(*DAG.getContext());
Entry.Node = Node->getOperand(i); Entry.Ty = ArgTy;
Entry.isSExt = isSigned;
Entry.isZExt = !isSigned;
Args.push_back(Entry);
}
SDValue Callee = DAG.getExternalSymbol(TLI.getLibcallName(LC),
TLI.getPointerTy());
// Splice the libcall in wherever FindInputOutputChains tells us to.
const Type *RetTy = Node->getValueType(0).getTypeForMVT(*DAG.getContext());
std::pair<SDValue, SDValue> CallInfo =
TLI.LowerCallTo(InChain, RetTy, isSigned, !isSigned, false, false,
0, CallingConv::C, false, Callee, Args, DAG,
Node->getDebugLoc());
// Legalize the call sequence, starting with the chain. This will advance
// the LastCALLSEQ_END to the legalized version of the CALLSEQ_END node that
// was added by LowerCallTo (guaranteeing proper serialization of calls).
LegalizeOp(CallInfo.second);
return CallInfo.first;
}
SDValue SelectionDAGLegalize::ExpandFPLibCall(SDNode* Node,
RTLIB::Libcall Call_F32,
RTLIB::Libcall Call_F64,
RTLIB::Libcall Call_F80,
RTLIB::Libcall Call_PPCF128) {
RTLIB::Libcall LC;
switch (Node->getValueType(0).getSimpleVT()) {
default: llvm_unreachable("Unexpected request for libcall!");
case MVT::f32: LC = Call_F32; break;
case MVT::f64: LC = Call_F64; break;
case MVT::f80: LC = Call_F80; break;
case MVT::ppcf128: LC = Call_PPCF128; break;
}
return ExpandLibCall(LC, Node, false);
}
SDValue SelectionDAGLegalize::ExpandIntLibCall(SDNode* Node, bool isSigned,
RTLIB::Libcall Call_I16,
RTLIB::Libcall Call_I32,
RTLIB::Libcall Call_I64,
RTLIB::Libcall Call_I128) {
RTLIB::Libcall LC;
switch (Node->getValueType(0).getSimpleVT()) {
default: llvm_unreachable("Unexpected request for libcall!");
case MVT::i16: LC = Call_I16; break;
case MVT::i32: LC = Call_I32; break;
case MVT::i64: LC = Call_I64; break;
case MVT::i128: LC = Call_I128; break;
}
return ExpandLibCall(LC, Node, isSigned);
}
/// ExpandLegalINT_TO_FP - This function is responsible for legalizing a
/// INT_TO_FP operation of the specified operand when the target requests that
/// we expand it. At this point, we know that the result and operand types are
/// legal for the target.
SDValue SelectionDAGLegalize::ExpandLegalINT_TO_FP(bool isSigned,
SDValue Op0,
MVT DestVT,
DebugLoc dl) {
if (Op0.getValueType() == MVT::i32) {
// simple 32-bit [signed|unsigned] integer to float/double expansion
// Get the stack frame index of a 8 byte buffer.
SDValue StackSlot = DAG.CreateStackTemporary(MVT::f64);
// word offset constant for Hi/Lo address computation
SDValue WordOff = DAG.getConstant(sizeof(int), TLI.getPointerTy());
// set up Hi and Lo (into buffer) address based on endian
SDValue Hi = StackSlot;
SDValue Lo = DAG.getNode(ISD::ADD, dl,
TLI.getPointerTy(), StackSlot, WordOff);
if (TLI.isLittleEndian())
std::swap(Hi, Lo);
// if signed map to unsigned space
SDValue Op0Mapped;
if (isSigned) {
// constant used to invert sign bit (signed to unsigned mapping)
SDValue SignBit = DAG.getConstant(0x80000000u, MVT::i32);
Op0Mapped = DAG.getNode(ISD::XOR, dl, MVT::i32, Op0, SignBit);
} else {
Op0Mapped = Op0;
}
// store the lo of the constructed double - based on integer input
SDValue Store1 = DAG.getStore(DAG.getEntryNode(), dl,
Op0Mapped, Lo, NULL, 0);
// initial hi portion of constructed double
SDValue InitialHi = DAG.getConstant(0x43300000u, MVT::i32);
// store the hi of the constructed double - biased exponent
SDValue Store2=DAG.getStore(Store1, dl, InitialHi, Hi, NULL, 0);
// load the constructed double
SDValue Load = DAG.getLoad(MVT::f64, dl, Store2, StackSlot, NULL, 0);
// FP constant to bias correct the final result
SDValue Bias = DAG.getConstantFP(isSigned ?
BitsToDouble(0x4330000080000000ULL) :
BitsToDouble(0x4330000000000000ULL),
MVT::f64);
// subtract the bias
SDValue Sub = DAG.getNode(ISD::FSUB, dl, MVT::f64, Load, Bias);
// final result
SDValue Result;
// handle final rounding
if (DestVT == MVT::f64) {
// do nothing
Result = Sub;
} else if (DestVT.bitsLT(MVT::f64)) {
Result = DAG.getNode(ISD::FP_ROUND, dl, DestVT, Sub,
DAG.getIntPtrConstant(0));
} else if (DestVT.bitsGT(MVT::f64)) {
Result = DAG.getNode(ISD::FP_EXTEND, dl, DestVT, Sub);
}
return Result;
}
assert(!isSigned && "Legalize cannot Expand SINT_TO_FP for i64 yet");
SDValue Tmp1 = DAG.getNode(ISD::SINT_TO_FP, dl, DestVT, Op0);
SDValue SignSet = DAG.getSetCC(dl, TLI.getSetCCResultType(Op0.getValueType()),
Op0, DAG.getConstant(0, Op0.getValueType()),
ISD::SETLT);
SDValue Zero = DAG.getIntPtrConstant(0), Four = DAG.getIntPtrConstant(4);
SDValue CstOffset = DAG.getNode(ISD::SELECT, dl, Zero.getValueType(),
SignSet, Four, Zero);
// If the sign bit of the integer is set, the large number will be treated
// as a negative number. To counteract this, the dynamic code adds an
// offset depending on the data type.
uint64_t FF;
switch (Op0.getValueType().getSimpleVT()) {
default: llvm_unreachable("Unsupported integer type!");
case MVT::i8 : FF = 0x43800000ULL; break; // 2^8 (as a float)
case MVT::i16: FF = 0x47800000ULL; break; // 2^16 (as a float)
case MVT::i32: FF = 0x4F800000ULL; break; // 2^32 (as a float)
case MVT::i64: FF = 0x5F800000ULL; break; // 2^64 (as a float)
}
if (TLI.isLittleEndian()) FF <<= 32;
Constant *FudgeFactor = DAG.getContext()->getConstantInt(Type::Int64Ty, FF);
SDValue CPIdx = DAG.getConstantPool(FudgeFactor, TLI.getPointerTy());
unsigned Alignment = cast<ConstantPoolSDNode>(CPIdx)->getAlignment();
CPIdx = DAG.getNode(ISD::ADD, dl, TLI.getPointerTy(), CPIdx, CstOffset);
Alignment = std::min(Alignment, 4u);
SDValue FudgeInReg;
if (DestVT == MVT::f32)
FudgeInReg = DAG.getLoad(MVT::f32, dl, DAG.getEntryNode(), CPIdx,
PseudoSourceValue::getConstantPool(), 0,
false, Alignment);
else {
FudgeInReg =
LegalizeOp(DAG.getExtLoad(ISD::EXTLOAD, dl, DestVT,
DAG.getEntryNode(), CPIdx,
PseudoSourceValue::getConstantPool(), 0,
MVT::f32, false, Alignment));
}
return DAG.getNode(ISD::FADD, dl, DestVT, Tmp1, FudgeInReg);
}
/// PromoteLegalINT_TO_FP - This function is responsible for legalizing a
/// *INT_TO_FP operation of the specified operand when the target requests that
/// we promote it. At this point, we know that the result and operand types are
/// legal for the target, and that there is a legal UINT_TO_FP or SINT_TO_FP
/// operation that takes a larger input.
