llvm-6502/lib/Target/Hexagon/HexagonISelLowering.cpp
Bill Wendling 4644d79871 Refactor function that checks that __builtin_returnaddress's argument is constant.
This moves the check up into the parent class so that all targets can use it
without having to copy (and keep in sync) the same error message.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198579 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-06 00:43:20 +00:00

1730 lines
66 KiB
C++

//===-- HexagonISelLowering.cpp - Hexagon DAG Lowering Implementation -----===//
//
// 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 interfaces that Hexagon uses to lower LLVM code
// into a selection DAG.
//
//===----------------------------------------------------------------------===//
#include "HexagonISelLowering.h"
#include "HexagonMachineFunctionInfo.h"
#include "HexagonSubtarget.h"
#include "HexagonTargetMachine.h"
#include "HexagonTargetObjectFile.h"
#include "llvm/CodeGen/CallingConvLower.h"
#include "llvm/CodeGen/MachineFrameInfo.h"
#include "llvm/CodeGen/MachineFunction.h"
#include "llvm/CodeGen/MachineInstrBuilder.h"
#include "llvm/CodeGen/MachineJumpTableInfo.h"
#include "llvm/CodeGen/MachineRegisterInfo.h"
#include "llvm/CodeGen/SelectionDAGISel.h"
#include "llvm/CodeGen/ValueTypes.h"
#include "llvm/IR/CallingConv.h"
#include "llvm/IR/DerivedTypes.h"
#include "llvm/IR/Function.h"
#include "llvm/IR/GlobalAlias.h"
#include "llvm/IR/GlobalVariable.h"
#include "llvm/IR/InlineAsm.h"
#include "llvm/IR/Intrinsics.h"
#include "llvm/IR/LLVMContext.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/raw_ostream.h"
using namespace llvm;
static cl::opt<bool>
EmitJumpTables("hexagon-emit-jump-tables", cl::init(true), cl::Hidden,
cl::desc("Control jump table emission on Hexagon target"));
namespace {
class HexagonCCState : public CCState {
int NumNamedVarArgParams;
public:
HexagonCCState(CallingConv::ID CC, bool isVarArg, MachineFunction &MF,
const TargetMachine &TM, SmallVectorImpl<CCValAssign> &locs,
LLVMContext &C, int NumNamedVarArgParams)
: CCState(CC, isVarArg, MF, TM, locs, C),
NumNamedVarArgParams(NumNamedVarArgParams) {}
int getNumNamedVarArgParams() const { return NumNamedVarArgParams; }
};
}
// Implement calling convention for Hexagon.
static bool
CC_Hexagon(unsigned ValNo, MVT ValVT,
MVT LocVT, CCValAssign::LocInfo LocInfo,
ISD::ArgFlagsTy ArgFlags, CCState &State);
static bool
CC_Hexagon32(unsigned ValNo, MVT ValVT,
MVT LocVT, CCValAssign::LocInfo LocInfo,
ISD::ArgFlagsTy ArgFlags, CCState &State);
static bool
CC_Hexagon64(unsigned ValNo, MVT ValVT,
MVT LocVT, CCValAssign::LocInfo LocInfo,
ISD::ArgFlagsTy ArgFlags, CCState &State);
static bool
RetCC_Hexagon(unsigned ValNo, MVT ValVT,
MVT LocVT, CCValAssign::LocInfo LocInfo,
ISD::ArgFlagsTy ArgFlags, CCState &State);
static bool
RetCC_Hexagon32(unsigned ValNo, MVT ValVT,
MVT LocVT, CCValAssign::LocInfo LocInfo,
ISD::ArgFlagsTy ArgFlags, CCState &State);
static bool
RetCC_Hexagon64(unsigned ValNo, MVT ValVT,
MVT LocVT, CCValAssign::LocInfo LocInfo,
ISD::ArgFlagsTy ArgFlags, CCState &State);
static bool
CC_Hexagon_VarArg (unsigned ValNo, MVT ValVT,
MVT LocVT, CCValAssign::LocInfo LocInfo,
ISD::ArgFlagsTy ArgFlags, CCState &State) {
HexagonCCState &HState = static_cast<HexagonCCState &>(State);
// NumNamedVarArgParams can not be zero for a VarArg function.
assert((HState.getNumNamedVarArgParams() > 0) &&
"NumNamedVarArgParams is not bigger than zero.");
if ((int)ValNo < HState.getNumNamedVarArgParams()) {
// Deal with named arguments.
return CC_Hexagon(ValNo, ValVT, LocVT, LocInfo, ArgFlags, State);
}
// Deal with un-named arguments.
unsigned ofst;
if (ArgFlags.isByVal()) {
// If pass-by-value, the size allocated on stack is decided
// by ArgFlags.getByValSize(), not by the size of LocVT.
assert ((ArgFlags.getByValSize() > 8) &&
"ByValSize must be bigger than 8 bytes");
ofst = State.AllocateStack(ArgFlags.getByValSize(), 4);
State.addLoc(CCValAssign::getMem(ValNo, ValVT, ofst, LocVT, LocInfo));
return false;
}
if (LocVT == MVT::i1 || LocVT == MVT::i8 || LocVT == MVT::i16) {
LocVT = MVT::i32;
ValVT = MVT::i32;
if (ArgFlags.isSExt())
LocInfo = CCValAssign::SExt;
else if (ArgFlags.isZExt())
LocInfo = CCValAssign::ZExt;
else
LocInfo = CCValAssign::AExt;
}
if (LocVT == MVT::i32 || LocVT == MVT::f32) {
ofst = State.AllocateStack(4, 4);
State.addLoc(CCValAssign::getMem(ValNo, ValVT, ofst, LocVT, LocInfo));
return false;
}
if (LocVT == MVT::i64 || LocVT == MVT::f64) {
ofst = State.AllocateStack(8, 8);
State.addLoc(CCValAssign::getMem(ValNo, ValVT, ofst, LocVT, LocInfo));
return false;
}
llvm_unreachable(0);
}
static bool
CC_Hexagon (unsigned ValNo, MVT ValVT,
MVT LocVT, CCValAssign::LocInfo LocInfo,
ISD::ArgFlagsTy ArgFlags, CCState &State) {
if (ArgFlags.isByVal()) {
// Passed on stack.
assert ((ArgFlags.getByValSize() > 8) &&
"ByValSize must be bigger than 8 bytes");
unsigned Offset = State.AllocateStack(ArgFlags.getByValSize(), 4);
State.addLoc(CCValAssign::getMem(ValNo, ValVT, Offset, LocVT, LocInfo));
return false;
}
if (LocVT == MVT::i1 || LocVT == MVT::i8 || LocVT == MVT::i16) {
LocVT = MVT::i32;
ValVT = MVT::i32;
if (ArgFlags.isSExt())
LocInfo = CCValAssign::SExt;
else if (ArgFlags.isZExt())
LocInfo = CCValAssign::ZExt;
else
LocInfo = CCValAssign::AExt;
}
if (LocVT == MVT::i32 || LocVT == MVT::f32) {
if (!CC_Hexagon32(ValNo, ValVT, LocVT, LocInfo, ArgFlags, State))
return false;
}
if (LocVT == MVT::i64 || LocVT == MVT::f64) {
if (!CC_Hexagon64(ValNo, ValVT, LocVT, LocInfo, ArgFlags, State))
return false;
}
return true; // CC didn't match.
}
static bool CC_Hexagon32(unsigned ValNo, MVT ValVT,
MVT LocVT, CCValAssign::LocInfo LocInfo,
ISD::ArgFlagsTy ArgFlags, CCState &State) {
static const uint16_t RegList[] = {
Hexagon::R0, Hexagon::R1, Hexagon::R2, Hexagon::R3, Hexagon::R4,
Hexagon::R5
};
if (unsigned Reg = State.AllocateReg(RegList, 6)) {
State.addLoc(CCValAssign::getReg(ValNo, ValVT, Reg, LocVT, LocInfo));
return false;
}
unsigned Offset = State.AllocateStack(4, 4);
State.addLoc(CCValAssign::getMem(ValNo, ValVT, Offset, LocVT, LocInfo));
return false;
}
static bool CC_Hexagon64(unsigned ValNo, MVT ValVT,
MVT LocVT, CCValAssign::LocInfo LocInfo,
ISD::ArgFlagsTy ArgFlags, CCState &State) {
if (unsigned Reg = State.AllocateReg(Hexagon::D0)) {
State.addLoc(CCValAssign::getReg(ValNo, ValVT, Reg, LocVT, LocInfo));
return false;
}
static const uint16_t RegList1[] = {
Hexagon::D1, Hexagon::D2
};
static const uint16_t RegList2[] = {
Hexagon::R1, Hexagon::R3
};
if (unsigned Reg = State.AllocateReg(RegList1, RegList2, 2)) {
State.addLoc(CCValAssign::getReg(ValNo, ValVT, Reg, LocVT, LocInfo));
return false;
}
unsigned Offset = State.AllocateStack(8, 8, Hexagon::D2);
State.addLoc(CCValAssign::getMem(ValNo, ValVT, Offset, LocVT, LocInfo));
return false;
}
static bool RetCC_Hexagon(unsigned ValNo, MVT ValVT,
MVT LocVT, CCValAssign::LocInfo LocInfo,
ISD::ArgFlagsTy ArgFlags, CCState &State) {
if (LocVT == MVT::i1 ||
LocVT == MVT::i8 ||
LocVT == MVT::i16) {
LocVT = MVT::i32;
ValVT = MVT::i32;
if (ArgFlags.isSExt())
LocInfo = CCValAssign::SExt;
else if (ArgFlags.isZExt())
LocInfo = CCValAssign::ZExt;
else
LocInfo = CCValAssign::AExt;
}
if (LocVT == MVT::i32 || LocVT == MVT::f32) {
if (!RetCC_Hexagon32(ValNo, ValVT, LocVT, LocInfo, ArgFlags, State))
return false;
}
if (LocVT == MVT::i64 || LocVT == MVT::f64) {
if (!RetCC_Hexagon64(ValNo, ValVT, LocVT, LocInfo, ArgFlags, State))
return false;
}
return true; // CC didn't match.
