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gerrit-public.fairphone.software / fp2-dev / platform / external / llvm / 23993561e24b2a6eaf0e036062522ab825c30d3f / . / lib / CodeGen / SelectionDAG / LegalizeDAG.cpp
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//===-- LegalizeDAG.cpp - Implement SelectionDAG::Legalize ----------------===//
//
// The LLVM Compiler Infrastructure
//
// This file was developed by the LLVM research group and 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/MachineConstantPool.h"
#include "llvm/CodeGen/MachineFunction.h"
#include "llvm/CodeGen/MachineFrameInfo.h"
#include "llvm/Target/TargetLowering.h"
#include "llvm/Target/TargetData.h"
#include "llvm/Target/TargetOptions.h"
#include "llvm/Constants.h"
#include <iostream>
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 SelectionDAGLegalize {
TargetLowering &TLI;
SelectionDAG &DAG;
/// LegalizeAction - This enum indicates what action we should take for each
/// value type the can occur in the program.
enum LegalizeAction {
Legal, // The target natively supports this value type.
Promote, // This should be promoted to the next larger type.
Expand, // This integer type should be broken into smaller pieces.
};
/// 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)".
unsigned ValueTypeActions;
/// NeedsAnotherIteration - This is set when we expand a large integer
/// operation into smaller integer operations, but the smaller operations are
/// not set. This occurs only rarely in practice, for targets that don't have
/// 32-bit or larger integer registers.
bool NeedsAnotherIteration;
/// 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.
std::map<SDOperand, SDOperand> LegalizedNodes;
/// PromotedNodes - For nodes that are below legal width, and that have more
/// than one use, this map indicates what promoted value to use. This allows
/// us to avoid promoting the same thing more than once.
std::map<SDOperand, SDOperand> PromotedNodes;
/// ExpandedNodes - For nodes that need to be expanded, and which have more
/// than one use, this map indicates which which operands are the expanded
/// version of the input. This allows us to avoid expanding the same node
/// more than once.
std::map<SDOperand, std::pair<SDOperand, SDOperand> > ExpandedNodes;
void AddLegalizedOperand(SDOperand From, SDOperand To) {
bool isNew = LegalizedNodes.insert(std::make_pair(From, To)).second;
assert(isNew && "Got into the map somehow?");
}
void AddPromotedOperand(SDOperand From, SDOperand To) {
bool isNew = PromotedNodes.insert(std::make_pair(From, To)).second;
assert(isNew && "Got into the map somehow?");
}
public:
SelectionDAGLegalize(SelectionDAG &DAG);
/// Run - While there is still lowering to do, perform a pass over the DAG.
/// Most regularization can be done in a single pass, but targets that require
/// large values to be split into registers multiple times (e.g. i64 -> 4x
/// i16) require iteration for these values (the first iteration will demote
/// to i32, the second will demote to i16).
void Run() {
do {
NeedsAnotherIteration = false;
LegalizeDAG();
} while (NeedsAnotherIteration);
}
/// 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::ValueType VT) const {
return (LegalizeAction)((ValueTypeActions >> (2*VT)) & 3);
}
/// isTypeLegal - Return true if this type is legal on this target.
///
bool isTypeLegal(MVT::ValueType VT) const {
return getTypeAction(VT) == Legal;
}
private:
void LegalizeDAG();
SDOperand LegalizeOp(SDOperand O);
void ExpandOp(SDOperand O, SDOperand &Lo, SDOperand &Hi);
SDOperand PromoteOp(SDOperand O);
SDOperand ExpandLibCall(const char *Name, SDNode *Node,
SDOperand &Hi);
SDOperand ExpandIntToFP(bool isSigned, MVT::ValueType DestTy,
SDOperand Source);
bool ExpandShift(unsigned Opc, SDOperand Op, SDOperand Amt,
SDOperand &Lo, SDOperand &Hi);
void ExpandShiftParts(unsigned NodeOp, SDOperand Op, SDOperand Amt,
SDOperand &Lo, SDOperand &Hi);
void ExpandByParts(unsigned NodeOp, SDOperand LHS, SDOperand RHS,
SDOperand &Lo, SDOperand &Hi);
SDOperand getIntPtrConstant(uint64_t Val) {
return DAG.getConstant(Val, TLI.getPointerTy());
}
};
}
SelectionDAGLegalize::SelectionDAGLegalize(SelectionDAG &dag)
: TLI(dag.getTargetLoweringInfo()), DAG(dag),
ValueTypeActions(TLI.getValueTypeActions()) {
assert(MVT::LAST_VALUETYPE <= 16 &&
"Too many value types for ValueTypeActions to hold!");
}
void SelectionDAGLegalize::LegalizeDAG() {
SDOperand OldRoot = DAG.getRoot();
SDOperand NewRoot = LegalizeOp(OldRoot);
DAG.setRoot(NewRoot);
ExpandedNodes.clear();
LegalizedNodes.clear();
PromotedNodes.clear();
// Remove dead nodes now.
DAG.RemoveDeadNodes(OldRoot.Val);
}
SDOperand SelectionDAGLegalize::LegalizeOp(SDOperand Op) {
assert(getTypeAction(Op.getValueType()) == Legal &&
"Caller should expand or promote operands that are not legal!");
// If this operation defines any values that cannot be represented in a
// register on this target, make sure to expand or promote them.
if (Op.Val->getNumValues() > 1) {
for (unsigned i = 0, e = Op.Val->getNumValues(); i != e; ++i)
switch (getTypeAction(Op.Val->getValueType(i))) {
case Legal: break; // Nothing to do.
case Expand: {
SDOperand T1, T2;
ExpandOp(Op.getValue(i), T1, T2);
assert(LegalizedNodes.count(Op) &&
"Expansion didn't add legal operands!");
return LegalizedNodes[Op];
}
case Promote:
PromoteOp(Op.getValue(i));
assert(LegalizedNodes.count(Op) &&
"Expansion didn't add legal operands!");
return LegalizedNodes[Op];
}
}
std::map<SDOperand, SDOperand>::iterator I = LegalizedNodes.find(Op);
if (I != LegalizedNodes.end()) return I->second;
SDOperand Tmp1, Tmp2, Tmp3;
SDOperand Result = Op;
SDNode *Node = Op.Val;
switch (Node->getOpcode()) {
default:
std::cerr << "NODE: "; Node->dump(); std::cerr << "\n";
assert(0 && "Do not know how to legalize this operator!");
abort();
case ISD::EntryToken:
case ISD::FrameIndex:
case ISD::GlobalAddress:
case ISD::ExternalSymbol:
case ISD::ConstantPool: // Nothing to do.
assert(getTypeAction(Node->getValueType(0)) == Legal &&
"This must be legal!");
break;
case ISD::CopyFromReg:
Tmp1 = LegalizeOp(Node->getOperand(0));
if (Tmp1 != Node->getOperand(0))
Result = DAG.getCopyFromReg(cast<RegSDNode>(Node)->getReg(),
Node->getValueType(0), Tmp1);
else
Result = Op.getValue(0);
// Since CopyFromReg produces two values, make sure to remember that we
// legalized both of them.
AddLegalizedOperand(Op.getValue(0), Result);
AddLegalizedOperand(Op.getValue(1), Result.getValue(1));
return Result.getValue(Op.ResNo);
case ISD::ImplicitDef:
Tmp1 = LegalizeOp(Node->getOperand(0));
if (Tmp1 != Node->getOperand(0))
Result = DAG.getImplicitDef(Tmp1, cast<RegSDNode>(Node)->getReg());
break;
case ISD::UNDEF: {
MVT::ValueType VT = Op.getValueType();
switch (TLI.getOperationAction(ISD::UNDEF, VT)) {
default: assert(0 && "This action is not supported yet!");
case TargetLowering::Expand:
case TargetLowering::Promote:
if (MVT::isInteger(VT))
Result = DAG.getConstant(0, VT);
else if (MVT::isFloatingPoint(VT))
Result = DAG.getConstantFP(0, VT);
else
assert(0 && "Unknown value type!");
break;
case TargetLowering::Legal:
break;
}
break;
}
case ISD::Constant:
// We know we don't need to expand constants here, constants only have one
// value and we check that it is fine above.
// FIXME: Maybe we should handle things like targets that don't support full
// 32-bit immediates?
break;
case ISD::ConstantFP: {
// Spill FP immediates to the constant pool if the target cannot directly
// codegen them. Targets often have some immediate values that can be
// efficiently generated into an FP register without a load. We explicitly
// leave these constants as ConstantFP nodes for the target to deal with.
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 (!isLegal) {
// Otherwise we need to spill the constant to memory.
MachineConstantPool *CP = DAG.getMachineFunction().getConstantPool();
bool Extend = false;
// If a FP immediate is precise when represented as a float, we put it
// into the constant pool as a float, even if it's is statically typed
// as a double.
MVT::ValueType VT = CFP->getValueType(0);
bool isDouble = VT == MVT::f64;
ConstantFP *LLVMC = ConstantFP::get(isDouble ? Type::DoubleTy :
Type::FloatTy, CFP->getValue());
if (isDouble && CFP->isExactlyValue((float)CFP->getValue()) &&
// Only do this if the target has a native EXTLOAD instruction from
// f32.
TLI.getOperationAction(ISD::EXTLOAD,
MVT::f32) == TargetLowering::Legal) {
LLVMC = cast<ConstantFP>(ConstantExpr::getCast(LLVMC, Type::FloatTy));
VT = MVT::f32;
Extend = true;
}
SDOperand CPIdx = DAG.getConstantPool(CP->getConstantPoolIndex(LLVMC),
TLI.getPointerTy());
if (Extend) {
Result = DAG.getNode(ISD::EXTLOAD, MVT::f64, DAG.getEntryNode(), CPIdx,
MVT::f32);
} else {
Result = DAG.getLoad(VT, DAG.getEntryNode(), CPIdx);
}
}
break;
}
case ISD::TokenFactor: {
std::vector<SDOperand> Ops;
bool Changed = false;
for (unsigned i = 0, e = Node->getNumOperands(); i != e; ++i) {
SDOperand Op = Node->getOperand(i);
// Fold single-use TokenFactor nodes into this token factor as we go.
if (Op.getOpcode() == ISD::TokenFactor && Op.hasOneUse()) {
Changed = true;
for (unsigned j = 0, e = Op.getNumOperands(); j != e; ++j)
Ops.push_back(LegalizeOp(Op.getOperand(j)));
} else {
Ops.push_back(LegalizeOp(Op)); // Legalize the operands
Changed |= Ops[i] != Op;
}
}
if (Changed)
Result = DAG.getNode(ISD::TokenFactor, MVT::Other, Ops);
break;
}
case ISD::ADJCALLSTACKDOWN:
case ISD::ADJCALLSTACKUP:
Tmp1 = LegalizeOp(Node->getOperand(0)); // Legalize the chain.
// There is no need to legalize the size argument (Operand #1)
if (Tmp1 != Node->getOperand(0))
Result = DAG.getNode(Node->getOpcode(), MVT::Other, Tmp1,
Node->getOperand(1));
break;
case ISD::DYNAMIC_STACKALLOC:
Tmp1 = LegalizeOp(Node->getOperand(0)); // Legalize the chain.
Tmp2 = LegalizeOp(Node->getOperand(1)); // Legalize the size.