SDValue SelectionDAGLegalize::PromoteLegalINT_TO_FP(SDValue LegalOp,
MVT DestVT,
bool isSigned,
DebugLoc dl) {
// First step, figure out the appropriate *INT_TO_FP operation to use.
MVT NewInTy = LegalOp.getValueType();
unsigned OpToUse = 0;
// Scan for the appropriate larger type to use.
while (1) {
NewInTy = (MVT::SimpleValueType)(NewInTy.getSimpleVT()+1);
assert(NewInTy.isInteger() && "Ran out of possibilities!");
// If the target supports SINT_TO_FP of this type, use it.
if (TLI.isOperationLegalOrCustom(ISD::SINT_TO_FP, NewInTy)) {
OpToUse = ISD::SINT_TO_FP;
break;
}
if (isSigned) continue;
// If the target supports UINT_TO_FP of this type, use it.
if (TLI.isOperationLegalOrCustom(ISD::UINT_TO_FP, NewInTy)) {
OpToUse = ISD::UINT_TO_FP;
break;
}
// Otherwise, try a larger type.
}
// Okay, we found the operation and type to use. Zero extend our input to the
// desired type then run the operation on it.
return DAG.getNode(OpToUse, dl, DestVT,
DAG.getNode(isSigned ? ISD::SIGN_EXTEND : ISD::ZERO_EXTEND,
dl, NewInTy, LegalOp));
}
/// PromoteLegalFP_TO_INT - This function is responsible for legalizing a
/// FP_TO_*INT operation of the specified operand when the target requests that
/// we promote it. At this point, we know that the result and operand types are
/// legal for the target, and that there is a legal FP_TO_UINT or FP_TO_SINT
/// operation that returns a larger result.
SDValue SelectionDAGLegalize::PromoteLegalFP_TO_INT(SDValue LegalOp,
MVT DestVT,
bool isSigned,
DebugLoc dl) {
// First step, figure out the appropriate FP_TO*INT operation to use.
MVT NewOutTy = DestVT;
unsigned OpToUse = 0;
// Scan for the appropriate larger type to use.
while (1) {
NewOutTy = (MVT::SimpleValueType)(NewOutTy.getSimpleVT()+1);
assert(NewOutTy.isInteger() && "Ran out of possibilities!");
if (TLI.isOperationLegalOrCustom(ISD::FP_TO_SINT, NewOutTy)) {
OpToUse = ISD::FP_TO_SINT;
break;
}
if (TLI.isOperationLegalOrCustom(ISD::FP_TO_UINT, NewOutTy)) {
OpToUse = ISD::FP_TO_UINT;
break;
}
// Otherwise, try a larger type.
}
// Okay, we found the operation and type to use.
SDValue Operation = DAG.getNode(OpToUse, dl, NewOutTy, LegalOp);
// Truncate the result of the extended FP_TO_*INT operation to the desired
// size.
return DAG.getNode(ISD::TRUNCATE, dl, DestVT, Operation);
}
/// ExpandBSWAP - Open code the operations for BSWAP of the specified operation.
///
SDValue SelectionDAGLegalize::ExpandBSWAP(SDValue Op, DebugLoc dl) {
MVT VT = Op.getValueType();
MVT SHVT = TLI.getShiftAmountTy();
SDValue Tmp1, Tmp2, Tmp3, Tmp4, Tmp5, Tmp6, Tmp7, Tmp8;
switch (VT.getSimpleVT()) {
default: llvm_unreachable("Unhandled Expand type in BSWAP!");
case MVT::i16:
Tmp2 = DAG.getNode(ISD::SHL, dl, VT, Op, DAG.getConstant(8, SHVT));
Tmp1 = DAG.getNode(ISD::SRL, dl, VT, Op, DAG.getConstant(8, SHVT));
return DAG.getNode(ISD::OR, dl, VT, Tmp1, Tmp2);
case MVT::i32:
Tmp4 = DAG.getNode(ISD::SHL, dl, VT, Op, DAG.getConstant(24, SHVT));
Tmp3 = DAG.getNode(ISD::SHL, dl, VT, Op, DAG.getConstant(8, SHVT));
Tmp2 = DAG.getNode(ISD::SRL, dl, VT, Op, DAG.getConstant(8, SHVT));
Tmp1 = DAG.getNode(ISD::SRL, dl, VT, Op, DAG.getConstant(24, SHVT));
Tmp3 = DAG.getNode(ISD::AND, dl, VT, Tmp3, DAG.getConstant(0xFF0000, VT));
Tmp2 = DAG.getNode(ISD::AND, dl, VT, Tmp2, DAG.getConstant(0xFF00, VT));
Tmp4 = DAG.getNode(ISD::OR, dl, VT, Tmp4, Tmp3);
Tmp2 = DAG.getNode(ISD::OR, dl, VT, Tmp2, Tmp1);
return DAG.getNode(ISD::OR, dl, VT, Tmp4, Tmp2);
case MVT::i64:
Tmp8 = DAG.getNode(ISD::SHL, dl, VT, Op, DAG.getConstant(56, SHVT));
Tmp7 = DAG.getNode(ISD::SHL, dl, VT, Op, DAG.getConstant(40, SHVT));
Tmp6 = DAG.getNode(ISD::SHL, dl, VT, Op, DAG.getConstant(24, SHVT));
Tmp5 = DAG.getNode(ISD::SHL, dl, VT, Op, DAG.getConstant(8, SHVT));
Tmp4 = DAG.getNode(ISD::SRL, dl, VT, Op, DAG.getConstant(8, SHVT));
Tmp3 = DAG.getNode(ISD::SRL, dl, VT, Op, DAG.getConstant(24, SHVT));
Tmp2 = DAG.getNode(ISD::SRL, dl, VT, Op, DAG.getConstant(40, SHVT));
Tmp1 = DAG.getNode(ISD::SRL, dl, VT, Op, DAG.getConstant(56, SHVT));
Tmp7 = DAG.getNode(ISD::AND, dl, VT, Tmp7, DAG.getConstant(255ULL<<48, VT));
Tmp6 = DAG.getNode(ISD::AND, dl, VT, Tmp6, DAG.getConstant(255ULL<<40, VT));
Tmp5 = DAG.getNode(ISD::AND, dl, VT, Tmp5, DAG.getConstant(255ULL<<32, VT));
Tmp4 = DAG.getNode(ISD::AND, dl, VT, Tmp4, DAG.getConstant(255ULL<<24, VT));
Tmp3 = DAG.getNode(ISD::AND, dl, VT, Tmp3, DAG.getConstant(255ULL<<16, VT));
Tmp2 = DAG.getNode(ISD::AND, dl, VT, Tmp2, DAG.getConstant(255ULL<<8 , VT));
Tmp8 = DAG.getNode(ISD::OR, dl, VT, Tmp8, Tmp7);
Tmp6 = DAG.getNode(ISD::OR, dl, VT, Tmp6, Tmp5);
Tmp4 = DAG.getNode(ISD::OR, dl, VT, Tmp4, Tmp3);
Tmp2 = DAG.getNode(ISD::OR, dl, VT, Tmp2, Tmp1);
Tmp8 = DAG.getNode(ISD::OR, dl, VT, Tmp8, Tmp6);
Tmp4 = DAG.getNode(ISD::OR, dl, VT, Tmp4, Tmp2);
return DAG.getNode(ISD::OR, dl, VT, Tmp8, Tmp4);
}
}
/// ExpandBitCount - Expand the specified bitcount instruction into operations.