}
static bool RetCC_Hexagon32(unsigned ValNo, MVT ValVT,
MVT LocVT, CCValAssign::LocInfo LocInfo,
ISD::ArgFlagsTy ArgFlags, CCState &State) {
if (LocVT == MVT::i32 || LocVT == MVT::f32) {
if (unsigned Reg = State.AllocateReg(Hexagon::R0)) {
State.addLoc(CCValAssign::getReg(ValNo, ValVT, Reg, LocVT, LocInfo));
return false;
}
}
unsigned Offset = State.AllocateStack(4, 4);
State.addLoc(CCValAssign::getMem(ValNo, ValVT, Offset, LocVT, LocInfo));
return false;
}
static bool RetCC_Hexagon64(unsigned ValNo, MVT ValVT,
MVT LocVT, CCValAssign::LocInfo LocInfo,
ISD::ArgFlagsTy ArgFlags, CCState &State) {
if (LocVT == MVT::i64 || LocVT == MVT::f64) {
if (unsigned Reg = State.AllocateReg(Hexagon::D0)) {
State.addLoc(CCValAssign::getReg(ValNo, ValVT, Reg, LocVT, LocInfo));
return false;
}
}
unsigned Offset = State.AllocateStack(8, 8);
State.addLoc(CCValAssign::getMem(ValNo, ValVT, Offset, LocVT, LocInfo));
return false;
}
SDValue
HexagonTargetLowering::LowerINTRINSIC_WO_CHAIN(SDValue Op, SelectionDAG &DAG)
const {
return SDValue();
}
/// CreateCopyOfByValArgument - Make a copy of an aggregate at address specified
/// by "Src" to address "Dst" of size "Size". Alignment information is
/// specified by the specific parameter attribute. The copy will be passed as
/// a byval function parameter. Sometimes what we are copying is the end of a
/// larger object, the part that does not fit in registers.
static SDValue
CreateCopyOfByValArgument(SDValue Src, SDValue Dst, SDValue Chain,
ISD::ArgFlagsTy Flags, SelectionDAG &DAG,
SDLoc dl) {
SDValue SizeNode = DAG.getConstant(Flags.getByValSize(), MVT::i32);
return DAG.getMemcpy(Chain, dl, Dst, Src, SizeNode, Flags.getByValAlign(),
/*isVolatile=*/false, /*AlwaysInline=*/false,
MachinePointerInfo(), MachinePointerInfo());
}
// LowerReturn - Lower ISD::RET. If a struct is larger than 8 bytes and is
// passed by value, the function prototype is modified to return void and
// the value is stored in memory pointed by a pointer passed by caller.
SDValue
HexagonTargetLowering::LowerReturn(SDValue Chain,
CallingConv::ID CallConv, bool isVarArg,
const SmallVectorImpl<ISD::OutputArg> &Outs,
const SmallVectorImpl<SDValue> &OutVals,
SDLoc dl, SelectionDAG &DAG) const {
// CCValAssign - represent the assignment of the return value to locations.
SmallVector<CCValAssign, 16> RVLocs;
// CCState - Info about the registers and stack slot.
CCState CCInfo(CallConv, isVarArg, DAG.getMachineFunction(),
getTargetMachine(), RVLocs, *DAG.getContext());
// Analyze return values of ISD::RET
CCInfo.AnalyzeReturn(Outs, RetCC_Hexagon);
SDValue Flag;
SmallVector<SDValue, 4> RetOps(1, Chain);
// Copy the result values into the output registers.
for (unsigned i = 0; i != RVLocs.size(); ++i) {
CCValAssign &VA = RVLocs[i];
Chain = DAG.getCopyToReg(Chain, dl, VA.getLocReg(), OutVals[i], Flag);
// Guarantee that all emitted copies are stuck together with flags.
Flag = Chain.getValue(1);
RetOps.push_back(DAG.getRegister(VA.getLocReg(), VA.getLocVT()));
}
RetOps[0] = Chain; // Update chain.
// Add the flag if we have it.
if (Flag.getNode())
RetOps.push_back(Flag);
return DAG.getNode(HexagonISD::RET_FLAG, dl, MVT::Other,
&RetOps[0], RetOps.size());
}
/// LowerCallResult - Lower the result values of an ISD::CALL into the
/// appropriate copies out of appropriate physical registers. This assumes that
/// Chain/InFlag are the input chain/flag to use, and that TheCall is the call
/// being lowered. Returns a SDNode with the same number of values as the
/// ISD::CALL.
SDValue
HexagonTargetLowering::LowerCallResult(SDValue Chain, SDValue InFlag,
CallingConv::ID CallConv, bool isVarArg,
const
SmallVectorImpl<ISD::InputArg> &Ins,
SDLoc dl, SelectionDAG &DAG,
SmallVectorImpl<SDValue> &InVals,
const SmallVectorImpl<SDValue> &OutVals,
SDValue Callee) const {
// Assign locations to each value returned by this call.
SmallVector<CCValAssign, 16> RVLocs;
CCState CCInfo(CallConv, isVarArg, DAG.getMachineFunction(),
getTargetMachine(), RVLocs, *DAG.getContext());
CCInfo.AnalyzeCallResult(Ins, RetCC_Hexagon);
// Copy all of the result registers out of their specified physreg.
for (unsigned i = 0; i != RVLocs.size(); ++i) {
Chain = DAG.getCopyFromReg(Chain, dl,
RVLocs[i].getLocReg(),
RVLocs[i].getValVT(), InFlag).getValue(1);
InFlag = Chain.getValue(2);
InVals.push_back(Chain.getValue(0));
}
return Chain;
}
/// LowerCall - Functions arguments are copied from virtual regs to
/// (physical regs)/(stack frame), CALLSEQ_START and CALLSEQ_END are emitted.
SDValue
HexagonTargetLowering::LowerCall(TargetLowering::CallLoweringInfo &CLI,
SmallVectorImpl<SDValue> &InVals) const {
SelectionDAG &DAG = CLI.DAG;
SDLoc &dl = CLI.DL;
SmallVectorImpl<ISD::OutputArg> &Outs = CLI.Outs;
SmallVectorImpl<SDValue> &OutVals = CLI.OutVals;
SmallVectorImpl<ISD::InputArg> &Ins = CLI.Ins;
SDValue Chain = CLI.Chain;
SDValue Callee = CLI.Callee;
bool &isTailCall = CLI.IsTailCall;
CallingConv::ID CallConv = CLI.CallConv;
bool isVarArg = CLI.IsVarArg;
bool IsStructRet = (Outs.empty()) ? false : Outs[0].Flags.isSRet();
// Check for varargs.
int NumNamedVarArgParams = -1;
if (GlobalAddressSDNode *GA = dyn_cast<GlobalAddressSDNode>(Callee))
{
const Function* CalleeFn = NULL;
Callee = DAG.getTargetGlobalAddress(GA->getGlobal(), dl, MVT::i32);
if ((CalleeFn = dyn_cast<Function>(GA->getGlobal())))
{
// If a function has zero args and is a vararg function, that's
// disallowed so it must be an undeclared function. Do not assume
// varargs if the callee is undefined.
if (CalleeFn->isVarArg() &&
CalleeFn->getFunctionType()->getNumParams() != 0) {
NumNamedVarArgParams = CalleeFn->getFunctionType()->getNumParams();
}
}
}
// Analyze operands of the call, assigning locations to each operand.
SmallVector<CCValAssign, 16> ArgLocs;
HexagonCCState CCInfo(CallConv, isVarArg, DAG.getMachineFunction(),
getTargetMachine(), ArgLocs, *DAG.getContext(),
NumNamedVarArgParams);
if (NumNamedVarArgParams > 0)
CCInfo.AnalyzeCallOperands(Outs, CC_Hexagon_VarArg);
else
CCInfo.AnalyzeCallOperands(Outs, CC_Hexagon);
if(isTailCall) {
bool StructAttrFlag =
DAG.getMachineFunction().getFunction()->hasStructRetAttr();
isTailCall = IsEligibleForTailCallOptimization(Callee, CallConv,
isVarArg, IsStructRet,
StructAttrFlag,
Outs, OutVals, Ins, DAG);
for (unsigned i = 0, e = ArgLocs.size(); i != e; ++i){
CCValAssign &VA = ArgLocs[i];
if (VA.isMemLoc()) {
isTailCall = false;
break;
}
}
if (isTailCall) {
DEBUG(dbgs () << "Eligible for Tail Call\n");
} else {
DEBUG(dbgs () <<
"Argument must be passed on stack. Not eligible for Tail Call\n");
}
}
// Get a count of how many bytes are to be pushed on the stack.
unsigned NumBytes = CCInfo.getNextStackOffset();
SmallVector<std::pair<unsigned, SDValue>, 16> RegsToPass;
SmallVector<SDValue, 8> MemOpChains;
SDValue StackPtr =
DAG.getCopyFromReg(Chain, dl, TM.getRegisterInfo()->getStackRegister(),
getPointerTy());
// Walk the register/memloc assignments, inserting copies/loads.
for (unsigned i = 0, e = ArgLocs.size(); i != e; ++i) {
CCValAssign &VA = ArgLocs[i];
SDValue Arg = OutVals[i];
ISD::ArgFlagsTy Flags = Outs[i].Flags;
// Promote the value if needed.
switch (VA.getLocInfo()) {
default:
// Loc info must be one of Full, SExt, ZExt, or AExt.
llvm_unreachable("Unknown loc info!");
case CCValAssign::Full:
break;
case CCValAssign::SExt:
Arg = DAG.getNode(ISD::SIGN_EXTEND, dl, VA.getLocVT(), Arg);
break;
case CCValAssign::ZExt:
Arg = DAG.getNode(ISD::ZERO_EXTEND, dl, VA.getLocVT(), Arg);
break;
case CCValAssign::AExt:
Arg = DAG.getNode(ISD::ANY_EXTEND, dl, VA.getLocVT(), Arg);
break;
}
if (VA.isMemLoc()) {
unsigned LocMemOffset = VA.getLocMemOffset();
SDValue PtrOff = DAG.getConstant(LocMemOffset, StackPtr.getValueType());
PtrOff = DAG.getNode(ISD::ADD, dl, MVT::i32, StackPtr, PtrOff);
if (Flags.isByVal()) {
// The argument is a struct passed by value. According to LLVM, "Arg"
// is is pointer.
