[coroutines] Remove pass-through operator co_await; Replace it with the input expression
Reviewers: GorNishanov, rsmith
Reviewed By: GorNishanov
Differential Revision: https://reviews.llvm.org/D34216
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@305498 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/CGCoroutine.cpp b/lib/CodeGen/CGCoroutine.cpp
index daefb0e..a65faa6 100644
--- a/lib/CodeGen/CGCoroutine.cpp
+++ b/lib/CodeGen/CGCoroutine.cpp
@@ -160,19 +160,6 @@
bool ignoreResult, bool forLValue) {
auto *E = S.getCommonExpr();
- // FIXME: rsmith 5/22/2017. Does it still make sense for us to have a
- // UO_Coawait at all? As I recall, the only purpose it ever had was to
- // represent a dependent co_await expression that couldn't yet be resolved to
- // a CoawaitExpr. But now we have (and need!) a separate DependentCoawaitExpr
- // node to store unqualified lookup results, it seems that the UnaryOperator
- // portion of the representation serves no purpose (and as seen in this patch,
- // it's getting in the way). Can we remove it?
-
- // Skip passthrough operator co_await (present when awaiting on an LValue).
- if (auto *UO = dyn_cast<UnaryOperator>(E))
- if (UO->getOpcode() == UO_Coawait)
- E = UO->getSubExpr();
-
auto Binder =
CodeGenFunction::OpaqueValueMappingData::bind(CGF, S.getOpaqueValue(), E);
auto UnbindOnExit = llvm::make_scope_exit([&] { Binder.unbind(CGF); });
diff --git a/lib/Sema/SemaExpr.cpp b/lib/Sema/SemaExpr.cpp
index 0f8f5c2..75a6903 100644
--- a/lib/Sema/SemaExpr.cpp
+++ b/lib/Sema/SemaExpr.cpp
@@ -12057,11 +12057,17 @@
}
break;
case UO_Extension:
- case UO_Coawait:
resultType = Input.get()->getType();
VK = Input.get()->getValueKind();
OK = Input.get()->getObjectKind();
break;
+ case UO_Coawait:
+ // It's unnessesary to represent the pass-through operator co_await in the
+ // AST; just return the input expression instead.
+ assert(!Input.get()->getType()->isDependentType() &&
+ "the co_await expression must be non-dependant before "
+ "building operator co_await");
+ return Input;
}
if (resultType.isNull() || Input.isInvalid())
return ExprError();