///
SDValue SelectionDAGLegalize::ExpandBitCount(unsigned Opc, SDValue Op,
DebugLoc dl) {
switch (Opc) {
default: llvm_unreachable("Cannot expand this yet!");
case ISD::CTPOP: {
static const uint64_t mask[6] = {
0x5555555555555555ULL, 0x3333333333333333ULL,
0x0F0F0F0F0F0F0F0FULL, 0x00FF00FF00FF00FFULL,
0x0000FFFF0000FFFFULL, 0x00000000FFFFFFFFULL
};
MVT VT = Op.getValueType();
MVT ShVT = TLI.getShiftAmountTy();
unsigned len = VT.getSizeInBits();
for (unsigned i = 0; (1U << i) <= (len / 2); ++i) {
//x = (x & mask[i][len/8]) + (x >> (1 << i) & mask[i][len/8])
unsigned EltSize = VT.isVector() ?
VT.getVectorElementType().getSizeInBits() : len;
SDValue Tmp2 = DAG.getConstant(APInt(EltSize, mask[i]), VT);
SDValue Tmp3 = DAG.getConstant(1ULL << i, ShVT);
Op = DAG.getNode(ISD::ADD, dl, VT,
DAG.getNode(ISD::AND, dl, VT, Op, Tmp2),
DAG.getNode(ISD::AND, dl, VT,
DAG.getNode(ISD::SRL, dl, VT, Op, Tmp3),
Tmp2));
}
return Op;
}
case ISD::CTLZ: {
// for now, we do this:
// x = x | (x >> 1);
// x = x | (x >> 2);
// ...
// x = x | (x >>16);
// x = x | (x >>32); // for 64-bit input
// return popcount(~x);
//
// but see also: http://www.hackersdelight.org/HDcode/nlz.cc
MVT VT = Op.getValueType();
MVT ShVT = TLI.getShiftAmountTy();
unsigned len = VT.getSizeInBits();
for (unsigned i = 0; (1U << i) <= (len / 2); ++i) {
SDValue Tmp3 = DAG.getConstant(1ULL << i, ShVT);
Op = DAG.getNode(ISD::OR, dl, VT, Op,
DAG.getNode(ISD::SRL, dl, VT, Op, Tmp3));
}
Op = DAG.getNOT(dl, Op, VT);
return DAG.getNode(ISD::CTPOP, dl, VT, Op);
}
case ISD::CTTZ: {
// for now, we use: { return popcount(~x & (x - 1)); }
// unless the target has ctlz but not ctpop, in which case we use:
// { return 32 - nlz(~x & (x-1)); }
// see also http://www.hackersdelight.org/HDcode/ntz.cc
MVT VT = Op.getValueType();
SDValue Tmp3 = DAG.getNode(ISD::AND, dl, VT,
DAG.getNOT(dl, Op, VT),
DAG.getNode(ISD::SUB, dl, VT, Op,
DAG.getConstant(1, VT)));
// If ISD::CTLZ is legal and CTPOP isn't, then do that instead.
if (!TLI.isOperationLegalOrCustom(ISD::CTPOP, VT) &&
TLI.isOperationLegalOrCustom(ISD::CTLZ, VT))
return DAG.getNode(ISD::SUB, dl, VT,
DAG.getConstant(VT.getSizeInBits(), VT),
DAG.getNode(ISD::CTLZ, dl, VT, Tmp3));
return DAG.getNode(ISD::CTPOP, dl, VT, Tmp3);
}
}
}
void SelectionDAGLegalize::ExpandNode(SDNode *Node,
SmallVectorImpl<SDValue> &Results) {
DebugLoc dl = Node->getDebugLoc();
SDValue Tmp1, Tmp2, Tmp3, Tmp4;
switch (Node->getOpcode()) {
case ISD::CTPOP:
case ISD::CTLZ:
case ISD::CTTZ:
Tmp1 = ExpandBitCount(Node->getOpcode(), Node->getOperand(0), dl);
Results.push_back(Tmp1);
break;
case ISD::BSWAP:
Results.push_back(ExpandBSWAP(Node->getOperand(0), dl));
break;
case ISD::FRAMEADDR:
case ISD::RETURNADDR:
case ISD::FRAME_TO_ARGS_OFFSET:
Results.push_back(DAG.getConstant(0, Node->getValueType(0)));
break;
case ISD::FLT_ROUNDS_:
Results.push_back(DAG.getConstant(1, Node->getValueType(0)));
break;
case ISD::EH_RETURN:
case ISD::DECLARE:
case ISD::DBG_LABEL:
case ISD::EH_LABEL:
case ISD::PREFETCH:
case ISD::MEMBARRIER:
case ISD::VAEND:
Results.push_back(Node->getOperand(0));
break;
case ISD::DBG_STOPPOINT:
Results.push_back(ExpandDBG_STOPPOINT(Node));
break;
case ISD::DYNAMIC_STACKALLOC:
ExpandDYNAMIC_STACKALLOC(Node, Results);
break;
case ISD::MERGE_VALUES:
for (unsigned i = 0; i < Node->getNumValues(); i++)
Results.push_back(Node->getOperand(i));
break;
case ISD::UNDEF: {
MVT VT = Node->getValueType(0);
if (VT.isInteger())
Results.push_back(DAG.getConstant(0, VT));
else if (VT.isFloatingPoint())
Results.push_back(DAG.getConstantFP(0, VT));
else
llvm_unreachable("Unknown value type!");
break;
}
case ISD::TRAP: {
// If this operation is not supported, lower it to 'abort()' call
TargetLowering::ArgListTy Args;
std::pair<SDValue, SDValue> CallResult =
TLI.LowerCallTo(Node->getOperand(0), Type::VoidTy,
false, false, false, false, 0, CallingConv::C, false,
DAG.getExternalSymbol("abort", TLI.getPointerTy()),
Args, DAG, dl);
Results.push_back(CallResult.second);
break;
}
case ISD::FP_ROUND:
case ISD::BIT_CONVERT:
Tmp1 = EmitStackConvert(Node->getOperand(0), Node->getValueType(0),
Node->getValueType(0), dl);
Results.push_back(Tmp1);
break;
case ISD::FP_EXTEND:
Tmp1 = EmitStackConvert(Node->getOperand(0),
Node->getOperand(0).getValueType(),
Node->getValueType(0), dl);
Results.push_back(Tmp1);
break;
case ISD::SIGN_EXTEND_INREG: {
// NOTE: we could fall back on load/store here too for targets without
// SAR. However, it is doubtful that any exist.
MVT ExtraVT = cast<VTSDNode>(Node->getOperand(1))->getVT();
unsigned BitsDiff = Node->getValueType(0).getSizeInBits() -
ExtraVT.getSizeInBits();
SDValue ShiftCst = DAG.getConstant(BitsDiff, TLI.getShiftAmountTy());
Tmp1 = DAG.getNode(ISD::SHL, dl, Node->getValueType(0),
Node->getOperand(0), ShiftCst);
Tmp1 = DAG.getNode(ISD::SRA, dl, Node->getValueType(0), Tmp1, ShiftCst);
Results.push_back(Tmp1);
break;
}
case ISD::FP_ROUND_INREG: {
// The only way we can lower this is to turn it into a TRUNCSTORE,
// EXTLOAD pair, targetting a temporary location (a stack slot).
// NOTE: there is a choice here between constantly creating new stack
// slots and always reusing the same one. We currently always create
// new ones, as reuse may inhibit scheduling.