Tmp3 = LegalizeOp(Node->getOperand(2)); // Legalize the alignment.
if (Tmp1 != Node->getOperand(0) || Tmp2 != Node->getOperand(1) ||
Tmp3 != Node->getOperand(2))
Result = DAG.getNode(ISD::DYNAMIC_STACKALLOC, Node->getValueType(0),
Tmp1, Tmp2, Tmp3);
else
Result = Op.getValue(0);
// Since this op produces two values, make sure to remember that we
// legalized both of them.
AddLegalizedOperand(SDOperand(Node, 0), Result);
AddLegalizedOperand(SDOperand(Node, 1), Result.getValue(1));
return Result.getValue(Op.ResNo);
case ISD::CALL: {
Tmp1 = LegalizeOp(Node->getOperand(0)); // Legalize the chain.
Tmp2 = LegalizeOp(Node->getOperand(1)); // Legalize the callee.
bool Changed = false;
std::vector<SDOperand> Ops;
for (unsigned i = 2, e = Node->getNumOperands(); i != e; ++i) {
Ops.push_back(LegalizeOp(Node->getOperand(i)));
Changed |= Ops.back() != Node->getOperand(i);
}
if (Tmp1 != Node->getOperand(0) || Tmp2 != Node->getOperand(1) || Changed) {
std::vector<MVT::ValueType> RetTyVTs;
RetTyVTs.reserve(Node->getNumValues());
for (unsigned i = 0, e = Node->getNumValues(); i != e; ++i)
RetTyVTs.push_back(Node->getValueType(i));
Result = SDOperand(DAG.getCall(RetTyVTs, Tmp1, Tmp2, Ops), 0);
} else {
Result = Result.getValue(0);
}
// Since calls produce multiple values, make sure to remember that we
// legalized all of them.
for (unsigned i = 0, e = Node->getNumValues(); i != e; ++i)
AddLegalizedOperand(SDOperand(Node, i), Result.getValue(i));
return Result.getValue(Op.ResNo);
}
case ISD::BR:
Tmp1 = LegalizeOp(Node->getOperand(0)); // Legalize the chain.
if (Tmp1 != Node->getOperand(0))
Result = DAG.getNode(ISD::BR, MVT::Other, Tmp1, Node->getOperand(1));
break;
case ISD::BRCOND:
Tmp1 = LegalizeOp(Node->getOperand(0)); // Legalize the chain.
switch (getTypeAction(Node->getOperand(1).getValueType())) {
case Expand: assert(0 && "It's impossible to expand bools");
case Legal:
Tmp2 = LegalizeOp(Node->getOperand(1)); // Legalize the condition.
break;
case Promote:
Tmp2 = PromoteOp(Node->getOperand(1)); // Promote the condition.
break;
}
// Basic block destination (Op#2) is always legal.
if (Tmp1 != Node->getOperand(0) || Tmp2 != Node->getOperand(1))
Result = DAG.getNode(ISD::BRCOND, MVT::Other, Tmp1, Tmp2,
Node->getOperand(2));
break;
case ISD::BRCONDTWOWAY:
Tmp1 = LegalizeOp(Node->getOperand(0)); // Legalize the chain.
switch (getTypeAction(Node->getOperand(1).getValueType())) {
case Expand: assert(0 && "It's impossible to expand bools");
case Legal:
Tmp2 = LegalizeOp(Node->getOperand(1)); // Legalize the condition.
break;
case Promote:
Tmp2 = PromoteOp(Node->getOperand(1)); // Promote the condition.
break;
}
// If this target does not support BRCONDTWOWAY, lower it to a BRCOND/BR
// pair.
switch (TLI.getOperationAction(ISD::BRCONDTWOWAY, MVT::Other)) {
case TargetLowering::Promote:
default: assert(0 && "This action is not supported yet!");
case TargetLowering::Legal:
if (Tmp1 != Node->getOperand(0) || Tmp2 != Node->getOperand(1)) {
std::vector<SDOperand> Ops;
Ops.push_back(Tmp1);
Ops.push_back(Tmp2);
Ops.push_back(Node->getOperand(2));
Ops.push_back(Node->getOperand(3));
Result = DAG.getNode(ISD::BRCONDTWOWAY, MVT::Other, Ops);
}
break;
case TargetLowering::Expand:
Result = DAG.getNode(ISD::BRCOND, MVT::Other, Tmp1, Tmp2,
Node->getOperand(2));
Result = DAG.getNode(ISD::BR, MVT::Other, Result, Node->getOperand(3));
break;
}
break;
case ISD::LOAD:
Tmp1 = LegalizeOp(Node->getOperand(0)); // Legalize the chain.
Tmp2 = LegalizeOp(Node->getOperand(1)); // Legalize the pointer.
if (Tmp1 != Node->getOperand(0) ||
Tmp2 != Node->getOperand(1))
Result = DAG.getLoad(Node->getValueType(0), Tmp1, Tmp2);
else
Result = SDOperand(Node, 0);
// Since loads produce two values, make sure to remember that we legalized
// both of them.
AddLegalizedOperand(SDOperand(Node, 0), Result);
AddLegalizedOperand(SDOperand(Node, 1), Result.getValue(1));
return Result.getValue(Op.ResNo);
case ISD::EXTLOAD:
case ISD::SEXTLOAD:
case ISD::ZEXTLOAD: {
Tmp1 = LegalizeOp(Node->getOperand(0)); // Legalize the chain.
Tmp2 = LegalizeOp(Node->getOperand(1)); // Legalize the pointer.
MVT::ValueType SrcVT = cast<MVTSDNode>(Node)->getExtraValueType();
switch (TLI.getOperationAction(Node->getOpcode(), SrcVT)) {
default: assert(0 && "This action is not supported yet!");
case TargetLowering::Promote:
assert(SrcVT == MVT::i1 && "Can only promote EXTLOAD from i1 -> i8!");
Result = DAG.getNode(Node->getOpcode(), Node->getValueType(0),
Tmp1, Tmp2, MVT::i8);
// Since loads produce two values, make sure to remember that we legalized
// both of them.
AddLegalizedOperand(SDOperand(Node, 0), Result);
AddLegalizedOperand(SDOperand(Node, 1), Result.getValue(1));
return Result.getValue(Op.ResNo);
case TargetLowering::Legal:
if (Tmp1 != Node->getOperand(0) ||
Tmp2 != Node->getOperand(1))
Result = DAG.getNode(Node->getOpcode(), Node->getValueType(0),
Tmp1, Tmp2, SrcVT);
else
Result = SDOperand(Node, 0);
// Since loads produce two values, make sure to remember that we legalized
// both of them.
AddLegalizedOperand(SDOperand(Node, 0), Result);
AddLegalizedOperand(SDOperand(Node, 1), Result.getValue(1));
return Result.getValue(Op.ResNo);
case TargetLowering::Expand:
assert(Node->getOpcode() != ISD::EXTLOAD &&
"EXTLOAD should always be supported!");
// Turn the unsupported load into an EXTLOAD followed by an explicit
// zero/sign extend inreg.
Result = DAG.getNode(ISD::EXTLOAD, Node->getValueType(0),
Tmp1, Tmp2, SrcVT);
SDOperand ValRes;
if (Node->getOpcode() == ISD::SEXTLOAD)
ValRes = DAG.getNode(ISD::SIGN_EXTEND_INREG, Result.getValueType(),
Result, SrcVT);
else
ValRes = DAG.getZeroExtendInReg(Result, SrcVT);
AddLegalizedOperand(SDOperand(Node, 0), ValRes);
AddLegalizedOperand(SDOperand(Node, 1), Result.getValue(1));
if (Op.ResNo)
return Result.getValue(1);
return ValRes;
}
assert(0 && "Unreachable");
}
case ISD::EXTRACT_ELEMENT:
// Get both the low and high parts.
ExpandOp(Node->getOperand(0), Tmp1, Tmp2);
if (cast<ConstantSDNode>(Node->getOperand(1))->getValue())
Result = Tmp2; // 1 -> Hi
else
Result = Tmp1; // 0 -> Lo
break;
case ISD::CopyToReg:
Tmp1 = LegalizeOp(Node->getOperand(0)); // Legalize the chain.
switch (getTypeAction(Node->getOperand(1).getValueType())) {
case Legal:
// Legalize the incoming value (must be legal).
Tmp2 = LegalizeOp(Node->getOperand(1));
if (Tmp1 != Node->getOperand(0) || Tmp2 != Node->getOperand(1))
Result = DAG.getCopyToReg(Tmp1, Tmp2, cast<RegSDNode>(Node)->getReg());
break;
case Promote:
Tmp2 = PromoteOp(Node->getOperand(1));
Result = DAG.getCopyToReg(Tmp1, Tmp2, cast<RegSDNode>(Node)->getReg());
break;
case Expand:
SDOperand Lo, Hi;
ExpandOp(Node->getOperand(1), Lo, Hi);
unsigned Reg = cast<RegSDNode>(Node)->getReg();
Lo = DAG.getCopyToReg(Tmp1, Lo, Reg);
Hi = DAG.getCopyToReg(Tmp1, Hi, Reg+1);
// Note that the copytoreg nodes are independent of each other.
Result = DAG.getNode(ISD::TokenFactor, MVT::Other, Lo, Hi);
assert(isTypeLegal(Result.getValueType()) &&
"Cannot expand multiple times yet (i64 -> i16)");
break;
}
break;
case ISD::RET:
Tmp1 = LegalizeOp(Node->getOperand(0)); // Legalize the chain.
switch (Node->getNumOperands()) {
case 2: // ret val
switch (getTypeAction(Node->getOperand(1).getValueType())) {
case Legal:
Tmp2 = LegalizeOp(Node->getOperand(1));
if (Tmp1 != Node->getOperand(0) || Tmp2 != Node->getOperand(1))
Result = DAG.getNode(ISD::RET, MVT::Other, Tmp1, Tmp2);
break;
case Expand: {
SDOperand Lo, Hi;
ExpandOp(Node->getOperand(1), Lo, Hi);
Result = DAG.getNode(ISD::RET, MVT::Other, Tmp1, Lo, Hi);
break;
}
case Promote:
Tmp2 = PromoteOp(Node->getOperand(1));
Result = DAG.getNode(ISD::RET, MVT::Other, Tmp1, Tmp2);
break;
}
break;
case 1: // ret void
if (Tmp1 != Node->getOperand(0))
Result = DAG.getNode(ISD::RET, MVT::Other, Tmp1);
break;
default: { // ret <values>
std::vector<SDOperand> NewValues;
NewValues.push_back(Tmp1);
for (unsigned i = 1, e = Node->getNumOperands(); i != e; ++i)
switch (getTypeAction(Node->getOperand(i).getValueType())) {
case Legal:
NewValues.push_back(LegalizeOp(Node->getOperand(i)));
break;
case Expand: {
SDOperand Lo, Hi;
ExpandOp(Node->getOperand(i), Lo, Hi);
NewValues.push_back(Lo);
NewValues.push_back(Hi);
break;
}
case Promote:
assert(0 && "Can't promote multiple return value yet!");
}
Result = DAG.getNode(ISD::RET, MVT::Other, NewValues);
break;
}
}
break;
case ISD::STORE:
Tmp1 = LegalizeOp(Node->getOperand(0)); // Legalize the chain.
Tmp2 = LegalizeOp(Node->getOperand(2)); // Legalize the pointer.
