avoid type mismatch when building SCEVs
This is a corner case I have stumbled upon when dealing with ARM64 type
conversions. I was not able to extract a testcase for the community codebase to
fail on. The patch conservatively discards a division that would have ended up
in an ICE due to a type mismatch when building a multiply expression. I have
also added code to a place that builds add expressions and in which we should be
careful not to pass in operands of different types.
llvm-svn: 209694
diff --git a/llvm/lib/Analysis/ScalarEvolution.cpp b/llvm/lib/Analysis/ScalarEvolution.cpp
index 4d85948..42a7aa2 100644
--- a/llvm/lib/Analysis/ScalarEvolution.cpp
+++ b/llvm/lib/Analysis/ScalarEvolution.cpp
@@ -7131,9 +7131,19 @@
void visitAddExpr(const SCEVAddExpr *Numerator) {
SmallVector<const SCEV *, 2> Qs, Rs;
+ Type *Ty = Denominator->getType();
+
for (const SCEV *Op : Numerator->operands()) {
const SCEV *Q, *R;
divide(SE, Op, Denominator, &Q, &R);
+
+ // Bail out if types do not match.
+ if (Ty != Q->getType() || Ty != R->getType()) {
+ Quotient = Zero;
+ Remainder = Numerator;
+ return;
+ }
+
Qs.push_back(Q);
Rs.push_back(R);
}
@@ -7150,9 +7160,17 @@
void visitMulExpr(const SCEVMulExpr *Numerator) {
SmallVector<const SCEV *, 2> Qs;
+ Type *Ty = Denominator->getType();
bool FoundDenominatorTerm = false;
for (const SCEV *Op : Numerator->operands()) {
+ // Bail out if types do not match.
+ if (Ty != Op->getType()) {
+ Quotient = Zero;
+ Remainder = Numerator;
+ return;
+ }
+
if (FoundDenominatorTerm) {
Qs.push_back(Op);
continue;
@@ -7165,6 +7183,14 @@
Qs.push_back(Op);
continue;
}
+
+ // Bail out if types do not match.
+ if (Ty != Q->getType()) {
+ Quotient = Zero;
+ Remainder = Numerator;
+ return;
+ }
+
FoundDenominatorTerm = true;
Qs.push_back(Q);
}