MVT ExtraVT = cast<VTSDNode>(Node->getOperand(1))->getVT();
Tmp1 = EmitStackConvert(Node->getOperand(0), ExtraVT,
Node->getValueType(0), dl);
Results.push_back(Tmp1);
break;
}
case ISD::SINT_TO_FP:
case ISD::UINT_TO_FP:
Tmp1 = ExpandLegalINT_TO_FP(Node->getOpcode() == ISD::SINT_TO_FP,
Node->getOperand(0), Node->getValueType(0), dl);
Results.push_back(Tmp1);
break;
case ISD::FP_TO_UINT: {
SDValue True, False;
MVT VT = Node->getOperand(0).getValueType();
MVT NVT = Node->getValueType(0);
const uint64_t zero[] = {0, 0};
APFloat apf = APFloat(APInt(VT.getSizeInBits(), 2, zero));
APInt x = APInt::getSignBit(NVT.getSizeInBits());
(void)apf.convertFromAPInt(x, false, APFloat::rmNearestTiesToEven);
Tmp1 = DAG.getConstantFP(apf, VT);
Tmp2 = DAG.getSetCC(dl, TLI.getSetCCResultType(VT),
Node->getOperand(0),
Tmp1, ISD::SETLT);
True = DAG.getNode(ISD::FP_TO_SINT, dl, NVT, Node->getOperand(0));
False = DAG.getNode(ISD::FP_TO_SINT, dl, NVT,
DAG.getNode(ISD::FSUB, dl, VT,
Node->getOperand(0), Tmp1));
False = DAG.getNode(ISD::XOR, dl, NVT, False,
DAG.getConstant(x, NVT));
Tmp1 = DAG.getNode(ISD::SELECT, dl, NVT, Tmp2, True, False);
Results.push_back(Tmp1);
break;
}
case ISD::VAARG: {
const Value *V = cast<SrcValueSDNode>(Node->getOperand(2))->getValue();
MVT VT = Node->getValueType(0);
Tmp1 = Node->getOperand(0);
Tmp2 = Node->getOperand(1);
SDValue VAList = DAG.getLoad(TLI.getPointerTy(), dl, Tmp1, Tmp2, V, 0);
// Increment the pointer, VAList, to the next vaarg
Tmp3 = DAG.getNode(ISD::ADD, dl, TLI.getPointerTy(), VAList,
DAG.getConstant(TLI.getTargetData()->
getTypeAllocSize(VT.getTypeForMVT(
*DAG.getContext())),
TLI.getPointerTy()));
// Store the incremented VAList to the legalized pointer
Tmp3 = DAG.getStore(VAList.getValue(1), dl, Tmp3, Tmp2, V, 0);
// Load the actual argument out of the pointer VAList
Results.push_back(DAG.getLoad(VT, dl, Tmp3, VAList, NULL, 0));
Results.push_back(Results[0].getValue(1));
break;
}
case ISD::VACOPY: {
// This defaults to loading a pointer from the input and storing it to the
// output, returning the chain.
const Value *VD = cast<SrcValueSDNode>(Node->getOperand(3))->getValue();
const Value *VS = cast<SrcValueSDNode>(Node->getOperand(4))->getValue();
Tmp1 = DAG.getLoad(TLI.getPointerTy(), dl, Node->getOperand(0),
Node->getOperand(2), VS, 0);
Tmp1 = DAG.getStore(Tmp1.getValue(1), dl, Tmp1, Node->getOperand(1), VD, 0);
Results.push_back(Tmp1);
break;
}
case ISD::EXTRACT_VECTOR_ELT:
if (Node->getOperand(0).getValueType().getVectorNumElements() == 1)
// This must be an access of the only element. Return it.
Tmp1 = DAG.getNode(ISD::BIT_CONVERT, dl, Node->getValueType(0),
Node->getOperand(0));
else
Tmp1 = ExpandExtractFromVectorThroughStack(SDValue(Node, 0));
Results.push_back(Tmp1);
break;
case ISD::EXTRACT_SUBVECTOR:
Results.push_back(ExpandExtractFromVectorThroughStack(SDValue(Node, 0)));
break;
case ISD::CONCAT_VECTORS: {
Results.push_back(ExpandVectorBuildThroughStack(Node));
break;
}
case ISD::SCALAR_TO_VECTOR:
Results.push_back(ExpandSCALAR_TO_VECTOR(Node));
break;
case ISD::INSERT_VECTOR_ELT:
Results.push_back(ExpandINSERT_VECTOR_ELT(Node->getOperand(0),
Node->getOperand(1),
Node->getOperand(2), dl));
break;
case ISD::VECTOR_SHUFFLE: {
SmallVector<int, 8> Mask;
cast<ShuffleVectorSDNode>(Node)->getMask(Mask);
MVT VT = Node->getValueType(0);
MVT EltVT = VT.getVectorElementType();
unsigned NumElems = VT.getVectorNumElements();
SmallVector<SDValue, 8> Ops;
for (unsigned i = 0; i != NumElems; ++i) {
if (Mask[i] < 0) {
Ops.push_back(DAG.getUNDEF(EltVT));
continue;
}
unsigned Idx = Mask[i];
if (Idx < NumElems)
Ops.push_back(DAG.getNode(ISD::EXTRACT_VECTOR_ELT, dl, EltVT,
Node->getOperand(0),
DAG.getIntPtrConstant(Idx)));
else
Ops.push_back(DAG.getNode(ISD::EXTRACT_VECTOR_ELT, dl, EltVT,
Node->getOperand(1),
DAG.getIntPtrConstant(Idx - NumElems)));
}
Tmp1 = DAG.getNode(ISD::BUILD_VECTOR, dl, VT, &Ops[0], Ops.size());
Results.push_back(Tmp1);
break;
}
case ISD::EXTRACT_ELEMENT: {
MVT OpTy = Node->getOperand(0).getValueType();
if (cast<ConstantSDNode>(Node->getOperand(1))->getZExtValue()) {
// 1 -> Hi
Tmp1 = DAG.getNode(ISD::SRL, dl, OpTy, Node->getOperand(0),
DAG.getConstant(OpTy.getSizeInBits()/2,
TLI.getShiftAmountTy()));
Tmp1 = DAG.getNode(ISD::TRUNCATE, dl, Node->getValueType(0), Tmp1);
} else {
// 0 -> Lo
Tmp1 = DAG.getNode(ISD::TRUNCATE, dl, Node->getValueType(0),
Node->getOperand(0));
}
Results.push_back(Tmp1);
break;
}
case ISD::STACKSAVE:
// Expand to CopyFromReg if the target set
// StackPointerRegisterToSaveRestore.
if (unsigned SP = TLI.getStackPointerRegisterToSaveRestore()) {
Results.push_back(DAG.getCopyFromReg(Node->getOperand(0), dl, SP,
Node->getValueType(0)));
Results.push_back(Results[0].getValue(1));
} else {
Results.push_back(DAG.getUNDEF(Node->getValueType(0)));
Results.push_back(Node->getOperand(0));
}
break;
case ISD::STACKRESTORE:
// Expand to CopyToReg if the target set
// StackPointerRegisterToSaveRestore.
if (unsigned SP = TLI.getStackPointerRegisterToSaveRestore()) {
Results.push_back(DAG.getCopyToReg(Node->getOperand(0), dl, SP,
Node->getOperand(1)));
} else {
Results.push_back(Node->getOperand(0));
}
break;
case ISD::FCOPYSIGN:
Results.push_back(ExpandFCOPYSIGN(Node));
break;
case ISD::FNEG:
// Expand Y = FNEG(X) -> Y = SUB -0.0, X
Tmp1 = DAG.getConstantFP(-0.0, Node->getValueType(0));
Tmp1 = DAG.getNode(ISD::FSUB, dl, Node->getValueType(0), Tmp1,
Node->getOperand(0));
Results.push_back(Tmp1);
break;
case ISD::FABS: {
// Expand Y = FABS(X) -> Y = (X >u 0.0) ? X : fneg(X).