// Turn 'store float 1.0, Ptr' -> 'store int 0x12345678, Ptr'
if (ConstantFPSDNode *CFP =dyn_cast<ConstantFPSDNode>(Node->getOperand(1))){
if (CFP->getValueType(0) == MVT::f32) {
union {
unsigned I;
float F;
} V;
V.F = CFP->getValue();
Result = DAG.getNode(ISD::STORE, MVT::Other, Tmp1,
DAG.getConstant(V.I, MVT::i32), Tmp2);
} else {
assert(CFP->getValueType(0) == MVT::f64 && "Unknown FP type!");
union {
uint64_t I;
double F;
} V;
V.F = CFP->getValue();
Result = DAG.getNode(ISD::STORE, MVT::Other, Tmp1,
DAG.getConstant(V.I, MVT::i64), Tmp2);
}
Node = Result.Val;
}
switch (getTypeAction(Node->getOperand(1).getValueType())) {
case Legal: {
SDOperand Val = LegalizeOp(Node->getOperand(1));
if (Val != Node->getOperand(1) || Tmp1 != Node->getOperand(0) ||
Tmp2 != Node->getOperand(2))
Result = DAG.getNode(ISD::STORE, MVT::Other, Tmp1, Val, Tmp2);
break;
}
case Promote:
// Truncate the value and store the result.
Tmp3 = PromoteOp(Node->getOperand(1));
Result = DAG.getNode(ISD::TRUNCSTORE, MVT::Other, Tmp1, Tmp3, Tmp2,
Node->getOperand(1).getValueType());
break;
case Expand:
SDOperand Lo, Hi;
ExpandOp(Node->getOperand(1), Lo, Hi);
if (!TLI.isLittleEndian())
std::swap(Lo, Hi);
Lo = DAG.getNode(ISD::STORE, MVT::Other, Tmp1, Lo, Tmp2);
unsigned IncrementSize = MVT::getSizeInBits(Hi.getValueType())/8;
Tmp2 = DAG.getNode(ISD::ADD, Tmp2.getValueType(), Tmp2,
getIntPtrConstant(IncrementSize));
assert(isTypeLegal(Tmp2.getValueType()) &&
"Pointers must be legal!");
Hi = DAG.getNode(ISD::STORE, MVT::Other, Tmp1, Hi, Tmp2);
Result = DAG.getNode(ISD::TokenFactor, MVT::Other, Lo, Hi);
break;
}
break;
case ISD::PCMARKER:
Tmp1 = LegalizeOp(Node->getOperand(0)); // Legalize the chain.
if (Tmp1 != Node->getOperand(0))
Result = DAG.getNode(ISD::PCMARKER, MVT::Other, Tmp1,Node->getOperand(1));
break;
case ISD::TRUNCSTORE:
Tmp1 = LegalizeOp(Node->getOperand(0)); // Legalize the chain.
Tmp3 = LegalizeOp(Node->getOperand(2)); // Legalize the pointer.
switch (getTypeAction(Node->getOperand(1).getValueType())) {
case Legal:
Tmp2 = LegalizeOp(Node->getOperand(1));
if (Tmp1 != Node->getOperand(0) || Tmp2 != Node->getOperand(1) ||
Tmp3 != Node->getOperand(2))
Result = DAG.getNode(ISD::TRUNCSTORE, MVT::Other, Tmp1, Tmp2, Tmp3,
cast<MVTSDNode>(Node)->getExtraValueType());
break;
case Promote:
case Expand:
assert(0 && "Cannot handle illegal TRUNCSTORE yet!");
}
break;
case ISD::SELECT:
switch (getTypeAction(Node->getOperand(0).getValueType())) {
case Expand: assert(0 && "It's impossible to expand bools");
case Legal:
Tmp1 = LegalizeOp(Node->getOperand(0)); // Legalize the condition.
break;
case Promote:
Tmp1 = PromoteOp(Node->getOperand(0)); // Promote the condition.
break;
}
Tmp2 = LegalizeOp(Node->getOperand(1)); // TrueVal
Tmp3 = LegalizeOp(Node->getOperand(2)); // FalseVal
switch (TLI.getOperationAction(Node->getOpcode(), Tmp2.getValueType())) {
default: assert(0 && "This action is not supported yet!");
case TargetLowering::Legal:
if (Tmp1 != Node->getOperand(0) || Tmp2 != Node->getOperand(1) ||
Tmp3 != Node->getOperand(2))
Result = DAG.getNode(ISD::SELECT, Node->getValueType(0),
Tmp1, Tmp2, Tmp3);
break;
case TargetLowering::Promote: {
MVT::ValueType NVT =
TLI.getTypeToPromoteTo(ISD::SELECT, Tmp2.getValueType());
unsigned ExtOp, TruncOp;
if (MVT::isInteger(Tmp2.getValueType())) {
ExtOp = ISD::ZERO_EXTEND;
TruncOp = ISD::TRUNCATE;
} else {
ExtOp = ISD::FP_EXTEND;
TruncOp = ISD::FP_ROUND;
}
// Promote each of the values to the new type.
Tmp2 = DAG.getNode(ExtOp, NVT, Tmp2);
Tmp3 = DAG.getNode(ExtOp, NVT, Tmp3);
// Perform the larger operation, then round down.
Result = DAG.getNode(ISD::SELECT, NVT, Tmp1, Tmp2,Tmp3);
Result = DAG.getNode(TruncOp, Node->getValueType(0), Result);
break;
}
}
break;
case ISD::SETCC:
switch (getTypeAction(Node->getOperand(0).getValueType())) {
case Legal:
Tmp1 = LegalizeOp(Node->getOperand(0)); // LHS
Tmp2 = LegalizeOp(Node->getOperand(1)); // RHS
if (Tmp1 != Node->getOperand(0) || Tmp2 != Node->getOperand(1))
Result = DAG.getSetCC(cast<SetCCSDNode>(Node)->getCondition(),
Node->getValueType(0), Tmp1, Tmp2);
break;
case Promote:
Tmp1 = PromoteOp(Node->getOperand(0)); // LHS
Tmp2 = PromoteOp(Node->getOperand(1)); // RHS
// If this is an FP compare, the operands have already been extended.
if (MVT::isInteger(Node->getOperand(0).getValueType())) {
MVT::ValueType VT = Node->getOperand(0).getValueType();
MVT::ValueType NVT = TLI.getTypeToTransformTo(VT);
// Otherwise, we have to insert explicit sign or zero extends. Note
// that we could insert sign extends for ALL conditions, but zero extend
// is cheaper on many machines (an AND instead of two shifts), so prefer
// it.
switch (cast<SetCCSDNode>(Node)->getCondition()) {
default: assert(0 && "Unknown integer comparison!");
case ISD::SETEQ:
case ISD::SETNE:
case ISD::SETUGE:
case ISD::SETUGT:
case ISD::SETULE:
case ISD::SETULT:
// ALL of these operations will work if we either sign or zero extend
// the operands (including the unsigned comparisons!). Zero extend is
// usually a simpler/cheaper operation, so prefer it.
Tmp1 = DAG.getZeroExtendInReg(Tmp1, VT);
Tmp2 = DAG.getZeroExtendInReg(Tmp2, VT);
break;
case ISD::SETGE:
case ISD::SETGT:
case ISD::SETLT:
case ISD::SETLE:
Tmp1 = DAG.getNode(ISD::SIGN_EXTEND_INREG, NVT, Tmp1, VT);
Tmp2 = DAG.getNode(ISD::SIGN_EXTEND_INREG, NVT, Tmp2, VT);
break;
}
}
Result = DAG.getSetCC(cast<SetCCSDNode>(Node)->getCondition(),
Node->getValueType(0), Tmp1, Tmp2);
break;
case Expand:
SDOperand LHSLo, LHSHi, RHSLo, RHSHi;
ExpandOp(Node->getOperand(0), LHSLo, LHSHi);
ExpandOp(Node->getOperand(1), RHSLo, RHSHi);
switch (cast<SetCCSDNode>(Node)->getCondition()) {
case ISD::SETEQ:
case ISD::SETNE:
if (RHSLo == RHSHi)
if (ConstantSDNode *RHSCST = dyn_cast<ConstantSDNode>(RHSLo))
if (RHSCST->isAllOnesValue()) {
// Comparison to -1.
Tmp1 = DAG.getNode(ISD::AND, LHSLo.getValueType(), LHSLo, LHSHi);
Result = DAG.getSetCC(cast<SetCCSDNode>(Node)->getCondition(),
Node->getValueType(0), Tmp1, RHSLo);
break;
}
Tmp1 = DAG.getNode(ISD::XOR, LHSLo.getValueType(), LHSLo, RHSLo);
Tmp2 = DAG.getNode(ISD::XOR, LHSLo.getValueType(), LHSHi, RHSHi);
Tmp1 = DAG.getNode(ISD::OR, Tmp1.getValueType(), Tmp1, Tmp2);
Result = DAG.getSetCC(cast<SetCCSDNode>(Node)->getCondition(),
Node->getValueType(0), Tmp1,
DAG.getConstant(0, Tmp1.getValueType()));
break;
default:
// If this is a comparison of the sign bit, just look at the top part.
// X > -1, x < 0
if (ConstantSDNode *CST = dyn_cast<ConstantSDNode>(Node->getOperand(1)))
if ((cast<SetCCSDNode>(Node)->getCondition() == ISD::SETLT &&
CST->getValue() == 0) || // X < 0
(cast<SetCCSDNode>(Node)->getCondition() == ISD::SETGT &&
(CST->isAllOnesValue()))) // X > -1
return DAG.getSetCC(cast<SetCCSDNode>(Node)->getCondition(),
Node->getValueType(0), LHSHi, RHSHi);
// FIXME: This generated code sucks.
