setValue(&I, StoreNode);
}
-// Gather/scatter receive a vector of pointers.
-// This vector of pointers may be represented as a base pointer + vector of
-// indices, it depends on GEP and instruction preceding GEP
-// that calculates indices
+// Get a uniform base for the Gather/Scatter intrinsic.
+// The first argument of the Gather/Scatter intrinsic is a vector of pointers.
+// We try to represent it as a base pointer + vector of indices.
+// Usually, the vector of pointers comes from a 'getelementptr' instruction.
+// The first operand of the GEP may be a single pointer or a vector of pointers
+// Example:
+// %gep.ptr = getelementptr i32, <8 x i32*> %vptr, <8 x i32> %ind
+// or
+// %gep.ptr = getelementptr i32, i32* %ptr, <8 x i32> %ind
+// %res = call <8 x i32> @llvm.masked.gather.v8i32(<8 x i32*> %gep.ptr, ..
+//
+// When the first GEP operand is a single pointer - it is the uniform base we
+// are looking for. If first operand of the GEP is a splat vector - we
+// extract the spalt value and use it as a uniform base.
+// In all other cases the function returns 'false'.
+//
static bool getUniformBase(Value *& Ptr, SDValue& Base, SDValue& Index,
SelectionDAGBuilder* SDB) {
- assert(Ptr->getType()->isVectorTy() && "Unexpected pointer type");
+ SelectionDAG& DAG = SDB->DAG;
+ LLVMContext &Context = *DAG.getContext();
+
+ assert(Ptr->getType()->isVectorTy() && "Uexpected pointer type");
GetElementPtrInst *GEP = dyn_cast<GetElementPtrInst>(Ptr);
if (!GEP || GEP->getNumOperands() > 2)
return false;
- Value *GEPPtrs = GEP->getPointerOperand();
- if (!(Ptr = getSplatValue(GEPPtrs)))
- return false;
- SelectionDAG& DAG = SDB->DAG;
- const TargetLowering &TLI = DAG.getTargetLoweringInfo();
- // Check is the Ptr is inside current basic block
- // If not, look for the shuffle instruction
- if (SDB->findValue(Ptr))
- Base = SDB->getValue(Ptr);
- else if (SDB->findValue(GEPPtrs)) {
- SDValue GEPPtrsVal = SDB->getValue(GEPPtrs);
- SDLoc sdl = GEPPtrsVal;
- EVT IdxVT = TLI.getVectorIdxTy(DAG.getDataLayout());
- Base = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, sdl,
- GEPPtrsVal.getValueType().getScalarType(), GEPPtrsVal,
- DAG.getConstant(0, sdl, IdxVT));
- SDB->setValue(Ptr, Base);
- }
- else
+ Value *GEPPtr = GEP->getPointerOperand();
+ if (!GEPPtr->getType()->isVectorTy())
+ Ptr = GEPPtr;
+ else if (!(Ptr = getSplatValue(GEPPtr)))
return false;
Value *IndexVal = GEP->getOperand(1);
- if (SDB->findValue(IndexVal)) {
- Index = SDB->getValue(IndexVal);
- if (SExtInst* Sext = dyn_cast<SExtInst>(IndexVal)) {
+ // 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) || !SDB->findValue(IndexVal))
+ return false;
+
+ Base = SDB->getValue(Ptr);
+ Index = SDB->getValue(IndexVal);
+
+ // Suppress sign extension.
+ if (SExtInst* Sext = dyn_cast<SExtInst>(IndexVal)) {
+ if (SDB->findValue(Sext->getOperand(0))) {
IndexVal = Sext->getOperand(0);
- if (SDB->findValue(IndexVal))
- Index = SDB->getValue(IndexVal);
+ Index = SDB->getValue(IndexVal);
}
- return true;
}
- return false;
+ if (!Index.getValueType().isVector()) {
+ unsigned GEPWidth = GEP->getType()->getVectorNumElements();
+ EVT VT = EVT::getVectorVT(Context, Index.getValueType(), GEPWidth);
+ SmallVector<SDValue, 16> Ops(GEPWidth, Index);
+ Index = DAG.getNode(ISD::BUILD_VECTOR, SDLoc(Index), VT, Ops);
+ }
+ return true;
}
void SelectionDAGBuilder::visitMaskedScatter(const CallInst &I) {