MVT VT = Node->getValueType(0);
Tmp1 = Node->getOperand(0);
Tmp2 = DAG.getConstantFP(0.0, VT);
Tmp2 = DAG.getSetCC(dl, TLI.getSetCCResultType(Tmp1.getValueType()),
Tmp1, Tmp2, ISD::SETUGT);
Tmp3 = DAG.getNode(ISD::FNEG, dl, VT, Tmp1);
Tmp1 = DAG.getNode(ISD::SELECT, dl, VT, Tmp2, Tmp1, Tmp3);
Results.push_back(Tmp1);
break;
}
case ISD::FSQRT:
Results.push_back(ExpandFPLibCall(Node, RTLIB::SQRT_F32, RTLIB::SQRT_F64,
RTLIB::SQRT_F80, RTLIB::SQRT_PPCF128));
break;
case ISD::FSIN:
Results.push_back(ExpandFPLibCall(Node, RTLIB::SIN_F32, RTLIB::SIN_F64,
RTLIB::SIN_F80, RTLIB::SIN_PPCF128));
break;
case ISD::FCOS:
Results.push_back(ExpandFPLibCall(Node, RTLIB::COS_F32, RTLIB::COS_F64,
RTLIB::COS_F80, RTLIB::COS_PPCF128));
break;
case ISD::FLOG:
Results.push_back(ExpandFPLibCall(Node, RTLIB::LOG_F32, RTLIB::LOG_F64,
RTLIB::LOG_F80, RTLIB::LOG_PPCF128));
break;
case ISD::FLOG2:
Results.push_back(ExpandFPLibCall(Node, RTLIB::LOG2_F32, RTLIB::LOG2_F64,
RTLIB::LOG2_F80, RTLIB::LOG2_PPCF128));
break;
case ISD::FLOG10:
Results.push_back(ExpandFPLibCall(Node, RTLIB::LOG10_F32, RTLIB::LOG10_F64,
RTLIB::LOG10_F80, RTLIB::LOG10_PPCF128));
break;
case ISD::FEXP:
Results.push_back(ExpandFPLibCall(Node, RTLIB::EXP_F32, RTLIB::EXP_F64,
RTLIB::EXP_F80, RTLIB::EXP_PPCF128));
break;
case ISD::FEXP2:
Results.push_back(ExpandFPLibCall(Node, RTLIB::EXP2_F32, RTLIB::EXP2_F64,
RTLIB::EXP2_F80, RTLIB::EXP2_PPCF128));
break;
case ISD::FTRUNC:
Results.push_back(ExpandFPLibCall(Node, RTLIB::TRUNC_F32, RTLIB::TRUNC_F64,
RTLIB::TRUNC_F80, RTLIB::TRUNC_PPCF128));
break;
case ISD::FFLOOR:
Results.push_back(ExpandFPLibCall(Node, RTLIB::FLOOR_F32, RTLIB::FLOOR_F64,
RTLIB::FLOOR_F80, RTLIB::FLOOR_PPCF128));
break;
case ISD::FCEIL:
Results.push_back(ExpandFPLibCall(Node, RTLIB::CEIL_F32, RTLIB::CEIL_F64,
RTLIB::CEIL_F80, RTLIB::CEIL_PPCF128));
break;
case ISD::FRINT:
Results.push_back(ExpandFPLibCall(Node, RTLIB::RINT_F32, RTLIB::RINT_F64,
RTLIB::RINT_F80, RTLIB::RINT_PPCF128));
break;
case ISD::FNEARBYINT:
Results.push_back(ExpandFPLibCall(Node, RTLIB::NEARBYINT_F32,
RTLIB::NEARBYINT_F64,
RTLIB::NEARBYINT_F80,
RTLIB::NEARBYINT_PPCF128));
break;
case ISD::FPOWI:
Results.push_back(ExpandFPLibCall(Node, RTLIB::POWI_F32, RTLIB::POWI_F64,
RTLIB::POWI_F80, RTLIB::POWI_PPCF128));
break;
case ISD::FPOW:
Results.push_back(ExpandFPLibCall(Node, RTLIB::POW_F32, RTLIB::POW_F64,
RTLIB::POW_F80, RTLIB::POW_PPCF128));
break;
case ISD::FDIV:
Results.push_back(ExpandFPLibCall(Node, RTLIB::DIV_F32, RTLIB::DIV_F64,
RTLIB::DIV_F80, RTLIB::DIV_PPCF128));
break;
case ISD::FREM:
Results.push_back(ExpandFPLibCall(Node, RTLIB::REM_F32, RTLIB::REM_F64,
RTLIB::REM_F80, RTLIB::REM_PPCF128));
break;
case ISD::ConstantFP: {
ConstantFPSDNode *CFP = cast<ConstantFPSDNode>(Node);
// Check to see if this FP immediate is already legal.
bool isLegal = false;
for (TargetLowering::legal_fpimm_iterator I = TLI.legal_fpimm_begin(),
E = TLI.legal_fpimm_end(); I != E; ++I) {
if (CFP->isExactlyValue(*I)) {
isLegal = true;
break;
}
}
// If this is a legal constant, turn it into a TargetConstantFP node.