ISD::CondCode LowCC;
switch (cast<SetCCSDNode>(Node)->getCondition()) {
default: assert(0 && "Unknown integer setcc!");
case ISD::SETLT:
case ISD::SETULT: LowCC = ISD::SETULT; break;
case ISD::SETGT:
case ISD::SETUGT: LowCC = ISD::SETUGT; break;
case ISD::SETLE:
case ISD::SETULE: LowCC = ISD::SETULE; break;
case ISD::SETGE:
case ISD::SETUGE: LowCC = ISD::SETUGE; break;
}
// Tmp1 = lo(op1) < lo(op2) // Always unsigned comparison
// Tmp2 = hi(op1) < hi(op2) // Signedness depends on operands
// dest = hi(op1) == hi(op2) ? Tmp1 : Tmp2;
// NOTE: on targets without efficient SELECT of bools, we can always use
// this identity: (B1 ? B2 : B3) --> (B1 & B2)|(!B1&B3)
Tmp1 = DAG.getSetCC(LowCC, Node->getValueType(0), LHSLo, RHSLo);
Tmp2 = DAG.getSetCC(cast<SetCCSDNode>(Node)->getCondition(),
Node->getValueType(0), LHSHi, RHSHi);
Result = DAG.getSetCC(ISD::SETEQ, Node->getValueType(0), LHSHi, RHSHi);
Result = DAG.getNode(ISD::SELECT, Tmp1.getValueType(),
Result, Tmp1, Tmp2);
break;
}
}
break;
case ISD::MEMSET:
case ISD::MEMCPY:
case ISD::MEMMOVE: {
Tmp1 = LegalizeOp(Node->getOperand(0)); // Chain
Tmp2 = LegalizeOp(Node->getOperand(1)); // Pointer
if (Node->getOpcode() == ISD::MEMSET) { // memset = ubyte
switch (getTypeAction(Node->getOperand(2).getValueType())) {
case Expand: assert(0 && "Cannot expand a byte!");
case Legal:
Tmp3 = LegalizeOp(Node->getOperand(2));
break;
case Promote:
Tmp3 = PromoteOp(Node->getOperand(2));
break;
}
} else {
Tmp3 = LegalizeOp(Node->getOperand(2)); // memcpy/move = pointer,
}
SDOperand Tmp4;
switch (getTypeAction(Node->getOperand(3).getValueType())) {
case Expand: assert(0 && "Cannot expand this yet!");
case Legal:
Tmp4 = LegalizeOp(Node->getOperand(3));
break;
case Promote:
Tmp4 = PromoteOp(Node->getOperand(3));
break;
}
SDOperand Tmp5;
switch (getTypeAction(Node->getOperand(4).getValueType())) { // uint
case Expand: assert(0 && "Cannot expand this yet!");
case Legal:
Tmp5 = LegalizeOp(Node->getOperand(4));
break;
case Promote:
Tmp5 = PromoteOp(Node->getOperand(4));
break;
}
switch (TLI.getOperationAction(Node->getOpcode(), MVT::Other)) {
default: assert(0 && "This action not implemented for this operation!");
case TargetLowering::Legal:
if (Tmp1 != Node->getOperand(0) || Tmp2 != Node->getOperand(1) ||
Tmp3 != Node->getOperand(2) || Tmp4 != Node->getOperand(3) ||
Tmp5 != Node->getOperand(4)) {
std::vector<SDOperand> Ops;
Ops.push_back(Tmp1); Ops.push_back(Tmp2); Ops.push_back(Tmp3);
Ops.push_back(Tmp4); Ops.push_back(Tmp5);
Result = DAG.getNode(Node->getOpcode(), MVT::Other, Ops);
}
break;
case TargetLowering::Expand: {
// Otherwise, the target does not support this operation. Lower the
// operation to an explicit libcall as appropriate.
MVT::ValueType IntPtr = TLI.getPointerTy();
const Type *IntPtrTy = TLI.getTargetData().getIntPtrType();
std::vector<std::pair<SDOperand, const Type*> > Args;
const char *FnName = 0;
if (Node->getOpcode() == ISD::MEMSET) {
Args.push_back(std::make_pair(Tmp2, IntPtrTy));
// Extend the ubyte argument to be an int value for the call.
Tmp3 = DAG.getNode(ISD::ZERO_EXTEND, MVT::i32, Tmp3);
Args.push_back(std::make_pair(Tmp3, Type::IntTy));
Args.push_back(std::make_pair(Tmp4, IntPtrTy));
FnName = "memset";
} else if (Node->getOpcode() == ISD::MEMCPY ||
Node->getOpcode() == ISD::MEMMOVE) {
Args.push_back(std::make_pair(Tmp2, IntPtrTy));
Args.push_back(std::make_pair(Tmp3, IntPtrTy));
Args.push_back(std::make_pair(Tmp4, IntPtrTy));
FnName = Node->getOpcode() == ISD::MEMMOVE ? "memmove" : "memcpy";
} else {
assert(0 && "Unknown op!");
}
std::pair<SDOperand,SDOperand> CallResult =
TLI.LowerCallTo(Tmp1, Type::VoidTy, false,
DAG.getExternalSymbol(FnName, IntPtr), Args, DAG);
Result = LegalizeOp(CallResult.second);
break;
}
case TargetLowering::Custom:
std::vector<SDOperand> Ops;
Ops.push_back(Tmp1); Ops.push_back(Tmp2); Ops.push_back(Tmp3);
Ops.push_back(Tmp4); Ops.push_back(Tmp5);
Result = DAG.getNode(Node->getOpcode(), MVT::Other, Ops);
Result = TLI.LowerOperation(Result);
Result = LegalizeOp(Result);
break;
}
break;
}
case ISD::ADD_PARTS:
case ISD::SUB_PARTS:
case ISD::SHL_PARTS:
case ISD::SRA_PARTS:
case ISD::SRL_PARTS: {
std::vector<SDOperand> Ops;
bool Changed = false;
for (unsigned i = 0, e = Node->getNumOperands(); i != e; ++i) {
Ops.push_back(LegalizeOp(Node->getOperand(i)));
Changed |= Ops.back() != Node->getOperand(i);
}
if (Changed)
Result = DAG.getNode(Node->getOpcode(), Node->getValueType(0), Ops);
// Since these produce multiple values, make sure to remember that we
// legalized all of them.
for (unsigned i = 0, e = Node->getNumValues(); i != e; ++i)
AddLegalizedOperand(SDOperand(Node, i), Result.getValue(i));
return Result.getValue(Op.ResNo);
}
// Binary operators
case ISD::ADD:
case ISD::SUB:
case ISD::MUL:
case ISD::MULHS:
case ISD::MULHU:
case ISD::UDIV:
case ISD::SDIV:
case ISD::AND:
case ISD::OR:
case ISD::XOR:
case ISD::SHL:
case ISD::SRL:
case ISD::SRA:
Tmp1 = LegalizeOp(Node->getOperand(0)); // LHS
Tmp2 = LegalizeOp(Node->getOperand(1)); // RHS
if (Tmp1 != Node->getOperand(0) ||
Tmp2 != Node->getOperand(1))
Result = DAG.getNode(Node->getOpcode(), Node->getValueType(0), Tmp1,Tmp2);
break;
case ISD::UREM:
case ISD::SREM:
Tmp1 = LegalizeOp(Node->getOperand(0)); // LHS
Tmp2 = LegalizeOp(Node->getOperand(1)); // RHS
switch (TLI.getOperationAction(Node->getOpcode(), Node->getValueType(0))) {
case TargetLowering::Legal:
if (Tmp1 != Node->getOperand(0) ||
Tmp2 != Node->getOperand(1))
Result = DAG.getNode(Node->getOpcode(), Node->getValueType(0), Tmp1,
Tmp2);
break;
case TargetLowering::Promote:
case TargetLowering::Custom:
assert(0 && "Cannot promote/custom handle this yet!");
case TargetLowering::Expand: {
MVT::ValueType VT = Node->getValueType(0);
unsigned Opc = (Node->getOpcode() == ISD::UREM) ? ISD::UDIV : ISD::SDIV;
Result = DAG.getNode(Opc, VT, Tmp1, Tmp2);
Result = DAG.getNode(ISD::MUL, VT, Result, Tmp2);
Result = DAG.getNode(ISD::SUB, VT, Tmp1, Result);
}
break;
}
break;
// Unary operators
case ISD::FABS:
case ISD::FNEG:
Tmp1 = LegalizeOp(Node->getOperand(0));
switch (TLI.getOperationAction(Node->getOpcode(), Node->getValueType(0))) {
case TargetLowering::Legal:
if (Tmp1 != Node->getOperand(0))
Result = DAG.getNode(Node->getOpcode(), Node->getValueType(0), Tmp1);
break;
case TargetLowering::Promote:
case TargetLowering::Custom:
assert(0 && "Cannot promote/custom handle this yet!");
case TargetLowering::Expand:
if (Node->getOpcode() == ISD::FNEG) {
// Expand Y = FNEG(X) -> Y = SUB -0.0, X
Tmp2 = DAG.getConstantFP(-0.0, Node->getValueType(0));
Result = LegalizeOp(DAG.getNode(ISD::SUB, Node->getValueType(0),
Tmp2, Tmp1));
} else if (Node->getOpcode() == ISD::FABS) {
// Expand Y = FABS(X) -> Y = (X >u 0.0) ? X : fneg(X).
MVT::ValueType VT = Node->getValueType(0);
Tmp2 = DAG.getConstantFP(0.0, VT);
Tmp2 = DAG.getSetCC(ISD::SETUGT, TLI.getSetCCResultTy(), Tmp1, Tmp2);
Tmp3 = DAG.getNode(ISD::FNEG, VT, Tmp1);
Result = DAG.getNode(ISD::SELECT, VT, Tmp2, Tmp1, Tmp3);
Result = LegalizeOp(Result);
} else {
assert(0 && "Unreachable!");
}
break;
}
break;
// Conversion operators. The source and destination have different types.
case ISD::ZERO_EXTEND:
case ISD::SIGN_EXTEND:
case ISD::TRUNCATE:
case ISD::FP_EXTEND:
case ISD::FP_ROUND:
case ISD::FP_TO_SINT:
case ISD::FP_TO_UINT:
case ISD::SINT_TO_FP:
case ISD::UINT_TO_FP:
switch (getTypeAction(Node->getOperand(0).getValueType())) {
case Legal:
Tmp1 = LegalizeOp(Node->getOperand(0));
if (Tmp1 != Node->getOperand(0))
Result = DAG.getNode(Node->getOpcode(), Node->getValueType(0), Tmp1);
break;
case Expand:
if (Node->getOpcode() == ISD::SINT_TO_FP ||
Node->getOpcode() == ISD::UINT_TO_FP) {
Result = ExpandIntToFP(Node->getOpcode() == ISD::SINT_TO_FP,
Node->getValueType(0), Node->getOperand(0));
Result = LegalizeOp(Result);
break;
} else if (Node->getOpcode() == ISD::TRUNCATE) {
// In the expand case, we must be dealing with a truncate, because
// otherwise the result would be larger than the source.
ExpandOp(Node->getOperand(0), Tmp1, Tmp2);
// Since the result is legal, we should just be able to truncate the low
// part of the source.
Result = DAG.getNode(ISD::TRUNCATE, Node->getValueType(0), Tmp1);
break;
}
assert(0 && "Shouldn't need to expand other operators here!");
case Promote:
switch (Node->getOpcode()) {
case ISD::ZERO_EXTEND:
Result = PromoteOp(Node->getOperand(0));
// NOTE: Any extend would work here...
Result = DAG.getNode(ISD::ZERO_EXTEND, Op.getValueType(), Result);
Result = DAG.getZeroExtendInReg(Result,
Node->getOperand(0).getValueType());
break;
case ISD::SIGN_EXTEND:
Result = PromoteOp(Node->getOperand(0));
// NOTE: Any extend would work here...
Result = DAG.getNode(ISD::ZERO_EXTEND, Op.getValueType(), Result);
Result = DAG.getNode(ISD::SIGN_EXTEND_INREG, Result.getValueType(),
Result, Node->getOperand(0).getValueType());
break;
case ISD::TRUNCATE:
Result = PromoteOp(Node->getOperand(0));
Result = DAG.getNode(ISD::TRUNCATE, Op.getValueType(), Result);
break;
case ISD::FP_EXTEND:
Result = PromoteOp(Node->getOperand(0));
if (Result.getValueType() != Op.getValueType())
// Dynamically dead while we have only 2 FP types.