MemOpChains.push_back(CreateCopyOfByValArgument(Arg, PtrOff, Chain,
Flags, DAG, dl));
} else {
// The argument is not passed by value. "Arg" is a buildin type. It is
// not a pointer.
MemOpChains.push_back(DAG.getStore(Chain, dl, Arg, PtrOff,
MachinePointerInfo(),false, false,
0));
}
continue;
}
// Arguments that can be passed on register must be kept at RegsToPass
// vector.
if (VA.isRegLoc()) {
RegsToPass.push_back(std::make_pair(VA.getLocReg(), Arg));
}
}
// Transform all store nodes into one single node because all store
// nodes are independent of each other.
if (!MemOpChains.empty()) {
Chain = DAG.getNode(ISD::TokenFactor, dl, MVT::Other, &MemOpChains[0],
MemOpChains.size());
}
if (!isTailCall)
Chain = DAG.getCALLSEQ_START(Chain, DAG.getConstant(NumBytes,
getPointerTy(), true),
dl);
// Build a sequence of copy-to-reg nodes chained together with token
// chain and flag operands which copy the outgoing args into registers.
// The InFlag in necessary since all emitted instructions must be
// stuck together.
SDValue InFlag;
if (!isTailCall) {
for (unsigned i = 0, e = RegsToPass.size(); i != e; ++i) {
Chain = DAG.getCopyToReg(Chain, dl, RegsToPass[i].first,
RegsToPass[i].second, InFlag);
InFlag = Chain.getValue(1);
}
}
// For tail calls lower the arguments to the 'real' stack slot.
if (isTailCall) {
// Force all the incoming stack arguments to be loaded from the stack
// before any new outgoing arguments are stored to the stack, because the
// outgoing stack slots may alias the incoming argument stack slots, and
// the alias isn't otherwise explicit. This is slightly more conservative
// than necessary, because it means that each store effectively depends
// on every argument instead of just those arguments it would clobber.
//
// Do not flag preceding copytoreg stuff together with the following stuff.
InFlag = SDValue();
for (unsigned i = 0, e = RegsToPass.size(); i != e; ++i) {
Chain = DAG.getCopyToReg(Chain, dl, RegsToPass[i].first,
RegsToPass[i].second, InFlag);
InFlag = Chain.getValue(1);
}
InFlag =SDValue();
}
// If the callee is a GlobalAddress/ExternalSymbol node (quite common, every
// direct call is) turn it into a TargetGlobalAddress/TargetExternalSymbol
// node so that legalize doesn't hack it.
if (flag_aligned_memcpy) {
const char *MemcpyName =
"__hexagon_memcpy_likely_aligned_min32bytes_mult8bytes";
Callee =
DAG.getTargetExternalSymbol(MemcpyName, getPointerTy());
flag_aligned_memcpy = false;
} else if (GlobalAddressSDNode *G = dyn_cast<GlobalAddressSDNode>(Callee)) {
Callee = DAG.getTargetGlobalAddress(G->getGlobal(), dl, getPointerTy());
} else if (ExternalSymbolSDNode *S =
dyn_cast<ExternalSymbolSDNode>(Callee)) {
Callee = DAG.getTargetExternalSymbol(S->getSymbol(), getPointerTy());
}
// Returns a chain & a flag for retval copy to use.
SDVTList NodeTys = DAG.getVTList(MVT::Other, MVT::Glue);
SmallVector<SDValue, 8> Ops;
Ops.push_back(Chain);
Ops.push_back(Callee);
// Add argument registers to the end of the list so that they are
// known live into the call.
for (unsigned i = 0, e = RegsToPass.size(); i != e; ++i) {
Ops.push_back(DAG.getRegister(RegsToPass[i].first,
RegsToPass[i].second.getValueType()));
}
if (InFlag.getNode()) {
Ops.push_back(InFlag);
}
if (isTailCall)
return DAG.getNode(HexagonISD::TC_RETURN, dl, NodeTys, &Ops[0], Ops.size());
Chain = DAG.getNode(HexagonISD::CALL, dl, NodeTys, &Ops[0], Ops.size());
InFlag = Chain.getValue(1);
// Create the CALLSEQ_END node.
Chain = DAG.getCALLSEQ_END(Chain, DAG.getIntPtrConstant(NumBytes, true),
DAG.getIntPtrConstant(0, true), InFlag, dl);
InFlag = Chain.getValue(1);
// Handle result values, copying them out of physregs into vregs that we
// return.
return LowerCallResult(Chain, InFlag, CallConv, isVarArg, Ins, dl, DAG,
InVals, OutVals, Callee);
}
static bool getIndexedAddressParts(SDNode *Ptr, EVT VT,
bool isSEXTLoad, SDValue &Base,
SDValue &Offset, bool &isInc,
SelectionDAG &DAG) {
if (Ptr->getOpcode() != ISD::ADD)
return false;
if (VT == MVT::i64 || VT == MVT::i32 || VT == MVT::i16 || VT == MVT::i8) {
isInc = (Ptr->getOpcode() == ISD::ADD);
Base = Ptr->getOperand(0);
Offset = Ptr->getOperand(1);
// Ensure that Offset is a constant.
return (isa<ConstantSDNode>(Offset));
}
return false;
}
// TODO: Put this function along with the other isS* functions in
// HexagonISelDAGToDAG.cpp into a common file. Or better still, use the
// functions defined in HexagonOperands.td.
static bool Is_PostInc_S4_Offset(SDNode * S, int ShiftAmount) {
ConstantSDNode *N = cast<ConstantSDNode>(S);
// immS4 predicate - True if the immediate fits in a 4-bit sign extended.
// field.
int64_t v = (int64_t)N->getSExtValue();
int64_t m = 0;
if (ShiftAmount > 0) {
m = v % ShiftAmount;
v = v >> ShiftAmount;
}
return (v <= 7) && (v >= -8) && (m == 0);
}
/// getPostIndexedAddressParts - returns true by value, base pointer and
/// offset pointer and addressing mode by reference if this node can be
/// combined with a load / store to form a post-indexed load / store.
bool HexagonTargetLowering::getPostIndexedAddressParts(SDNode *N, SDNode *Op,
SDValue &Base,
SDValue &Offset,
ISD::MemIndexedMode &AM,
SelectionDAG &DAG) const
{
EVT VT;
SDValue Ptr;
bool isSEXTLoad = false;
if (LoadSDNode *LD = dyn_cast<LoadSDNode>(N)) {
VT = LD->getMemoryVT();
isSEXTLoad = LD->getExtensionType() == ISD::SEXTLOAD;
} else if (StoreSDNode *ST = dyn_cast<StoreSDNode>(N)) {
VT = ST->getMemoryVT();
if (ST->getValue().getValueType() == MVT::i64 && ST->isTruncatingStore()) {
return false;
}
} else {
return false;
}
bool isInc = false;
bool isLegal = getIndexedAddressParts(Op, VT, isSEXTLoad, Base, Offset,
isInc, DAG);
// ShiftAmount = number of left-shifted bits in the Hexagon instruction.
int ShiftAmount = VT.getSizeInBits() / 16;
if (isLegal && Is_PostInc_S4_Offset(Offset.getNode(), ShiftAmount)) {
AM = isInc ? ISD::POST_INC : ISD::POST_DEC;
return true;
}
return false;
}
SDValue HexagonTargetLowering::LowerINLINEASM(SDValue Op,
SelectionDAG &DAG) const {
SDNode *Node = Op.getNode();
MachineFunction &MF = DAG.getMachineFunction();
HexagonMachineFunctionInfo *FuncInfo =
MF.getInfo<HexagonMachineFunctionInfo>();
switch (Node->getOpcode()) {
case ISD::INLINEASM: {
unsigned NumOps = Node->getNumOperands();
if (Node->getOperand(NumOps-1).getValueType() == MVT::Glue)
--NumOps; // Ignore the flag operand.
for (unsigned i = InlineAsm::Op_FirstOperand; i != NumOps;) {
if (FuncInfo->hasClobberLR())
break;
unsigned Flags =
cast<ConstantSDNode>(Node->getOperand(i))->getZExtValue();
unsigned NumVals = InlineAsm::getNumOperandRegisters(Flags);
++i; // Skip the ID value.
switch (InlineAsm::getKind(Flags)) {
default: llvm_unreachable("Bad flags!");
case InlineAsm::Kind_RegDef:
case InlineAsm::Kind_RegUse:
case InlineAsm::Kind_Imm:
case InlineAsm::Kind_Clobber:
case InlineAsm::Kind_Mem: {
for (; NumVals; --NumVals, ++i) {}
break;
}
case InlineAsm::Kind_RegDefEarlyClobber: {
for (; NumVals; --NumVals, ++i) {
unsigned Reg =
cast<RegisterSDNode>(Node->getOperand(i))->getReg();
// Check it to be lr
if (Reg == TM.getRegisterInfo()->getRARegister()) {
FuncInfo->setHasClobberLR(true);
break;
}
}
break;
}
}
}
}
} // Node->getOpcode
return Op;
}
//
// Taken from the XCore backend.