if (isLegal)
Results.push_back(SDValue(Node, 0));
else
Results.push_back(ExpandConstantFP(CFP, true, DAG, TLI));
break;
}
case ISD::EHSELECTION: {
unsigned Reg = TLI.getExceptionSelectorRegister();
assert(Reg && "Can't expand to unknown register!");
Results.push_back(DAG.getCopyFromReg(Node->getOperand(1), dl, Reg,
Node->getValueType(0)));
Results.push_back(Results[0].getValue(1));
break;
}
case ISD::EXCEPTIONADDR: {
unsigned Reg = TLI.getExceptionAddressRegister();
assert(Reg && "Can't expand to unknown register!");
Results.push_back(DAG.getCopyFromReg(Node->getOperand(0), dl, Reg,
Node->getValueType(0)));
Results.push_back(Results[0].getValue(1));
break;
}
case ISD::SUB: {
MVT VT = Node->getValueType(0);
assert(TLI.isOperationLegalOrCustom(ISD::ADD, VT) &&
TLI.isOperationLegalOrCustom(ISD::XOR, VT) &&
"Don't know how to expand this subtraction!");
Tmp1 = DAG.getNode(ISD::XOR, dl, VT, Node->getOperand(1),
DAG.getConstant(APInt::getAllOnesValue(VT.getSizeInBits()), VT));
Tmp1 = DAG.getNode(ISD::ADD, dl, VT, Tmp2, DAG.getConstant(1, VT));
Results.push_back(DAG.getNode(ISD::ADD, dl, VT, Node->getOperand(0), Tmp1));
break;
}
case ISD::UREM:
case ISD::SREM: {
MVT VT = Node->getValueType(0);
SDVTList VTs = DAG.getVTList(VT, VT);
bool isSigned = Node->getOpcode() == ISD::SREM;
unsigned DivOpc = isSigned ? ISD::SDIV : ISD::UDIV;
unsigned DivRemOpc = isSigned ? ISD::SDIVREM : ISD::UDIVREM;
Tmp2 = Node->getOperand(0);
Tmp3 = Node->getOperand(1);
if (TLI.isOperationLegalOrCustom(DivRemOpc, VT)) {
Tmp1 = DAG.getNode(DivRemOpc, dl, VTs, Tmp2, Tmp3).getValue(1);
} else if (TLI.isOperationLegalOrCustom(DivOpc, VT)) {
// X % Y -> X-X/Y*Y
Tmp1 = DAG.getNode(DivOpc, dl, VT, Tmp2, Tmp3);
Tmp1 = DAG.getNode(ISD::MUL, dl, VT, Tmp1, Tmp3);
Tmp1 = DAG.getNode(ISD::SUB, dl, VT, Tmp2, Tmp1);
} else if (isSigned) {
Tmp1 = ExpandIntLibCall(Node, true, RTLIB::SREM_I16, RTLIB::SREM_I32,
RTLIB::SREM_I64, RTLIB::SREM_I128);
} else {
Tmp1 = ExpandIntLibCall(Node, false, RTLIB::UREM_I16, RTLIB::UREM_I32,
RTLIB::UREM_I64, RTLIB::UREM_I128);
}
Results.push_back(Tmp1);
break;
}
case ISD::UDIV:
case ISD::SDIV: {
bool isSigned = Node->getOpcode() == ISD::SDIV;
unsigned DivRemOpc = isSigned ? ISD::SDIVREM : ISD::UDIVREM;
MVT VT = Node->getValueType(0);
SDVTList VTs = DAG.getVTList(VT, VT);
if (TLI.isOperationLegalOrCustom(DivRemOpc, VT))
Tmp1 = DAG.getNode(DivRemOpc, dl, VTs, Node->getOperand(0),
Node->getOperand(1));
else if (isSigned)
Tmp1 = ExpandIntLibCall(Node, true, RTLIB::SDIV_I16, RTLIB::SDIV_I32,
RTLIB::SDIV_I64, RTLIB::SDIV_I128);
else
Tmp1 = ExpandIntLibCall(Node, false, RTLIB::UDIV_I16, RTLIB::UDIV_I32,
RTLIB::UDIV_I64, RTLIB::UDIV_I128);
Results.push_back(Tmp1);
break;
}
case ISD::MULHU:
case ISD::MULHS: {
unsigned ExpandOpcode = Node->getOpcode() == ISD::MULHU ? ISD::UMUL_LOHI :
ISD::SMUL_LOHI;
MVT VT = Node->getValueType(0);
SDVTList VTs = DAG.getVTList(VT, VT);
assert(TLI.isOperationLegalOrCustom(ExpandOpcode, VT) &&
"If this wasn't legal, it shouldn't have been created!");
Tmp1 = DAG.getNode(ExpandOpcode, dl, VTs, Node->getOperand(0),
Node->getOperand(1));
Results.push_back(Tmp1.getValue(1));
break;
}
case ISD::MUL: {
MVT VT = Node->getValueType(0);
SDVTList VTs = DAG.getVTList(VT, VT);
// See if multiply or divide can be lowered using two-result operations.
// We just need the low half of the multiply; try both the signed
// and unsigned forms. If the target supports both SMUL_LOHI and
// UMUL_LOHI, form a preference by checking which forms of plain
// MULH it supports.
bool HasSMUL_LOHI = TLI.isOperationLegalOrCustom(ISD::SMUL_LOHI, VT);
bool HasUMUL_LOHI = TLI.isOperationLegalOrCustom(ISD::UMUL_LOHI, VT);
bool HasMULHS = TLI.isOperationLegalOrCustom(ISD::MULHS, VT);
bool HasMULHU = TLI.isOperationLegalOrCustom(ISD::MULHU, VT);
unsigned OpToUse = 0;
if (HasSMUL_LOHI && !HasMULHS) {
OpToUse = ISD::SMUL_LOHI;
} else if (HasUMUL_LOHI && !HasMULHU) {
OpToUse = ISD::UMUL_LOHI;
} else if (HasSMUL_LOHI) {
OpToUse = ISD::SMUL_LOHI;
} else if (HasUMUL_LOHI) {
OpToUse = ISD::UMUL_LOHI;
}
if (OpToUse) {
Results.push_back(DAG.getNode(OpToUse, dl, VTs, Node->getOperand(0),
Node->getOperand(1)));
break;
}
Tmp1 = ExpandIntLibCall(Node, false, RTLIB::MUL_I16, RTLIB::MUL_I32,
RTLIB::MUL_I64, RTLIB::MUL_I128);
Results.push_back(Tmp1);
break;
}
case ISD::SADDO:
case ISD::SSUBO: {
SDValue LHS = Node->getOperand(0);
SDValue RHS = Node->getOperand(1);
SDValue Sum = DAG.getNode(Node->getOpcode() == ISD::SADDO ?
ISD::ADD : ISD::SUB, dl, LHS.getValueType(),
LHS, RHS);
Results.push_back(Sum);
MVT OType = Node->getValueType(1);
SDValue Zero = DAG.getConstant(0, LHS.getValueType());
// LHSSign -> LHS >= 0
// RHSSign -> RHS >= 0
// SumSign -> Sum >= 0
//
// Add:
// Overflow -> (LHSSign == RHSSign) && (LHSSign != SumSign)
// Sub:
// Overflow -> (LHSSign != RHSSign) && (LHSSign != SumSign)
//
SDValue LHSSign = DAG.getSetCC(dl, OType, LHS, Zero, ISD::SETGE);
SDValue RHSSign = DAG.getSetCC(dl, OType, RHS, Zero, ISD::SETGE);
SDValue SignsMatch = DAG.getSetCC(dl, OType, LHSSign, RHSSign,
Node->getOpcode() == ISD::SADDO ?
ISD::SETEQ : ISD::SETNE);
SDValue SumSign = DAG.getSetCC(dl, OType, Sum, Zero, ISD::SETGE);
SDValue SumSignNE = DAG.getSetCC(dl, OType, LHSSign, SumSign, ISD::SETNE);
SDValue Cmp = DAG.getNode(ISD::AND, dl, OType, SignsMatch, SumSignNE);
Results.push_back(Cmp);
break;
}
case ISD::UADDO:
case ISD::USUBO: {
SDValue LHS = Node->getOperand(0);
SDValue RHS = Node->getOperand(1);
SDValue Sum = DAG.getNode(Node->getOpcode() == ISD::UADDO ?
ISD::ADD : ISD::SUB, dl, LHS.getValueType(),
LHS, RHS);
Results.push_back(Sum);
Results.push_back(DAG.getSetCC(dl, Node->getValueType(1), Sum, LHS,
Node->getOpcode () == ISD::UADDO ?
ISD::SETULT : ISD::SETUGT));
break;
}
case ISD::UMULO:
case ISD::SMULO: {
MVT VT = Node->getValueType(0);
SDValue LHS = Node->getOperand(0);
SDValue RHS = Node->getOperand(1);
SDValue BottomHalf;
SDValue TopHalf;
static unsigned Ops[2][3] =
{ { ISD::MULHU, ISD::UMUL_LOHI, ISD::ZERO_EXTEND },
{ ISD::MULHS, ISD::SMUL_LOHI, ISD::SIGN_EXTEND }};
bool isSigned = Node->getOpcode() == ISD::SMULO;
if (TLI.isOperationLegalOrCustom(Ops[isSigned][0], VT)) {
BottomHalf = DAG.getNode(ISD::MUL, dl, VT, LHS, RHS);
TopHalf = DAG.getNode(Ops[isSigned][0], dl, VT, LHS, RHS);
} else if (TLI.isOperationLegalOrCustom(Ops[isSigned][1], VT)) {
BottomHalf = DAG.getNode(Ops[isSigned][1], dl, DAG.getVTList(VT, VT), LHS,
RHS);
TopHalf = BottomHalf.getValue(1);
} else if (TLI.isTypeLegal(MVT::getIntegerVT(VT.getSizeInBits() * 2))) {
MVT WideVT = MVT::getIntegerVT(VT.getSizeInBits() * 2);
LHS = DAG.getNode(Ops[isSigned][2], dl, WideVT, LHS);
RHS = DAG.getNode(Ops[isSigned][2], dl, WideVT, RHS);
Tmp1 = DAG.getNode(ISD::MUL, dl, WideVT, LHS, RHS);
BottomHalf = DAG.getNode(ISD::EXTRACT_ELEMENT, dl, VT, Tmp1,
DAG.getIntPtrConstant(0));
TopHalf = DAG.getNode(ISD::EXTRACT_ELEMENT, dl, VT, Tmp1,
DAG.getIntPtrConstant(1));
} else {
// FIXME: We should be able to fall back to a libcall with an illegal
// type in some cases cases.