Result = DAG.getNode(ISD::FP_EXTEND, Op.getValueType(), Result);
break;
case ISD::FP_ROUND:
case ISD::FP_TO_SINT:
case ISD::FP_TO_UINT:
Result = PromoteOp(Node->getOperand(0));
Result = DAG.getNode(Node->getOpcode(), Op.getValueType(), Result);
break;
case ISD::SINT_TO_FP:
Result = PromoteOp(Node->getOperand(0));
Result = DAG.getNode(ISD::SIGN_EXTEND_INREG, Result.getValueType(),
Result, Node->getOperand(0).getValueType());
Result = DAG.getNode(ISD::SINT_TO_FP, Op.getValueType(), Result);
break;
case ISD::UINT_TO_FP:
Result = PromoteOp(Node->getOperand(0));
Result = DAG.getZeroExtendInReg(Result,
Node->getOperand(0).getValueType());
Result = DAG.getNode(ISD::UINT_TO_FP, Op.getValueType(), Result);
break;
}
}
break;
case ISD::FP_ROUND_INREG:
case ISD::SIGN_EXTEND_INREG: {
Tmp1 = LegalizeOp(Node->getOperand(0));
MVT::ValueType ExtraVT = cast<MVTSDNode>(Node)->getExtraValueType();
// If this operation is not supported, convert it to a shl/shr or load/store
// pair.
switch (TLI.getOperationAction(Node->getOpcode(), ExtraVT)) {
default: assert(0 && "This action not supported for this op yet!");
case TargetLowering::Legal:
if (Tmp1 != Node->getOperand(0))
Result = DAG.getNode(Node->getOpcode(), Node->getValueType(0), Tmp1,
ExtraVT);
break;
case TargetLowering::Expand:
// If this is an integer extend and shifts are supported, do that.
if (Node->getOpcode() == 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.
unsigned BitsDiff = MVT::getSizeInBits(Node->getValueType(0)) -
MVT::getSizeInBits(ExtraVT);
SDOperand ShiftCst = DAG.getConstant(BitsDiff, TLI.getShiftAmountTy());
Result = DAG.getNode(ISD::SHL, Node->getValueType(0),
Node->getOperand(0), ShiftCst);
Result = DAG.getNode(ISD::SRA, Node->getValueType(0),
Result, ShiftCst);
} else if (Node->getOpcode() == ISD::FP_ROUND_INREG) {
// The only way we can lower this is to turn it into a STORETRUNC,
// 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.
const Type *Ty = MVT::getTypeForValueType(ExtraVT);
unsigned TySize = (unsigned)TLI.getTargetData().getTypeSize(Ty);
unsigned Align = TLI.getTargetData().getTypeAlignment(Ty);
MachineFunction &MF = DAG.getMachineFunction();
int SSFI =
MF.getFrameInfo()->CreateStackObject((unsigned)TySize, Align);
SDOperand StackSlot = DAG.getFrameIndex(SSFI, TLI.getPointerTy());
Result = DAG.getNode(ISD::TRUNCSTORE, MVT::Other, DAG.getEntryNode(),
Node->getOperand(0), StackSlot, ExtraVT);
Result = DAG.getNode(ISD::EXTLOAD, Node->getValueType(0),
Result, StackSlot, ExtraVT);
} else {
assert(0 && "Unknown op");
}
Result = LegalizeOp(Result);
break;
}
break;
}
}
if (!Op.Val->hasOneUse())
AddLegalizedOperand(Op, Result);
return Result;
}
/// PromoteOp - Given an operation that produces a value in an invalid type,
/// promote it to compute the value into a larger type. The produced value will
/// have the correct bits for the low portion of the register, but no guarantee
/// is made about the top bits: it may be zero, sign-extended, or garbage.
SDOperand SelectionDAGLegalize::PromoteOp(SDOperand Op) {
MVT::ValueType VT = Op.getValueType();
MVT::ValueType NVT = TLI.getTypeToTransformTo(VT);
assert(getTypeAction(VT) == Promote &&
"Caller should expand or legalize operands that are not promotable!");
assert(NVT > VT && MVT::isInteger(NVT) == MVT::isInteger(VT) &&
"Cannot promote to smaller type!");
std::map<SDOperand, SDOperand>::iterator I = PromotedNodes.find(Op);
if (I != PromotedNodes.end()) return I->second;
SDOperand Tmp1, Tmp2, Tmp3;
SDOperand Result;
SDNode *Node = Op.Val;
// Promotion needs an optimization step to clean up after it, and is not
// careful to avoid operations the target does not support. Make sure that
// all generated operations are legalized in the next iteration.
NeedsAnotherIteration = true;
switch (Node->getOpcode()) {
default:
std::cerr << "NODE: "; Node->dump(); std::cerr << "\n";
assert(0 && "Do not know how to promote this operator!");
abort();
case ISD::UNDEF:
Result = DAG.getNode(ISD::UNDEF, NVT);
break;
case ISD::Constant:
Result = DAG.getNode(ISD::ZERO_EXTEND, NVT, Op);
assert(isa<ConstantSDNode>(Result) && "Didn't constant fold zext?");
break;
case ISD::ConstantFP:
Result = DAG.getNode(ISD::FP_EXTEND, NVT, Op);
assert(isa<ConstantFPSDNode>(Result) && "Didn't constant fold fp_extend?");
break;
case ISD::CopyFromReg:
Result = DAG.getCopyFromReg(cast<RegSDNode>(Node)->getReg(), NVT,
Node->getOperand(0));
// Remember that we legalized the chain.
AddLegalizedOperand(Op.getValue(1), Result.getValue(1));
break;
case ISD::SETCC:
assert(getTypeAction(TLI.getSetCCResultTy()) == Legal &&
"SetCC type is not legal??");
Result = DAG.getSetCC(cast<SetCCSDNode>(Node)->getCondition(),
TLI.getSetCCResultTy(), Node->getOperand(0),
Node->getOperand(1));
Result = LegalizeOp(Result);
break;
case ISD::TRUNCATE:
switch (getTypeAction(Node->getOperand(0).getValueType())) {
case Legal:
Result = LegalizeOp(Node->getOperand(0));
assert(Result.getValueType() >= NVT &&
"This truncation doesn't make sense!");
if (Result.getValueType() > NVT) // Truncate to NVT instead of VT
Result = DAG.getNode(ISD::TRUNCATE, NVT, Result);
break;
case Promote:
// The truncation is not required, because we don't guarantee anything
// about high bits anyway.
Result = PromoteOp(Node->getOperand(0));
break;
case Expand:
ExpandOp(Node->getOperand(0), Tmp1, Tmp2);
// Truncate the low part of the expanded value to the result type
Result = DAG.getNode(ISD::TRUNCATE, VT, Tmp1);
}
break;
case ISD::SIGN_EXTEND:
case ISD::ZERO_EXTEND:
switch (getTypeAction(Node->getOperand(0).getValueType())) {
case Expand: assert(0 && "BUG: Smaller reg should have been promoted!");
case Legal:
// Input is legal? Just do extend all the way to the larger type.
Result = LegalizeOp(Node->getOperand(0));
Result = DAG.getNode(Node->getOpcode(), NVT, Result);
break;
case Promote:
// Promote the reg if it's smaller.
Result = PromoteOp(Node->getOperand(0));
// The high bits are not guaranteed to be anything. Insert an extend.
if (Node->getOpcode() == ISD::SIGN_EXTEND)
Result = DAG.getNode(ISD::SIGN_EXTEND_INREG, NVT, Result,
Node->getOperand(0).getValueType());
else
Result = DAG.getZeroExtendInReg(Result,
Node->getOperand(0).getValueType());
break;
}
break;
case ISD::FP_EXTEND:
assert(0 && "Case not implemented. Dynamically dead with 2 FP types!");
case ISD::FP_ROUND:
switch (getTypeAction(Node->getOperand(0).getValueType())) {
case Expand: assert(0 && "BUG: Cannot expand FP regs!");
case Promote: assert(0 && "Unreachable with 2 FP types!");
case Legal:
// Input is legal? Do an FP_ROUND_INREG.
Result = LegalizeOp(Node->getOperand(0));
Result = DAG.getNode(ISD::FP_ROUND_INREG, NVT, Result, VT);
break;
}
break;
case ISD::SINT_TO_FP:
case ISD::UINT_TO_FP:
switch (getTypeAction(Node->getOperand(0).getValueType())) {
case Legal:
Result = LegalizeOp(Node->getOperand(0));
// No extra round required here.
Result = DAG.getNode(Node->getOpcode(), NVT, Result);
break;
case Promote:
Result = PromoteOp(Node->getOperand(0));
if (Node->getOpcode() == ISD::SINT_TO_FP)
Result = DAG.getNode(ISD::SIGN_EXTEND_INREG, Result.getValueType(),
Result, Node->getOperand(0).getValueType());
else
Result = DAG.getZeroExtendInReg(Result,
Node->getOperand(0).getValueType());
// No extra round required here.
Result = DAG.getNode(Node->getOpcode(), NVT, Result);
break;
case Expand:
Result = ExpandIntToFP(Node->getOpcode() == ISD::SINT_TO_FP, NVT,
Node->getOperand(0));
Result = LegalizeOp(Result);
// Round if we cannot tolerate excess precision.
if (NoExcessFPPrecision)
Result = DAG.getNode(ISD::FP_ROUND_INREG, NVT, Result, VT);
break;
}
break;
case ISD::FP_TO_SINT:
case ISD::FP_TO_UINT:
switch (getTypeAction(Node->getOperand(0).getValueType())) {
case Legal:
Tmp1 = LegalizeOp(Node->getOperand(0));
break;
case Promote:
// The input result is prerounded, so we don't have to do anything
// special.
Tmp1 = PromoteOp(Node->getOperand(0));
break;
case Expand:
assert(0 && "not implemented");
}
Result = DAG.getNode(Node->getOpcode(), NVT, Tmp1);
break;
case ISD::FABS:
case ISD::FNEG:
Tmp1 = PromoteOp(Node->getOperand(0));
assert(Tmp1.getValueType() == NVT);
Result = DAG.getNode(Node->getOpcode(), NVT, Tmp1);
// NOTE: we do not have to do any extra rounding here for
// NoExcessFPPrecision, because we know the input will have the appropriate
// precision, and these operations don't modify precision at all.
break;
case ISD::AND:
case ISD::OR:
case ISD::XOR:
case ISD::ADD:
case ISD::SUB:
case ISD::MUL:
// The input may have strange things in the top bits of the registers, but
// these operations don't care. They may have wierd bits going out, but
// that too is okay if they are integer operations.
Tmp1 = PromoteOp(Node->getOperand(0));
Tmp2 = PromoteOp(Node->getOperand(1));
assert(Tmp1.getValueType() == NVT && Tmp2.getValueType() == NVT);
Result = DAG.getNode(Node->getOpcode(), NVT, Tmp1, Tmp2);
// However, if this is a floating point operation, they will give excess
// precision that we may not be able to tolerate. If we DO allow excess
// precision, just leave it, otherwise excise it.
// FIXME: Why would we need to round FP ops more than integer ones?
// Is Round(Add(Add(A,B),C)) != Round(Add(Round(Add(A,B)), C))
if (MVT::isFloatingPoint(NVT) && NoExcessFPPrecision)
Result = DAG.getNode(ISD::FP_ROUND_INREG, NVT, Result, VT);
break;
case ISD::SDIV:
case ISD::SREM:
// These operators require that their input be sign extended.