//
SDValue HexagonTargetLowering::
LowerBR_JT(SDValue Op, SelectionDAG &DAG) const
{
SDValue Chain = Op.getOperand(0);
SDValue Table = Op.getOperand(1);
SDValue Index = Op.getOperand(2);
SDLoc dl(Op);
JumpTableSDNode *JT = cast<JumpTableSDNode>(Table);
unsigned JTI = JT->getIndex();
MachineFunction &MF = DAG.getMachineFunction();
const MachineJumpTableInfo *MJTI = MF.getJumpTableInfo();
SDValue TargetJT = DAG.getTargetJumpTable(JT->getIndex(), MVT::i32);
// Mark all jump table targets as address taken.
const std::vector<MachineJumpTableEntry> &JTE = MJTI->getJumpTables();
const std::vector<MachineBasicBlock*> &JTBBs = JTE[JTI].MBBs;
for (unsigned i = 0, e = JTBBs.size(); i != e; ++i) {
MachineBasicBlock *MBB = JTBBs[i];
MBB->setHasAddressTaken();
// This line is needed to set the hasAddressTaken flag on the BasicBlock
// object.
BlockAddress::get(const_cast<BasicBlock *>(MBB->getBasicBlock()));
}
SDValue JumpTableBase = DAG.getNode(HexagonISD::WrapperJT, dl,
getPointerTy(), TargetJT);
SDValue ShiftIndex = DAG.getNode(ISD::SHL, dl, MVT::i32, Index,
DAG.getConstant(2, MVT::i32));
SDValue JTAddress = DAG.getNode(ISD::ADD, dl, MVT::i32, JumpTableBase,
ShiftIndex);
SDValue LoadTarget = DAG.getLoad(MVT::i32, dl, Chain, JTAddress,
MachinePointerInfo(), false, false, false,
0);
return DAG.getNode(HexagonISD::BR_JT, dl, MVT::Other, Chain, LoadTarget);
}
SDValue
HexagonTargetLowering::LowerDYNAMIC_STACKALLOC(SDValue Op,
SelectionDAG &DAG) const {
SDValue Chain = Op.getOperand(0);
SDValue Size = Op.getOperand(1);
SDLoc dl(Op);
unsigned SPReg = getStackPointerRegisterToSaveRestore();
// Get a reference to the stack pointer.
SDValue StackPointer = DAG.getCopyFromReg(Chain, dl, SPReg, MVT::i32);
// Subtract the dynamic size from the actual stack size to
// obtain the new stack size.
SDValue Sub = DAG.getNode(ISD::SUB, dl, MVT::i32, StackPointer, Size);
//
// For Hexagon, the outgoing memory arguments area should be on top of the
// alloca area on the stack i.e., the outgoing memory arguments should be
// at a lower address than the alloca area. Move the alloca area down the
// stack by adding back the space reserved for outgoing arguments to SP
// here.
//
// We do not know what the size of the outgoing args is at this point.
// So, we add a pseudo instruction ADJDYNALLOC that will adjust the
// stack pointer. We patch this instruction with the correct, known
// offset in emitPrologue().
//
// Use a placeholder immediate (zero) for now. This will be patched up
// by emitPrologue().
SDValue ArgAdjust = DAG.getNode(HexagonISD::ADJDYNALLOC, dl,
MVT::i32,
Sub,
DAG.getConstant(0, MVT::i32));
// The Sub result contains the new stack start address, so it
// must be placed in the stack pointer register.
SDValue CopyChain = DAG.getCopyToReg(Chain, dl,
TM.getRegisterInfo()->getStackRegister(),
Sub);
SDValue Ops[2] = { ArgAdjust, CopyChain };
return DAG.getMergeValues(Ops, 2, dl);
}
SDValue
HexagonTargetLowering::LowerFormalArguments(SDValue Chain,
CallingConv::ID CallConv,
bool isVarArg,
const
SmallVectorImpl<ISD::InputArg> &Ins,
SDLoc dl, SelectionDAG &DAG,
SmallVectorImpl<SDValue> &InVals)
const {
MachineFunction &MF = DAG.getMachineFunction();
MachineFrameInfo *MFI = MF.getFrameInfo();
MachineRegisterInfo &RegInfo = MF.getRegInfo();
HexagonMachineFunctionInfo *FuncInfo =
MF.getInfo<HexagonMachineFunctionInfo>();
// Assign locations to all of the incoming arguments.
SmallVector<CCValAssign, 16> ArgLocs;
CCState CCInfo(CallConv, isVarArg, DAG.getMachineFunction(),
getTargetMachine(), ArgLocs, *DAG.getContext());
CCInfo.AnalyzeFormalArguments(Ins, CC_Hexagon);
// For LLVM, in the case when returning a struct by value (>8byte),
// the first argument is a pointer that points to the location on caller's
// stack where the return value will be stored. For Hexagon, the location on
// caller's stack is passed only when the struct size is smaller than (and
// equal to) 8 bytes. If not, no address will be passed into callee and
// callee return the result direclty through R0/R1.
SmallVector<SDValue, 4> MemOps;
for (unsigned i = 0, e = ArgLocs.size(); i != e; ++i) {
CCValAssign &VA = ArgLocs[i];
ISD::ArgFlagsTy Flags = Ins[i].Flags;
unsigned ObjSize;
unsigned StackLocation;
int FI;
if ( (VA.isRegLoc() && !Flags.isByVal())
|| (VA.isRegLoc() && Flags.isByVal() && Flags.getByValSize() > 8)) {
// Arguments passed in registers
// 1. int, long long, ptr args that get allocated in register.
// 2. Large struct that gets an register to put its address in.
EVT RegVT = VA.getLocVT();
if (RegVT == MVT::i8 || RegVT == MVT::i16 ||
RegVT == MVT::i32 || RegVT == MVT::f32) {
unsigned VReg =
RegInfo.createVirtualRegister(&Hexagon::IntRegsRegClass);
RegInfo.addLiveIn(VA.getLocReg(), VReg);
InVals.push_back(DAG.getCopyFromReg(Chain, dl, VReg, RegVT));
} else if (RegVT == MVT::i64) {
unsigned VReg =
RegInfo.createVirtualRegister(&Hexagon::DoubleRegsRegClass);
RegInfo.addLiveIn(VA.getLocReg(), VReg);
InVals.push_back(DAG.getCopyFromReg(Chain, dl, VReg, RegVT));
} else {
assert (0);
}
} else if (VA.isRegLoc() && Flags.isByVal() && Flags.getByValSize() <= 8) {
assert (0 && "ByValSize must be bigger than 8 bytes");
} else {
// Sanity check.
assert(VA.isMemLoc());
if (Flags.isByVal()) {
// If it's a byval parameter, then we need to compute the
// "real" size, not the size of the pointer.
ObjSize = Flags.getByValSize();
} else {
ObjSize = VA.getLocVT().getStoreSizeInBits() >> 3;
}
StackLocation = HEXAGON_LRFP_SIZE + VA.getLocMemOffset();
// Create the frame index object for this incoming parameter...
FI = MFI->CreateFixedObject(ObjSize, StackLocation, true);
// Create the SelectionDAG nodes cordl, responding to a load
// from this parameter.
SDValue FIN = DAG.getFrameIndex(FI, MVT::i32);
if (Flags.isByVal()) {
// If it's a pass-by-value aggregate, then do not dereference the stack
// location. Instead, we should generate a reference to the stack
// location.
InVals.push_back(FIN);
} else {
InVals.push_back(DAG.getLoad(VA.getLocVT(), dl, Chain, FIN,
MachinePointerInfo(), false, false,
false, 0));
}
}
}
if (!MemOps.empty())
Chain = DAG.getNode(ISD::TokenFactor, dl, MVT::Other, &MemOps[0],
MemOps.size());
if (isVarArg) {
// This will point to the next argument passed via stack.
int FrameIndex = MFI->CreateFixedObject(Hexagon_PointerSize,
HEXAGON_LRFP_SIZE +
CCInfo.getNextStackOffset(),
true);
FuncInfo->setVarArgsFrameIndex(FrameIndex);
}
return Chain;
}
SDValue
HexagonTargetLowering::LowerVASTART(SDValue Op, SelectionDAG &DAG) const {
// VASTART stores the address of the VarArgsFrameIndex slot into the
// memory location argument.