// Also, we can fall back to a division in some cases, but that's a big
// performance hit in the general case.
llvm_unreachable("Don't know how to expand this operation yet!");
}
if (isSigned) {
Tmp1 = DAG.getConstant(VT.getSizeInBits() - 1, TLI.getShiftAmountTy());
Tmp1 = DAG.getNode(ISD::SRA, dl, VT, BottomHalf, Tmp1);
TopHalf = DAG.getSetCC(dl, TLI.getSetCCResultType(VT), TopHalf, Tmp1,
ISD::SETNE);
} else {
TopHalf = DAG.getSetCC(dl, TLI.getSetCCResultType(VT), TopHalf,
DAG.getConstant(0, VT), ISD::SETNE);
}
Results.push_back(BottomHalf);
Results.push_back(TopHalf);
break;
}
case ISD::BUILD_PAIR: {
MVT PairTy = Node->getValueType(0);
Tmp1 = DAG.getNode(ISD::ZERO_EXTEND, dl, PairTy, Node->getOperand(0));
Tmp2 = DAG.getNode(ISD::ANY_EXTEND, dl, PairTy, Node->getOperand(1));
Tmp2 = DAG.getNode(ISD::SHL, dl, PairTy, Tmp2,
DAG.getConstant(PairTy.getSizeInBits()/2,
TLI.getShiftAmountTy()));
Results.push_back(DAG.getNode(ISD::OR, dl, PairTy, Tmp1, Tmp2));
break;
}
case ISD::SELECT:
Tmp1 = Node->getOperand(0);
Tmp2 = Node->getOperand(1);
Tmp3 = Node->getOperand(2);
if (Tmp1.getOpcode() == ISD::SETCC) {
Tmp1 = DAG.getSelectCC(dl, Tmp1.getOperand(0), Tmp1.getOperand(1),
Tmp2, Tmp3,
cast<CondCodeSDNode>(Tmp1.getOperand(2))->get());
} else {
Tmp1 = DAG.getSelectCC(dl, Tmp1,
DAG.getConstant(0, Tmp1.getValueType()),
Tmp2, Tmp3, ISD::SETNE);
}
Results.push_back(Tmp1);
break;
case ISD::BR_JT: {
SDValue Chain = Node->getOperand(0);
SDValue Table = Node->getOperand(1);
SDValue Index = Node->getOperand(2);
MVT PTy = TLI.getPointerTy();
MachineFunction &MF = DAG.getMachineFunction();
unsigned EntrySize = MF.getJumpTableInfo()->getEntrySize();
Index= DAG.getNode(ISD::MUL, dl, PTy,
Index, DAG.getConstant(EntrySize, PTy));
SDValue Addr = DAG.getNode(ISD::ADD, dl, PTy, Index, Table);
MVT MemVT = MVT::getIntegerVT(EntrySize * 8);
SDValue LD = DAG.getExtLoad(ISD::SEXTLOAD, dl, PTy, Chain, Addr,
PseudoSourceValue::getJumpTable(), 0, MemVT);
Addr = LD;
if (TLI.getTargetMachine().getRelocationModel() == Reloc::PIC_) {
// For PIC, the sequence is:
// BRIND(load(Jumptable + index) + RelocBase)
// RelocBase can be JumpTable, GOT or some sort of global base.
Addr = DAG.getNode(ISD::ADD, dl, PTy, Addr,
TLI.getPICJumpTableRelocBase(Table, DAG));
}
Tmp1 = DAG.getNode(ISD::BRIND, dl, MVT::Other, LD.getValue(1), Addr);
Results.push_back(Tmp1);
break;
}
case ISD::BRCOND:
// Expand brcond's setcc into its constituent parts and create a BR_CC
// Node.
Tmp1 = Node->getOperand(0);
Tmp2 = Node->getOperand(1);
if (Tmp2.getOpcode() == ISD::SETCC) {
Tmp1 = DAG.getNode(ISD::BR_CC, dl, MVT::Other,
Tmp1, Tmp2.getOperand(2),
Tmp2.getOperand(0), Tmp2.getOperand(1),
Node->getOperand(2));
} else {
Tmp1 = DAG.getNode(ISD::BR_CC, dl, MVT::Other, Tmp1,
DAG.getCondCode(ISD::SETNE), Tmp2,
DAG.getConstant(0, Tmp2.getValueType()),
Node->getOperand(2));
}
Results.push_back(Tmp1);
break;
case ISD::SETCC: {
Tmp1 = Node->getOperand(0);
Tmp2 = Node->getOperand(1);
Tmp3 = Node->getOperand(2);
LegalizeSetCCCondCode(Node->getValueType(0), Tmp1, Tmp2, Tmp3, dl);
// If we expanded the SETCC into an AND/OR, return the new node
if (Tmp2.getNode() == 0) {
Results.push_back(Tmp1);
break;
}
// Otherwise, SETCC for the given comparison type must be completely
// illegal; expand it into a SELECT_CC.
MVT VT = Node->getValueType(0);
Tmp1 = DAG.getNode(ISD::SELECT_CC, dl, VT, Tmp1, Tmp2,
DAG.getConstant(1, VT), DAG.getConstant(0, VT), Tmp3);
Results.push_back(Tmp1);
break;
}
case ISD::SELECT_CC: {
Tmp1 = Node->getOperand(0); // LHS
Tmp2 = Node->getOperand(1); // RHS
Tmp3 = Node->getOperand(2); // True
Tmp4 = Node->getOperand(3); // False
SDValue CC = Node->getOperand(4);
LegalizeSetCCCondCode(TLI.getSetCCResultType(Tmp1.getValueType()),
Tmp1, Tmp2, CC, dl);
assert(!Tmp2.getNode() && "Can't legalize SELECT_CC with legal condition!");
Tmp2 = DAG.getConstant(0, Tmp1.getValueType());
CC = DAG.getCondCode(ISD::SETNE);
Tmp1 = DAG.getNode(ISD::SELECT_CC, dl, Node->getValueType(0), Tmp1, Tmp2,
Tmp3, Tmp4, CC);
Results.push_back(Tmp1);
break;
}
case ISD::BR_CC: {
Tmp1 = Node->getOperand(0); // Chain
Tmp2 = Node->getOperand(2); // LHS
Tmp3 = Node->getOperand(3); // RHS
Tmp4 = Node->getOperand(1); // CC
LegalizeSetCCCondCode(TLI.getSetCCResultType(Tmp2.getValueType()),
Tmp2, Tmp3, Tmp4, dl);
LastCALLSEQ_END = DAG.getEntryNode();
assert(!Tmp3.getNode() && "Can't legalize BR_CC with legal condition!");
Tmp3 = DAG.getConstant(0, Tmp2.getValueType());
Tmp4 = DAG.getCondCode(ISD::SETNE);
Tmp1 = DAG.getNode(ISD::BR_CC, dl, Node->getValueType(0), Tmp1, Tmp4, Tmp2,
Tmp3, Node->getOperand(4));
Results.push_back(Tmp1);
break;
}
case ISD::GLOBAL_OFFSET_TABLE:
case ISD::GlobalAddress:
case ISD::GlobalTLSAddress:
case ISD::ExternalSymbol:
case ISD::ConstantPool:
case ISD::JumpTable:
case ISD::INTRINSIC_W_CHAIN:
case ISD::INTRINSIC_WO_CHAIN:
case ISD::INTRINSIC_VOID:
// FIXME: Custom lowering for these operations shouldn't return null!
