[VirtRegMap] Fix for PR17825. Do not ignore noreturn definitions when setting
isPhysRegUsed if the unwind information is required.
Indeed, the runtime may need a correct stack to be able to unwind the call.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@194271 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/VirtRegMap.cpp b/lib/CodeGen/VirtRegMap.cpp
index 0a08608..e0aa405 100644
--- a/lib/CodeGen/VirtRegMap.cpp
+++ b/lib/CodeGen/VirtRegMap.cpp
@@ -285,7 +285,11 @@
if (!MO.isGlobal())
continue;
const Function *Func = dyn_cast<Function>(MO.getGlobal());
- if (!Func || !Func->hasFnAttribute(Attribute::NoReturn))
+ if (!Func || !Func->hasFnAttribute(Attribute::NoReturn) ||
+ // We need to keep correct unwind information
+ // even if the function will not return, since the
+ // runtime may need it.
+ !Func->hasFnAttribute(Attribute::NoUnwind))
continue;
NoReturnInsts.insert(MI);
break;