MachineFunction &MF = DAG.getMachineFunction();
HexagonMachineFunctionInfo *QFI = MF.getInfo<HexagonMachineFunctionInfo>();
SDValue Addr = DAG.getFrameIndex(QFI->getVarArgsFrameIndex(), MVT::i32);
const Value *SV = cast<SrcValueSDNode>(Op.getOperand(2))->getValue();
return DAG.getStore(Op.getOperand(0), SDLoc(Op), Addr,
Op.getOperand(1), MachinePointerInfo(SV), false,
false, 0);
}
SDValue
HexagonTargetLowering::LowerSELECT_CC(SDValue Op, SelectionDAG &DAG) const {
SDValue LHS = Op.getOperand(0);
SDValue RHS = Op.getOperand(1);
SDValue CC = Op.getOperand(4);
SDValue TrueVal = Op.getOperand(2);
SDValue FalseVal = Op.getOperand(3);
SDLoc dl(Op);
SDNode* OpNode = Op.getNode();
EVT SVT = OpNode->getValueType(0);
SDValue Cond = DAG.getNode(ISD::SETCC, dl, MVT::i1, LHS, RHS, CC);
return DAG.getNode(ISD::SELECT, dl, SVT, Cond, TrueVal, FalseVal);
}
SDValue
HexagonTargetLowering::LowerConstantPool(SDValue Op, SelectionDAG &DAG) const {
EVT ValTy = Op.getValueType();
SDLoc dl(Op);
ConstantPoolSDNode *CP = cast<ConstantPoolSDNode>(Op);
SDValue Res;
if (CP->isMachineConstantPoolEntry())
Res = DAG.getTargetConstantPool(CP->getMachineCPVal(), ValTy,
CP->getAlignment());
else
Res = DAG.getTargetConstantPool(CP->getConstVal(), ValTy,
CP->getAlignment());
return DAG.getNode(HexagonISD::CONST32, dl, ValTy, Res);
}
SDValue
HexagonTargetLowering::LowerRETURNADDR(SDValue Op, SelectionDAG &DAG) const {
const TargetRegisterInfo *TRI = TM.getRegisterInfo();
MachineFunction &MF = DAG.getMachineFunction();
MachineFrameInfo *MFI = MF.getFrameInfo();
MFI->setReturnAddressIsTaken(true);
if (verifyReturnAddressArgumentIsConstant(Op, DAG))
return SDValue();
EVT VT = Op.getValueType();
SDLoc dl(Op);
unsigned Depth = cast<ConstantSDNode>(Op.getOperand(0))->getZExtValue();
if (Depth) {
SDValue FrameAddr = LowerFRAMEADDR(Op, DAG);
SDValue Offset = DAG.getConstant(4, MVT::i32);
return DAG.getLoad(VT, dl, DAG.getEntryNode(),
DAG.getNode(ISD::ADD, dl, VT, FrameAddr, Offset),
MachinePointerInfo(), false, false, false, 0);
}
// Return LR, which contains the return address. Mark it an implicit live-in.
unsigned Reg = MF.addLiveIn(TRI->getRARegister(), getRegClassFor(MVT::i32));
return DAG.getCopyFromReg(DAG.getEntryNode(), dl, Reg, VT);
}
SDValue
HexagonTargetLowering::LowerFRAMEADDR(SDValue Op, SelectionDAG &DAG) const {
const HexagonRegisterInfo *TRI = TM.getRegisterInfo();
MachineFrameInfo *MFI = DAG.getMachineFunction().getFrameInfo();
MFI->setFrameAddressIsTaken(true);
EVT VT = Op.getValueType();
SDLoc dl(Op);
unsigned Depth = cast<ConstantSDNode>(Op.getOperand(0))->getZExtValue();
SDValue FrameAddr = DAG.getCopyFromReg(DAG.getEntryNode(), dl,
TRI->getFrameRegister(), VT);
while (Depth--)
FrameAddr = DAG.getLoad(VT, dl, DAG.getEntryNode(), FrameAddr,
MachinePointerInfo(),
false, false, false, 0);
return FrameAddr;
}
SDValue HexagonTargetLowering::LowerATOMIC_FENCE(SDValue Op,
SelectionDAG& DAG) const {
SDLoc dl(Op);
return DAG.getNode(HexagonISD::BARRIER, dl, MVT::Other, Op.getOperand(0));
}
SDValue HexagonTargetLowering::LowerGLOBALADDRESS(SDValue Op,
SelectionDAG &DAG) const {
SDValue Result;
const GlobalValue *GV = cast<GlobalAddressSDNode>(Op)->getGlobal();
int64_t Offset = cast<GlobalAddressSDNode>(Op)->getOffset();
SDLoc dl(Op);
Result = DAG.getTargetGlobalAddress(GV, dl, getPointerTy(), Offset);
const HexagonTargetObjectFile &TLOF =
static_cast<const HexagonTargetObjectFile &>(getObjFileLowering());
if (TLOF.IsGlobalInSmallSection(GV, getTargetMachine())) {
return DAG.getNode(HexagonISD::CONST32_GP, dl, getPointerTy(), Result);
}
return DAG.getNode(HexagonISD::CONST32, dl, getPointerTy(), Result);
}
SDValue
HexagonTargetLowering::LowerBlockAddress(SDValue Op, SelectionDAG &DAG) const {
const BlockAddress *BA = cast<BlockAddressSDNode>(Op)->getBlockAddress();
SDValue BA_SD = DAG.getTargetBlockAddress(BA, MVT::i32);
SDLoc dl(Op);
return DAG.getNode(HexagonISD::CONST32_GP, dl, getPointerTy(), BA_SD);
}
//===----------------------------------------------------------------------===//
// TargetLowering Implementation
//===----------------------------------------------------------------------===//
HexagonTargetLowering::HexagonTargetLowering(HexagonTargetMachine
&targetmachine)
: TargetLowering(targetmachine, new HexagonTargetObjectFile()),
TM(targetmachine) {
const HexagonRegisterInfo* QRI = TM.getRegisterInfo();
// Set up the register classes.
addRegisterClass(MVT::i32, &Hexagon::IntRegsRegClass);
addRegisterClass(MVT::i64, &Hexagon::DoubleRegsRegClass);
if (QRI->Subtarget.hasV5TOps()) {
addRegisterClass(MVT::f32, &Hexagon::IntRegsRegClass);
addRegisterClass(MVT::f64, &Hexagon::DoubleRegsRegClass);
}
addRegisterClass(MVT::i1, &Hexagon::PredRegsRegClass);
computeRegisterProperties();
// Align loop entry
setPrefLoopAlignment(4);
// Limits for inline expansion of memcpy/memmove
MaxStoresPerMemcpy = 6;
MaxStoresPerMemmove = 6;
//
// Library calls for unsupported operations
//
setLibcallName(RTLIB::SINTTOFP_I128_F64, "__hexagon_floattidf");
setLibcallName(RTLIB::SINTTOFP_I128_F32, "__hexagon_floattisf");
setLibcallName(RTLIB::FPTOUINT_F32_I128, "__hexagon_fixunssfti");
setLibcallName(RTLIB::FPTOUINT_F64_I128, "__hexagon_fixunsdfti");
setLibcallName(RTLIB::FPTOSINT_F32_I128, "__hexagon_fixsfti");
setLibcallName(RTLIB::FPTOSINT_F64_I128, "__hexagon_fixdfti");
setLibcallName(RTLIB::SDIV_I32, "__hexagon_divsi3");
setOperationAction(ISD::SDIV, MVT::i32, Expand);
setLibcallName(RTLIB::SREM_I32, "__hexagon_umodsi3");
setOperationAction(ISD::SREM, MVT::i32, Expand);
setLibcallName(RTLIB::SDIV_I64, "__hexagon_divdi3");
setOperationAction(ISD::SDIV, MVT::i64, Expand);
setLibcallName(RTLIB::SREM_I64, "__hexagon_moddi3");
setOperationAction(ISD::SREM, MVT::i64, Expand);
setLibcallName(RTLIB::UDIV_I32, "__hexagon_udivsi3");
setOperationAction(ISD::UDIV, MVT::i32, Expand);
setLibcallName(RTLIB::UDIV_I64, "__hexagon_udivdi3");
setOperationAction(ISD::UDIV, MVT::i64, Expand);
setLibcallName(RTLIB::UREM_I32, "__hexagon_umodsi3");
setOperationAction(ISD::UREM, MVT::i32, Expand);
setLibcallName(RTLIB::UREM_I64, "__hexagon_umoddi3");
setOperationAction(ISD::UREM, MVT::i64, Expand);
setLibcallName(RTLIB::DIV_F32, "__hexagon_divsf3");
setOperationAction(ISD::FDIV, MVT::f32, Expand);
setLibcallName(RTLIB::DIV_F64, "__hexagon_divdf3");
setOperationAction(ISD::FDIV, MVT::f64, Expand);
setOperationAction(ISD::FSQRT, MVT::f32, Expand);
setOperationAction(ISD::FSQRT, MVT::f64, Expand);
setOperationAction(ISD::FSIN, MVT::f32, Expand);
setOperationAction(ISD::FSIN, MVT::f64, Expand);
if (QRI->Subtarget.hasV5TOps()) {
// Hexagon V5 Support.
