make sure to set Changed=true when instcombine hacks on the code,
not doing so prevents it from properly iterating and prevents it
from deleting the entire body of dce-iterate.ll
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@63476 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Transforms/Scalar/InstructionCombining.cpp b/lib/Transforms/Scalar/InstructionCombining.cpp
index 7f75928..6c57151 100644
--- a/lib/Transforms/Scalar/InstructionCombining.cpp
+++ b/lib/Transforms/Scalar/InstructionCombining.cpp
@@ -12356,6 +12356,7 @@
if (!I->use_empty())
I->replaceAllUsesWith(UndefValue::get(I->getType()));
I->eraseFromParent();
+ Changed = true;
}
}
}
@@ -12375,6 +12376,7 @@
I->eraseFromParent();
RemoveFromWorkList(I);
+ Changed = true;
continue;
}
@@ -12389,17 +12391,19 @@
++NumConstProp;
I->eraseFromParent();
RemoveFromWorkList(I);
+ Changed = true;
continue;
}
if (TD && I->getType()->getTypeID() == Type::VoidTyID) {
// See if we can constant fold its operands.
- for (User::op_iterator i = I->op_begin(), e = I->op_end(); i != e; ++i) {
- if (ConstantExpr *CE = dyn_cast<ConstantExpr>(i)) {
+ for (User::op_iterator i = I->op_begin(), e = I->op_end(); i != e; ++i)
+ if (ConstantExpr *CE = dyn_cast<ConstantExpr>(i))
if (Constant *NewC = ConstantFoldConstantExpression(CE, TD))
- i->set(NewC);
- }
- }
+ if (NewC != CE) {
+ i->set(NewC);
+ Changed = true;
+ }
}
// See if we can trivially sink this instruction to a successor basic block.