Fix the conditions under which SCCP should examine insertvalue
instructions. Thanks to Matthijs Kooijman for pointing this out!
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52542 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Transforms/Scalar/SCCP.cpp b/lib/Transforms/Scalar/SCCP.cpp
index dc6d497..3ca03b3 100644
--- a/lib/Transforms/Scalar/SCCP.cpp
+++ b/lib/Transforms/Scalar/SCCP.cpp
@@ -750,7 +750,7 @@
Value *Val = IVI.getOperand(1);
// If the operand to the getresult is an undef, the result is undef.
- if (isa<UndefValue>(Aggr))
+ if (isa<UndefValue>(Aggr) && isa<UndefValue>(Val))
return;
// Currently only handle single-index insertvalues.
@@ -758,6 +758,23 @@
markOverdefined(&IVI);
return;
}
+
+ // Currently only handle insertvalue instructions that are in a single-use
+ // chain that builds up a return value.
+ for (const InsertValueInst *TmpIVI = &IVI; ; ) {
+ if (!TmpIVI->hasOneUse()) {
+ markOverdefined(&IVI);
+ return;
+ }
+ const Value *V = *TmpIVI->use_begin();
+ if (isa<ReturnInst>(V))
+ break;
+ TmpIVI = dyn_cast<InsertValueInst>(V);
+ if (!TmpIVI) {
+ markOverdefined(&IVI);
+ return;
+ }
+ }
// See if we are tracking the result of the callee.
Function *F = IVI.getParent()->getParent();