}
// For now, limit to conditions that provide information about unknown
- // expressions.
+ // expressions. RHS also cannot contain add recurrences.
auto *LHSUnknown = dyn_cast<SCEVUnknown>(LHS);
- if (!LHSUnknown)
+ if (!LHSUnknown || containsAddRecurrence(RHS))
return;
// Check whether LHS has already been rewritten. In that case we want to
// chain further rewrites onto the already rewritten value.
auto I = RewriteMap.find(LHSUnknown->getValue());
const SCEV *RewrittenLHS = I != RewriteMap.end() ? I->second : LHS;
-
+ const SCEV *RewrittenRHS = nullptr;
// TODO: use information from more predicates.
switch (Predicate) {
case CmpInst::ICMP_ULT:
- if (!containsAddRecurrence(RHS))
- RewriteMap[LHSUnknown->getValue()] = getUMinExpr(
- RewrittenLHS, getMinusSCEV(RHS, getOne(RHS->getType())));
+ RewrittenRHS =
+ getUMinExpr(RewrittenLHS, getMinusSCEV(RHS, getOne(RHS->getType())));
break;
case CmpInst::ICMP_ULE:
- if (!containsAddRecurrence(RHS))
- RewriteMap[LHSUnknown->getValue()] = getUMinExpr(RewrittenLHS, RHS);
+ RewrittenRHS = getUMinExpr(RewrittenLHS, RHS);
break;
case CmpInst::ICMP_UGT:
- if (!containsAddRecurrence(RHS))
- RewriteMap[LHSUnknown->getValue()] =
- getUMaxExpr(RewrittenLHS, getAddExpr(RHS, getOne(RHS->getType())));
+ RewrittenRHS =
+ getUMaxExpr(RewrittenLHS, getAddExpr(RHS, getOne(RHS->getType())));
break;
case CmpInst::ICMP_UGE:
- if (!containsAddRecurrence(RHS))
- RewriteMap[LHSUnknown->getValue()] = getUMaxExpr(RewrittenLHS, RHS);
+ RewrittenRHS = getUMaxExpr(RewrittenLHS, RHS);
break;
case CmpInst::ICMP_EQ:
if (isa<SCEVConstant>(RHS))
- RewriteMap[LHSUnknown->getValue()] = RHS;
+ RewrittenRHS = RHS;
break;
case CmpInst::ICMP_NE:
if (isa<SCEVConstant>(RHS) &&
cast<SCEVConstant>(RHS)->getValue()->isNullValue())
- RewriteMap[LHSUnknown->getValue()] =
- getUMaxExpr(RewrittenLHS, getOne(RHS->getType()));
+ RewrittenRHS = getUMaxExpr(RewrittenLHS, getOne(RHS->getType()));
break;
default:
break;
}
+
+ if (RewrittenRHS)
+ RewriteMap[LHSUnknown->getValue()] = RewrittenRHS;
};
// Starting at the loop predecessor, climb up the predecessor chain, as long
// as there are predecessors that can be found that have unique successors