bool MIRParserImpl::initializeFrameInfo(
const Function &F, MachineFrameInfo &MFI,
const yaml::MachineFunction &YamlMF,
DenseMap<unsigned, int> &StackObjectSlots,
DenseMap<unsigned, int> &FixedStackObjectSlots) {
const yaml::MachineFrameInfo &YamlMFI = YamlMF.FrameInfo;
MFI.setFrameAddressIsTaken(YamlMFI.IsFrameAddressTaken);
MFI.setReturnAddressIsTaken(YamlMFI.IsReturnAddressTaken);
MFI.setHasStackMap(YamlMFI.HasStackMap);
MFI.setHasPatchPoint(YamlMFI.HasPatchPoint);
MFI.setStackSize(YamlMFI.StackSize);
MFI.setOffsetAdjustment(YamlMFI.OffsetAdjustment);
if (YamlMFI.MaxAlignment)
MFI.ensureMaxAlignment(YamlMFI.MaxAlignment);
MFI.setAdjustsStack(YamlMFI.AdjustsStack);
MFI.setHasCalls(YamlMFI.HasCalls);
MFI.setMaxCallFrameSize(YamlMFI.MaxCallFrameSize);
MFI.setHasOpaqueSPAdjustment(YamlMFI.HasOpaqueSPAdjustment);
MFI.setHasVAStart(YamlMFI.HasVAStart);
MFI.setHasMustTailInVarArgFunc(YamlMFI.HasMustTailInVarArgFunc);
// Initialize the fixed frame objects.
for (const auto &Object : YamlMF.FixedStackObjects) {
int ObjectIdx;
if (Object.Type != yaml::FixedMachineStackObject::SpillSlot)
ObjectIdx = MFI.CreateFixedObject(Object.Size, Object.Offset,
Object.IsImmutable, Object.IsAliased);
else
ObjectIdx = MFI.CreateFixedSpillStackObject(Object.Size, Object.Offset);
MFI.setObjectAlignment(ObjectIdx, Object.Alignment);
// TODO: Report an error when objects are redefined.
FixedStackObjectSlots.insert(std::make_pair(Object.ID, ObjectIdx));
}
// Initialize the ordinary frame objects.
for (const auto &Object : YamlMF.StackObjects) {
int ObjectIdx;
const AllocaInst *Alloca = nullptr;
const yaml::StringValue &Name = Object.Name;
if (!Name.Value.empty()) {
Alloca = dyn_cast_or_null<AllocaInst>(
F.getValueSymbolTable().lookup(Name.Value));
if (!Alloca)
return error(Name.SourceRange.Start,
"alloca instruction named '" + Name.Value +
"' isn't defined in the function '" + F.getName() +
"'");
}
if (Object.Type == yaml::MachineStackObject::VariableSized)
ObjectIdx = MFI.CreateVariableSizedObject(Object.Alignment, Alloca);
else
ObjectIdx = MFI.CreateStackObject(
Object.Size, Object.Alignment,
Object.Type == yaml::MachineStackObject::SpillSlot, Alloca);
MFI.setObjectOffset(ObjectIdx, Object.Offset);
// TODO: Report an error when objects are redefined.
StackObjectSlots.insert(std::make_pair(Object.ID, ObjectIdx));
}
return false;
}
/// calculateCallsInformation - Calculate the MaxCallFrameSize and HasCalls
/// variables for the function's frame information and eliminate call frame
/// pseudo instructions.
void PEI::calculateCallsInformation(MachineFunction &Fn) {
const TargetRegisterInfo *RegInfo = Fn.getTarget().getRegisterInfo();
unsigned MaxCallFrameSize = 0;
bool HasCalls = false;
// Get the function call frame set-up and tear-down instruction opcode
int FrameSetupOpcode = RegInfo->getCallFrameSetupOpcode();
int FrameDestroyOpcode = RegInfo->getCallFrameDestroyOpcode();
// Early exit for targets which have no call frame setup/destroy pseudo
// instructions.
if (FrameSetupOpcode == -1 && FrameDestroyOpcode == -1)
return;
std::vector<MachineBasicBlock::iterator> FrameSDOps;
for (MachineFunction::iterator BB = Fn.begin(), E = Fn.end(); BB != E; ++BB)
for (MachineBasicBlock::iterator I = BB->begin(); I != BB->end(); ++I)
if (I->getOpcode() == FrameSetupOpcode ||
I->getOpcode() == FrameDestroyOpcode) {
assert(I->getNumOperands() >= 1 && "Call Frame Setup/Destroy Pseudo"
" instructions should have a single immediate argument!");
unsigned Size = I->getOperand(0).getImm();
if (Size > MaxCallFrameSize) MaxCallFrameSize = Size;
HasCalls = true;
FrameSDOps.push_back(I);
} else if (I->getOpcode() == TargetInstrInfo::INLINEASM) {
// An InlineAsm might be a call; assume it is to get the stack frame
// aligned correctly for calls.
HasCalls = true;
}
MachineFrameInfo *FFI = Fn.getFrameInfo();
FFI->setHasCalls(HasCalls);
FFI->setMaxCallFrameSize(MaxCallFrameSize);
for (std::vector<MachineBasicBlock::iterator>::iterator
i = FrameSDOps.begin(), e = FrameSDOps.end(); i != e; ++i) {
MachineBasicBlock::iterator I = *i;
// If call frames are not being included as part of the stack frame, and
// there is no dynamic allocation (therefore referencing frame slots off
// sp), leave the pseudo ops alone. We'll eliminate them later.
if (RegInfo->hasReservedCallFrame(Fn) || RegInfo->hasFP(Fn))
RegInfo->eliminateCallFramePseudoInstr(Fn, *I->getParent(), I);
}
}