setOperationAction(ISD::FADD, MVT::f32, Legal);
setOperationAction(ISD::FADD, MVT::f64, Legal);
setOperationAction(ISD::FP_EXTEND, MVT::f32, Legal);
setCondCodeAction(ISD::SETOEQ, MVT::f32, Legal);
setCondCodeAction(ISD::SETOEQ, MVT::f64, Legal);
setCondCodeAction(ISD::SETUEQ, MVT::f32, Legal);
setCondCodeAction(ISD::SETUEQ, MVT::f64, Legal);
setCondCodeAction(ISD::SETOGE, MVT::f32, Legal);
setCondCodeAction(ISD::SETOGE, MVT::f64, Legal);
setCondCodeAction(ISD::SETUGE, MVT::f32, Legal);
setCondCodeAction(ISD::SETUGE, MVT::f64, Legal);
setCondCodeAction(ISD::SETOGT, MVT::f32, Legal);
setCondCodeAction(ISD::SETOGT, MVT::f64, Legal);
setCondCodeAction(ISD::SETUGT, MVT::f32, Legal);
setCondCodeAction(ISD::SETUGT, MVT::f64, Legal);
setCondCodeAction(ISD::SETOLE, MVT::f32, Legal);
setCondCodeAction(ISD::SETOLE, MVT::f64, Legal);
setCondCodeAction(ISD::SETOLT, MVT::f32, Legal);
setCondCodeAction(ISD::SETOLT, MVT::f64, Legal);
setOperationAction(ISD::ConstantFP, MVT::f32, Legal);
setOperationAction(ISD::ConstantFP, MVT::f64, Legal);
setOperationAction(ISD::FP_TO_UINT, MVT::i1, Promote);
setOperationAction(ISD::FP_TO_SINT, MVT::i1, Promote);
setOperationAction(ISD::UINT_TO_FP, MVT::i1, Promote);
setOperationAction(ISD::SINT_TO_FP, MVT::i1, Promote);
setOperationAction(ISD::FP_TO_UINT, MVT::i8, Promote);
setOperationAction(ISD::FP_TO_SINT, MVT::i8, Promote);
setOperationAction(ISD::UINT_TO_FP, MVT::i8, Promote);
setOperationAction(ISD::SINT_TO_FP, MVT::i8, Promote);
setOperationAction(ISD::FP_TO_UINT, MVT::i16, Promote);
setOperationAction(ISD::FP_TO_SINT, MVT::i16, Promote);
setOperationAction(ISD::UINT_TO_FP, MVT::i16, Promote);
setOperationAction(ISD::SINT_TO_FP, MVT::i16, Promote);
setOperationAction(ISD::FP_TO_UINT, MVT::i32, Legal);
setOperationAction(ISD::FP_TO_SINT, MVT::i32, Legal);
setOperationAction(ISD::UINT_TO_FP, MVT::i32, Legal);
setOperationAction(ISD::SINT_TO_FP, MVT::i32, Legal);
setOperationAction(ISD::FP_TO_UINT, MVT::i64, Legal);
setOperationAction(ISD::FP_TO_SINT, MVT::i64, Legal);
setOperationAction(ISD::UINT_TO_FP, MVT::i64, Legal);
setOperationAction(ISD::SINT_TO_FP, MVT::i64, Legal);
setOperationAction(ISD::FABS, MVT::f32, Legal);
setOperationAction(ISD::FABS, MVT::f64, Expand);
setOperationAction(ISD::FNEG, MVT::f32, Legal);
setOperationAction(ISD::FNEG, MVT::f64, Expand);
} else {
// Expand fp<->uint.
setOperationAction(ISD::FP_TO_SINT, MVT::i32, Expand);
setOperationAction(ISD::FP_TO_UINT, MVT::i32, Expand);
setOperationAction(ISD::SINT_TO_FP, MVT::i32, Expand);
setOperationAction(ISD::UINT_TO_FP, MVT::i32, Expand);
setLibcallName(RTLIB::SINTTOFP_I64_F32, "__hexagon_floatdisf");
setLibcallName(RTLIB::UINTTOFP_I64_F32, "__hexagon_floatundisf");
setLibcallName(RTLIB::UINTTOFP_I32_F32, "__hexagon_floatunsisf");
setLibcallName(RTLIB::SINTTOFP_I32_F32, "__hexagon_floatsisf");
setLibcallName(RTLIB::SINTTOFP_I64_F64, "__hexagon_floatdidf");
setLibcallName(RTLIB::UINTTOFP_I64_F64, "__hexagon_floatundidf");
setLibcallName(RTLIB::UINTTOFP_I32_F64, "__hexagon_floatunsidf");
setLibcallName(RTLIB::SINTTOFP_I32_F64, "__hexagon_floatsidf");
setLibcallName(RTLIB::FPTOUINT_F32_I32, "__hexagon_fixunssfsi");
setLibcallName(RTLIB::FPTOUINT_F32_I64, "__hexagon_fixunssfdi");
setLibcallName(RTLIB::FPTOSINT_F64_I64, "__hexagon_fixdfdi");
setLibcallName(RTLIB::FPTOSINT_F32_I64, "__hexagon_fixsfdi");
setLibcallName(RTLIB::FPTOUINT_F64_I32, "__hexagon_fixunsdfsi");
setLibcallName(RTLIB::FPTOUINT_F64_I64, "__hexagon_fixunsdfdi");
setLibcallName(RTLIB::ADD_F64, "__hexagon_adddf3");
setOperationAction(ISD::FADD, MVT::f64, Expand);
setLibcallName(RTLIB::ADD_F32, "__hexagon_addsf3");
setOperationAction(ISD::FADD, MVT::f32, Expand);
setLibcallName(RTLIB::FPEXT_F32_F64, "__hexagon_extendsfdf2");
setOperationAction(ISD::FP_EXTEND, MVT::f32, Expand);
setLibcallName(RTLIB::OEQ_F32, "__hexagon_eqsf2");
setCondCodeAction(ISD::SETOEQ, MVT::f32, Expand);
setLibcallName(RTLIB::OEQ_F64, "__hexagon_eqdf2");
setCondCodeAction(ISD::SETOEQ, MVT::f64, Expand);
setLibcallName(RTLIB::OGE_F32, "__hexagon_gesf2");
setCondCodeAction(ISD::SETOGE, MVT::f32, Expand);
setLibcallName(RTLIB::OGE_F64, "__hexagon_gedf2");
setCondCodeAction(ISD::SETOGE, MVT::f64, Expand);
setLibcallName(RTLIB::OGT_F32, "__hexagon_gtsf2");
setCondCodeAction(ISD::SETOGT, MVT::f32, Expand);
setLibcallName(RTLIB::OGT_F64, "__hexagon_gtdf2");
setCondCodeAction(ISD::SETOGT, MVT::f64, Expand);
setLibcallName(RTLIB::FPTOSINT_F64_I32, "__hexagon_fixdfsi");
setOperationAction(ISD::FP_TO_SINT, MVT::f64, Expand);
setLibcallName(RTLIB::FPTOSINT_F32_I32, "__hexagon_fixsfsi");
setOperationAction(ISD::FP_TO_SINT, MVT::f32, Expand);
setLibcallName(RTLIB::OLE_F64, "__hexagon_ledf2");
setCondCodeAction(ISD::SETOLE, MVT::f64, Expand);
setLibcallName(RTLIB::OLE_F32, "__hexagon_lesf2");
setCondCodeAction(ISD::SETOLE, MVT::f32, Expand);
setLibcallName(RTLIB::OLT_F64, "__hexagon_ltdf2");
setCondCodeAction(ISD::SETOLT, MVT::f64, Expand);
setLibcallName(RTLIB::OLT_F32, "__hexagon_ltsf2");
setCondCodeAction(ISD::SETOLT, MVT::f32, Expand);
setLibcallName(RTLIB::MUL_F64, "__hexagon_muldf3");
setOperationAction(ISD::FMUL, MVT::f64, Expand);
setLibcallName(RTLIB::MUL_F32, "__hexagon_mulsf3");
setOperationAction(ISD::MUL, MVT::f32, Expand);
setLibcallName(RTLIB::UNE_F64, "__hexagon_nedf2");
setCondCodeAction(ISD::SETUNE, MVT::f64, Expand);
setLibcallName(RTLIB::UNE_F32, "__hexagon_nesf2");
setLibcallName(RTLIB::SUB_F64, "__hexagon_subdf3");
setOperationAction(ISD::SUB, MVT::f64, Expand);
setLibcallName(RTLIB::SUB_F32, "__hexagon_subsf3");
setOperationAction(ISD::SUB, MVT::f32, Expand);
setLibcallName(RTLIB::FPROUND_F64_F32, "__hexagon_truncdfsf2");
setOperationAction(ISD::FP_ROUND, MVT::f64, Expand);
setLibcallName(RTLIB::UO_F64, "__hexagon_unorddf2");
setCondCodeAction(ISD::SETUO, MVT::f64, Expand);
setLibcallName(RTLIB::O_F64, "__hexagon_unorddf2");
setCondCodeAction(ISD::SETO, MVT::f64, Expand);
setLibcallName(RTLIB::O_F32, "__hexagon_unordsf2");
setCondCodeAction(ISD::SETO, MVT::f32, Expand);
setLibcallName(RTLIB::UO_F32, "__hexagon_unordsf2");
setCondCodeAction(ISD::SETUO, MVT::f32, Expand);
setOperationAction(ISD::FABS, MVT::f32, Expand);
setOperationAction(ISD::FABS, MVT::f64, Expand);
setOperationAction(ISD::FNEG, MVT::f32, Expand);
setOperationAction(ISD::FNEG, MVT::f64, Expand);
}
setLibcallName(RTLIB::SREM_I32, "__hexagon_modsi3");
setOperationAction(ISD::SREM, MVT::i32, Expand);
setIndexedLoadAction(ISD::POST_INC, MVT::i8, Legal);
setIndexedLoadAction(ISD::POST_INC, MVT::i16, Legal);
setIndexedLoadAction(ISD::POST_INC, MVT::i32, Legal);
setIndexedLoadAction(ISD::POST_INC, MVT::i64, Legal);
setIndexedStoreAction(ISD::POST_INC, MVT::i8, Legal);
setIndexedStoreAction(ISD::POST_INC, MVT::i16, Legal);
setIndexedStoreAction(ISD::POST_INC, MVT::i32, Legal);
setIndexedStoreAction(ISD::POST_INC, MVT::i64, Legal);
setOperationAction(ISD::BUILD_PAIR, MVT::i64, Expand);
// Turn FP extload into load/fextend.
