bool CallLowering::lowerCall(
MachineIRBuilder &MIRBuilder, ImmutableCallSite CS, unsigned ResReg,
ArrayRef<unsigned> ArgRegs, std::function<unsigned()> GetCalleeReg) const {
auto &DL = CS.getParent()->getParent()->getParent()->getDataLayout();
// First step is to marshall all the function's parameters into the correct
// physregs and memory locations. Gather the sequence of argument types that
// we'll pass to the assigner function.
SmallVector<ArgInfo, 8> OrigArgs;
unsigned i = 0;
unsigned NumFixedArgs = CS.getFunctionType()->getNumParams();
for (auto &Arg : CS.args()) {
ArgInfo OrigArg{ArgRegs[i], Arg->getType(), ISD::ArgFlagsTy{},
i < NumFixedArgs};
setArgFlags(OrigArg, i + AttributeList::FirstArgIndex, DL, CS);
// We don't currently support swifterror or swiftself args.
if (OrigArg.Flags.isSwiftError() || OrigArg.Flags.isSwiftSelf())
return false;
OrigArgs.push_back(OrigArg);
++i;
}
MachineOperand Callee = MachineOperand::CreateImm(0);
if (const Function *F = CS.getCalledFunction())
Callee = MachineOperand::CreateGA(F, 0);
else
Callee = MachineOperand::CreateReg(GetCalleeReg(), false);
ArgInfo OrigRet{ResReg, CS.getType(), ISD::ArgFlagsTy{}};
if (!OrigRet.Ty->isVoidTy())
setArgFlags(OrigRet, AttributeList::ReturnIndex, DL, CS);
return lowerCall(MIRBuilder, CS.getCallingConv(), Callee, OrigRet, OrigArgs);
}