Tmp1 = PromoteOp(Node->getOperand(0));
Tmp2 = PromoteOp(Node->getOperand(1));
if (MVT::isInteger(NVT)) {
Tmp1 = DAG.getNode(ISD::SIGN_EXTEND_INREG, NVT, Tmp1, VT);
Tmp2 = DAG.getNode(ISD::SIGN_EXTEND_INREG, NVT, Tmp2, VT);
}
Result = DAG.getNode(Node->getOpcode(), NVT, Tmp1, Tmp2);
// Perform FP_ROUND: this is probably overly pessimistic.
if (MVT::isFloatingPoint(NVT) && NoExcessFPPrecision)
Result = DAG.getNode(ISD::FP_ROUND_INREG, NVT, Result, VT);
break;
case ISD::UDIV:
case ISD::UREM:
// These operators require that their input be zero extended.
Tmp1 = PromoteOp(Node->getOperand(0));
Tmp2 = PromoteOp(Node->getOperand(1));
assert(MVT::isInteger(NVT) && "Operators don't apply to FP!");
Tmp1 = DAG.getZeroExtendInReg(Tmp1, VT);
Tmp2 = DAG.getZeroExtendInReg(Tmp2, VT);
Result = DAG.getNode(Node->getOpcode(), NVT, Tmp1, Tmp2);
break;
case ISD::SHL:
Tmp1 = PromoteOp(Node->getOperand(0));
Tmp2 = LegalizeOp(Node->getOperand(1));
Result = DAG.getNode(ISD::SHL, NVT, Tmp1, Tmp2);
break;
case ISD::SRA:
// The input value must be properly sign extended.
Tmp1 = PromoteOp(Node->getOperand(0));
Tmp1 = DAG.getNode(ISD::SIGN_EXTEND_INREG, NVT, Tmp1, VT);
Tmp2 = LegalizeOp(Node->getOperand(1));
Result = DAG.getNode(ISD::SRA, NVT, Tmp1, Tmp2);
break;
case ISD::SRL:
// The input value must be properly zero extended.
Tmp1 = PromoteOp(Node->getOperand(0));
Tmp1 = DAG.getZeroExtendInReg(Tmp1, VT);
Tmp2 = LegalizeOp(Node->getOperand(1));
Result = DAG.getNode(ISD::SRL, NVT, Tmp1, Tmp2);
break;
case ISD::LOAD:
Tmp1 = LegalizeOp(Node->getOperand(0)); // Legalize the chain.
Tmp2 = LegalizeOp(Node->getOperand(1)); // Legalize the pointer.
// FIXME: When the DAG combiner exists, change this to use EXTLOAD!
if (MVT::isInteger(NVT))
Result = DAG.getNode(ISD::ZEXTLOAD, NVT, Tmp1, Tmp2, VT);
else
Result = DAG.getNode(ISD::EXTLOAD, NVT, Tmp1, Tmp2, VT);
// Remember that we legalized the chain.
AddLegalizedOperand(Op.getValue(1), Result.getValue(1));
break;
case ISD::SELECT:
switch (getTypeAction(Node->getOperand(0).getValueType())) {
case Expand: assert(0 && "It's impossible to expand bools");
case Legal:
Tmp1 = LegalizeOp(Node->getOperand(0));// Legalize the condition.
break;
case Promote:
Tmp1 = PromoteOp(Node->getOperand(0)); // Promote the condition.
break;
}
Tmp2 = PromoteOp(Node->getOperand(1)); // Legalize the op0
Tmp3 = PromoteOp(Node->getOperand(2)); // Legalize the op1
Result = DAG.getNode(ISD::SELECT, NVT, Tmp1, Tmp2, Tmp3);
break;
case ISD::CALL: {
Tmp1 = LegalizeOp(Node->getOperand(0)); // Legalize the chain.
Tmp2 = LegalizeOp(Node->getOperand(1)); // Legalize the callee.
std::vector<SDOperand> Ops;
for (unsigned i = 2, e = Node->getNumOperands(); i != e; ++i)
Ops.push_back(LegalizeOp(Node->getOperand(i)));
assert(Node->getNumValues() == 2 && Op.ResNo == 0 &&
"Can only promote single result calls");
std::vector<MVT::ValueType> RetTyVTs;
RetTyVTs.reserve(2);
RetTyVTs.push_back(NVT);
RetTyVTs.push_back(MVT::Other);
SDNode *NC = DAG.getCall(RetTyVTs, Tmp1, Tmp2, Ops);
Result = SDOperand(NC, 0);
// Insert the new chain mapping.
AddLegalizedOperand(Op.getValue(1), Result.getValue(1));
break;
}
}
assert(Result.Val && "Didn't set a result!");
AddPromotedOperand(Op, Result);
return Result;
}
/// ExpandAddSub - Find a clever way to expand this add operation into
/// subcomponents.
void SelectionDAGLegalize::
ExpandByParts(unsigned NodeOp, SDOperand LHS, SDOperand RHS,
SDOperand &Lo, SDOperand &Hi) {
// Expand the subcomponents.
SDOperand LHSL, LHSH, RHSL, RHSH;
ExpandOp(LHS, LHSL, LHSH);
ExpandOp(RHS, RHSL, RHSH);
// FIXME: this should be moved to the dag combiner someday.
if (NodeOp == ISD::ADD_PARTS || NodeOp == ISD::SUB_PARTS)
if (LHSL.getValueType() == MVT::i32) {
SDOperand LowEl;
if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(LHSL))
if (C->getValue() == 0)
LowEl = RHSL;
if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(RHSL))
if (C->getValue() == 0)
LowEl = LHSL;
if (LowEl.Val) {
// Turn this into an add/sub of the high part only.
SDOperand HiEl =
DAG.getNode(NodeOp == ISD::ADD_PARTS ? ISD::ADD : ISD::SUB,
LowEl.getValueType(), LHSH, RHSH);
Lo = LowEl;
Hi = HiEl;
return;
}
}
std::vector<SDOperand> Ops;
Ops.push_back(LHSL);
Ops.push_back(LHSH);
Ops.push_back(RHSL);
Ops.push_back(RHSH);
Lo = DAG.getNode(NodeOp, LHSL.getValueType(), Ops);
Hi = Lo.getValue(1);
}
void SelectionDAGLegalize::ExpandShiftParts(unsigned NodeOp,
SDOperand Op, SDOperand Amt,
SDOperand &Lo, SDOperand &Hi) {
// Expand the subcomponents.
SDOperand LHSL, LHSH;
ExpandOp(Op, LHSL, LHSH);
std::vector<SDOperand> Ops;
Ops.push_back(LHSL);
Ops.push_back(LHSH);
Ops.push_back(Amt);
Lo = DAG.getNode(NodeOp, LHSL.getValueType(), Ops);
Hi = Lo.getValue(1);
}
/// ExpandShift - Try to find a clever way to expand this shift operation out to
/// smaller elements. If we can't find a way that is more efficient than a
/// libcall on this target, return false. Otherwise, return true with the
/// low-parts expanded into Lo and Hi.
bool SelectionDAGLegalize::ExpandShift(unsigned Opc, SDOperand Op,SDOperand Amt,
SDOperand &Lo, SDOperand &Hi) {
assert((Opc == ISD::SHL || Opc == ISD::SRA || Opc == ISD::SRL) &&
"This is not a shift!");
MVT::ValueType NVT = TLI.getTypeToTransformTo(Op.getValueType());
SDOperand ShAmt = LegalizeOp(Amt);
MVT::ValueType ShTy = ShAmt.getValueType();
unsigned VTBits = MVT::getSizeInBits(Op.getValueType());
unsigned NVTBits = MVT::getSizeInBits(NVT);
// Handle the case when Amt is an immediate. Other cases are currently broken
// and are disabled.
if (ConstantSDNode *CN = dyn_cast<ConstantSDNode>(Amt.Val)) {
unsigned Cst = CN->getValue();
// Expand the incoming operand to be shifted, so that we have its parts
SDOperand InL, InH;
ExpandOp(Op, InL, InH);
switch(Opc) {
case ISD::SHL:
if (Cst > VTBits) {
Lo = DAG.getConstant(0, NVT);
Hi = DAG.getConstant(0, NVT);
} else if (Cst > NVTBits) {
Lo = DAG.getConstant(0, NVT);
Hi = DAG.getNode(ISD::SHL, NVT, InL, DAG.getConstant(Cst-NVTBits,ShTy));
} else if (Cst == NVTBits) {
Lo = DAG.getConstant(0, NVT);
Hi = InL;
} else {
Lo = DAG.getNode(ISD::SHL, NVT, InL, DAG.getConstant(Cst, ShTy));
Hi = DAG.getNode(ISD::OR, NVT,
DAG.getNode(ISD::SHL, NVT, InH, DAG.getConstant(Cst, ShTy)),
DAG.getNode(ISD::SRL, NVT, InL, DAG.getConstant(NVTBits-Cst, ShTy)));
}
return true;
case ISD::SRL:
if (Cst > VTBits) {
Lo = DAG.getConstant(0, NVT);
Hi = DAG.getConstant(0, NVT);
} else if (Cst > NVTBits) {
Lo = DAG.getNode(ISD::SRL, NVT, InH, DAG.getConstant(Cst-NVTBits,ShTy));
Hi = DAG.getConstant(0, NVT);
} else if (Cst == NVTBits) {
Lo = InH;
Hi = DAG.getConstant(0, NVT);
} else {
Lo = DAG.getNode(ISD::OR, NVT,
DAG.getNode(ISD::SRL, NVT, InL, DAG.getConstant(Cst, ShTy)),
DAG.getNode(ISD::SHL, NVT, InH, DAG.getConstant(NVTBits-Cst, ShTy)));
Hi = DAG.getNode(ISD::SRL, NVT, InH, DAG.getConstant(Cst, ShTy));
}
return true;
case ISD::SRA:
if (Cst > VTBits) {
Hi = Lo = DAG.getNode(ISD::SRA, NVT, InH,
DAG.getConstant(NVTBits-1, ShTy));
} else if (Cst > NVTBits) {
Lo = DAG.getNode(ISD::SRA, NVT, InH,
DAG.getConstant(Cst-NVTBits, ShTy));
Hi = DAG.getNode(ISD::SRA, NVT, InH,
DAG.getConstant(NVTBits-1, ShTy));
} else if (Cst == NVTBits) {
Lo = InH;
Hi = DAG.getNode(ISD::SRA, NVT, InH,
DAG.getConstant(NVTBits-1, ShTy));
} else {
Lo = DAG.getNode(ISD::OR, NVT,
DAG.getNode(ISD::SRL, NVT, InL, DAG.getConstant(Cst, ShTy)),
DAG.getNode(ISD::SHL, NVT, InH, DAG.getConstant(NVTBits-Cst, ShTy)));
Hi = DAG.getNode(ISD::SRA, NVT, InH, DAG.getConstant(Cst, ShTy));
}
return true;
}
}
// FIXME: The following code for expanding shifts using ISD::SELECT is buggy,
// so disable it for now. Currently targets are handling this via SHL_PARTS
// and friends.
return false;
// If we have an efficient select operation (or if the selects will all fold
// away), lower to some complex code, otherwise just emit the libcall.
if (TLI.getOperationAction(ISD::SELECT, NVT) != TargetLowering::Legal &&
!isa<ConstantSDNode>(Amt))
return false;
SDOperand InL, InH;
ExpandOp(Op, InL, InH);
SDOperand NAmt = DAG.getNode(ISD::SUB, ShTy, // NAmt = 32-ShAmt
DAG.getConstant(NVTBits, ShTy), ShAmt);
// Compare the unmasked shift amount against 32.
