Value *BlockGenerator::getNewValue(const Value *Old, ValueMapT &BBMap,
ValueMapT &GlobalMap, LoopToScevMapT <S,
Loop *L) {
if (Value *New = lookupAvailableValue(Old, BBMap, GlobalMap))
return New;
if (SCEVCodegen && SE.isSCEVable(Old->getType()))
if (const SCEV *Scev = SE.getSCEVAtScope(const_cast<Value *>(Old), L)) {
if (!isa<SCEVCouldNotCompute>(Scev)) {
const SCEV *NewScev = apply(Scev, LTS, SE);
ValueToValueMap VTV;
VTV.insert(BBMap.begin(), BBMap.end());
VTV.insert(GlobalMap.begin(), GlobalMap.end());
NewScev = SCEVParameterRewriter::rewrite(NewScev, SE, VTV);
SCEVExpander Expander(SE, "polly");
Value *Expanded = Expander.expandCodeFor(NewScev, Old->getType(),
Builder.GetInsertPoint());
BBMap[Old] = Expanded;
return Expanded;
}
}
// Now the scalar dependence is neither available nor SCEVCodegenable, this
// should never happen in the current code generator.
llvm_unreachable("Unexpected scalar dependence in region!");
return nullptr;
}
Value *BlockGenerator::getNewValue(ScopStmt &Stmt, const Value *Old,
ValueMapT &BBMap, ValueMapT &GlobalMap,
LoopToScevMapT <S, Loop *L) const {
// We assume constants never change.
// This avoids map lookups for many calls to this function.
if (isa<Constant>(Old))
return const_cast<Value *>(Old);
if (Value *New = GlobalMap.lookup(Old)) {
if (Old->getType()->getScalarSizeInBits() <
New->getType()->getScalarSizeInBits())
New = Builder.CreateTruncOrBitCast(New, Old->getType());
return New;
}
if (Value *New = BBMap.lookup(Old))
return New;
if (SE.isSCEVable(Old->getType()))
if (const SCEV *Scev = SE.getSCEVAtScope(const_cast<Value *>(Old), L)) {
if (!isa<SCEVCouldNotCompute>(Scev)) {
const SCEV *NewScev = apply(Scev, LTS, SE);
ValueToValueMap VTV;
VTV.insert(BBMap.begin(), BBMap.end());
VTV.insert(GlobalMap.begin(), GlobalMap.end());
NewScev = SCEVParameterRewriter::rewrite(NewScev, SE, VTV);
SCEVExpander Expander(SE, Stmt.getParent()
->getRegion()
.getEntry()
->getParent()
->getParent()
->getDataLayout(),
"polly");
Value *Expanded = Expander.expandCodeFor(NewScev, Old->getType(),
Builder.GetInsertPoint());
BBMap[Old] = Expanded;
return Expanded;
}
}
// A scop-constant value defined by a global or a function parameter.
if (isa<GlobalValue>(Old) || isa<Argument>(Old))
return const_cast<Value *>(Old);
// A scop-constant value defined by an instruction executed outside the scop.
if (const Instruction *Inst = dyn_cast<Instruction>(Old))
if (!Stmt.getParent()->getRegion().contains(Inst->getParent()))
return const_cast<Value *>(Old);
// The scalar dependence is neither available nor SCEVCodegenable.
llvm_unreachable("Unexpected scalar dependence in region!");
return nullptr;
}