setLoadExtAction(ISD::EXTLOAD, MVT::f32, Expand);
// Hexagon has a i1 sign extending load.
setLoadExtAction(ISD::SEXTLOAD, MVT::i1, Expand);
// Turn FP truncstore into trunc + store.
setTruncStoreAction(MVT::f64, MVT::f32, Expand);
// Custom legalize GlobalAddress nodes into CONST32.
setOperationAction(ISD::GlobalAddress, MVT::i32, Custom);
setOperationAction(ISD::GlobalAddress, MVT::i8, Custom);
setOperationAction(ISD::BlockAddress, MVT::i32, Custom);
// Truncate action?
setOperationAction(ISD::TRUNCATE, MVT::i64, Expand);
// Hexagon doesn't have sext_inreg, replace them with shl/sra.
setOperationAction(ISD::SIGN_EXTEND_INREG, MVT::i1 , Expand);
// Hexagon has no REM or DIVREM operations.
setOperationAction(ISD::UREM, MVT::i32, Expand);
setOperationAction(ISD::SREM, MVT::i32, Expand);
setOperationAction(ISD::SDIVREM, MVT::i32, Expand);
setOperationAction(ISD::UDIVREM, MVT::i32, Expand);
setOperationAction(ISD::SREM, MVT::i64, Expand);
setOperationAction(ISD::SDIVREM, MVT::i64, Expand);
setOperationAction(ISD::UDIVREM, MVT::i64, Expand);
setOperationAction(ISD::BSWAP, MVT::i64, Expand);
// Lower SELECT_CC to SETCC and SELECT.
setOperationAction(ISD::SELECT_CC, MVT::i32, Custom);
setOperationAction(ISD::SELECT_CC, MVT::i64, Custom);
if (QRI->Subtarget.hasV5TOps()) {
// We need to make the operation type of SELECT node to be Custom,
// such that we don't go into the infinite loop of
// select -> setcc -> select_cc -> select loop.
setOperationAction(ISD::SELECT, MVT::f32, Custom);
setOperationAction(ISD::SELECT, MVT::f64, Custom);
setOperationAction(ISD::SELECT_CC, MVT::f32, Expand);
setOperationAction(ISD::SELECT_CC, MVT::f64, Expand);
setOperationAction(ISD::SELECT_CC, MVT::Other, Expand);
} else {
// Hexagon has no select or setcc: expand to SELECT_CC.
setOperationAction(ISD::SELECT, MVT::f32, Expand);
setOperationAction(ISD::SELECT, MVT::f64, Expand);
// This is a workaround documented in DAGCombiner.cpp:2892 We don't
// support SELECT_CC on every type.
setOperationAction(ISD::SELECT_CC, MVT::Other, Expand);
}
if (EmitJumpTables) {
setOperationAction(ISD::BR_JT, MVT::Other, Custom);
} else {
setOperationAction(ISD::BR_JT, MVT::Other, Expand);
}
// Increase jump tables cutover to 5, was 4.
setMinimumJumpTableEntries(5);
setOperationAction(ISD::BR_CC, MVT::f32, Expand);
setOperationAction(ISD::BR_CC, MVT::f64, Expand);
setOperationAction(ISD::BR_CC, MVT::i1, Expand);
setOperationAction(ISD::BR_CC, MVT::i32, Expand);
setOperationAction(ISD::BR_CC, MVT::i64, Expand);
setOperationAction(ISD::ATOMIC_FENCE, MVT::Other, Custom);
setOperationAction(ISD::FSIN , MVT::f64, Expand);
setOperationAction(ISD::FCOS , MVT::f64, Expand);
setOperationAction(ISD::FREM , MVT::f64, Expand);
setOperationAction(ISD::FSIN , MVT::f32, Expand);
setOperationAction(ISD::FCOS , MVT::f32, Expand);
setOperationAction(ISD::FREM , MVT::f32, Expand);
setOperationAction(ISD::FSINCOS, MVT::f64, Expand);
setOperationAction(ISD::FSINCOS, MVT::f32, Expand);
// In V4, we have double word add/sub with carry. The problem with
// modelling this instruction is that it produces 2 results - Rdd and Px.
// To model update of Px, we will have to use Defs[p0..p3] which will
// cause any predicate live range to spill. So, we pretend we dont't
// have these instructions.
setOperationAction(ISD::ADDE, MVT::i8, Expand);
setOperationAction(ISD::ADDE, MVT::i16, Expand);
setOperationAction(ISD::ADDE, MVT::i32, Expand);
setOperationAction(ISD::ADDE, MVT::i64, Expand);
setOperationAction(ISD::SUBE, MVT::i8, Expand);
setOperationAction(ISD::SUBE, MVT::i16, Expand);
setOperationAction(ISD::SUBE, MVT::i32, Expand);
setOperationAction(ISD::SUBE, MVT::i64, Expand);
setOperationAction(ISD::ADDC, MVT::i8, Expand);
setOperationAction(ISD::ADDC, MVT::i16, Expand);
setOperationAction(ISD::ADDC, MVT::i32, Expand);
setOperationAction(ISD::ADDC, MVT::i64, Expand);
setOperationAction(ISD::SUBC, MVT::i8, Expand);
setOperationAction(ISD::SUBC, MVT::i16, Expand);
setOperationAction(ISD::SUBC, MVT::i32, Expand);
setOperationAction(ISD::SUBC, MVT::i64, Expand);
setOperationAction(ISD::CTPOP, MVT::i32, Expand);
setOperationAction(ISD::CTPOP, MVT::i64, Expand);
setOperationAction(ISD::CTTZ , MVT::i32, Expand);
setOperationAction(ISD::CTTZ , MVT::i64, Expand);
setOperationAction(ISD::CTTZ_ZERO_UNDEF, MVT::i32, Expand);
setOperationAction(ISD::CTTZ_ZERO_UNDEF, MVT::i64, Expand);
setOperationAction(ISD::CTLZ , MVT::i32, Expand);
setOperationAction(ISD::CTLZ , MVT::i64, Expand);
setOperationAction(ISD::CTLZ_ZERO_UNDEF, MVT::i32, Expand);
setOperationAction(ISD::CTLZ_ZERO_UNDEF, MVT::i64, Expand);
setOperationAction(ISD::ROTL , MVT::i32, Expand);
setOperationAction(ISD::ROTR , MVT::i32, Expand);
setOperationAction(ISD::BSWAP, MVT::i32, Expand);
setOperationAction(ISD::FCOPYSIGN, MVT::f64, Expand);
setOperationAction(ISD::FCOPYSIGN, MVT::f32, Expand);
setOperationAction(ISD::FPOW , MVT::f64, Expand);
setOperationAction(ISD::FPOW , MVT::f32, Expand);
setOperationAction(ISD::SHL_PARTS, MVT::i32, Expand);
setOperationAction(ISD::SRA_PARTS, MVT::i32, Expand);
setOperationAction(ISD::SRL_PARTS, MVT::i32, Expand);
setOperationAction(ISD::UMUL_LOHI, MVT::i32, Expand);
setOperationAction(ISD::SMUL_LOHI, MVT::i32, Expand);
setOperationAction(ISD::SMUL_LOHI, MVT::i64, Expand);
setOperationAction(ISD::UMUL_LOHI, MVT::i64, Expand);
setOperationAction(ISD::EH_RETURN, MVT::Other, Custom);
if (TM.getSubtargetImpl()->isSubtargetV2()) {
setExceptionPointerRegister(Hexagon::R20);
setExceptionSelectorRegister(Hexagon::R21);
} else {
setExceptionPointerRegister(Hexagon::R0);
setExceptionSelectorRegister(Hexagon::R1);
}
// VASTART needs to be custom lowered to use the VarArgsFrameIndex.
setOperationAction(ISD::VASTART , MVT::Other, Custom);
// Use the default implementation.
setOperationAction(ISD::VAARG , MVT::Other, Expand);
setOperationAction(ISD::VACOPY , MVT::Other, Expand);
setOperationAction(ISD::VAEND , MVT::Other, Expand);
setOperationAction(ISD::STACKSAVE , MVT::Other, Expand);
setOperationAction(ISD::STACKRESTORE , MVT::Other, Expand);
setOperationAction(ISD::DYNAMIC_STACKALLOC, MVT::i32 , Custom);
setOperationAction(ISD::INLINEASM , MVT::Other, Custom);
setMinFunctionAlignment(2);
// Needed for DYNAMIC_STACKALLOC expansion.