SDOperand Cond = DAG.getSetCC(ISD::SETGE, TLI.getSetCCResultTy(), ShAmt,
DAG.getConstant(NVTBits, ShTy));
if (TLI.getShiftAmountFlavor() != TargetLowering::Mask) {
ShAmt = DAG.getNode(ISD::AND, ShTy, ShAmt, // ShAmt &= 31
DAG.getConstant(NVTBits-1, ShTy));
NAmt = DAG.getNode(ISD::AND, ShTy, NAmt, // NAmt &= 31
DAG.getConstant(NVTBits-1, ShTy));
}
if (Opc == ISD::SHL) {
SDOperand T1 = DAG.getNode(ISD::OR, NVT,// T1 = (Hi << Amt) | (Lo >> NAmt)
DAG.getNode(ISD::SHL, NVT, InH, ShAmt),
DAG.getNode(ISD::SRL, NVT, InL, NAmt));
SDOperand T2 = DAG.getNode(ISD::SHL, NVT, InL, ShAmt); // T2 = Lo << Amt&31
Hi = DAG.getNode(ISD::SELECT, NVT, Cond, T2, T1);
Lo = DAG.getNode(ISD::SELECT, NVT, Cond, DAG.getConstant(0, NVT), T2);
} else {
SDOperand HiLoPart = DAG.getNode(ISD::SELECT, NVT,
DAG.getSetCC(ISD::SETEQ,
TLI.getSetCCResultTy(), NAmt,
DAG.getConstant(32, ShTy)),
DAG.getConstant(0, NVT),
DAG.getNode(ISD::SHL, NVT, InH, NAmt));
SDOperand T1 = DAG.getNode(ISD::OR, NVT,// T1 = (Hi << NAmt) | (Lo >> Amt)
HiLoPart,
DAG.getNode(ISD::SRL, NVT, InL, ShAmt));
SDOperand T2 = DAG.getNode(Opc, NVT, InH, ShAmt); // T2 = InH >> ShAmt&31
SDOperand HiPart;
if (Opc == ISD::SRA)
HiPart = DAG.getNode(ISD::SRA, NVT, InH,
DAG.getConstant(NVTBits-1, ShTy));
else
HiPart = DAG.getConstant(0, NVT);
Lo = DAG.getNode(ISD::SELECT, NVT, Cond, T2, T1);
Hi = DAG.getNode(ISD::SELECT, NVT, Cond, HiPart, T2);
}
return true;
}
/// FindLatestAdjCallStackDown - Scan up the dag to find the latest (highest
/// NodeDepth) node that is an AdjCallStackDown operation and occurs later than
/// Found.
static void FindLatestAdjCallStackDown(SDNode *Node, SDNode *&Found) {
if (Node->getNodeDepth() <= Found->getNodeDepth()) return;
// If we found an ADJCALLSTACKDOWN, we already know this node occurs later
// than the Found node. Just remember this node and return.
if (Node->getOpcode() == ISD::ADJCALLSTACKDOWN) {
Found = Node;
return;
}
// Otherwise, scan the operands of Node to see if any of them is a call.
assert(Node->getNumOperands() != 0 &&
"All leaves should have depth equal to the entry node!");
for (unsigned i = 0, e = Node->getNumOperands()-1; i != e; ++i)
FindLatestAdjCallStackDown(Node->getOperand(i).Val, Found);
// Tail recurse for the last iteration.
FindLatestAdjCallStackDown(Node->getOperand(Node->getNumOperands()-1).Val,
Found);
}
/// FindEarliestAdjCallStackUp - Scan down the dag to find the earliest (lowest
/// NodeDepth) node that is an AdjCallStackUp operation and occurs more recent
/// than Found.
static void FindEarliestAdjCallStackUp(SDNode *Node, SDNode *&Found) {
if (Found && Node->getNodeDepth() >= Found->getNodeDepth()) return;
// If we found an ADJCALLSTACKUP, we already know this node occurs earlier
// than the Found node. Just remember this node and return.
if (Node->getOpcode() == ISD::ADJCALLSTACKUP) {
Found = Node;
return;
}
// Otherwise, scan the operands of Node to see if any of them is a call.
SDNode::use_iterator UI = Node->use_begin(), E = Node->use_end();
if (UI == E) return;
for (--E; UI != E; ++UI)
FindEarliestAdjCallStackUp(*UI, Found);
// Tail recurse for the last iteration.
FindEarliestAdjCallStackUp(*UI, Found);
}
/// FindAdjCallStackUp - Given a chained node that is part of a call sequence,
/// find the ADJCALLSTACKUP node that terminates the call sequence.
static SDNode *FindAdjCallStackUp(SDNode *Node) {
if (Node->getOpcode() == ISD::ADJCALLSTACKUP)
return Node;
if (Node->use_empty())
return 0; // No adjcallstackup
if (Node->hasOneUse()) // Simple case, only has one user to check.
return FindAdjCallStackUp(*Node->use_begin());
SDOperand TheChain(Node, Node->getNumValues()-1);
assert(TheChain.getValueType() == MVT::Other && "Is not a token chain!");
for (SDNode::use_iterator UI = Node->use_begin(),
E = Node->use_end(); ; ++UI) {
assert(UI != E && "Didn't find a user of the tokchain, no ADJCALLSTACKUP!");
// 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)
return FindAdjCallStackUp(User);
}
assert(0 && "Unreachable");
abort();
}
/// FindInputOutputChains - If we are replacing an operation with a call we need
/// to find the call that occurs before and the call that occurs after it to
/// properly serialize the calls in the block.
static SDOperand FindInputOutputChains(SDNode *OpNode, SDNode *&OutChain,
SDOperand Entry) {
SDNode *LatestAdjCallStackDown = Entry.Val;
SDNode *LatestAdjCallStackUp = 0;
FindLatestAdjCallStackDown(OpNode, LatestAdjCallStackDown);
//std::cerr << "Found node: "; LatestAdjCallStackDown->dump(); std::cerr <<"\n";
// It is possible that no ISD::ADJCALLSTACKDOWN was found because there is no
// previous call in the function. LatestCallStackDown may in that case be
// the entry node itself. Do not attempt to find a matching ADJCALLSTACKUP
// unless LatestCallStackDown is an ADJCALLSTACKDOWN.
if (LatestAdjCallStackDown->getOpcode() == ISD::ADJCALLSTACKDOWN)
LatestAdjCallStackUp = FindAdjCallStackUp(LatestAdjCallStackDown);
else
LatestAdjCallStackUp = Entry.Val;
assert(LatestAdjCallStackUp && "NULL return from FindAdjCallStackUp");
SDNode *EarliestAdjCallStackUp = 0;
FindEarliestAdjCallStackUp(OpNode, EarliestAdjCallStackUp);
if (EarliestAdjCallStackUp) {
//std::cerr << "Found node: ";
//EarliestAdjCallStackUp->dump(); std::cerr <<"\n";
}
return SDOperand(LatestAdjCallStackUp, 0);
}
// 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.
SDOperand SelectionDAGLegalize::ExpandLibCall(const char *Name, SDNode *Node,
SDOperand &Hi) {
SDNode *OutChain;
SDOperand InChain = FindInputOutputChains(Node, OutChain,
DAG.getEntryNode());
if (InChain.Val == 0)
InChain = DAG.getEntryNode();
TargetLowering::ArgListTy Args;
for (unsigned i = 0, e = Node->getNumOperands(); i != e; ++i) {
MVT::ValueType ArgVT = Node->getOperand(i).getValueType();
const Type *ArgTy = MVT::getTypeForValueType(ArgVT);
Args.push_back(std::make_pair(Node->getOperand(i), ArgTy));
}
SDOperand Callee = DAG.getExternalSymbol(Name, TLI.getPointerTy());
// We don't care about token chains for libcalls. We just use the entry
// node as our input and ignore the output chain. This allows us to place
// calls wherever we need them to satisfy data dependences.
const Type *RetTy = MVT::getTypeForValueType(Node->getValueType(0));
SDOperand Result = TLI.LowerCallTo(InChain, RetTy, false, Callee,
Args, DAG).first;
switch (getTypeAction(Result.getValueType())) {
default: assert(0 && "Unknown thing");
case Legal:
return Result;
case Promote:
assert(0 && "Cannot promote this yet!");
case Expand:
SDOperand Lo;
ExpandOp(Result, Lo, Hi);
return Lo;
}
}
/// ExpandIntToFP - Expand a [US]INT_TO_FP operation, assuming that the
/// destination type is legal.
SDOperand SelectionDAGLegalize::
ExpandIntToFP(bool isSigned, MVT::ValueType DestTy, SDOperand Source) {
assert(getTypeAction(DestTy) == Legal && "Destination type is not legal!");
assert(getTypeAction(Source.getValueType()) == Expand &&
"This is not an expansion!");
assert(Source.getValueType() == MVT::i64 && "Only handle expand from i64!");
SDNode *OutChain;
SDOperand InChain = FindInputOutputChains(Source.Val, OutChain,
DAG.getEntryNode());
const char *FnName = 0;
if (isSigned) {
if (DestTy == MVT::f32)
FnName = "__floatdisf";
else {
assert(DestTy == MVT::f64 && "Unknown fp value type!");
FnName = "__floatdidf";
}
} else {
// If this is unsigned, and not supported, first perform the conversion to
// signed, then adjust the result if the sign bit is set.
SDOperand SignedConv = ExpandIntToFP(false, DestTy, Source);
assert(0 && "Unsigned casts not supported yet!");
}
SDOperand Callee = DAG.getExternalSymbol(FnName, TLI.getPointerTy());
TargetLowering::ArgListTy Args;
const Type *ArgTy = MVT::getTypeForValueType(Source.getValueType());
Args.push_back(std::make_pair(Source, ArgTy));
// We don't care about token chains for libcalls. We just use the entry
// node as our input and ignore the output chain. This allows us to place
// calls wherever we need them to satisfy data dependences.
const Type *RetTy = MVT::getTypeForValueType(DestTy);
return TLI.LowerCallTo(InChain, RetTy, false, Callee, Args, DAG).first;
}
/// ExpandOp - Expand the specified SDOperand into its two component pieces
/// Lo&Hi. Note that the Op MUST be an expanded type. As a result of this, the
/// LegalizeNodes map is filled in for any results that are not expanded, the
/// ExpandedNodes map is filled in for any results that are expanded, and the
/// Lo/Hi values are returned.
void SelectionDAGLegalize::ExpandOp(SDOperand Op, SDOperand &Lo, SDOperand &Hi){
MVT::ValueType VT = Op.getValueType();
MVT::ValueType NVT = TLI.getTypeToTransformTo(VT);
SDNode *Node = Op.Val;
assert(getTypeAction(VT) == Expand && "Not an expanded type!");
assert(MVT::isInteger(VT) && "Cannot expand FP values!");
assert(MVT::isInteger(NVT) && NVT < VT &&
"Cannot expand to FP value or to larger int value!");
// If there is more than one use of this, see if we already expanded it.
