maxjhandsome
/
llvm-project
forked from OSchip/llvm-project
1
0
Fork 0
Code Issues Pull Requests Packages Releases Wiki Activity

[SelectionDAGBuilder] Don't set MachinePointerInfo for gather when we find a uniform base 

I believe we were previously calculating a pointer info with the scalar base and an offset of 0. But that's not really where the gather is pointing. The offset is a function of the indices of the GEP we looked through.

Also set the size of the MachineMemOperand to UnknownSize

Differential Revision: https://reviews.llvm.org/D76157
This commit is contained in:
Craig Topper 2020-03-17 11:02:25 -07:00
parent 9e2715aaac
commit 98369178bc
1 changed files with 18 additions and 34 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

52
llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
View File

@ -4377,7 +4377,7 @@ void SelectionDAGBuilder::visitMaskedStore(const CallInst &I,
// are looking for. If first operand of the GEP is a splat vector - we
// extract the splat value and use it as a uniform base.
// In all other cases the function returns 'false'.
static bool getUniformBase(const Value *&Ptr, SDValue &Base, SDValue &Index,
static bool getUniformBase(const Value *Ptr, SDValue &Base, SDValue &Index,
ISD::MemIndexType &IndexType, SDValue &Scale,
SelectionDAGBuilder *SDB) {
SelectionDAG& DAG = SDB->DAG;
@ -4388,11 +4388,12 @@ static bool getUniformBase(const Value *&Ptr, SDValue &Base, SDValue &Index,
if (!GEP)
return false;
const Value *GEPPtr = GEP->getPointerOperand();
if (!GEPPtr->getType()->isVectorTy())
Ptr = GEPPtr;
else if (!(Ptr = getSplatValue(GEPPtr)))
return false;
const Value *BasePtr = GEP->getPointerOperand();
if (BasePtr->getType()->isVectorTy()) {
BasePtr = getSplatValue(BasePtr);
if (!BasePtr)
return false;
}
unsigned FinalIndex = GEP->getNumOperands() - 1;
Value *IndexVal = GEP->getOperand(FinalIndex);
@ -4412,7 +4413,7 @@ static bool getUniformBase(const Value *&Ptr, SDValue &Base, SDValue &Index,
// The operands of the GEP may be defined in another basic block.
// In this case we'll not find nodes for the operands.
if (!SDB->findValue(Ptr))
if (!SDB->findValue(BasePtr))
return false;
Constant *C = dyn_cast<Constant>(IndexVal);
if (!C && !SDB->findValue(IndexVal))
@ -4434,7 +4435,7 @@ static bool getUniformBase(const Value *&Ptr, SDValue &Base, SDValue &Index,
SDB->getCurSDLoc(), TLI.getPointerTy(DL));
Index = SDB->getValue(IndexVal);
}
Base = SDB->getValue(Ptr);
Base = SDB->getValue(BasePtr);
IndexType = ISD::SIGNED_SCALED;
if (STy || !Index.getValueType().isVector()) {
@ -4465,17 +4466,15 @@ void SelectionDAGBuilder::visitMaskedScatter(const CallInst &I) {
SDValue Index;
ISD::MemIndexType IndexType;
SDValue Scale;
const Value *BasePtr = Ptr;
bool UniformBase = getUniformBase(BasePtr, Base, Index, IndexType, Scale,
this);
bool UniformBase = getUniformBase(Ptr, Base, Index, IndexType, Scale, this);
const Value *MemOpBasePtr = UniformBase ? BasePtr : nullptr;
unsigned AS = Ptr->getType()->getScalarType()->getPointerAddressSpace();
MachineMemOperand *MMO = DAG.getMachineFunction().
getMachineMemOperand(MachinePointerInfo(MemOpBasePtr),
getMachineMemOperand(MachinePointerInfo(AS),
MachineMemOperand::MOStore,
// TODO: Make MachineMemOperands aware of scalable
// vectors.
VT.getStoreSize().getKnownMinSize(),
MemoryLocation::UnknownSize,
Alignment, AAInfo);
if (!UniformBase) {
Base = DAG.getConstant(0, sdl, TLI.getPointerTy(DAG.getDataLayout()));
@ -4582,28 +4581,15 @@ void SelectionDAGBuilder::visitMaskedGather(const CallInst &I) {
SDValue Index;
ISD::MemIndexType IndexType;
SDValue Scale;
const Value *BasePtr = Ptr;
bool UniformBase = getUniformBase(BasePtr, Base, Index, IndexType, Scale,
this);
bool ConstantMemory = false;
if (UniformBase && AA &&
AA->pointsToConstantMemory(
MemoryLocation(BasePtr,
LocationSize::precise(
DAG.getDataLayout().getTypeStoreSize(I.getType())),
AAInfo))) {
// Do not serialize (non-volatile) loads of constant memory with anything.
Root = DAG.getEntryNode();
ConstantMemory = true;
}
bool UniformBase = getUniformBase(Ptr, Base, Index, IndexType, Scale, this);
unsigned AS = Ptr->getType()->getScalarType()->getPointerAddressSpace();
MachineMemOperand *MMO =
DAG.getMachineFunction().
getMachineMemOperand(MachinePointerInfo(UniformBase ? BasePtr : nullptr),
getMachineMemOperand(MachinePointerInfo(AS),
MachineMemOperand::MOLoad,
// TODO: Make MachineMemOperands aware of scalable
// vectors.
VT.getStoreSize().getKnownMinSize(),
MemoryLocation::UnknownSize,
Alignment, AAInfo, Ranges);
if (!UniformBase) {
@ -4616,9 +4602,7 @@ void SelectionDAGBuilder::visitMaskedGather(const CallInst &I) {
SDValue Gather = DAG.getMaskedGather(DAG.getVTList(VT, MVT::Other), VT, sdl,
Ops, MMO, IndexType);
SDValue OutChain = Gather.getValue(1);
if (!ConstantMemory)
PendingLoads.push_back(OutChain);
PendingLoads.push_back(Gather.getValue(1));
setValue(&I, Gather);
}