unsigned StackRegister = TM.getRegisterInfo()->getStackRegister();
setStackPointerRegisterToSaveRestore(StackRegister);
setSchedulingPreference(Sched::VLIW);
}
const char*
HexagonTargetLowering::getTargetNodeName(unsigned Opcode) const {
switch (Opcode) {
default: return 0;
case HexagonISD::CONST32: return "HexagonISD::CONST32";
case HexagonISD::CONST32_GP: return "HexagonISD::CONST32_GP";
case HexagonISD::CONST32_Int_Real: return "HexagonISD::CONST32_Int_Real";
case HexagonISD::ADJDYNALLOC: return "HexagonISD::ADJDYNALLOC";
case HexagonISD::CMPICC: return "HexagonISD::CMPICC";
case HexagonISD::CMPFCC: return "HexagonISD::CMPFCC";
case HexagonISD::BRICC: return "HexagonISD::BRICC";
case HexagonISD::BRFCC: return "HexagonISD::BRFCC";
case HexagonISD::SELECT_ICC: return "HexagonISD::SELECT_ICC";
case HexagonISD::SELECT_FCC: return "HexagonISD::SELECT_FCC";
case HexagonISD::Hi: return "HexagonISD::Hi";
case HexagonISD::Lo: return "HexagonISD::Lo";
case HexagonISD::FTOI: return "HexagonISD::FTOI";
case HexagonISD::ITOF: return "HexagonISD::ITOF";
case HexagonISD::CALL: return "HexagonISD::CALL";
case HexagonISD::RET_FLAG: return "HexagonISD::RET_FLAG";
case HexagonISD::BR_JT: return "HexagonISD::BR_JT";
case HexagonISD::TC_RETURN: return "HexagonISD::TC_RETURN";
case HexagonISD::EH_RETURN: return "HexagonISD::EH_RETURN";
}
}
bool
HexagonTargetLowering::isTruncateFree(Type *Ty1, Type *Ty2) const {
EVT MTy1 = EVT::getEVT(Ty1);
EVT MTy2 = EVT::getEVT(Ty2);
if (!MTy1.isSimple() || !MTy2.isSimple()) {
return false;
}
return ((MTy1.getSimpleVT() == MVT::i64) && (MTy2.getSimpleVT() == MVT::i32));
}
bool HexagonTargetLowering::isTruncateFree(EVT VT1, EVT VT2) const {
if (!VT1.isSimple() || !VT2.isSimple()) {
return false;
}
return ((VT1.getSimpleVT() == MVT::i64) && (VT2.getSimpleVT() == MVT::i32));
}
bool
HexagonTargetLowering::allowTruncateForTailCall(Type *Ty1, Type *Ty2) const {
// Assuming the caller does not have either a signext or zeroext modifier, and
// only one value is accepted, any reasonable truncation is allowed.
if (!Ty1->isIntegerTy() || !Ty2->isIntegerTy())
return false;
// FIXME: in principle up to 64-bit could be made safe, but it would be very
// fragile at the moment: any support for multiple value returns would be
// liable to disallow tail calls involving i64 -> iN truncation in many cases.
return Ty1->getPrimitiveSizeInBits() <= 32;
}
SDValue
HexagonTargetLowering::LowerEH_RETURN(SDValue Op, SelectionDAG &DAG) const {
SDValue Chain = Op.getOperand(0);
SDValue Offset = Op.getOperand(1);
SDValue Handler = Op.getOperand(2);
SDLoc dl(Op);
// Mark function as containing a call to EH_RETURN.
HexagonMachineFunctionInfo *FuncInfo =
DAG.getMachineFunction().getInfo<HexagonMachineFunctionInfo>();
FuncInfo->setHasEHReturn();
unsigned OffsetReg = Hexagon::R28;
SDValue StoreAddr = DAG.getNode(ISD::ADD, dl, getPointerTy(),
DAG.getRegister(Hexagon::R30, getPointerTy()),
DAG.getIntPtrConstant(4));
Chain = DAG.getStore(Chain, dl, Handler, StoreAddr, MachinePointerInfo(),
false, false, 0);
Chain = DAG.getCopyToReg(Chain, dl, OffsetReg, Offset);
// Not needed we already use it as explict input to EH_RETURN.
// MF.getRegInfo().addLiveOut(OffsetReg);
return DAG.getNode(HexagonISD::EH_RETURN, dl, MVT::Other, Chain);
}
SDValue
HexagonTargetLowering::LowerOperation(SDValue Op, SelectionDAG &DAG) const {
switch (Op.getOpcode()) {
default: llvm_unreachable("Should not custom lower this!");
case ISD::ConstantPool: return LowerConstantPool(Op, DAG);
case ISD::EH_RETURN: return LowerEH_RETURN(Op, DAG);
// Frame & Return address. Currently unimplemented.
case ISD::RETURNADDR: return LowerRETURNADDR(Op, DAG);
case ISD::FRAMEADDR: return LowerFRAMEADDR(Op, DAG);
case ISD::GlobalTLSAddress:
llvm_unreachable("TLS not implemented for Hexagon.");
case ISD::ATOMIC_FENCE: return LowerATOMIC_FENCE(Op, DAG);
case ISD::GlobalAddress: return LowerGLOBALADDRESS(Op, DAG);
case ISD::BlockAddress: return LowerBlockAddress(Op, DAG);
case ISD::VASTART: return LowerVASTART(Op, DAG);
case ISD::BR_JT: return LowerBR_JT(Op, DAG);
case ISD::DYNAMIC_STACKALLOC: return LowerDYNAMIC_STACKALLOC(Op, DAG);
case ISD::SELECT_CC: return LowerSELECT_CC(Op, DAG);
case ISD::SELECT: return Op;
case ISD::INTRINSIC_WO_CHAIN: return LowerINTRINSIC_WO_CHAIN(Op, DAG);
case ISD::INLINEASM: return LowerINLINEASM(Op, DAG);
}
}
//===----------------------------------------------------------------------===//
// Hexagon Scheduler Hooks
//===----------------------------------------------------------------------===//
MachineBasicBlock *
HexagonTargetLowering::EmitInstrWithCustomInserter(MachineInstr *MI,
MachineBasicBlock *BB)
const {
switch (MI->getOpcode()) {
case Hexagon::ADJDYNALLOC: {
MachineFunction *MF = BB->getParent();
HexagonMachineFunctionInfo *FuncInfo =
MF->getInfo<HexagonMachineFunctionInfo>();
FuncInfo->addAllocaAdjustInst(MI);
return BB;
}
default: llvm_unreachable("Unexpected instr type to insert");
} // switch
}
//===----------------------------------------------------------------------===//
// Inline Assembly Support
//===----------------------------------------------------------------------===//
std::pair<unsigned, const TargetRegisterClass*>
HexagonTargetLowering::getRegForInlineAsmConstraint(const
std::string &Constraint,
MVT VT) const {
if (Constraint.size() == 1) {
switch (Constraint[0]) {
case 'r': // R0-R31
switch (VT.SimpleTy) {
default:
llvm_unreachable("getRegForInlineAsmConstraint Unhandled data type");
case MVT::i32:
case MVT::i16:
case MVT::i8:
case MVT::f32:
return std::make_pair(0U, &Hexagon::IntRegsRegClass);
case MVT::i64:
case MVT::f64:
return std::make_pair(0U, &Hexagon::DoubleRegsRegClass);
}
default:
llvm_unreachable("Unknown asm register class");
}
}
return TargetLowering::getRegForInlineAsmConstraint(Constraint, VT);
}
/// isFPImmLegal - Returns true if the target can instruction select the
/// specified FP immediate natively. If false, the legalizer will
/// materialize the FP immediate as a load from a constant pool.
bool HexagonTargetLowering::isFPImmLegal(const APFloat &Imm, EVT VT) const {
const HexagonRegisterInfo* QRI = TM.getRegisterInfo();
return QRI->Subtarget.hasV5TOps();
}
/// isLegalAddressingMode - Return true if the addressing mode represented by
/// AM is legal for this target, for a load/store of the specified type.
bool HexagonTargetLowering::isLegalAddressingMode(const AddrMode &AM,
Type *Ty) const {
// Allows a signed-extended 11-bit immediate field.
if (AM.BaseOffs <= -(1LL << 13) || AM.BaseOffs >= (1LL << 13)-1) {
return false;
}
// No global is ever allowed as a base.
if (AM.BaseGV) {
return false;
}
int Scale = AM.Scale;
if (Scale < 0) Scale = -Scale;
switch (Scale) {
case 0: // No scale reg, "r+i", "r", or just "i".
break;
default: // No scaled addressing mode.
return false;
}
return true;
}
/// isLegalICmpImmediate - Return true if the specified immediate is legal
/// icmp immediate, that is the target has icmp instructions which can compare
/// a register against the immediate without having to materialize the
/// immediate into a register.
bool HexagonTargetLowering::isLegalICmpImmediate(int64_t Imm) const {
return Imm >= -512 && Imm <= 511;
}
/// IsEligibleForTailCallOptimization - Check whether the call is eligible
/// for tail call optimization. Targets which want to do tail call
/// optimization should implement this function.
bool HexagonTargetLowering::IsEligibleForTailCallOptimization(
SDValue Callee,
CallingConv::ID CalleeCC,
bool isVarArg,
bool isCalleeStructRet,
bool isCallerStructRet,
const SmallVectorImpl<ISD::OutputArg> &Outs,
const SmallVectorImpl<SDValue> &OutVals,
const SmallVectorImpl<ISD::InputArg> &Ins,
SelectionDAG& DAG) const {
const Function *CallerF = DAG.getMachineFunction().getFunction();
CallingConv::ID CallerCC = CallerF->getCallingConv();
bool CCMatch = CallerCC == CalleeCC;
// ***************************************************************************
// Look for obvious safe cases to perform tail call optimization that do not
// require ABI changes.
// ***************************************************************************
// If this is a tail call via a function pointer, then don't do it!
if (!(dyn_cast<GlobalAddressSDNode>(Callee))
&& !(dyn_cast<ExternalSymbolSDNode>(Callee))) {
return false;
}
// Do not optimize if the calling conventions do not match.
if (!CCMatch)
return false;
// Do not tail call optimize vararg calls.
if (isVarArg)
return false;
// Also avoid tail call optimization if either caller or callee uses struct
// return semantics.
if (isCalleeStructRet || isCallerStructRet)
return false;
// In addition to the cases above, we also disable Tail Call Optimization if
// the calling convention code that at least one outgoing argument needs to
// go on the stack. We cannot check that here because at this point that
// information is not available.
return true;
}