[CodeGen] Ignore OpaqueValueExprs that are unique references to their

source expressions when iterating over a PseudoObjectExpr's semantic
subexpression list.

Previously the loop in emitPseudoObjectExpr would emit the IR for each
OpaqueValueExpr that was in a PseudoObjectExpr's semantic-form
expression list and use the result when the OpaqueValueExpr later
appeared in other expressions. This caused an assertion failure when
AggExprEmitter tried to copy the result of an OpaqueValueExpr and the
copied type didn't have trivial copy/move constructors or assignment
operators.

This patch adds flag IsUnique to OpaqueValueExpr which indicates it is a
unique reference to its source expression (it is not used in multiple
places). The loop in emitPseudoObjectExpr ignores OpaqueValueExprs that
are unique and CodeGen visitors simply traverse the source expressions
of such OpaqueValueExprs.

rdar://problem/34363596

Differential Revision: https://reviews.llvm.org/D39562

llvm-svn: 327939

1 files changed, 6 insertions, 20 deletions

diff --git a/clang/lib/CodeGen/CodeGenFunction.h b/clang/lib/CodeGen/CodeGenFunction.h
index 5852788e296..709e7f4ad8d 100644
--- a/clang/lib/CodeGen/CodeGenFunction.h
+++ b/clang/lib/CodeGen/CodeGenFunction.h
@@ -2148,27 +2148,13 @@ public:
     return it->second;
   }
 
-  /// getOpaqueLValueMapping - Given an opaque value expression (which
-  /// must be mapped to an l-value), return its mapping.
-  const LValue &getOpaqueLValueMapping(const OpaqueValueExpr *e) {
-    assert(OpaqueValueMapping::shouldBindAsLValue(e));
-
-    llvm::DenseMap<const OpaqueValueExpr*,LValue>::iterator
-      it = OpaqueLValues.find(e);
-    assert(it != OpaqueLValues.end() && "no mapping for opaque value!");
-    return it->second;
-  }
-
-  /// getOpaqueRValueMapping - Given an opaque value expression (which
-  /// must be mapped to an r-value), return its mapping.
-  const RValue &getOpaqueRValueMapping(const OpaqueValueExpr *e) {
-    assert(!OpaqueValueMapping::shouldBindAsLValue(e));
+  /// Given an opaque value expression, return its LValue mapping if it exists,
+  /// otherwise create one.
+  LValue getOrCreateOpaqueLValueMapping(const OpaqueValueExpr *e);
 
-    llvm::DenseMap<const OpaqueValueExpr*,RValue>::iterator
-      it = OpaqueRValues.find(e);
-    assert(it != OpaqueRValues.end() && "no mapping for opaque value!");
-    return it->second;
-  }
+  /// Given an opaque value expression, return its RValue mapping if it exists,
+  /// otherwise create one.
+  RValue getOrCreateOpaqueRValueMapping(const OpaqueValueExpr *e);
 
   /// Get the index of the current ArrayInitLoopExpr, if any.
   llvm::Value *getArrayInitIndex() { return ArrayInitIndex; }