// There is no use remembering values that only have a single use, as the map
// entries will never be reused.
if (!Node->hasOneUse()) {
std::map<SDOperand, std::pair<SDOperand, SDOperand> >::iterator I
= ExpandedNodes.find(Op);
if (I != ExpandedNodes.end()) {
Lo = I->second.first;
Hi = I->second.second;
return;
}
}
// Expanding to multiple registers needs to perform an optimization step, and
// is not careful to avoid operations the target does not support. Make sure
// that all generated operations are legalized in the next iteration.
NeedsAnotherIteration = true;
switch (Node->getOpcode()) {
default:
std::cerr << "NODE: "; Node->dump(); std::cerr << "\n";
assert(0 && "Do not know how to expand this operator!");
abort();
case ISD::UNDEF:
Lo = DAG.getNode(ISD::UNDEF, NVT);
Hi = DAG.getNode(ISD::UNDEF, NVT);
break;
case ISD::Constant: {
uint64_t Cst = cast<ConstantSDNode>(Node)->getValue();
Lo = DAG.getConstant(Cst, NVT);
Hi = DAG.getConstant(Cst >> MVT::getSizeInBits(NVT), NVT);
break;
}
case ISD::CopyFromReg: {
unsigned Reg = cast<RegSDNode>(Node)->getReg();
// Aggregate register values are always in consequtive pairs.
Lo = DAG.getCopyFromReg(Reg, NVT, Node->getOperand(0));
Hi = DAG.getCopyFromReg(Reg+1, NVT, Lo.getValue(1));
// Remember that we legalized the chain.
AddLegalizedOperand(Op.getValue(1), Hi.getValue(1));
assert(isTypeLegal(NVT) && "Cannot expand this multiple times yet!");
break;
}
case ISD::BUILD_PAIR:
// Legalize both operands. FIXME: in the future we should handle the case
// where the two elements are not legal.
assert(isTypeLegal(NVT) && "Cannot expand this multiple times yet!");
Lo = LegalizeOp(Node->getOperand(0));
Hi = LegalizeOp(Node->getOperand(1));
break;
case ISD::LOAD: {
SDOperand Ch = LegalizeOp(Node->getOperand(0)); // Legalize the chain.
SDOperand Ptr = LegalizeOp(Node->getOperand(1)); // Legalize the pointer.
Lo = DAG.getLoad(NVT, Ch, Ptr);
// Increment the pointer to the other half.
unsigned IncrementSize = MVT::getSizeInBits(Lo.getValueType())/8;
Ptr = DAG.getNode(ISD::ADD, Ptr.getValueType(), Ptr,
getIntPtrConstant(IncrementSize));
Hi = DAG.getLoad(NVT, Ch, Ptr);
// Build a factor node to remember that this load is independent of the
// other one.
SDOperand TF = DAG.getNode(ISD::TokenFactor, MVT::Other, Lo.getValue(1),
Hi.getValue(1));
// Remember that we legalized the chain.
AddLegalizedOperand(Op.getValue(1), TF);
if (!TLI.isLittleEndian())
std::swap(Lo, Hi);
break;
}
case ISD::CALL: {
SDOperand Chain = LegalizeOp(Node->getOperand(0)); // Legalize the chain.
SDOperand Callee = LegalizeOp(Node->getOperand(1)); // Legalize the callee.
bool Changed = false;
std::vector<SDOperand> Ops;
for (unsigned i = 2, e = Node->getNumOperands(); i != e; ++i) {
Ops.push_back(LegalizeOp(Node->getOperand(i)));
Changed |= Ops.back() != Node->getOperand(i);
}
assert(Node->getNumValues() == 2 && Op.ResNo == 0 &&
"Can only expand a call once so far, not i64 -> i16!");
std::vector<MVT::ValueType> RetTyVTs;
RetTyVTs.reserve(3);
RetTyVTs.push_back(NVT);
RetTyVTs.push_back(NVT);
RetTyVTs.push_back(MVT::Other);
SDNode *NC = DAG.getCall(RetTyVTs, Chain, Callee, Ops);
Lo = SDOperand(NC, 0);
Hi = SDOperand(NC, 1);
// Insert the new chain mapping.
AddLegalizedOperand(Op.getValue(1), Hi.getValue(2));
break;
}
case ISD::AND:
case ISD::OR:
case ISD::XOR: { // Simple logical operators -> two trivial pieces.
SDOperand LL, LH, RL, RH;
ExpandOp(Node->getOperand(0), LL, LH);
ExpandOp(Node->getOperand(1), RL, RH);
Lo = DAG.getNode(Node->getOpcode(), NVT, LL, RL);
Hi = DAG.getNode(Node->getOpcode(), NVT, LH, RH);
break;
}
case ISD::SELECT: {
SDOperand C, LL, LH, RL, RH;
switch (getTypeAction(Node->getOperand(0).getValueType())) {
case Expand: assert(0 && "It's impossible to expand bools");
case Legal:
C = LegalizeOp(Node->getOperand(0)); // Legalize the condition.
break;
case Promote:
C = PromoteOp(Node->getOperand(0)); // Promote the condition.
break;
}
ExpandOp(Node->getOperand(1), LL, LH);
ExpandOp(Node->getOperand(2), RL, RH);
Lo = DAG.getNode(ISD::SELECT, NVT, C, LL, RL);
Hi = DAG.getNode(ISD::SELECT, NVT, C, LH, RH);
break;
}
case ISD::SIGN_EXTEND: {
SDOperand In;
switch (getTypeAction(Node->getOperand(0).getValueType())) {
case Expand: assert(0 && "expand-expand not implemented yet!");
case Legal: In = LegalizeOp(Node->getOperand(0)); break;
case Promote:
In = PromoteOp(Node->getOperand(0));
// Emit the appropriate sign_extend_inreg to get the value we want.
In = DAG.getNode(ISD::SIGN_EXTEND_INREG, In.getValueType(), In,
Node->getOperand(0).getValueType());
break;
}
// The low part is just a sign extension of the input (which degenerates to
// a copy).
Lo = DAG.getNode(ISD::SIGN_EXTEND, NVT, In);
// The high part is obtained by SRA'ing all but one of the bits of the lo
// part.
unsigned LoSize = MVT::getSizeInBits(Lo.getValueType());
Hi = DAG.getNode(ISD::SRA, NVT, Lo, DAG.getConstant(LoSize-1,
TLI.getShiftAmountTy()));
break;
}
case ISD::ZERO_EXTEND: {
SDOperand In;
switch (getTypeAction(Node->getOperand(0).getValueType())) {
case Expand: assert(0 && "expand-expand not implemented yet!");
case Legal: In = LegalizeOp(Node->getOperand(0)); break;
case Promote:
In = PromoteOp(Node->getOperand(0));
// Emit the appropriate zero_extend_inreg to get the value we want.
In = DAG.getZeroExtendInReg(In, Node->getOperand(0).getValueType());
break;
}
// The low part is just a zero extension of the input (which degenerates to
// a copy).
Lo = DAG.getNode(ISD::ZERO_EXTEND, NVT, In);
// The high part is just a zero.
Hi = DAG.getConstant(0, NVT);
break;
}
// These operators cannot be expanded directly, emit them as calls to
// library functions.
case ISD::FP_TO_SINT:
if (Node->getOperand(0).getValueType() == MVT::f32)
Lo = ExpandLibCall("__fixsfdi", Node, Hi);
else
Lo = ExpandLibCall("__fixdfdi", Node, Hi);
break;
case ISD::FP_TO_UINT:
if (Node->getOperand(0).getValueType() == MVT::f32)
Lo = ExpandLibCall("__fixunssfdi", Node, Hi);
else
Lo = ExpandLibCall("__fixunsdfdi", Node, Hi);
break;
case ISD::SHL:
// If we can emit an efficient shift operation, do so now.
if (ExpandShift(ISD::SHL, Node->getOperand(0), Node->getOperand(1), Lo, Hi))
break;
// If this target supports SHL_PARTS, use it.
if (TLI.getOperationAction(ISD::SHL_PARTS, NVT) == TargetLowering::Legal) {
ExpandShiftParts(ISD::SHL_PARTS, Node->getOperand(0), Node->getOperand(1),
Lo, Hi);
break;
}
// Otherwise, emit a libcall.
Lo = ExpandLibCall("__ashldi3", Node, Hi);
break;
case ISD::SRA:
// If we can emit an efficient shift operation, do so now.
if (ExpandShift(ISD::SRA, Node->getOperand(0), Node->getOperand(1), Lo, Hi))
break;
// If this target supports SRA_PARTS, use it.
if (TLI.getOperationAction(ISD::SRA_PARTS, NVT) == TargetLowering::Legal) {
ExpandShiftParts(ISD::SRA_PARTS, Node->getOperand(0), Node->getOperand(1),
Lo, Hi);
break;
}
// Otherwise, emit a libcall.
Lo = ExpandLibCall("__ashrdi3", Node, Hi);
break;
case ISD::SRL:
// If we can emit an efficient shift operation, do so now.
if (ExpandShift(ISD::SRL, Node->getOperand(0), Node->getOperand(1), Lo, Hi))
break;
// If this target supports SRL_PARTS, use it.
if (TLI.getOperationAction(ISD::SRL_PARTS, NVT) == TargetLowering::Legal) {
ExpandShiftParts(ISD::SRL_PARTS, Node->getOperand(0), Node->getOperand(1),
Lo, Hi);
break;
}
// Otherwise, emit a libcall.
Lo = ExpandLibCall("__lshrdi3", Node, Hi);
break;
case ISD::ADD:
ExpandByParts(ISD::ADD_PARTS, Node->getOperand(0), Node->getOperand(1),
Lo, Hi);
break;
case ISD::SUB:
ExpandByParts(ISD::SUB_PARTS, Node->getOperand(0), Node->getOperand(1),
Lo, Hi);
break;
case ISD::MUL: {
if (TLI.getOperationAction(ISD::MULHU, NVT) == TargetLowering::Legal) {
SDOperand LL, LH, RL, RH;
ExpandOp(Node->getOperand(0), LL, LH);
ExpandOp(Node->getOperand(1), RL, RH);
Hi = DAG.getNode(ISD::MULHU, NVT, LL, RL);
RH = DAG.getNode(ISD::MUL, NVT, LL, RH);
LH = DAG.getNode(ISD::MUL, NVT, LH, RL);
Hi = DAG.getNode(ISD::ADD, NVT, Hi, RH);
Hi = DAG.getNode(ISD::ADD, NVT, Hi, LH);
Lo = DAG.getNode(ISD::MUL, NVT, LL, RL);
} else {
Lo = ExpandLibCall("__muldi3" , Node, Hi); break;
}
break;
}
case ISD::SDIV: Lo = ExpandLibCall("__divdi3" , Node, Hi); break;
case ISD::UDIV: Lo = ExpandLibCall("__udivdi3", Node, Hi); break;
case ISD::SREM: Lo = ExpandLibCall("__moddi3" , Node, Hi); break;
case ISD::UREM: Lo = ExpandLibCall("__umoddi3", Node, Hi); break;
}
// Remember in a map if the values will be reused later.
if (!Node->hasOneUse()) {
bool isNew = ExpandedNodes.insert(std::make_pair(Op,
std::make_pair(Lo, Hi))).second;
assert(isNew && "Value already expanded?!?");
}
}
// SelectionDAG::Legalize - This is the entry point for the file.
//
void SelectionDAG::Legalize() {
/// run - This is the main entry point to this class.
///
SelectionDAGLegalize(*this).Run();
}