for (unsigned i = 0, e = Node->getNumValues(); i != e; ++i)
Results.push_back(SDValue(Node, i));
break;
}
}
void SelectionDAGLegalize::PromoteNode(SDNode *Node,
SmallVectorImpl<SDValue> &Results) {
MVT OVT = Node->getValueType(0);
if (Node->getOpcode() == ISD::UINT_TO_FP ||
Node->getOpcode() == ISD::SINT_TO_FP ||
Node->getOpcode() == ISD::SETCC) {
OVT = Node->getOperand(0).getValueType();
}
MVT NVT = TLI.getTypeToPromoteTo(Node->getOpcode(), OVT);
DebugLoc dl = Node->getDebugLoc();
SDValue Tmp1, Tmp2, Tmp3;
switch (Node->getOpcode()) {
case ISD::CTTZ:
case ISD::CTLZ:
case ISD::CTPOP:
// Zero extend the argument.
Tmp1 = DAG.getNode(ISD::ZERO_EXTEND, dl, NVT, Node->getOperand(0));
// Perform the larger operation.
Tmp1 = DAG.getNode(Node->getOpcode(), dl, NVT, Tmp1);
if (Node->getOpcode() == ISD::CTTZ) {
//if Tmp1 == sizeinbits(NVT) then Tmp1 = sizeinbits(Old VT)
Tmp2 = DAG.getSetCC(dl, TLI.getSetCCResultType(NVT),
Tmp1, DAG.getConstant(NVT.getSizeInBits(), NVT),
ISD::SETEQ);
Tmp1 = DAG.getNode(ISD::SELECT, dl, NVT, Tmp2,
DAG.getConstant(OVT.getSizeInBits(), NVT), Tmp1);
} else if (Node->getOpcode() == ISD::CTLZ) {
// Tmp1 = Tmp1 - (sizeinbits(NVT) - sizeinbits(Old VT))
Tmp1 = DAG.getNode(ISD::SUB, dl, NVT, Tmp1,
DAG.getConstant(NVT.getSizeInBits() -
OVT.getSizeInBits(), NVT));
}
Results.push_back(DAG.getNode(ISD::TRUNCATE, dl, OVT, Tmp1));
break;
case ISD::BSWAP: {
unsigned DiffBits = NVT.getSizeInBits() - OVT.getSizeInBits();
Tmp1 = DAG.getNode(ISD::ZERO_EXTEND, dl, NVT, Tmp1);
Tmp1 = DAG.getNode(ISD::BSWAP, dl, NVT, Tmp1);
Tmp1 = DAG.getNode(ISD::SRL, dl, NVT, Tmp1,
DAG.getConstant(DiffBits, TLI.getShiftAmountTy()));
Results.push_back(Tmp1);
break;
}
case ISD::FP_TO_UINT:
case ISD::FP_TO_SINT:
Tmp1 = PromoteLegalFP_TO_INT(Node->getOperand(0), Node->getValueType(0),
Node->getOpcode() == ISD::FP_TO_SINT, dl);
Results.push_back(Tmp1);
break;
case ISD::UINT_TO_FP:
case ISD::SINT_TO_FP:
Tmp1 = PromoteLegalINT_TO_FP(Node->getOperand(0), Node->getValueType(0),
Node->getOpcode() == ISD::SINT_TO_FP, dl);
Results.push_back(Tmp1);
break;
case ISD::AND:
case ISD::OR:
case ISD::XOR: {
unsigned ExtOp, TruncOp;
if (OVT.isVector()) {
ExtOp = ISD::BIT_CONVERT;
TruncOp = ISD::BIT_CONVERT;
} else if (OVT.isInteger()) {
ExtOp = ISD::ANY_EXTEND;
TruncOp = ISD::TRUNCATE;
} else {
llvm_report_error("Cannot promote logic operation");
}
// Promote each of the values to the new type.
Tmp1 = DAG.getNode(ExtOp, dl, NVT, Node->getOperand(0));
Tmp2 = DAG.getNode(ExtOp, dl, NVT, Node->getOperand(1));
// Perform the larger operation, then convert back
Tmp1 = DAG.getNode(Node->getOpcode(), dl, NVT, Tmp1, Tmp2);
Results.push_back(DAG.getNode(TruncOp, dl, OVT, Tmp1));
break;
}
case ISD::SELECT: {
unsigned ExtOp, TruncOp;
if (Node->getValueType(0).isVector()) {
ExtOp = ISD::BIT_CONVERT;
TruncOp = ISD::BIT_CONVERT;
} else if (Node->getValueType(0).isInteger()) {
ExtOp = ISD::ANY_EXTEND;
TruncOp = ISD::TRUNCATE;
} else {
ExtOp = ISD::FP_EXTEND;
TruncOp = ISD::FP_ROUND;
}
Tmp1 = Node->getOperand(0);
// Promote each of the values to the new type.
Tmp2 = DAG.getNode(ExtOp, dl, NVT, Node->getOperand(1));
Tmp3 = DAG.getNode(ExtOp, dl, NVT, Node->getOperand(2));
// Perform the larger operation, then round down.
Tmp1 = DAG.getNode(ISD::SELECT, dl, NVT, Tmp1, Tmp2, Tmp3);
if (TruncOp != ISD::FP_ROUND)
Tmp1 = DAG.getNode(TruncOp, dl, Node->getValueType(0), Tmp1);
else
Tmp1 = DAG.getNode(TruncOp, dl, Node->getValueType(0), Tmp1,
DAG.getIntPtrConstant(0));
Results.push_back(Tmp1);
break;
}
case ISD::VECTOR_SHUFFLE: {
SmallVector<int, 8> Mask;
cast<ShuffleVectorSDNode>(Node)->getMask(Mask);
// Cast the two input vectors.
Tmp1 = DAG.getNode(ISD::BIT_CONVERT, dl, NVT, Node->getOperand(0));
Tmp2 = DAG.getNode(ISD::BIT_CONVERT, dl, NVT, Node->getOperand(1));
// Convert the shuffle mask to the right # elements.
Tmp1 = ShuffleWithNarrowerEltType(NVT, OVT, dl, Tmp1, Tmp2, Mask);
Tmp1 = DAG.getNode(ISD::BIT_CONVERT, dl, OVT, Tmp1);
Results.push_back(Tmp1);
break;
}
case ISD::SETCC: {
if (NVT.isInteger())
llvm_unreachable("Cannot promote Legal Integer SETCC yet");
else {
Tmp1 = DAG.getNode(ISD::FP_EXTEND, dl, NVT, Node->getOperand(0));
Tmp2 = DAG.getNode(ISD::FP_EXTEND, dl, NVT, Node->getOperand(1));
}
Results.push_back(DAG.getNode(ISD::SETCC, dl, Node->getValueType(0),
Tmp1, Tmp2, Node->getOperand(2)));
break;
}
}
}
// SelectionDAG::Legalize - This is the entry point for the file.
//
void SelectionDAG::Legalize(bool TypesNeedLegalizing,
CodeGenOpt::Level OptLevel) {
/// run - This is the main entry point to this class.
///
SelectionDAGLegalize(*this, OptLevel).LegalizeDAG();
}