/// BuildLookup - Build instructions with Builder to retrieve the value at
/// the position given by Index in the lookup table.
- Value *BuildLookup(Value *Index, IRBuilder<> &Builder);
+ Value *BuildLookup(Value *Index, uint64_t TableSize, IRBuilder<> &Builder);
/// WouldFitInRegister - Return true if a table with TableSize elements of
/// type ElementType would fit in a target-legal register.
Kind = ArrayKind;
}
-Value *SwitchLookupTable::BuildLookup(Value *Index, IRBuilder<> &Builder) {
+Value *SwitchLookupTable::BuildLookup(Value *Index, uint64_t TableSize,
+ IRBuilder<> &Builder) {
switch (Kind) {
case SingleValueKind:
return SingleValue;
"switch.masked");
}
case ArrayKind: {
+ // Make sure the table index will not overflow when treated as signed.
+ if (IntegerType *IT = dyn_cast<IntegerType>(Index->getType()))
+ if (TableSize > (1 << (IT->getBitWidth() - 1)))
+ Index = Builder.CreateZExt(Index,
+ IntegerType::get(IT->getContext(),
+ IT->getBitWidth() + 1),
+ "switch.tableidx.zext");
+
Value *GEPIndices[] = { Builder.getInt32(0), Index };
Value *GEP = Builder.CreateInBoundsGEP(Array, GEPIndices,
"switch.gep");
SI->getDefaultDest()->removePredecessor(SI->getParent());
} else {
Value *Cmp = Builder.CreateICmpULT(TableIndex, ConstantInt::get(
- MinCaseVal->getType(), TableSize));
+ MinCaseVal->getType(), TableSize));
Builder.CreateCondBr(Cmp, LookupBB, SI->getDefaultDest());
}
SwitchLookupTable Table(Mod, TableSize, MinCaseVal, ResultLists[PHI],
DV, DL);
- Value *Result = Table.BuildLookup(TableIndex, Builder);
+ Value *Result = Table.BuildLookup(TableIndex, TableSize, Builder);
// If the result is used to return immediately from the function, we want to
// do that right here.